v d.‘ u #73 .. ‘ . $523)"? .1 :34. fit; 31‘ up. 'J 13. L .135 T. av" rpm” « 3‘11“." .33" w, m w v. .. ,_ an. . ,3- , . '«W‘ ' r "'4 ‘3m '2". H u .53.". " 1'2"" ‘ , 4,2}? ,. .. 1v: “ v' ,. ;'.';3{.:.j~;r .. .3: fit. an ~ "' L‘ my! a .,. u. ”a ~e~ 1111111111111111111111111111111 11111111111111 l 3 12930 This is to certify that the thesis entitled IDENTIFICATION OF RAPD MARKERS ASSOCIATED WITH CANNING QUALITY IN NAVY BEANS presented by Kimberly J. Walters has been accepted towards fulfillment of the requirements for Master of Science degree in P1ant Breeding and Genetics Major professor / Date BI/ZO/gg 0-7639 MS U i: an Affirmative Action/Equal Opportunity Institution LIBRARY Mk’higan State University I a PLACE ll RETURN BOX to man this checkout iron your rocord. TO AVOID FINES Mum on or baton duo duo. DATE DUE DATE DUE DATE DUE MSU to An Afflnnutm MioNEmol Opportunity Institution Walla-9.1 IDENTIFICATION OF RAPD MARKERS ASSOCIATED WITH CANNING . QUALITY IN NAVY BEANS By Kimberly J. Walters A THESIS Submitted to Michigan State University in partial fulfillment of the requirements for the degree of MASTER OF SCIENCE Plant Breeding and Genetics Program Department of Crop and Soil Science 1995 ABSTRACT IDENTIFICATION OF RAPD MARKERS ASSOCIATED WITH CANNING QUALITY IN NAVY BEANS By Kimberly J. Walters RAPD markers associated with QTLs for canning quality in three populations of navy beans were identified. Each population consisted of recombinant inbred lines (RILs) derived from crosses between a superior canning and an inferior canning parent. Materials were grown and evaluated at two locations for two years. Traits measured included: visual appeal, texture, washed drained weight, hydration coeficient and percent solids lost. Marker-QTL associations were established using the General Linear Model procedure with significance set at P<0.05. The putative linkage groups were assigned using MAPMAKER (LOD = 3.00). Location and/or population specificity was common among the markers identified. R2 values for individual markers ranged fi'om 0.10 - 0.38 and R2 values for groups of markers used in multiple regression analyses ranged from 0.15 - 0.74. Heritability estimates were calculated on an entry mean basis for visual score, texture and washed drained weight and were moderate to high in value ( 0.48 - 0.96). Negative correlations were found between visual appeal score (VIS) and washed drained weight (WDWT), percent solids lost (SL) and WDWT as well as hydration coefficient (HC) and WDWT. In contrast, VIS and texture (TXT) were positively correlated. Marker data reflected these correlations. ACKNOWLEDGMENTS I would like to express my gratitude to my committee members, Dr. George L. Hosfield, Dr. James D. Kelly and Dr. Mark A. Uebersax for their invaluable assistance in the design and execution of my research project and for their insight during the preparation of this thesis. A special thanks goes to Dr. Kelly for helping me to learn the art and science of plant breeding. I would also like to thank Jerry Taylor, Norm Blakely, Theresa Wood, Bernie Marchetti and Jenny Clark for their help in the field and in the processing lab and all those who helped with the visual evaluations. Finally, to mom, dad, Shany, Nate and Chrissy, without your love, support, encouragement, and prayers I wouldn’t be where I am today-«thank you! iii TABLE OF CONTENTS LIST OF TABLES ................................................................................................ v LIST OF FIGURES ............................................................................................... viii INTRODUCTION ................................................................................................. 1 LITERATURE REVIEW ...................................................................................... 3 Processing Quality ...................................................................................... 3 Genetics of Canning Quality ....................................................................... 7 Markers for Mapping/Studying QTLs ......................................................... 9 MATERIALS AND METHODS ........................................................................... 18 RESULTS ............................................................................................................. 28 DISCUSSION ....................................................................................................... 46 SUMMARY .......................................................................................................... 53 APPENDIX ........................................................................................................... 55 LIST OF REFERENCES ....................................................................................... 70 iv Table 1. Table 2. Table 3. Table 4. Table 5a. Table 5b. Table 6a. Table 6b. Table 7a. LIST OF TABLES Minimum numbers of randomly placed molecular marker loci for the likely detection of substantial associations with important QTLs at difi‘erent times after crossing two inbred lines in typical diploid, tetraploid and hexaploid crop plants (adapted fi'om Lande, 1992). Significant sources of. variation for visual appeal (VIS), texture (TXT), hydration coeflicient (HC), washed drained weight ‘ (WDWT) and percent solids lost (SL) in population 2 (PZ), population 4 (P4) and population 5 (PS) ......................................... Markers significantly associated with canning quality traits in two of the three navy bean populations. ................................................. Proportion of phenotypic variation accounted for by selected markers using multiple regression ................................................... Efl‘ectiveness of selected markers for visual appeal (VIS), texture (TXT), hydration coeficient (HC), washed drained weight (WDWT) and percent solids lost (SL) for identifying recombinant inbred lines with high visual scores in population two ...................... Efl‘ectiveness of a composite of markers for visual appeal (VIS) fi'om three populations for identifying recombinant inbred lines with high visual scores in population two ................................................ Effectiveness of selected markers for visual appeal (VIS), texture (TXT), hydration coefficient (HC), washed drained weight (WDWT) and percent solids lost (SL) for identifying recombinant inbred lines with high visual scores in population four. .................... Effectiveness of a composite of markers for visual appeal (VIS) from three populations for identifying recombinant inbred lines with high visual scores in population four. .............................................. Efi‘ectiveness of selected markers for visual appeal (VIS), texture (TXT), hydration coefficient (HC), washed drained weight (WDWT) and percent solids lost (SL) for identifying recombinant inbred lines with high visual scores in population five. ..................... 16 34 36 37 39 39 41 41 42 Table 7b. Table 8. Table 9. Table 10. Table A 1. Table A2. Table A3. Table A4. Table A5. Table A6. Table A7. Table A8. Table A9. Table A10. Table All. Table A 12. Table A13. Table A14. Efi'ectiveness of a composite of markers for visual appeal (VIS) from three populations for identifying recombinant inbred lines with high visual scores in population five. ............................................... 42 Efl‘ectiveness of selection based on a composite of markers for visual appeal (VIS) and texture (TXT) from three populations ........ 42 Heritability estimates for visual appeal (VIS), washed drained weight (WDWT) and percent solids lost (SL). .............................. 44 Correlation coeflicients between canning quality traits in three populations of navy beans. .............................................................. 44 Form of the analysis of variance for VIS in population 2. ................ 55 Form of the analysis of variance for TXT in population 2 ................ 55 Form of the analysis of variance for WDWT in population 2 ........... 55 Form of the analysis of variance for VIS in population 4 ................. 56 Form of the analysis of variance for TXT in population 4 ................ 56 Form of the analysis of variance for WDWT in population 4 ........... 56 Form of the analysis of variance for VIS in population 5 ................. 57 Form of the analysis of variance for TXT in population 5 ................ 57 Form of the analysis of variance for WDWT in population 5 ........... 57 Markers significantly associated (P<0.05) with visual score in three populations of navy beans. .............................................................. 58 Markers significantly associated (P<0.05) with texture in three populations of navy beans. .............................................................. 59 Markers significantly associated (P<0.0S) with washed drained weight in three populations of navy beans ....................................... 60 Markers significantly associated (P<0.05) with hydration coeficient in three populations of navy beans ................................................... 61 Markers significantly associated (P<0.05) with percent solids lost in three populations of navy beans. ..................................................... 62 vi Table A 15 Table A16. Table A17. Table A. 18. Table A19. Table A20. Table A21 Markers selected or multiple regression analysis .............................. 63 Chart showing marker genotypes and their relationship to canning quality traits in population 2 ............................................................ 64 Chart showing marker genotypes and their relationship to canning quality traits in population 4 ............................................................ 65 Chart showing marker genotypes and their relationship to canning quality traits in population 5 ............................................................ 66 - Proposed linkage groups for population two. .................................. 67 Proposed linkage groups for population four ................................... 68 Proposed linkage groups for population five ................................... 69 vii Figure 1a. Figure lb. Figure 2a. Figure 2b Figure 2c. Figure 2d Figure 2e Figure 3 LIST OF FIGURES Parent lines exhibiting desirable canning quality (‘Seafarer’ and N81099) ....................................................................................... Parent lines exhibiting undesirable canning quality (‘Cumulus’ and ' N84004) ....................................................................................... RILs fi'om population two exhibiting desirable canning quality ...... RILs from populationtwo exhibiting undesirable canning quality .. RILs fi'om population four exhibiting desirable canning quality (top) and undesirable canning quality (bottom). ............................ RILs fiom population five exhibiting desirable canning quality ...... RILs from population five exhibiting undesirable canning quality .. Percentage of markers significantly associated with canning quality traits at both locations using data combined over years .................. 19 20 29 3O 31 32 33 35 INTRODUCTION In the United States, 75% of all dry beans (Phaseolus vulgaris) and 98% of all navy beans grown are processed. As a result of consumer preferences regarding size, color, texture and overall appearance of the canned product, processors have developed culinary standards which beans must meet. Cultivars which fail to meet such standards may be unacceptable. Breeding for canning quality is difficult for several reasons. First, canning quality is a quantitative trait, hence, it can not be evaluated until later generations, which introduces a measure of inefficiency to a brwding program. Lines which have been selected and advanced based on agronomic traits will have to be discarded if they fail to meet canning standards. Secondly, to fitlly evaluate canning quality, several component traits need to be measured. However, the array of objective and subjective tests needed to adequately assess canning quality are not practical for a large number of samples exhibiting small difl‘erences, and are costly and time consuming. One alternative to traditional selection procedures for canning quality may be marker assisted selection (MAS). With this technique, improvement of a desired trait is accomplished by selecting for markers tightly linked to the trait of interest. Molecular markers associated with quantitative trait loci (QTLs) that influence canning quality would increase selection eficiency by allowing for evaluation in earlier generations, thereby reducing the number of lines advanced, and providing a faster, less expensive and less subjective measure of canning quality. 