Reproduction of Meloidogyne javanica in soybean genotypes

Area of Science:

• Plant Pathology
• Nematology
• Agronomy

Background:

• Meloidogyne javanica is a significant pest of soybean crops, causing substantial damage.
• Genetic resistance is the preferred method for controlling this nematode, but resistant soybean cultivars are scarce in Brazil.
• Limited availability of resistant cultivars necessitates evaluating existing soybean varieties for their reaction to M. javanica.

Purpose of the Study:

• To assess the susceptibility of widely cultivated soybean cultivars to Meloidogyne javanica.
• To identify soybean genotypes with reduced reproduction of M. javanica for potential use in Brazil.

Main Methods:

• Thirty-seven soybean cultivars were inoculated with a standardized suspension of 5,000 Meloidogyne javanica eggs and second-stage juveniles.
• Nematode reproduction factor (RF), root galling, and nematode population density were evaluated 60 days post-inoculation.
• Data were analyzed using analysis of variance and the Scott-Knott cluster test at a 5% probability level.

Main Results:

• All tested soybean genotypes supported reproduction of Meloidogyne javanica, with reproduction factors (RF) greater than 1.00.
• Significant variations in susceptibility levels were observed among the cultivars.
• The lowest nematode reproduction was recorded in cultivars M 5947 IPRO, HO AMAMBAY IPRO, BMX GARRA IPRO, and FPS ATALANTA.

Conclusions:

• No soybean cultivar tested was completely immune to Meloidogyne javanica.
• Cultivars M 5947 IPRO, HO AMAMBAY IPRO, BMX GARRA IPRO, and FPS ATALANTA demonstrate potential for integrated management strategies due to lower nematode reproduction.
• Further research into these less susceptible cultivars could contribute to developing more effective control measures for soybean root-knot nematode.