ARS | Publication request: REPRODUCTION OF MELOIDOGYNE MAYAGUENSIS FROM FLORIDA ON ROOT-KNOW NEMATODE RESISTANT TOMATO AND PEPPER

Submitted to: Journal of Nematology
Publication Type: Abstract Only
Publication Acceptance Date: December 20, 2005
Publication Date: N/A

Technical Abstract: Meloidogyne mayaguensis is a highly virulent pathogen of many crops including tomato and pepper. Isolates of this pathogen collected in other countries have been reported to reproduce on tomato genotypes which are resistant to the major root-knot nematode species. Studies were conducted to determine the reproduction of an isolate of M. mayaguensis from Florida on root-knot nematode resistant tomato (resistance conferred by Mi-1 gene) and resistant pepper (resistance conferred by the N gene and additional genes). M. incognita race 4 was used as a control. Four resistant tomato genotypes ‘BHN 543’, ‘BHN 585’, ‘BHN 586’, and ‘Sanibel’ were compared with the susceptible ‘Rutgers’ tomato; and four resistant pepper genotypes ‘Charleston Belle’, 9913/2, 97.9001, and 97.9008 were compared with the susceptible ‘Keystone Resistant Giant’ pepper. Tomato was tested at 22 and 33 C in growth chambers, and at 26 ' 1.8 C in a growth room. Meloidogyne mayaguensis reproduced on all Mi-1 gene tomato at all temperatures, whereas M. incognita reproduced only at 33 C. Pepper, which was tested at 24 C, was infected only by M. mayaguensis. Galling and egg mass indices, and the reproduction factor for M. mayaguensis were significantly different than those for M. incognita race 4 in all resistant tomato and pepper genotypes. Meloidogyne mayaguensis from Florida overcame the Mi-1 resistance gene in tomato genotypes, and N resistance gene in ‘Charleston Belle’ pepper, and other gene(s) that confer resistance to root-knot nematodes in pepper lines 9913/2, 97.9001, 97.9008.