2 Detailed genetic linkage maps have enhanced efl‘orts to identify markers associated with QTLs in crops such as tomato (Tanksley et al., 1982; Osborn et al., 1987; Martin et al., 1989) and maize (Stuber et al., 1980, 1982, 1987; Edwards et al., 1987). Fewer, detailed genetic studies have been conducted in dry beans due to the lack of available markers. The development of restriction fiagment length polymorphism (RFLP) technology has provided enough markers to construct a linkage map for common bean (Nodari et al., 1992). Although this linkage map will be useful for some genetic studies and certain breeding strategies, it may have limitations. Recent reports suggest that there is limited RFLP-based genetic diversity between commercially adapted genotypes of bean which necessitates wider crosses for mapping purposes (Chase et al., 1991; Guo et al., 1991; Nodari et al., 1992). In addition to the difficulty of identifying RFLPs among closely related genotypes, RFLP technology is time consuming and costly. Recently, Haley et al., (1994a) showed that the random amplified polymorphic DNA assay (RAPD) revealed usefisl levels of polymorphism within races of P. vulgaris and suggested that RAPD-based linkage maps for representative populations of common bean may be useful for breeding purposes. Based on the demonstrated utility of RAPD markers in common bean, the current research was conducted in order to identify RAPD markers associated with canning quality traits in three populations of navy beans. LITERATURE REVIEW Processing Quality Acceptable canning quality in dry beans is desired by consumers, processors and plant breeders, however, what constitutes ‘acceptable” varies over time and for difi‘erent consumer groups. Consumers are most aware of the texture, wholesomeness, and overall appearance of processed beans (Wassimi, et al., 1990). Adams and Bedford (1973) stated that texture can be separated into three components: adhesiveness (force required to remove material from the mouth), gumminess (energy required to disintegrate the substance) and firmness (force required to penetrate the substance). Firmness can be assessed using a Kramer, Shear Press (Food Technology Corp., Rockville, Md.) which measures the force required to bring cooked beans to point of rupture and catastrophic breakdown of individual seeds. Although this measurement does not take into consideration the other ln'nesthetic properties described for texture, it can be used to evaluate consumer acceptability as regarding mouthfeel. Ruengsakularach et al., (1994) reported a strong correlation (r = 0.97) between canned bean shear texture and pasting torque values of whole bean flour. Because the pasting test requires only 2 g dry bean solids, it may be useful for selection purposes in early generation breeding lines. Degree of splitting (tendency of beans to break apart, burst or disintegrate), clumping (adherence of individual grains because of starch or pectin exudation), processed color, uniformity and condition of the cooking broth contribute to the overall appeal of canned beans. An acceptable cooked product would have few split beans, no clumping of beans, a light amber color, uniform shape and size of individual beans, and no starch extruded into the 3 4 cooking broth. Evaluations for these traits -are generally subjective although color can be objectively evaluated using a Hunter Lab Color and Color Difl‘erence Meter (Hunter Associates, Fairfax VA). To conduct visual evaluations, canned beans are displayed on trays and rated by a panel of qualified personnel using a hedonic scale. Sample means are determined and those with standard or above standard ratings are selected. An objective measurement, such as the washed drained weight (WDWT), may also be usefirl as an indicator of visual appeal. The WDWT is measured by rinsing, draining and weighing canned samples. A low washed drained weight might be observed if excessive splitting and loss of solids occurred during processing (Hosfield, 1991). While processors are constrained by consumer expectations, they also seek beans which lend themselves to ease of preparation and greater processing emciency. Traits such as rapid and uniform seed expansion and higher WDWTs are desired (I-Iosfield, 1991). In addition to indicating an intact, desirable product, a high WDWT reduces the amount of beans nwded to fill a can to the desired volume, thereby increasing profits to processors. A washed drained weight ratio (WDWTR = WDWT/soaked bean weight) can also be calculated and can be used to rapidly compare processed bean samples. The hydration coefficient (HC) is a measure of the weight increase during soaking due to water uptake (soaked bean weight/dry bean weight). An optimum value of 1.8 indicates a well- soaked bean, whereas lower values may be less desirable for processing as longer soaking times are often necessary (I-Iosfield, 1991). Although canning quality traits are influenced by seed characteristics, they are also affected by external factors such as storage conditions, soaking procedures and processing conditions. Uebersax and Bedford (1980) found that canning quality deteriorated (higher 5 textures and browning) with increased storage time, temperature and relative humidity. Darkening of seeds during storage has been attributed to the polymerization of phenolic compounds which is enhanced by high temperatures and high humidity levels (Burr et al., 1968; Garruti and Boume, 1985). Firm textures may be attributed to intact middle larnellae and the failure of cotyledonary cells to separate during cooking (Srisuma, et al., 1989). Absorbed water and heat applied during the cooking process cause degradation of the middle lamella allowing cells to separate and soften (Uebersax and Ruengsakulrach, 1989). Beans stored at high temperature and humidity may have higher levels of certain phenolic acids which aide in the cross-linking of pectin in the middle lamella (Srisuma, et al., 1989). In seeds with intact middle lamellae, cells fail to separate and soften during processing resulting in high texture values. The presence of an intact middle lamella may also inhibit water absorption and result in low washed drained weights (Srisuma et al., 1989). Storage conditions of 75% relative humidity or lower and 20 C or lower have been shown to produce stable canning quality in navy beans (Uebersax and Bedford, 1980) Processing conditions can also affect canning quality and must approximate commercial protocols to properly assess potential varieties. Soaking is the first step in processing beans and plays a critical role in seed coat softening leading to uniform seed expansion as well as ensuring product tenderness after cooking (Hosfield, 1991). Difl‘erences in the rate of water uptake have been observed among cultivars (Deshpande, et al., 1984). Although the precise reason for such differences is not clear, the structure and composition of the seed coat, hilum and micropyle have been associated with different rates of water absorption (Agbo et al., 1987). Soaking studies by Snyder (193 6) indicated 6 that, in some bean seeds, water uptake during soaking is primarily through the micropyle and germinal area. However, Synder’s results and those of Powrie et al., (1960) suggested that in navy beans, water uptake occurs readily through the seed coat. These authors sealed the micropyle and germinal areas with beeswax or silicone grease. Therefore, differences in seed coat structure and composition among cultivars may affect the rate of water uptake. In a comparison of water uptake in small white, black and pink beans, it was observed that a loosely arranged cell structure on the raphe-side of the hilum, a deeply-grooved hilar fissure, a narrow tracheid bar and a thinner seed coat also contribute to faster water uptake (Deshpande and Cheryan, 1986). To ensure suficient water absorption during soaking, several factors must be considered: duration of soak, temperature of soak water, and composition of soak water. The length of the soaking period is critical to ensure that enough water is absorbed however, longer soaking times can result in decreased texture values (U ebersax and Bedford, 1980). Soak-water temperature and calcium content are important factors because they afl‘ect the rate of water uptake. At higher temperatures and lower calcium concentrations seeds absorb water faster (Uebersax, and Bedford, 1980). However, calcium should not be eliminated fi'om the soak water because it forms insoluble salts with pectic acid, a major constituent of the seed coat, and helps to maintain seed firmness and integrity during processing (Uebersax and Bedford, 1980). In their study, Uebersax and Bedford (1980), evaluated different soaking procedures and different calcium concentrations in the soak water for their efl‘ect on canning quality. From these studies it was determined that a two step soaking procedure (30 minute cold soak at 23 C followed by 30 minute hot soak at 88 C) with at least 50 ppm calcium gave the best results. At 7 levels lower than 50 ppm calcium, greater bean damage and gelatinization were observed whereas, excessive calcium levels restricted water uptake and caused slightly lower washed drained weight values. Although canning quality is influenced by harvest and post-harvest handling and processing procedures, there is a genetic component (Hosfield et al., 1984; Wassirni et al., 1990). The identification of difl‘erences between cultivars that arise because of genetic difl'erences should make breeding for canning quality more efficient. Selection for canning quality can be achieved by minimizing processing variables. All materials should be handled and processed in the same manner by using a standard protocol that simulates commercial processing practices. For processing navy beans, a two stage soaking procedure is the most desirable because it maximizes differences between genotypes for water uptake and softening (I-Iosfield and Uebersax, 1980). Genetics of Canning Quality Canning quality behaves as a classic quantitative trait because phenotypes are continuously distributed either because of a number of controlling genes each with a small efl‘ect or a few genes strongly modulated by environmental conditions. Because of its quantitative nature, canning quality should be evaluated for several years at more than one location which requires a large and uniform seed sample. The number of genes influencing canning quality traits is unknown with the exception of seed coat color and condition which have been extensively studied and are well characterized (Leakey, 1988). Genes controlling pigment formation are numerous and interact closely to create a diversity of colors and mottles. In navy beans, the most important color factor is the total pigment 8 enabler/suppresser gene (P gene). All genotypes with pp have white flov'vers, white seed coats and produce no pink, red, or mauve coloration in any vegetative tissue regardless of the alleles present at other color genes (Leakey, 1988). The .1 gene, (also called the “joker” gene, is important with respect to canning quality because of its efl‘ect on seed coat color and condition. Genotypes with the dominant 1.] allele produce