Inheritance of erucic and oleic acid content and correlation among fatty acids in Indian mustard [B. juncea (L) Czen and Coss.]

Rapeseed-mustard oil is used as edible oil, as well as raw material for industrial products like soap, cosmetics, lubricants, paints, plasticizers, etc. In the present study six generations viz. P1, P2, F1, F2, BC1 and BC2 of three crosses, viz. PRQ-9701 x Kranti, JLM-23 x Kranti and PLEM-2003-9 x Varuna were grown in a RBD. The non-significant difference between F1 and their reciprocal F1 for erucic and oleic acid contents indicated absence of maternal influence. Estimation of effective factor pairs indicated that parents utilized in these crosses differed by at least two genes for both the fatty acids. For erucic acid content the observed ratio in F2 population (18:85:152:87:25) was not significantly different from the expected ratio (1:4:6:4:1), similarly for oleic acid the observed F2 ratio (23:86:150:84:25) was also not significantly different from the expected ratio which indicated digenic inheritance of these fatty acids. The simple additive-dominance model was adequate in the two crosses for erucic acid and in all the three crosses for oleic acid content, suggesting the absence of non-allelic interactions. In one cross additive x additive interaction was found significant for erucic acid but the additive effect had the highest magnitude. Therefore, the additive gene effects could be exploited by the pedigree method of breeding for selecting low erucic and high oleic acid content segregants in the F2 generation. Correlation studies among the major fatty acids revealed that erucic acid exhibited negative and significant correlation with palmitic, stearic, oleic, linoleic and linolenic acids. The linoleic and linolenic acids had a positive and significant association with each other as well as with oleic acid. Correlation studies revealed that the lines with 2% erucic acid coupled with approximately 40-45% oleic, 30-35% linoleic, 15-20% linolenic and 5% saturated fatty acids could be developed.