Host Plant Resistance for Bruchids in Pre-breeding Lines of Greengram [Vigna radiata (L.) Wilczek.

Background: Bruchid beetle (Callosobruchus chinensis) is one of the devastating field carry over storage pest causing a huge crop loss, especially in greengram. The pre-breeding lines were developed by crossing between a cultivated variety, VBN (Gg) 2 and Vigna radiata var. sublobata, a progenitor species of greengram used as a resistant parent against bruchid. Methods: A total of 53 stabilized inter sub-specific lines along with parents were screened for bruchid resistance by ‘no choice’ method with two replications. Screening parameters were recorded for all the 53 lines and were statistically analysed. Damage assessment was carried out and the three resistant lines obtained during initial screening was further confirmed. Result: The low seed damage per cent was observed in three lines viz., GGISC-2 (18.00), GGISC-21 (20.00) and GGISC-49 (14.00). The susceptibility index was 0.048, 0.049 and 0.048 in GGISC-2, GGISC-21 and GGISC-49, respectively and hence, classified as bruchid resistant. Delayed adult emergence, uneven adult emergence, prolonged developmental period, small and malformed adults were the other parameters observed in resistant lines. The three resistant lines identified could be further utilized in the breeding programmes for the development of bruchid resistant varieties in greengram. [ABSTRACT FROM AUTHOR]