proanthocyanidins (leucobases) which accumulate in the parenchyma layer resulting in a shiny seed coat (Leakey, 1988). The dominant J allele also results in genotypes that have darkened hilum rings, darken with aging and become increasingly indigestible (Leakey, 1988). These traits are undesirable for commercial processing or domestic use, therefore, the recessive ji genotype is preferred and has been selected for under domestication. Although seed shape is an important canning quality trait only the truncata and fastigiate seed forms have been genetically characterized. The homozygous miv miv genotype causes seeds with flattened ends (truncata) and the fast fast genotype causes seeds to be wider at one end and sloping at the other end (fastigiate) (Leakey, 1988). Both of these shapes are undesirable in navy bean cultivars where ovoid seeds weighing 16-20 g/ 100 seeds are ideal (Adams and Bedford, 1975). In addition to seed shape, seed size is important. Sax (1923) identified a gene afl‘ecting seed size in common bean which was linked to the P color locus. Johnson and Gepts (1995) have since reported that the P locus is linked to the Phs locus, which codes for phaseolin and has been correlated with seed weight. Vallejos and Chase (1991) found an isozyme marker linked to a locus (Ssz-l) that affects swd size and overcomes maternal control over seed size. This locus accounted for 30-50% of variation in seed size which suggests that there must be other loci c0ntrolling this trait. Brothers et al., (1993) reported a broad sense heritability for seed size in pinto beans ranging from 0.39 to 0.58 9 and determined that plant architecture and seed size were not associated as was previously believed. Canning quality is strongly influenced by the environment although the nature of this environmental efl'ect is disputed in the literature. Ghaderi, et al. (1984) found significant cultivar x location (G x E) interactions for clumps and splits, seed weight, surface color, hydration ratio and processed bean moisture, suggesting that cultivars did not perform consistently relative to each other in difl‘erent environments. However, Wassirni et al., (1990) found cultivar x location interactions to be non-significant but suggested that the lack of significance may have been due to the use of segregating populations (F 2 and F 3) rather than narrowly adapted, pure-line cultivars used in other studies. Significant genotype by season (G x Y) interactions for food quality have also been observed and suggest an inconsistency of cultivar responses to seasonal variation (Hosfield, et al., 1984). In contrast, practical breeding experience indicates that although variation for canning quality occurs over locations and years, ranking among breeding lines and cultivars usually does not change significantly (Kelly et al., 1994). Even so, it is still necessary to conduct evaluations over a number of locations and years to identify those cultivars with relative stability for the component traits afi‘ecting canning quality. Markers for mapping/studying Q11: Evaluating a large number of samples with small difl‘erences is time consuming, expensive and inefficient particularly if a number of canning quality traits are measured (Ghaderi, et al., 1984). In addition to the time and expense involved, assessing canning quality must be delayed until later generations when a large, uniform swd sample can be 10 obtained. This is ineficient and costly because breeders must advance lines for several generations that will be discontinued due to poor canning quality. Because traditional selection strategies for canning quality are so costly and time consuming, alternative selection strategies would be beneficial. Recently, a study demonstrated a significant association (P<0.0001) between low seed density and superior canning quality in kidney beans (Heil and McCarthy, 1992). Because density is easy to measure and requires a small seed sample, it could be a useful selection criteria when breeding for canning quality and could be used to evaluate early generation lines. Similar associations would have to be established in other market classes of dry bean before this technique would have general plant breeding utility. Another selection criterion that needs to be explored is marker assisted selection (MAS). This technique has received attention as a method for increasing selection eficiency within breeding programs. Mth this technique, improvement in a desired trait can be accomplished by indirectly selecting for a marker tightly linked to the trait of interest. Previously, the lack of useful isozyme and morphological markers limited the application of MAS, but with the development of DNA markers, such as RFLPs and RAPDs, the technique is becoming a usefill tool for breeders. DNA markers linked to qualitative traits have been found in a number of crops including common bean (Miklas, et al., 1993; Haley, et a1, 1993; Haley, et al., 1994b), tomato (Martin, et al., 1991), lettuce (Michelmore, et al., 1991), pea (Dirlewanger et al., 1994), rice (Mohan et al., 1994), oats (Penner et al., 1993) and barley (Barua et al., 1993) and several are already being used in breeding programs. While progress has been made toward identifying and utilizing markers for qualitative traits, less advancement has been made for quantitative traits. 11 The ability to detect markers associated with quantitative traits was first demonstrated by Sax (1923) who reported the association of a seed coat color marker with seed size in common bean. Other morphological markers (Rasmusson, 1935; Everson and Schaller, 1955) as well as isozyme markers (Edwards at al., 1987; Tanksley et al., 1982; Vallejos and Tanksley, 1983) have been found to be associated with QTLs in crop plants. DNA based markers such as RFLPs and RAPDs ofl‘er even more opportunities for use because of their abundance and neutral character. QTLs have already been located in various crops using RFLPs. Martin et al., (1989) found three RFLP markers associated with water use efficiency in tomato; Osborn et al., (1987) detected one RFLP marker linked to soluble solids content in tomato; Nienhuis et al., (1987) identified four RFLP markers associated with the expression of 2-tridecanone- mediated insect resistance in tomato; Abbo et al., (1992) identified several RFLP markers associated with seed weight in lentil. A genetic linkage map with easily scored, polymorphic loci uniformly distributed throughout the genome has been suggested as a prerequisite for detailed genetic studies and marker-facilitated breeding approaches (Stuber, 1992). Such maps are necessary to determine the location and effect of all QTL for a trait, develop flanking markers for more efl'lcient selection, examine epistatic relationships, and more accurately assess the phenotypic effect of a QTL. However, a detailed linkage map is not a necessity for simply ‘tagging” QTL for selection purposes. Although an RFLP-based linkage map is available for common bean it is not suitable for evaluating molecular marker associations with canning quality for two reasons: 1.) a lack of RFLP diversity among commercially adapted material of the same market class and 2.) the possibility that certain markers are restricted to specific gene pools in common bean. 12 Studies (Chase et al., 1991; Guo et al., 1991; Nodari et al., 1992) have demonstrated that because of a lack of RFLP diversity in common bean, wider crosses must be made in order to facilitate map construction. The linkage map of common bean (Nodari, et al., 1992) was constructed using crosses between genotypes from the Andean gene pool and the Middle-American gene pool. Because navy beans all trace their lineage to ancestors derived from crosses between genotypes of the Middle-American gene pool, mapped RFLP markers may not have been polymorphic among the parents selected and therefore, not useful for this study. Mildas et al., (1993) documented the problem of gene-pool- specific markers in common bean with a marker linked to the Up-2, rust resistance gene. The marker was identified using a BCst population from the Middle-American gene pool into which the Up-2 gene, fi'om the Andean gene pool, had been introduced. Although the marker was useful in Middle-American lines for identifying the gene, all Andean materials, with or without the gene, contained the marker. Although most marker-facilitated studies of quantitative traits use RFLP markers, RAPDs are also being used with increasing fi'equency. Because RFLP-based linkage maps are often developed using inter-specific crosses, they have. limited, direct application in breeding programs that utilize intraspecific variability. Foolad et al., (1993) reported that RAPD technology would produce sufficient markers to construct an intraspecific genetic map in tomato. RAPD markers are also being used to extend the genetic map for pea (Weeden, 1994) and to construct a RAPD based map in common bean (Jung et al., 1994). In addition to map construction, RAPD markers are being used to “tag”. QTLs for quantitative traits. Tagging a QTL is accomplished by establishing associations between a marker genotype and a QTL that has the desired effect on the trait of interest. Chalmers 13 et al., (1993) used doubled haploid populations to identify RAPD markers linked to QTLs controlling the milling energy requirement of barley. Abbo et al., (1992) found RAPD and RFLP markers linked to seed weight in lentil. In common bean, Haley et al., (1994a) determined that useful levels of polymorphism (3 9%) could be detected among genotypes of the same market class using the polymerase chain reaction (PCR) based RAPD assay. In addition to greater levels of polymorphism, RAPDs are easier and less cumbersome to work with than RFLPs and do not require the use of radioactive materials. Because RAPDs are useful for Tagging” loci linked to qualitative traits in common bean (Haley et al., 1993; Haley et al., 1994b; Miklas et al., 1993), this technology may prove fruitful for ‘tagging” QTLs for canning quality traits in navy beans. In light of previous arguments, it is important to note that RAPD markers identified in this study may also be gene-pool- specific, but they would be specific to the Middle-American gene pool from which navy beans derive their lineage. Gene pool specificity will become an important issue only if markers that are identified are to be used‘for selection in crosses between gene-pools or in market classes originating fiom the Andean gene pool. Regardless of the marker type used, any marker facilitated study must be designed to give consideration to type of population used, population number and size, number of markers evaluated, and the statistical analysis chosen to confirm linkages. The types of populations used vary depending on the crop and the trait to be measured. F2 populations, backcross populations, and populations of recombinant inbred lines (RILs) derived by selfing or as doubled haploids (DH) are often used. F2 and backcross populations are generally limited to use with traits that can be measured on a single plant basis whereas, traits that involve plot measurements such as yield and canning quality will require other l4 , population types (Dudley, 1993). However, F2 populations have been used in maize to establish marker-QTL associations for yield-related traits that can be measured on a single plant basis (Stuber et al., 1987). Population size can also influence the power to detect marker-QTL linkages. Beavis et al., (1994) noted that the power to detect QTLs is a function of the number of progeny analyzed. Fewer progeny will reveal fewer QTLs. In addition, if populations are small and the number of loci controlling the trait is large, the . probability of finding the same markers associated in each population is low (Beavis et al., 1994). Repeatability between populations also depends on whether the linkage phase of the marker and the QTL is the same in all populations and, if epistasis is important, the state of