Solanum lycopersicum L (tomato) is native to South and Central America. It is grown world-wide on about ten million acres, yielding circa 185 million tons of fruit on an annual basis. To make this crop available on a year-round basis, greenhouse tomatoes are commonly grown in countries such as the Netherlands, Canada and Uzbekistan. Tomato is the second staple vegetable in Central Asia after potato. About four million tons were produced in Central Asia in 2013. Tomatoes are eaten raw or cooked and are rich in essential vitamins and minerals. Their color comes from lycopene, which is responsible for the antioxidants reported to alleviate risk to human health issues such as heart disease, hypertension, congestive heart failure, prostate cancer and atherosclerosis.Tomato can be susceptible to numerous insect pests and infectious disease pathogens. Tomato hornworm (Manduca quinquemaculata), cotton bollworm (Helicoverpa armigera), corn earworm (Helicoverpa zea), potato aphid (Macrosiphum euphorbiae), green peach aphid (Myzus persicae), silver leaf whitefly (Bemisia tabaci), and greenhouse whitefly (Trialeurodes vaporariorum Westwood) are key insect pests of tomato. Whitefly is important because of its ability to cause direct feeding damage and vector viruses such as tomato yellow leaf curl virus (TYLCV) of the begomovirus genus.Numerous tomato cultivars have been developed for desirable, pest, horticultural and food attributes. Some have been adopted for their pest or pathogen resistance characteristics. For example, Anahu is a determinant tomato cv that has the Mi gene which confers resistance to southern root knot nematode (Meloidogyne incognita (Kofoid & White) Chitwood), and cross-resistance to potato aphid (Macrosiphum euphorbiae (Thomas)) and sweet potato whitefly (Bemisia tabaci (Gennadius)). Not all resistant tomato varieties, however, are suitable for tomato production, or preferred by farmers and consumers. Grafting has the potential to bring all the essential traits together.Grafting is a practice used in vegetable production systems to decrease risk to soil-borne diseases, increase salt tolerance, increase tolerance to other abiotic factors, increase drought tolerance, increase plant vigor, and increase yield. The research presented herein was aimed at determining if the grafted susceptible tomato cv Rutgers on top of resistant tomato cv Anahu will control two important tomato pests. Moreover, we measured plant biomass (fruit, stem and leaf, and root) of these two tomato cultivara with and without grafting in order to evaluate grafting impact on plant biomass allocation. Also, we counted the Type-D trichome density as these structures are thought to be responsible for pest resistance by acting as mechanical and chemical barriers.The results show that Anahu is not a good tomato cultivar to control M. incognita and T. vaporariorum. Anahu was not completely resistant to M. incognita. Moreover, on Anahu, significant decrease in T. vaporariorum population density occurred only when the M. incognita was present. Type-D trichome density was not responsible for a reduction of T. vaporariorum population density on Anahu. Thus, in order to draw a strong conclusion about Mi gene resistant to T. vaporariorum and resistance translocation from the rootstock to scion in grafted plants, there is a need for more advanced research, including molecular studies.
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