Host response of rice genotypes from crosses of high-yielding and drought-tolerant Oryza sativa advanced breeding lines to the rice root-knot nematode Meloidogyne graminicola

Abstract

The host response to Meloidogyne graminicola infection of 30 advanced breeding lines developed from crosses between high-yielding and drought-tolerant Oryza sativa genotypes was evaluated in outdoor raised beds. None of the advanced breeding lines showed resistance to M. graminicola comparable to the M. graminicola-resistant African rice (O. glaberrima) genotype TOG5674. However, rice genotype IR86815-23-4-1-2 was identified tolerant which showed no yield reduction even when infected with M. graminicola. IR82635-B-B-143-1, IR85733-19-4-1-1, IR85733-19-4-2-4, IR85,735-42-1-4-1 and IR 85735-42-1-4-4 were less sensitive to M. graminicola infection with less than 20% yield reduction compared to other rice genotypes. These rice genotypes could alleviate yield losses in M. graminicola-infested rice fields in regions with limited resources to control M. graminicola and when resistant cultivars are not available