other alleles (Dudley, 1993). The number of markers analyzed will also influence the probability of detecting substantial associations with QTLs. Lande (1992) has shown that in a cross of two inbred lines with continued self-fertilization, the number of marker loci needed to detect substantial associations with important QTLs is not very large (Table 1). These numbers are based on the equation 2Lt + c for random mating and 4L(l-1/2') + c for complete selfing. In these equations, L is the total recombination map length in Morgans, t is the number of generations alter the F2 or 8; generation, and c is the gametic number of chromosomes. Many difl‘erent approaches have been suggested for marker-QTL analysis. However, most methods fall into two categories: 1.) consideration of marker loci one-at-a time or 2.) consideration of all marker loci at once. When considering loci one at a time, simple F tests are appropriate if only two marker genotypes are present as in backcross or R1 populations (Dudley, 1993). The one-at-a-time approach has several limitations as 15 noted by Lander and Botstein (1989). If the QTL does not lie at a marker locus, more progeny may be needed to detect marker-QTL association and the phenotypic efl‘ect of the QTL may be underestimated. In addition, this approach cannot distinguish between a tight linkage to a QTL with a small effect and a loose linkage to a QTL with a large efl‘ect. Interval mapping, using a maximum likelihood approach has been proposed as a method to overcome such difficulties (Lander and Botstein, 1989). For interval mapping a predetermined log of the odds ratio (LOD) score is used to establish regions, associated with markers, that are likely to contain a QTL. The LOD score is the ratio of two maximum likelihood estimates and indicates how much more probable it is that the data arose from the presence of a linked QTL than the absence of a linked QTL. For example, a LOD score of 3.00 would mean that linkage between the marker in question and a QTL is 1000 times more likely than the assumption of no linkage. One-at-a-time methods have been compared with the interval mapping method (Stuber et al., 1992; Bubeck et al., 1993) and both methods showed virtually the same results in detecting QTLs. Another alternative is a combination of one—at-a-time analysis and multiple regression analysis. In this method, markers are analyzed individually using F tests and then models including significant markers are analyzed by the General Linear Model procedure. Markers which are significant in this analysis are included in the combined model (Dudley, 1993). Regardless of the method of analysis, an appropriate probability level for significance must be determined. Lander and Botstein (1989) suggest a genome dependent error rate of 0.001 while in most studies, the significance of association is based on a comparison-wise error rate of 0.05. Although false positives will likely be identified with a relaxed error rate, comparisons of possible QTLs across environments and populations will be more fruitfill. 16 Table 1. Minimum numbers of randomly placed molecular marker loci for the likely detection of substantial amociations with important QTLs at difierent times after crossing two inbred lines in typical diploid. tetraploid and hexaploid crop plants (adapted from Lande, 1992). Generations since hybridization . 1 5 10 Map length No. of Breeding Minimum number of markers needed to detect Mus) chromosomes system important QTLs 10 10 Outcrossing 30 110 210 20 20 Outcrossing 60 220 420 30 30 Outcrossing 90 330 630 10 10 Selling 30 49 50 20 20 Selling 60 98 100 30 30 Setting 90 146 150 l7 Bubeck et al., (1993) explain that a marker significant at 0.001 in one environment may be significant at only 0.05 in another environment. In this case, a relaxed Type I error rate (falsely accepting a marker-QTL association) reduces the Type 11 error rate (rejecting a true marker-QTL association). After marker-QTL associations have been established, their usefulness in a MAS strategy must be assessed. The value, ease, and cost of measurement and the genetic control of the quantitative trait will determine if MAS is efl‘ective and eflicient. If a trait is dificult and expensive to evaluate, controlled by a large number of genes with small effects, or highly influenced by the environment MAS may be more emcient than traditional selection based on phenotype (Dudley, 1993). Linkage distance between the QTL and marker is also important. For MAS to be efl‘ective, recombination between the marker and QTL must be minimized by using markers tightly linked to the QTL or markers flanking the QTL. Heritability is another factor that affects the emciency of MAS. When heritability is low or when the proportion of the additive genetic variance explained by the marker loci exceeds the heritability of the trait, marker-assisted selection is more emcient than phenotypic selection (Lande et al., 1990). Although the long-term goal of this research was to establish a MAS protocol for canning quality in navy beans, the immediate objective was to identify RAPD markers associated with canning quality traits. The procedures used to identify markers associated with canning quality traits are discussed and markers that are identified are evaluated for use in MAS. MATERIALS AND METHODS Plant Materials The visual characteristics evaluated (degree of split and clumped beans, soft vs firm appearance, surface color, brine color and degree of starch particles present, and seed size and shape considerations) are part of the standard evaluation for navy beans practiced at Michigan State University. Parent genotypes for crosses were chosen to represent extremes for canning quality in navy beans based primarily on visual appearance characteristics. ‘Seafarer’ and N81099 are navy beans that exhibited good canning quality over a ten year period while ‘Cumulus’ and N84004 are genotypes that consistently can poorly (Fig 1). ‘Seafarer’ and ‘Cumulus’ are determinate, bush-type, navy bean cultivars whereas N84004 and N81099 are upright, indeterminate, advanced breeding lines developed at Michigan State University. In 1988, a diallel cross was made among parents with good canning quality (including ‘Seafarer and N81099) and parents with inferior quality (including ‘Cumulus’ and N84004). Three populations were derived from this diallel to be used to identify RAPD markers associated with several canning quality traits. Populations of recombinant inbred lines (RILs) were developed fi'om the crosses N84004/’Seafarer’ (population 2), N84004/N81099 (population 4), and N81099/’Cumulus’ (population 5). Individual F2 plants were advanced, using single seed descent, through the F4 generation with plants grown in the greenhouse and at the MSU Botany Farm, East Lansing, MI. Moderate levels of field selection during this period eliminated progeny that were not adapted to Michigan growing conditions. F5 seed was planted at a rate of 25 18 19 O 9 , , ‘ a a '. t- r-foge'etzs era-‘- 1' a. T I- “ 2: ‘O/' 2:. ‘ . I ' ,3 . “'2‘. ‘.o’- Figure 1a. Parent lines exhibiting desirable canning quality (‘Seafarer’ and N81099). 20 Figure lb. Parent lines exhibiting undesirable canning quality (‘ Cumulus’ and N84004). g 21 seeds per row at the Bean and Beet Research Farm, near Saginaw, MI during the summer of 1992. Single plants were selected from each line and the F55 seed was increased in a winter nursery in Puerto Rico (1992/1993). A sub-sample was also gown in the geenhouse to be used for DNA extraction. Field Daigns Fm RILs were gown at two locations (Bean and Beet Research Farm, near Saginaw, MI and MSU Botany Farm, East Lansing, MI) during the summer of 1993 and F5, RILs were gown at the same two locations in 1994. Prior to planting the seeds, they were treated with Captan, Lorsban and Streptomycin sulfate, a combination treatment of fungicide, insecticide, and bacteriocide, respectively. Soil at the Saginaw location is a Misteguay (fine, mixed, calcareous, mesic Aeric Haplaquepts) and has an average pH of 7.7. Sumcient levels of exchangeable potassium are present therefore, no potash is recommended for the production of dry beans at the Bean and Beet Farm (Christenson, 1993). Fertilizer (179 kg/hectare of 21-7-0 + 4% Mn + 1% Zn) was applied during planting. To control weeds, metolachlor (2 kg/hectare) and EPTC (3 kg/hectare) were applied before planting and plots were cultivated and hand-hoed as needed. Plots were also sprayed, prior to flowering, with dimethoate (1 kg/hectare) to control leaf hoppers. At East Lansing, soil is classified as Capac (fine-loamy, mixed, mesic Aeric Ochraqualfs). At the Botany Farm a 19-19-19 fertilizer was applied during planting at a rate of 223 kg/hectare and herbicides were applied as pre-plant incorporated (ppi) (EPTC 2 kg/hectare; trifluralin 1 kg/hectare; metolachlor 2 kg/hectare). Plots were cultivated 5 22 weeks after planting, hand-weeded throughout the summer and sprayed twice prior to flowering with dimethoate (1 kg/hectare) to control leaf hoppers. Populations 2 and 5 were planted in 5x6 lattice desigrs (30 plots/replication) and population 4 was planted in a 6 x 7 lattice design (42 plots/replication). Three replications of each population were planted. Each plot consisted of two 6.1-m rows planted 50.8 cm apart at a seeding rate of 13 seeds/m. For each RIL, days to flowering, gowth habit, and plot yield were recorded for firture selection purposes. When plants were mature, 4.3-m sections fiom the middle of both rows in each plot were harvested and threshed. Processing Procedures and Quality Evaluations Harvested seed was rolled to remove debris and hand cleaned to remove split, damaged, diseased, and discolored seed. Seed moisture percentage was determined on 250 g samples using a Burrows (Model 700) digital moisture computer. Duplicate samples from each plot at each location were adjusted to 100 g solids based on moisture content (% moisture) and placed in nylon mesh bags. Mesh bags were placed in a cold soak (distilled water adjusted to 100 ppm calcium at 21 C) for 1/2 hour and then blanched in water containing 100 ppm calcium at 88 C. Blanched beans were cooled in water for 5 minutes, drained for 10 minutes, poured into coded cans (size 303 x 406) and weighed to determine the soaked bean weight (SBWT). Cans were filled with boiling brine (1.25% sodium chloride, 1.57% sucrose, 100 ppm calcium), exhausted, sealed and processed in a retort without agitation for 45 min at 116 C. After thermal processing, the cans were cooled, inverted and stored at least two weeks prior to evaluation. The following traits were evaluated for each RIL and parent line from two replications at both locations: 23 1. Soaked Bean Weight (SBWT) = weight of sample after hot soak 2. Hydration Coeficient (HC) = SBWT/fresh weight 3. Washed Drained Weight (WDWT): Processed beans were opened and decanted on a number 8 mesh sieve, rinsed in cool tap water and drained for 2 min at a 15° angle. The weight of each sample was recorded (WDWT). 