IDENTIFICATION OF RESISTANT SOURCES TO COWPEA WEEVIL (CALLOSOBRUCHUS-MACULATUS (F)) IN VIGNA SP AND INHERITANCE OF THEIR RESISTANCE IN BLACK GRAM (VIGNA-MUNGO VAR MUNGO)
Tk. Dongre et al., IDENTIFICATION OF RESISTANT SOURCES TO COWPEA WEEVIL (CALLOSOBRUCHUS-MACULATUS (F)) IN VIGNA SP AND INHERITANCE OF THEIR RESISTANCE IN BLACK GRAM (VIGNA-MUNGO VAR MUNGO), Journal of Stored Products Research, 32(3), 1996, pp. 201-204
Seventy-five cultivated accessions and two wild progenitors of black g
ram and mungbean were evaluated for their resistance to infestation by
Callosobruchus maculatus. None of the cultivated accessions either of
black gram or mungbean was found to be resistant. However, resistance
was evident in a wild progenitor of black gram Vigna mungo var. silve
stris. The mechanism of resistance of V. mungo var. silvestris was exa
mined and it was found to be larval antibiosis expressed as reduced su
rvival, longer developmental period and reduced body weight. V. mungo
var. silvestris was successfully crossed with black gram accession TAU
-1. In F-1 plants, pollen fertility was normal and seeds were complete
ly resistant to C. maculatus. Inheritance of bruchid resistance was fu
rther studied in F-2 and F-3 generations. In the F-2 generation, a 15:
1 ratio was observed indicating the presence of two dominant duplicate
genes that are controlling resistance to C. maculatus. The segregatio
n of F-3 plants was as expected for a digenic ratio and segregation sh
owed a good fit to a 7:4:4 ratio (chi(2) = 0.28). These resistant gene
s have been designated as Cmr(1) and Cmr(2). Copyright (C) 1996 Publis
hed by Elsevier Science Ltd.