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.

Keywords:

• Breeding
• resistance
• sensitivity
• susceptibility
• tolerance
• yield loss

Acknowledgements

The authors would like to thank the International Rice Research Institute (IRRI) for the seeds, equipment, facilities and to Luzviminda Fernandez, Sergio Velasco and Juan Reyes for their technical assistance.