4. Texture (TXT): 100g samples of processed beans were placed in standard multiblade shear compression cell and their textures determined using a Kramer Shear Press. Peak heights were converted to Newtons using the following equation: W x 1 kg x peak force x 9.8 = Newtons/100 g 100 2.04 lbs *transducer force = 3000 lb range = 1/10 5. Percent Solids Lost (SL): 100g samples of textured beans were oven dried and then weighed. Solids lost were computed using the following equation: {100 g solids - (WDWT)(dry weight)/100g cooked beans} x 100 6. Visual Appeal (VIS): Processed beans were opened and the contents placed into Styrofoam containers. A panel of qualified personnel used a 7 point hedonic scale to rate the samples. The VIS trait was averaged across judges for each sample. The seven point hedonic scale was: 1= Very undesirable 2= Moderately undesirable 3= Slightly undesirable 4= Neither desirable nor undesirable 5= Slightly desirable 6= Moderately desirable 7= Very desirable DNA Extraction and RAPD Protocol One young trifoliate leaf was harvested, from six plants of every parent line and six plants of every F55 RIL. Tissue was lyophilized, gound and stored at -80 C. DNA was extracted using a protocol outlined by Saghai-Maroof et al., (1984) with slight 24 modifications. Chloroform:isoamyl alcohol (24:1) was used in place of chloroformzoctanol, RNAase A was added prior to a second chloroformzisoamyl alcohol extraction, and DNA was resuspended in Tris-EDTA bufl‘er (TEN). In some cases, DNA that was recalcitrant to PCR (polymerase chain reaction) amplification was dissolved in a high-salt solution and re-precipitated in ethanol to remove polysaccharides (Fang, et al., 1992). DNA fi'om parent lines was amplified by PCR using 390 difl'erent, random, decamer primers (Operon Technologies, Alameda, CA) to identify primers that generated polymorphic bands. Primers were coded using a capital letter to indicate the kit used, an Arabic number to indicate which. primer in the kit was used, and in some cases a lower- case letter was used to indicate which band was scored (t= top band, m = middle band, b=bottom band). Total reaction volume was 18.8 ul and each reaction contained the following: 19 ng of genomic DNA template and 19 ng of single decamer primer (Operon Technologies, Alameda, CA), 2 units of Stoffel F ragnent polymerase (Perkin Elmer Cetus, Norwalk, CT), 1X Tris bufi‘er (10 mM Tris-HCl, pH 8.3; 10 mM KCl), 5 mM MgC12, 200 uM of each dNTP (Perkin Elmer). Reaction components were overlaid with 25 ul of mineral oil and placed in a Perkin Elmer Cetus DNA Thermal Cycler 480. Cycling conditions were: 3 cycles of 1 min/94 C, 1 min/35 C, 2 min/72 C; 34 cycles of 10 s/94 C, 20 s/40 C, 2 min/72 C; 1 cycle of 5 min/72 C; 1 s “Auto-segment extension” (for extension portion of reaction). Amplified DNA was resolved by electrophoresis (1.4% agarose gel, 0.5 ug ml'l etlridium bromide, 40 mM his-acetate, and 1 mM EDTA) and each gel was photogaphed with Polaroid film. Primers yielding polymorphisms between N84004 and Seafarer (31 primers), N84004 and N81099 (36 primers), and N81099 and Cumulus (34 primers) were screened against the respective populations. RILs were scored 25 for the presence (2) or absence (1) of the marker band. The number of markers scored for each population was: population 2— 31 markers, population 4-- 36 markers, population 5- 34 markers. Statisa'cal Analysis Each of the measured traits was analyzed by the analysis of variance (AN OVA) procedure with a factorial arrangement of treatments. The MSTAT computer program was used (model number 17). Data from individual RAPDs were then analyzed against each of the measured traits (VIS, TXT, HC, WDWT, SL) using the statistical progam SAS proc glm (SAS Insititute, 1988). The probability level for acceptance of marker-QTL association was P<0.05. In each population, traits were analyzed for each RIL for separate locations and years (designated: loclyrl, loc2yr1, loclyr2, loc2yr2), locations combined within years (designated: yearl , year2), locations combined over years (designated: locl, loc2), and combined over locations and years (designated: comb). To determine whether the presence or the absence of the marker band was associated with a desired trait, data combined over years and locations were analyzed using a one-way ANOVA (MSTAT). MAPMAKER was used to establish linkage goups (LOD score=3.00; centimorgan distance threshold=15 cM). In each population, markers associated with canning quality traits (P<0.05) at both locations or in both years were used for multiple regession analyses where R2 indicated the phenotypic variation accounted for by the markers (SAS Institute, 1988). Significant markers were used in their respective populations for selection and a composite of markers fiom all three populations was used to select lines from each population. Markers for each trait were 26 first tested for their ability to select the better canning parent in each population and then for their ability to select the RILs with the most desirable canning quality fi'om each population. In order for a line to be selected it was required to have geater than one-half of the markers for the trait being considered. Data were recorded for the number of lines selected, average visual score of selected lines, percent of selected lines scoring above 3.50 for visual appeal and range of visual scores for selected lines. Visual appeal scores averaged across locations and years were used in all cases. Selection using markers fiom each population in their respective populations was compared with selection using a composite of markers fi'om all three populations. In addition, selection based on a combination of visual and texture markers was compared with selection based on visual markers alone. Heritability estimates were calculated on an entry mean basis for VIS, TXT, and WDWT using the formula: hzgozc/O’z'r 02¢; = genotypic variance 0’: = total variance among means of RILs compared in r replications, I locations and y years(r=2, l=2,y=2) Variance components were estimated from the analysis of variance by appropriate algebraic manipulation of terms comprising the expected values (Allard, 1960). A random model was used (Table Al - A9). Total variance was calculated using the formula: 021': 020+O’cy/y‘l'O'IGL/14'OJGLYlly+0fllrly 27 Correlations were computed for the following pairs of traits: VIS:WDWT, VIS:SL VIS:HC, VIS:TXT, WDWT:SL, and TXT2HC. Correlation coefiicients were compared with marker trends across traits. RESULTS Within each population there was obvious variation between the lines for canning quality particularly for visual appeal (Fig 2a,b,c,d,e). For all of the measured traits, significant genotypic differences existed in each of the populations (Table 2). Location effects were also siglificant for all traits, in all populations with the exception of VIS in population five. Years were also a significant source of variation for all traits except VIS and SL. Interactions between G x L, G x Y, and G x L x Y were not consistently siglificant for all traits or for a given trait in all populations. Significant genotypic variation permitted the identification of several markers associated with each trait (P<0.05) in each of the three populations (Table A. 10 - A. 14). R2 values for the markers, calculated with data combined over years and locations, ranged from 0.13 - 0.29 in population two, 0.10 - 0.38 in population four and 0.13 - 0.28 in population five. Location specificity was evident as a large proportion of the markers were associated with traits at only one of the two locations (Fig. 3). Many of the markers were also population specific although a few were siglificantly associated with a canning quality trait in two of the three populations. None of the markers were associated with a trait in all three populations (Table 3). Markers selected for multiple regession analysis are listed in Table A15. R2 values ranged from 0.15 - 0.74 depending on the trait and the population considered (Table 4). Marker genotypes and their relationships to canning quality traits are shown in Tables A16.A.18. The effectiveness of indirect selection based on marker genotype varied for each population and for the subset of markers used. In population two, markers associated 28 29 Figure 2a. RILs from population two exhibiting desirable canning quality 30 Figure 2b. RILs fi'om population two exhibiting undesirable canning quality. Figure 2c. RILs fiom population four exhibiting desirable canning quality (top) and undesirable canning quality (bottom). 32 Figure 2d. RILs fi'om population five exhibiting desirable canning quality. 33 Figure 2e. RILs from population five exhibiting undesirable canning quality. 34 Table 2. Siglificant sources of variation for visual appeal (VIS), texture (TXT), hydration coefiicient (HC), washed drained weight (WDWT), and percent solids lost (SL) in population 2 (PZ), population 4 (P4) and population 5 (PS). Traits VIS TXT HC WDWT SL Populations Source P2 P4 P5 P2 P4 P5 P2 P4 P5 P2 P4 P5 P2 P4 P5 Year (Y) ns us it 0‘ it it it t. fit it t it #0 n5 n8 Mon (L) .0 it [IS I. it it it 0 it it t. I. .0 t O. Y X L us it t fit .0 it ti as it it t. it t t. t Reps/(YL) IIS it fit it #0 ns t it fit I. it it it it it Genmm (G) I. t. t. it it O. i *3 II t. t. .0 O. t t G X Y t t it it it fit us it us it t it [IS ns as G X L as it it t. it 0‘ t 118 us it us it ns ns t G X L X Y us it it it it #0 #fi us it it us it I ns ns "' P<0.05 " P<0.01 ns = non significant 35 Initial.) ‘ urn (b) Inc (e) IWDWNd) ISL (a) Figure 3. Percentage of markers significantly associated with canning quality traits at both locations using data combined over years. Table 3. Markers siglificantly associated with canning quality traits in two of the three 36 navy bean populations. Canningguality trait Marker Population 2 Population 4 Population 5 Vrsual Score Q11 Significant Significant M11 Significant Significant Hydration coefficient C5 Significant Significant M10 Significant Significant N17 Significant Significant X3 Significant Significant 016 Significant Significant Y13 Significant Significant Texture F5 Significant Significant G4 Significant Significant Washed drained weight P5 Significant Significant Y4 Significant Significant Percent solids lost M10 Significant Significant P5 Significant Significant N18 Significant Significant Yl3 Significant Siglificant AC2 Significant Sigm_fi' cant Significant at P < 0.05 37 Table 4. Proportion of phenotypic variation accounted for by selected markers using multiple regession. Population 2 Population 4 Population 5 No. of No. of No. of Trait markers R2 markers R2 markers R2 Visual score 1 0.20 6 0.50 4 0.52 Texture 3 0.39 3 0.29 5 0.40 Hydration coefl'rcient 2 0.15 5 0.74 6 0.65 Washed drained weight 6 0.42 0 ~— 3 0.38 Percent solids lost 3 0.35 8 0.52 2 0.31 using data combined over years and locations 38 with high HC and WDWT values and low SL values caused the inferior canning parent (N 84004) to be selected over the superior canning parent (‘Seafarer’). Markers for high VIS and TXT values caused ‘Seafarer’ to be selected over N84004. When the markers developed from population two were used for selection in population two, markers associated with VIS were best for identifying the superior RILs (based on visual score). Lines selected using VIS markers had an average VIS score of 3.9 and individual line scores ranged fiom 3.4 to 4.5 (range = 1.1). Eighty-one percent of the selected lines scored above 3.50 for visual appeal. When markers for the other traits were used, selected lines had lower average VIS scores, larger ranges for VIS scores, and fewer scored above 3.50 (Table 5a). The composite of VIS markers from all three populations was not as effective at selecting the best canning lines fi'om individual populations as the VIS markers used in the populations fi'om which they were identified (Table 5b). The average VIS score for all selected lines was 3.7 and individual line scores ranged from 2.7 - 4.5 (range = 1.8). Seventy-seven percent of the selected lines scored above 3.50. In population four, markers associated with all traits except a high HC identified the superior canning parent (N 81099). When markers developed in population four were used for selection in population four, markers for VIS and TXT were best able to identify the lines with high VIS scores (Table 6a). However, lines selected using TXT markers had a wider range of VIS scores and had scores below 3.00. The average VIS score for lines selected using VIS markers was 3.6 and individual line scores ranged fi'om 3.1 to 4.2 (range = 1.1). Of the selected lines, 47% scored above 3.50. The average VIS score for lines selected using TXT markers was 3.6 and individual line scores ranged from 2.9 - 4.2 (range = 1.3). Of the selected lines, 63% scored above 3.50. When the composite of 39 Table 5a. Efi‘ectiveness of selected markers for visual appeal (VIS), texture (TXT), hydration coeficient (HC), washed