Resistance to Rotylenchulus reniformis, Heterodera cajani, and Meloidogyne javanica in Accessions of Cajanus platycarpus . S. B. Sharma, Scientist (Nematology), International Crops Research Institute for the Semi-Arid Tropics, ICRISAT Asia Center, Patancheru, Andhra Pradesh 502 324, India. Plant Dis. 79:1033-1035. Accepted for publication 20 April 1995. Copyright 1995 The American Phytopathological Society. DOI: 10.1094/PD-79-1033.

Rotylenchulus reniformis, Heterodera cajani, and Meloidogyne javanica are important nematode pathogens of pigeonpea (Cajanus cajan), a legume crop cultivated widely in the semiarid tropics. Accessions of Cajanus platycarpus, a wild relative of pigeonpea, were evaluated in the greenhouse for resistance to R. reniformis race A, H. cajani, and M. javanica races 1 and 3. Two accessions, ICPWs 60 and 62, were resistant to R. reniformis race A. ICPWs 62, 69, and 70 were resistant to H. cajani. All the accessions were susceptible to M. javanica races. Race 1 produced bigger galls than those produced by race 3. ICPW 64 had lower damage indices (7.7 for race 1, and 5.4 for race 3) than other accessions. ICPW 62 was the only accession with resistance to two nematode species, H. cajani and R. reniformis. Seed of ICPWs 62, 69, and 70 with high levels of resistance to H. cajani were collected and multiplied. These lines will be useful in breeding programs as well as in research to obtain an understanding of the mechanism of resistance.

Keyword(s): multiple resistance