HETEROSIS AND GENE ACTION FROM 7x7 DIALLEL ANALYSIS IN Brassica nap us L.

Abstract

An experiment on oleiferous Brassica napwi L. was conducted to evaluate the heterosis and gene action for ten different characters. Out 21 of F1 s, the hybridsBS-7xNAP179showed desirable negative heterosis for the characters of shorter plant height.No crosses showed desirable negative heterosis for early flowering and early maturity. There was also no crosses showed desirable positive heterosis for no. of primary branches per plant, no. of secondary branches per plant and siliqua length. The hybrids NAP94006xl3S-7. NAP-9908xNAP 179 and BS-1 3xN AP-248were found to exhibit the best heterosis for no. of siliquaeper plant. For thousand seed weight the hybrid NAP94006xNAP- 179 was best. For seed yield per plant the crosses NAP-94006xNAP- 179 was found to be the best. The parent NAP-248 was the best general combiner for early flowering and seed yield per plant, parent 135-7 for high no. of secondary branches and desirable plant height, parent BS-13for early maturity, no. of primary branches per particle and no. of seeds per siliqua while the parent NAP-I 79 was the best general combiner for 1000 seed weight. On the basis of average score and rank position, that cross NAP9908x NAP-94006 was good specific combiner for no. of secondary branches andno. of siliquae per plant. The combination NAP94006xNAP179was the best specific combiner for early flowering and seed yield per plantwhile NAP_94006xNAP-248was the best for early maturity. The hybrid NAP248x NAP-179was the best for no. of primary branches per plant. For siliqua length NAP_2037x BS-I3was the best specific combiner. The cross NAP94006xNAP248was the best for the no. of seeds per siliqua and BS-I3XNAP-179 was best for 1000-seed weight.