drained weight (WDWT), and percent solids lost (SL) for identifying recombinant inbred lines with high visual scores in population two. Range of visual scores No. and percent of selected Marker No. of lines Average visual score of for selected lines scoring above 3.50 for ype selected selected lines lines visual score V18 11 3.9 1.1 9/11 =81% TXT 9 3.5 2.1 6/9 =66% HC 7 3.7 1.0 4/7 857% WDWT 11 3.6 2.1 7/11 =64% SL 15 3.6 2.1 8/15 =53% Table 5b. Efl‘ectiveness of a composite of markers for visual appeal (VIS) fi'om three populations for identifying recombinant inbred lines with high visual scores in population two. ' Range of visual scores No. and percent of selected Marker No. of lines Average visual score of for selected lines scoring above 3.50 for type selected selected lines lines visual score VIS 13 3.7 1.8 10/13 = 77% 40 VIS markers was used for selection, the results were less desirable (Table 6b). The average VIS score for selected lines was 3.4 and individual line scores ranged from 2.4 - 4.2 (range = 1.8). Only 35% scored above 3.50 for visual appeal. In population five, the superior canning parent (N 8 1099) was selected over the poor canning parent (‘Cumulus’) when markers for all traits, except a high TXT value, were used. Using only markers developed from population five for selection, the best results were achieved with markers for high VIS scores (Table 7a). The average VIS score of lines selected with VIS markers was 3.4 and individual line scores ranged fi'om 2.7 - 3.9 (range = 1.2). Of the selected lines, 43% scored above 3.50 for visual appeal. Selection based on markers for other traits gave lower average scores, wider. ranges for individual line scores and fewer lines scoring above 3 .50. The composite of VIS markers was less efl‘ective for selecting lines with high VIS scores (Table 7b). Average VIS score for selected lines was 3.1 and the range of individual line scores was 1.6 - 3.9 (range = 2.3). Only 23% scored above 3.50 for visual appeal. Selection was more stringent but also more accurate, when only those lines that were selected by the composite of VIS markers and by the composite of TXT markers were considered. In all three populations, the number of lines selected was lower, the average score of selected lines was higher, the range of VIS scores was smaller, and a geater percentage of the selected lines scored above 3.50 (Table 8). Heritability estimates for VIS scores, TXT values and WDWT values were moderate to high (Table 9). Results fi'om the linkage analysis allowed markers to be assigned to five linkage goups in population 2, eight linkage goups in population 4 and six linkage goups in population 5 (Table A. 19 - A21). The largest estimated distance 41 Table 6a. Effectiveness of selected markers for visual appeal (VIS), texture (TXT), hydration coefl'rcient (HC), washed drained weight (WDWT) and percent solids lost (SL) for identifying recombinant inbred lines with high visual scores in population four. Range of visual scores No. and percent of selected Marker No. of lines Average visual score of for selected lines scoring above 3.50 for type selected selected lines lrnes visual score V18 19 3.6 1.1 9/19 = 47% TXT 8 3.6 1.3 5/8 = 63% BC 19 3.3 1.7 6/19 - 32% SL 10 3.4 1.3 4/10 = 40% Table 6b. Effectiveness of a composite of markers for visual appeal (VIS) fi'om three populations for identifying recombinant inbred lines with high visual scores in population four. Range of visual scores No. and percent of selected Marker No. of lines Average visual score of for selected lines scoring above 3.50 for type selected selected lines lines visual score ‘ V18 31 3.4 1.8 11/31 = 35% 42 Table 7a. Efl‘ectiveness of selected markers for visual appeal (VIS), texture (TXT), hydration coefiicient (HC), washed drained weight (WDWT), and percent solids lost (SL) for identifying recombinant inbred lines with high visual scores in population five. Range of visual scores No. and percent of selected Marker No. of lines Average visual score of for selected lines scoring above 3.50 for type selected selected lines lines visualscore V15 7 3.4 1.2 3/7 =43% TXT 15 2.9 2.3 3/15 = 20% KC 8 3.1 1.7 2/8 =25% WDWT 12 2.6 1.5 1/12 -= 8% SL 8 2.7 1.6 0/8 = 0% Table 7b. Efi‘ectiveness of a composite of markers for visual appeal (VIS) fi'om three populations for identifying recombinant inbred lines with high visual scores in population five. Range of visual scores No. and percent of selected Marker No. of lines Average visual score of for selected lines scoring above 3.50 for type selected selected lines lines visual score V18 13 3.1 2.3 3/13 = 23% Table 8. Efl‘ectiveness of selection based on a composite of markers for visual appeal (VIS) and texture (TXT) from three populations. Rangeof No.andpercentof visualscores selected linesscoring Marker No. of lines Avg. visual score of of selected above 3.50 for visual type Population selected selected lines lines score VIS:TXT 2 5 3.9 0.5 5/5 = 100% VIS:TXT 4 l 4.2 1/1 -= 100% VIS:TXT 5 10 3.6 2.3 3/10 = 30% 43 between linked markers was 8.7 cM in population 2, 14.4 cM in population 4 and 8.7 cM in population 5. Correlations between the following traits, VIS and WDWT, VIS and SL, VIS and TXT, VIS and HC, WDWT and SL, TXT and HC, were not high enough to establish strong associations although certain trends were observed (Table 10). There was a negative relationship between VIS and WDWT. Correlations ranged fi'om -0.26 to -0.66 with one non-siglificant value (1994, population 4). VIS and TXT seemed to be positively associated with correlations ranging fi'om 0.19 to 0.66. WDWT and SL lost also tended to be negatively associated (correlation = -0.22 to -0.90) with the exception of population four data from 1993. Markers that were significantly associated with more than one trait reflected these trends in most cases. Only one marker (Q11 in population five) was significantly associated with VIS and WDWT but it demonstrated a negative relationship between the traits. Selection for high VIS required the presence of the Q11 band whereas selection for high WDWT required its absence. One marker (N 18b fiom population four) was significantly associated with VIS and TXT and it reflected the positive correlation between the two traits. Selection for high VIS and a high TXT value both required the absence of the N18b marker band. Correlations between traits were not as evident when goups of markers were considered. In population two, 11 lines were selected with population two-derived VIS markers. Only 2 of those 11 lines were selected when TXT markers from population two were used and 5 of the 11 were selected when WDWT markers were used. When the composite of markers was used, 13 lines were selected based on VIS markers. Five of these thirteen lines were selected based on TXT markers and 5 lines were also selected Table 9. Heritability estimates for visual appeal (VIS), texture TXT) and washed drained weight (wnwn. Trait Population 2 Population 4 Population 5 Mean across populations VIS 0.48 0.55 0.66 0.56 TXT 0.92 0.96 0.59 0.82 WDWT 0.72 0.62 0.67 0.67 Table 10. Correlation coefficients between canning quality traits in three populations of navy beans. Population 2 Population 4 Population 5‘ Cumu- 1993 1994 Cumu- 1993 1994 Cumu- 1993 1994 Correlations lative lative lative viszwdwt 0.58“ -0.66*"' -0.5 l " -0.26“ -0.49" NS -0.33"‘I -0.39‘"" -0.45" viszsl 0.14‘I 0.21“ NS -0.12‘ -0.31“ NS NS 0.19" NS vis:txt 0.49“ 0.66" 0.46" 0.22“ 0.33“ 0.19“ 0.42" 0.43“ 0.29“ viszhc -0.14‘ -0.32” 0.20‘I NS NS NS 0.19“ NS NS txtzhc NS -0.42“ 0.45" 0.28"”I NS 0.34" 0.14“ NS NS wdwtzsl -0.53" -0.50" -0.55" -0.52""" 0.27“ 41.90” -0.23" -0.2.‘3‘"‘I -0.22" ‘ P<0.05 “P<0.01 NS = non significant 45 . based on markers for WDWT. In population four, 19 lines were selected with population four—derived VIS markers. TXT markers fi'om population four permitted selection of 7 of these 19 lines. When the composite of markers fi'om all three populations was used, 31 lines were selected based on VIS markers. Only one line was selected using TXT markers but it was a line also selected using VIS markers. Markers for WDWT were used to select 18 of the 31 lines that were selected when VIS markers were used. VIS markers specific to population five, permitted selection of 7 lines from population five. Of these 7 lines, 6 were also selected when TXT markers from population five were used. In contrast, when WDWT markers were used only 1 of the 7 lines selected using VIS markers was chosen. When the marker composites were used for selection in population five, 13 lines were selected based on VIS markers, 10 of which were also selected when TXT markers used. Three lines were selected based on WDWT markers, none of which were selected when VIS markers were used. DISCUSSION Although most quantitative traits are influenced by the environment, many of the studies associating QTLs with marker loci have been conducted using only one environment. While this practice simplifies the analysis and reduces the demands on time, resources and money, it does not allow marker-QTL associations to be tested in different environments. This may lead to poor decisions when choosing markers for MAS. Marker studies that have been conducted at multiple locations have identified environment-specific marker-QTL associations (Bubeck et al., 1993; Patterson et al., 1991). The location specificity of markers for canning quality traits, previously described, was not surprising because it is common for the canning quality of a genotype to vary from location to location and because the analysis of variance indicated that location x genotype interactions were statistically significant for many of the traits in each population. One possible explanation for the difi‘erence in canning quality across locations could be environmentally-sensitive QTLs. This would also explain the location specificity of the marker-QTL associations. Markers for QTLs that function consistently at a number of locations would be preferable for MAS. However, location-specific markers may also be useful. Testing at several locations is commonly practiced in order to identify genotypes that perform well over a range of environments. By pyramiding location-specific markers into one genotype, it may be possible to achieve the same results at a faster rate (Patterson, et al., 1991). 