Genetic analysis for chilli veinal mottle virus resistance in chilli (Capsicum annuum L.)

Abstract

Though India is the largest producer of chilli in the world covering an area of 8.922 lakh ha, its production (9.213 lakh t) and productivity (1030 kg/ha dry yield) are considerably low. Among the factors that limit its production, viruses play an important role. Around 21 viruses are reported to be affecting chilli in India, of which chilli veinal mottle virus (ChiVMV) and cucumber mosaic virus (CMV) transmitted mechanically and aphids in non-persistent manner are very important. In India cultivars with good amount of potyvirus resistance coupled with high yielding potential are lacking in chilli. A few varieties viz., Pant C-1, Tiwari, Punjab Lal are developed for virus resistance, their acceptability in the country is limited. Therefore, a few experiments were conducted to confirm resistance to ChiVMV in the improved lines at IIHR, to study genetics of resistance to ChiVMV resistance; and to study heterosis, combining ability and gene action of the hybrids developed using promising ChiVMV resistant lines. Segregation patterns for disease reaction in F1, F2 and backcross generations along with their corresponding parents suggested monogenic recessive condition for ChiVMV resistance. Heterosis study indicated the superiority of some out standing hybrids over better parent. Combining ability studies indicated that both gca and sca effects were important for all the characters studied, however the gca variance was lesser than the sca variance expressing the non-additivity preponderance. Parents with high mean performance and significantly desired effects along with F1s having significantly desired sca effects have been pooled. The gene action study illustrated that the characters viz., number of secondary branches per primary branch, average fruit weight, stalk length, fruit width and ChiVMV resistance were under control of both additive and non-additive effects. Epistasis was operating in few traits viz., early flowering, plant height, plant spread, fruit width and seed ratio per fruit. Fruit length was under the control of additive gene action.