COINFECTION OF WILT-RESISTANT CHICKPEAS BY FUSARIUM-OXYSPORUM F-SP CICERI AND MELOIDOGYNE-JAVANICA

Fusarium oxysporum f.sp. ciceri and Meloidogyne javanica are important pathogens of chickpea. Interrelationships between F. oxysporum f.sp. ciceri and M. javanica were investigated on 53 Fusarium wilt-resistant chickpea genotypes in pot experiments. All of the genotypes were susc eptible to M. javanica. Fusarium wilt resistance in one genotype (ICC 12275) was ineffective in the presence of M. javanica, and all the pla nts completely wilted. Resistance in four genotypes (ICCs 11319, 11322 , 12254, 12272) was reduced in the presence of the nematode. Vascular discoloration above the collar region of the plants, an indication of susceptibility to the fungus, was observed. Wilt resistance in 48 geno types was not modified by M. javanica. The effects of interactions bet ween the pathogens on shoot and root weights, gall index, and galled a rea of root were significant only on 10-28% of the genotypes. Presence of the fungus reduced the adverse effects of nematodes on growth of 1 5% of the genotypes. Appraisal of wilt-resistant chickpea genotypes fo r their reactions to combinations of the two pathogens would help to i dentify and develop chickpea cultivars with wilt resistance stable in presence of M. javanica.