Submitted to: Journal of Nematology
Publication Type: Abstract Only
Publication Acceptance Date: 7/11/2005
Publication Date: 9/1/2005
Citation: Cetintas, R., Dickson, D.W., Brito, J.A., Nyczepir, A.P. 2005. Pathogenicity of Meloidogyne mayaguensis compared with M. incognita, M. arenaria, M. javanica and M. floridensis on tomato in microplots in Florida. Journal of Nematology [abstract]. 37:361. Interpretive Summary: Tomato is an important vegetable crop in Florida. The root-knot nematode is an important pathogen on tomato if proper management practices are not followed. Meloidogyne mayaguensis is a highly virulent root-knot nematode recently reported infecting different horticultural and ornamental plants in Florida. However, its pathogenicity status on tomato is unknown relative to other common root-knot nematode species. Determining the pathogenicity of M. mayaguensis relative to other root-knot species in Florida needs to be investigated. Microplots were infested with two levels of each of the Peanut, Southern, Javanese, Peach, and A Root-Knot Nematode planted to Solar-Set tomato. Eighty-two days after inoculation, results indicate that tomato infested with A Root-Knot Nematode (i.e., M. mayaguensis) had a greater percentage of galls and eggs than most of the other species evaluated. The size of the galls produced by this nematode was also much larger. These data provide useful insights into the pathogenicity of M. mayaguensis on tomato which will be very important in the development of appropriate nematode management strategies.
Technical Abstract: Meloidogyne mayaguensis is a highly virulent root-knot nematode recently reported infecting various horticultural and ornamental plants in Florida. It is been reported that M. mayaguensis is able to break root-knot nematode resistance genes on tomato, sweet potato, and soybean and also induce more severe disease on many economically important crops compared to other common root-knot nematodes. Our objective was to determine the pathogenicity of this nematode relative to other common species found in Florida, namely M. arenaria, M. incognita and M. javanica. Microplots were inoculated with two levels of each nematode (low = one second-stage juvenile (J2) or egg/g of soil, high = three J2 or eggs/g of soil). 'Solar set' tomato was grown in the microplots for 82 days. The plants were removed and nematode densities in soil, percentages of roots galled, eggs, and plant fresh weights and heights were recorded. M. mayaguensis had a greater number of eggs than all other Meloidogyne spp. with the exception of M. arenaria (P  O.OS). M. mayaguensis also had a greater percentage of root galling at both inoculum levels, 95% and 99% for low and high, respectively. The size of galls induced by M. mayaguensis was unusually large compared with the other three species. M. arenaria had a greater number of J2 in soil than all other Meloidogyne spp. Fresh weight and height of plants were not different among treatments.