Comparative Reproductive Potential of Meloidogyne enterolobii , M. floridensis , and M. incognita on Major Vegetable Crops in Georgia, USA

Vegetable production in Georgia faces significant challenges from different diseases and pests and one of them is root-knot nematodes (Meloidogyne spp.). In a recent statewide survey in major vegetable-growing regions in Georgia, two Meloidogyne species, guava root-knot nematode (M. enterolobii) and peach root-knot nematode (M. floridensis), were detected for the first time in addition to the commonly occurring southern root-knot nematode, M. incognita. Despite their emerging significance, comparative data on the reproductive capabilities of these recently detected species on key vegetable crops are lacking. This study evaluated the reproduction potential of M. enterolobii, M. floridensis, and M. incognita on eight economically important vegetable crops in Georgia: beet, broccoli, cabbage, cantaloupe, pepper, snap bean, squash, and tomato. Reproduction factor (final population/initial inoculum), galling index, and number of eggs per gram of root were quantified for each species in each vegetable crop. All Meloidogyne species reproduced in the tested vegetable crops in this study. In most experiments, M. enterolobii exhibited significantly higher Rf, galling indices, and egg counts per gram of root compared to M. incognita and M. floridensis across the majority of tested vegetable crops, with the exception of squash and tomato. On these two crops, all three species showed comparable values for the measured parameters. These findings highlight the high reproductive capacity and pathogenic potential of M. enterolobii on a broad range of vegetable hosts. Based on these findings, we hypothesize that in mixed-species populations within infested vegetable fields, M. enterolobii may become the predominant species due to its superior reproductive performance.