46 47 Another issue that affects the usefulness of marker-QTL associations is population specificity. Many of the marker studies that have been conducted utilize only one population, which may also lead to poor choices or markers for MAS. Population-specific marker-QTL associations were prevalent in this study but were expected because of small population size. However, small populations were unavoidable due to the method of population development that was utilized and the elimination of unadapted lines. Small population sizes (27, 37, and 26 RILs in populations two, four and five respectively) and a large number of genes influencing canning quality may be one reason for the population specificity of the markers. When fewer progeny are analyzed, fewer QTLs can be identified (Beavis et al., 1994). Therefore, if the ability to detect QTLs is reduced because of small population size and the number of QTLs is large, the probability of detecting the same QTLs in difl‘erent populations is small. Beavis et al., (1994) demonstrated a similar anomaly when the QTLs they found associated with yield in maize differed fi'om those found by Stuber et a1. (1992) using progeny derived fiom the same pair of parent lines. However, the two experiments were conducted at different locations so it is possible that environmentally sensitive QTLs contributed to the difi‘erences. Other possible causes of population-specific marker-QTL relationships are large linkage distances between the markers and the QTLs and epistatic interactions. If the distance between the markers and QTLs is sufficiently large, recombination may occur resulting in the markers being separated from the QTLs in some individuals or entire populations. If epistatic interactions are important for the expression of the QTLs, recombination between the QTLs and other loci influencing the QTLs may result in different population specificities of the marker-QTL associations. In this case, although the marker may still be linked to 48 the QTL, an individual or population may not have the other necessary genes present, in . the appropriate state, for the QTL ,to be adequately expressed. Thus, in a statistical analysis the marker would not be associated with the trait of interest. All of these possibilities would need to be considered when deciding how to use population-specific markers. Obviously, the absence of population-specific marker-QTL associations would be more useful for MAS. However, population-specific markers may still be useful if population specificity is due to small population size and a number of controlling genes rather than large linkage distances and epistasis. If that is the case, using population- specific markers to pyramid QTLs may result in lines that have more favorable alleles for the desired trait. Whether or not the difficulty of such a task outweighs the benefits needs scientific scrutiny. Another factor that influences the eficiency of MAS is the heritability of the desired trait. For highly heritable traits (i.e few genes and little environmental influence), MAS ofi‘ers no geater selection efliciency than phenotypic selection except when MAS allows for earlier evaluation of a trait than does phenotypic selection. For traits with low heritabilities MAS would be more eflicient than phenotypic selection if the markers explain a large proportion of the additive genetic variation (Lande, 1990). Canning quality can be viewed as a “super” trait because no single variable can adequately describe the characteristics of a sample. One needs to look at canning quality through dissection into a number of defined characters that can be individually measured. These individually measured characters or components of canning quality are heritable but act as quantitatively inherited traits when they are measured. Because the components of canning quality behave as quantitative traits, substantial environmental influence on 49 canning quality was expected and has been documented (Hosfield, et al., 1984; Ghaderi et al., 1984). It was interesting that components of canning quality were so highly heritable, indicating limited environmental variance. It was also interesting when the results of the marker analysis were considered. Markers that were significantly associated with each of the measured traits were often location specific, suggesting environmentally-sensitive QTLs. Therefore, one would expect the environment to have a strong influence on the expression of these traits, resulting in lower heritability estimates than those that were calculated. One possible reason for the high heritability values is that evaluations were conducted at only two locations for two years. Heritability values may have been lower if evaluations had been made for additional locations and years. It is also possible that canning quality traits are controlled by a few major genes with large environmental sensitivities rather than a large number of genes with small effects. If this is the case, one would expect moderate to high heritability values for TXT and WDWT but would expect the heritability of VIS to be lower than that of TXT or WDWT. This is because VIS is a subjective measurement which is influenced by the perception of the following traits: the amount of clumping and splitting of processed beans; cooking broth characteristics; and cooked seed characteristics such as color, size and shape for the market class. VIS would therefore be governed by the genes influencing the component traits, each with their own particular environmental sensitivities. The heritability for VIS would be lower than for the individual components if each were measured. As observed in all three populations, the heritability of VIS is lower than the estimates for TXT and WDWT. An accurate assessment of the effectiveness of the identified markers for MAS is beyond the scope of this study. However, selecting among the three populations gave an 50 approximation of how well these markers were able to identify lines with high visual scores and may have implications for traditional breeding strategies. Markers for VIS were best for selection purposes in all populations. However, when the composite of markers for VIS was used, more lines were selected and fewer of the selected lines had acceptable VIS scores. Although this illustrates the difiiculty of using population-specific markers to make selections in other populations it does not eliminate the possibility of using these markers for MAS. Because canning quality is not evaluated until later generations, the result is a mixture of superior and inferior lines in regards to this trait that have to be evaluated by prescribed pilot plant methodologies at later generations. Through the use of these markers, one should be able to separate lines that would be unacceptable fi'om those that would have acceptable canning quality. However, based on the preliminary MAS studies some lines with unacceptable canning quality would be selected. Thus the major advantage of MAS, as opposed to phenotypic selection, for canning quality is that MAS can be done as early as the F2 generation. Early generation selection would reduce the number of lines that would be advanced to the point of consideration for release as cultivars. It is important to note that even if MAS is utilized, it will still be necessary to process selected lines using a simulated commercial processing protocol before they are released as cultivars. Using a combination of markers for VIS and TXT may also increase the number of selected lines with acceptable canning quality and reduce the number of selected lines with unacceptable quality. However, it may be necessary to relax the selection criteria to be sure enough lines are advanced. The relative eficiency of marker assisted selection, using the markers identified in this research, compared to that of traditional phenotypic selection is a worthwhile research objective. 51 In a breeding program, lines that have been proven to exhibit superior canning quality are often used repeatedly in crosses designed to combine canning quality with other desirable traits. Population specific markers could be used to facilitate this breeding practice. For example, markers associated with high VIS scores in population two (‘Seafarer’lN 84004), were all present in ‘Seafarer’. Therefore, these markers could be used to select for canning quality among progeny from crosses between ‘ Seafarer’ and various breeding lines. Used in this fashion, population specific markers may have long- term utility in a breeding progam. Most dry bean breeders select for canning quality by visual assessment alone. The results of the current research seem to validate such a practice. Whether selection is done with markers or by phenotypic evaluation, one is selecting for QTLs with favorable effects on the trait of interest. If selection based on markers (QTLs) for VIS is more efi‘ective than selection based on markers (QTLs) for the other traits, then it would seem that phenotypic selection for QTLs with favorable effects on VIS would be more effective than phenotypic selection based on QTLs for other traits. It is still necessary to evaluate TXT, WDWT and HC but these evaluations can be made when a line is being considered for release as a cultivar. Breeding lines which deviated substantially from accepted values for the objectively measured traits would not be good candidates for release as cultivars. They may, however, be useful as parents for improving other traits in the population such as yield, disease resistance, plant architecture etc. Since there was a positive correlation between VIS and TXT, lines selected based on VIS should have acceptable TXT values . Although beans with high WDWTs are desired by processors, selecting for this trait either with markers or by gavimetric methods would not be effective in a breeding 52 program. Markers associated with high WDWT values were not as usefill as markers for high VIS for identifying lines with high VIS scores. In addition, the negative correlation between VIS and WDWT suggests that if selection were based solely on high WDWT, this procedure would have a negative effect on VIS. HCs do not usually deviate substantially from the desired value therefore, lines selected on VIS alone are likely to have acceptable values for this trait. Based on this preliminary research, markers for canning quality traits may prove to be usefill tools in the process of developing navy bean cultivars with superior canning quality. Research efforts should now be directed at assessing the utility of the identified markers for MAS in other populations of navy beans as well as populations of other market classes of dry bean. SUMMARY The difiiculty of evaluating and selecting for canning quality has prompted dry bean breeders to seek alternative methods of selection. MAS is one possibility that is being explored. We have identified markers associated with several canning quality traits that may be used in a MAS scheme. Because many of the markers are location and/or population specific, which markers will be used and in what manner they will be used with geatest advantage is unclear. Markers for VIS were best able to identify good canning lines but still selected a number of poor canning lines. Selecting based on VIS markers and TXT markers increased the average score of the selected lines. However, the number of lines selected was often quite low which may necessitate reducing the number of markers required for a line to be selected. Heritability estimates for VIS, TXT, and WDWT were moderate to high but may be inflated since broad sense heritability estimates were used. Although, lower heritability values were expected, the calculated estimates may indicate that there are a few major genes controlling TXT and WDWT. Because VIS is a multi-faceted trait that is influenced by other canning quality traits, it would be controlled by more genes with difl‘erent environmental sensitivities. Thus a lower heritability would be expected for VIS than for the individual traits. High heritabilities for traits may reduce the efliciency of MAS compared to traditional phenotypic selection. In addition to heritability, the correlations between various canning quality traits will influence how effective MAS will be. Since negative correlations between VIS and WDWT were observed and initial selection attempts using markers indicate that markers 53 54 for high WDWT were not effective for selecting lines with desirable canning quality, selecting for high WDWT would be counter-productive. The best strategy appears to be selection based on visual evaluation regardless of how the selections are made (MAS or phenotypic. selection). Recognizing that other traits will need to be measured when a line is considered for release as a cultivar. Positive correlations between TXT and VIS and little variation for HC indicate that lines selected for visual appeal are likely to have acceptable values for other important traits. APPENDIX 55 Table A. 1. Form of the analysis of variance for VIS in population 2. Source Df ss MS E[MS] Year(Y) (y - 1) 0.040 0.040 Location (L) (1 - 1) 81.877 81.877 LxY (1 - l)(y- 1) 0.768 0.768 Reps/(LXY) (r - l)ly 3.819 0.955 Genotype(G) (g - 1) 77.252 2.664 o1. + r62m+ rlo‘owr ryrr’aL + rlyozo GxY (g- 1)(y- 1) 34.219 1.180 o3.+ro2m+rlo’ay G x L (g -1 )(1 - 1) 25.225 0.870 o’,+ ragga-t- ryo’m, G x L x Y (g - 1x1 - 1)(y - 1) 19.348 0.667 c’.+ ro’cM Error (r - 1)(_gly - 1) 75.683 0.652 6’. Table A2 Form of the analysis of variance for TXT in population 2. Source Df 55 MS ElMS] Year (Y) (y - 1) 1895220328 1895220328 Location (L) (1 - 1) 3223072473 3223072473 L x Y (1 - l)(y - 1) 765505.093 765505.093 Reps/(LxY) (r - 1)1y 132630.916 33157.729 Genotype(G) (g - 1) 1689453556 58257.019 o’.