COMBINING ABILITY AND HETEROSIS FOR SEED YIELD TRAITS INVOLVING NATURAL AND SYNTHETIC INDIAN MUSTARD (BRASSICA /UNCEA L. CZERN. and COSS.)

Abstract

Eleven diverse lines of B. juncea viz., Kranti, PR 8905, DIRA 337, TM 4, RML 198, RIL 8901, RJ 8901, CSR 83-268, RCC 15, NOR 8602 and RCC 4 used as females were crossed with three testers (RLM 619, P17 and Vardan as males) in a line x tester mating design to identify potential parents and cross combinations on the basis of heterosis and specific combining ability effects. Out of these testers, P17 is a newly reconstructed stable line developed by crossing B. campestris var. Candle with a land race of B. nigra. The resulting 33 hybrids along with the parents were grown at the Oilseeds Research Station, Kangra, Himachal Pradesh Krishi Vishvavidyalaya, in a randomized block design with two replications. Observations on five competitive plants from each plot were recorded for six quantitative traits (Table 1). Heterosis was estimated as percent increase or decrease over the better parent. The estimates of combining ability effects were estimated according to the method outlined by Kempthorne [1].