+ rozmar rlo’o,+ ryoza + rlyo’G o x Y (3 - 1)(y - 1) 373603.975 12882.896 61,», rozm+ rlo’.W G x L (g -1 )(l - 1) 484027.004 16690.586 o’.+ ro’ay-t- rya’ox, G x L x Y (g - l)(l - l)(y - 1) 142905.077 4927.761 o1.+ ro’m Error (r - l)(gly - 1) 724967.419 6249.719 6’. Table A3. Form of the analysis of variance for WDWT in population 2. Source Df 53 MS E[MS] Yearm (y - 1) 620.817 620.817 Location (L) (l - 1) 28754.704 28754.704 L x Y (1 - l)(y - 1) 1192.604 1192.604 Reps/(LxY) (r - l)ly 2327.492 581.873 Genotype(G) (g - 1) 5406.725 186.439 o’.+ ro3m+ fl030y+ ryo’m, + rlyo’o G x Y (g - l)(y - 1) 1015.558 35.019 o’.+ ro’m+ rlo’ay G x L (g -1 )(l - 1) 1260.296 43.458 o’.+ roams» ryo’m, GxLxY (g-1)(l-1)(y- 1) 784.646 27.057 o2.+rc’m Error (r - 1);eg - 1) 1611.258 13.890 0'2. 56 Table A4. Form of the analysis of variance for VIS in population 4. Source Df ss MS - E[MS] Year (Y) (y - 1) 1.134 1.134 Location (L) (1 - 1) 22.565 f 22.565 L x Y (1 - l)(y - 1) 5.582 5.582 Reps/(LxY) (r - 1)ly 5.476 1.369 Genotype(G) (g - 1) 79.671 - 1.992 o3. + razou+ rlozoy-t- ryo’aL + rlyo’a G x Y (g - l)(y - 1) 20.179 0.504 o1,+ ro2m+ r163“ G x L (g -1 )(1 - 1) 35.538 0.888 02,-1- rozau-t- rye’m, G x L x Y (g - 1)(1 - 1)(y - 1) 32.811 0.820 63.49 rc’m Error (r - ugly- 1) 49.029 0.306 0“. Table A5. F orm of the analysis of variance for TXT in population 4. Source Df 55 MS E[MS] Year(Y) (y -1) 962306.190 962306.190 Location (L) (l - 1) 1780250323 1780250323 L xY (1 -1)(y - 1) 315526.756 315526.756 Reps/(LxY) , (r - 1)ly 143770.317 35942579 Genotypc(G) (g - 1) 1434287275 35857.182 o3,+ razau-l- rlc’m,+ rye?“L + rlycr’G G x Y (g - l)(y - 1) 251594.315 6289.858 c’.+ rozaLY+ r163." G x L (g -l )(1 - 1) 328711.513 8217.788 63.+ rams» ryc’.ll o x L x Y (g - 1)(1 - 1)(y - 1) 275151.644 6878.791 o3,+ rc’m Error (r - 1L(_grly - 1) 405886.402 2536.790 63. Table A6. Form of the analysis of variance for WDWT in population 4. Source Df 55 MS E[MS] Year (Y) (y - 1) 183.003 183.003 Location (1.) (l - 1) 26712195 26712195 L x Y (1 - l)(y - 1) 468.488 468.488 Reps/(LxY) (r - 1)ly 17716.921 4429.230 Genotype(G) (g - 1) 7091.735 177.293 02,-!- ro‘mat I‘IO’zay'l' ryo’a,L + rlyc’a G x Y (g - l)(y - 1) 2583.247 64.581 o3,+ ro3m+ r163.”r G x L (g -l )(l - 1) 2198.430 54.961 o’.+ ro’m+ tyczm G x L x Y (g - 1)(l - 1)(y - 1) 2074.137 51.853 'o’,+ ro’our Error (r - 1)(ngy - 1) 6271.829 39.199 0’2. 57 Table A7 . Form of the analysis of variance for VIS in population 5. Source or $5 MS E[MS] Year(Y) (y - 1) 9.832 9.832 Location (L) . (1 - 1) 0.041 0.041 L x Y (1 - 1)(y - 1) 1.020 1.020 Reps/(LXY) (r - 1)1y 3.619 0.905 Genotype(G) (g - 1) 84.974 3.035 o’,+ rolm+ rlo’oy-l- ryo’m, + rlyo’a G x Y (g - 1)(y - 1) 25.257 0.902 c’.+ [Uzmy't' rlczav G x L (g -1 )(l - 1) 19.296 0.689 o’.+ ro’gu't- ryo’m, G x L x Y (g - 1)(l - 1)(y - 1) 15.439 0.551 o’.+ r020“ Error (r - 1)(_gly - 1) 25.545 0.228 6’. Table A8. F cm of the analysis of variance for TXT in population 5. Source Df 83 MS E[MS] Year (Y) (y - 1) 3068117.148 3068117148 Location (L) (l - 1) 2263606882 2263606882 L xY (1 - 1)(y - 1) 752532.771 752532.771 Reps/(LxY) (r - 1)ly 2432.593 608.148 Genotype(G) (g - 1) 3045959477 108784.267 0”. + r63m+ rlo’oyaa ryoflg + rlyo’o G x Y (3 - l)(y - 1) 991859.853 35423.566 o3,+ rczmar rlc’av G x L (g -1 )(1 - 1) 689272.804 24616.886 o3.+ rolm+ ryo’or, G x L x Y (g - 1)(1 - 1)(y - 1) 420679.962 15024.284 o’,+~rc’ai,,r Error (r - 1)(gly - 1) 654820.797 5846.614 6’. Table A9. Form of the analysis of variance for WDWT in population 5. Source Df ss MS E[MS] Year (Y) (y - 1) 823.142 823.142 Location (L) (1 - 1) 18451.556 18451.556 L x Y (1 - 1)(y - 1) 8975.211 8975.211 Reps/(LxY) (r - 1)1y 952.569 238.142 Genotype(G) (g - 1) 7963.754 284.420 o’.+ razou-i- rlo’oyer ryozm, + rlyo’a G x Y (3 - 1)(y - 1) 2229.233 79.615 o’.+ ro’m+ rlc’ay G x L (g -1 )(l - 1) 2503.569 89.413 o3.+ rozggyi- ryc’m, G x L x Y (g - 1)(1 - l)(y - 1) 2086.039 74.501 o’,+ [02913 Error (r - l)(_gly - 1) 3358.181 29.984 58 Table A. 10. Markers siglificantly associated (P<0.05) with visual score in three populations of navy beans. Combination of data used in analyses Yearl Locerl Loc2le Year2 Locer2 Loc2Yr2 Cmb' Locl Loc2 Pop. Significant markers 2 A18 A18 A18 A18 A18 A18 L18 L18 Q3 Q3 Q3 Q11 Q11 Y10 4 A14 A14 A14 A14 818 318 B18 B18 B18 C5 C5 C5 C5 H12t H12t H12b H18b 12 I2 12 I2 12 I2 12 I2 118t Il8b 19b J9b M2 M2 M2 M10 M10 M10 M11 M11 M11 M11 M11 M11 M11 N17 N17 N17 N18t N18t N18t N18m N18m N18m N18m N18b N18b N18b N18b N18b N18b 016 P16 Q11 Q11 Q11 X7 X17 X17 X17 Y3t Y3t Y3t Y3t Y3t Y3t Y5 Y5 AC2 5 B15 815 11 11 11 11 L8 L8 L8 L8 L8 M11 M11 M11 M11 M11 M19 016 016 P5 P5 Q11 Q11 Q11 Q11 X3 X3 X3 . X3 X3 Y4b Y4b Y4b Y13 Y13 Y13 'data combined over years and locations 59 Table A 1 l. Markers siglificantly associated (P<0.05) with texture in three populations of navy beans. Combination of data used in analyses Yearl Locerl Loc2le Year2 Loc1Yr2 Loc2Yr2 Cmb' Locl Loc2 Pg) Sigpificant markers 2 - F51 F51 F51 F51 F51 F51 F51 F51 F51 F5b G4 G4 G4 G4 G4 G4 G4 G4 G4 12 12 M19 N17 N17 P5 P5 P5 P5 Y4b Y4b Y4b Y4b Y4b Y4b Y4b A86 A86 AC8 AC8 4 A14 818 318 12 12 J91 M5 M5 M5 M5 N18b N18b N18b N18b N18b N18b N18b 016 X7 X7 X7 X7 X7 X17 X17 Y3t Y3b Y3b Y3b Y3b Y3b Y3b Y3b Y3b Y5 Y5 Y5 Y5 5 F51 F51 F51 F51 F51 G4 G4 G4 G4 G4 L18 L18 L18 L18 P5 P5 P5 P5 Q11 Q11 Q11 Q11 Q11 Q11 Q11 Q11 Y14 Y14 Y14 Y14 Y14 AC2 1’data combined over years and locations 60 Table A12. Markers siglificantly associated (P<0.05) with washed drained weight in three populations of navy beans. Combination of data used in muses Yearl Locerl Loc2le Year2 Locer2 Loc2Yr2 Cmb' Locl Loc2 Pop Signficant markers 2 A18 A18 F51 F51 F5b F5b F5b F5b 12 12 M10 M10 M10 M10 M10 M10 M10 M10 M10 O31 O31 O31 O31 03b 03b 03b 03b P5 P5 P5 P5 P5 P7 P16 Y4t Y4b Y4b Y4b Y4b Y4b Y4b Y4b Y4b Z4 Z4 Z4 Z4 AAl AAI M1 M1 M1 AAl AAI M1 M1 4 A14 818 818 C5 12 19b 19b M5 M5 N17 N181 N18t N181 N18b N18b 016 X17 X 17 Y3b Y3b ' Y5 Y5 Y5 Y5 5 F51 F51 F51 G4 G4 G4 P5 P5 P5 P5 P5 P5 P5 Q11 Q11 Q11 Q11 Q11 Q11 Q11 Y4b Y4b Y4b Y4b Y4b AC2 'data combined over years and locations 61 Table A13. Markers significantly associated (P<0.05) with hydration coeficient in three populations of navy beans. Combination of data used in analyses Yearl Locerl Loc2le Year2 Locer2 L002Y12 Cmb' Locl Loc2 Pop Significant markers 2 C5 C5 F51 F51 G4 H181 H18b H18b H18b H18b M10 N15 N17 N17 N17 N17 N17 031 03b Q3 Q3 Q3 Y4b Y4b AB6 AB6 AB6 AB6 AC8 AC8 AC8 AC8 A017 4 A14 A14 A14 A14 A14 A14 A14 A14 818 , B18 818 818 818 B18 818 818 C5 C5 C5 C5 C5 C5 H12t H121 1181 1181 1181 J91 J91 J91 J91 19b 19b MZ MZ MZ MZ MZ 112 M2 MZ M5 M5 M5 M5 M5 M5 M5 M10 M10 M10 M10 M10 N17 N17 N17 N17 N17 N17 N181 N18t N181 N181 N181 N18t N18m N18m N18m N18m N18m N18m 016 X3 X3 X3 X3 X3 X17 Y5 Y5 Y5 Y5 Y5 Y5 Y13 Y13 Y13 Y13 Y13 Y13 Y13 5 B15 B15 BIS BlS BIS B15 815 F9 F9 F9 J9 J9 L8 L8 L8 L8 L8 L8 M11 M11 M11 M11 N9 N9 N9 N9 N9 N9 N9 N9 016 016 016 016 016 016 P17 X3 X3 Y13 Y13 Y13 Y13 Y14 Y14 Y14 Y14 Y14 Y14 Y14 AA19 AC8 AC8 AC8 AC8 'data combined over years and locations 62 Table A 14. Markers significantly associated (P<0.05) with percent solids lost in three populations of navy beans. Combination of data used in analyses Yearl Locerl Loc2le Year2 Locer2 Loc2Yr2 Cmb' Locl Loc2 Pop Significant markers 2 F51 F51 F5b M10 M10 031 031 03b 03b 95 P5 95 p5 Q3 Q3 Y4t Y4b Y4b Y4b Y4b Y4b Z4- z4 Z4 Z4 M1 M1 AA! 4 A14 A14 818 318 cs C5 C5 C5 C5 C5 H121 H12t H121 H121 r1121 H121 H12b H181 M2 M2 M2 M2 M2 M2 M2 M2 M10 M10 M10 M10 N17 N17 N17 N17 N17 N18t N18t N18t N18t N18t P16 P16 P16 Q11 Q11 Q11 Q11 Q11 Q11 X3 X3 X7 Y3t Y5 Y5 Y5 Y5 Y5 Y13 AC2 5 L8 M11 M11 N18 N18 N18 N18 P5 as as Y13 Y13 Y14 AC2 AC2 AC2 AC2 Tdata combined over years and locations 63 Table A 15. Markers selected for multiple regession analysis. Population/Trait Markers selected Population 2 Visual score A18 Texture F51, G4, Y4b Hydration coeficient N17, AC8 Washed drained weight M10, 031, 03b, P5, Y4b, AAl Percent solids lost PSLY4b, Z4 Population 4 Visual score A14, BIB, 12, M11, N18b, Y3t Texture N18b, X7, Y3b Hydration coemcient A14, B18, C5, M2, M5, M10, N17, N18t, N18m, X3, Y5, Y13 Washed drained weight None Percent solids lost C5, H121, M2, M10, N17, N18t, Q11, Y5 Population 5 Visual score L8, M11, Q11, X3 Texture F51, G4, L18, Q11, Y14 Hydration coeficient B15, L8, M11, N9 016, Y14 Washed drained weight P5, Q11, Y4b Percent solids lost N18, AC2 Table 16. Chart showing marker genotypes and their relationship to canning quality traits in population 2. Avg. with band Avg. with band Trait” Marker absentt present' Visual score A18 3.38 3,20 Texture F51 _6§_4;_ 587 G4 589 6_6_4; Y4b 2:5 588 Hydration coefficient N17 __98 1.92 Washed drained weight M10 299 3 294.75 031 m 295.73 03b 295.73 23,59 P5 219,12 295.77 Y4b 294.44 299.53 AAl 300,25 295.42 Solids lost P5 10,; 11.1 Y4b 11.3 , g); Z4 11 1 10_.5 *undcrlining indicates the more desirable value for the trait ”visual score, 1-7; texture, Newtons/100g, hydration coefficient, ratio; washed drained weight, g; solids lost, %. 65 Table 17. Chart showing marker genotypes and their relationship to canning quality traits in population 4. Avg. with band Avg. with band Trait" Marker absent’ present' Visual score A14 2,52 3.11 818 2,32 3.09 12 2,22 3.06 M11 2,21 3.12 N18b M 3.06 Y3t 235; 2.58 Texture N18b 221 560 X7 566 612 Y3b 570 @ Hydration coeflicient A14 1.86 1.82 318 1.86 1,22 C5 1,82 1.86 M2 1.86 ;& M5 m 1.87 M10 1a 1.87 N17 LS2 1.86 N18t 1,22 1.85 N18m 1,22 1.87 X3 1 87 Lg Y5 1 85 2,22 Y13 l 87 w Solids lost C5 7.8 22 H121 7.8 32; M2 6._7 7.9 M10 8.0 1,; N17 7.8 22 N18t 7.8 fl Q11 12 7.9 Y5 ' 6,2 7.8 'underlining indicates the more desirable value for the trai—t flvisual score, 1-7; texture, Newtons/100g, hydration coefficient, ratio; washed drained weight, g, solids lost, %. 66 Table A 18. Chart showing marker genotypes and their relationships to canning quality traits in population 5. Avg. with band Avg. with band Trait" Marker absent‘ precent' Visual score LS 224; 2.57 M11 M 2.54 Q11 2.61 2,19 X3 2g 2.63 Texture F5 J_(_)_8_ 616 G4 616 M L18 640 73_8 Q11 628 Z4_8 Y14 l_4__5_ 642 Hydration coefficient BIS M 1.92 L8 2% 1.92 M11 _lh9_5_ 1.92 N9 1.92 1,26 016 1.93 _1_,2§ Y14 1:11 1 92 Washed drained weight P5 297,75 291.54 Q11 296,23 289 94 Y4 292.06 296,39 Solids lost N18 12.4 11,2 AC2 12.2 1 5 funderlining indicates the more desirable value for the trait "visual score, 1-7; texture, Newtons/100g; hydration coefficient, ratio; washed drained weight, g; solids lost, %. 67 Table A 19. Proposed linkage goups for population two. Distance between Total length of 1M e group Markers , markers’ W l F5t 3.8 CM 3.8 CM G4 2 F10 8.7 CM 8.7 CM 12 3 M10 6.1 CM 14.1 CM Z4 6.1 CM O3t 0.0 CM 03b 1.8 CM M1 4 A18 6.1 CM 12.3 cM Q11 6.1 cM L18 5 CS 6.1 CM 6.2 CM N17 0.00 CM AC8 0.00 cM AB6 'cM =- centimorgans 68 Table A20. Proposed linkage goups for population four. Distance between Total length of linkage _I_.ii1k_age_goup Marker markers’ group’ 1 N18m 4.2 cM 8.5 cM N181 0.0 CM CS 4.2 cM Y5 M2 7.7 CM 19.6 CM H12t 11.9 cM Q11 AC2 0.0 cM 14.4 CM H12b 14.4 CM M11 118 11.9 CM 27.3 CM A14 7.7 cM B18 7.7 cM X17 19b 14.4 cM 14.4 CM ' Y3 016 7.7 cM 17.3 cM M10 2.7 cM X3 2.7 cM Y13 4.2 cM M5 AAl 1.3 cM 1 .3 cM 031 0.0 cM 03b AA19 5.9 CM 20.3 CM Q3 14.4 CM N2 'cM = centimorgans 69 Table A21. Proposed linkage goups for population five. Distance between Total length of linkage _Li£k_age_goup Marker markers’ goup' 1 L8 6.4 CM 22.7 CM N9 4.0 CM BIS 4.0 CM Y13 1.9 CM X3 6.4 CM 016 2 G4 0.0 CM 0.0 CM F5t 3 L18 6.4 CM 6.4 CM Q1 1 4 M2 6.4 CM 6.4 CM ' AC2 5 Gl9t 4.0 CM 4.0 CM M19 6 AB6 6.4 CM 6.4 CM AC8 'cM '- centimorgans LIST OF REFERENCES Abbo, S., G. Ladizinsky and N. Weeden. 1992. Genetic analysis and linkage study of ‘ seed weight in lentil. Euphytica 58:259-266. Agbo, G., G. Hosfield, M. Uebersax, K. Klomparens. 1987. 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