​Deciphering the Information on Inheritance Mode of Erucic Acid Trait in Indian Mustard (Brassica juncea L.)

Abstract

Background: Indian mustard [Brassica juncea (L.) Czern and Coss] is most important oilseed crop grown in Rabi season and have been used as a source of edible oil in the Indian subcontinent. Low use of mustard oil is basically due to the presence of high content of erucic acid which not only deteriorate the quality of oil but also have harmful effects on human body. Methods: Knowledge of erucic acid trait inheritance is crucial so as to define the breeding strategies for erucic acid trait in Indian mustard. In present study the experiment to study mode of inheritance of erucic acid trait was carried out among progeny of crosses involving high erucic acid (NRCHB-101) and low erucic acid (Heera and PDZ-1) cultivars of Brassica juncea. The study was conducted using six generations viz., P1, P2, F1, F2, B1 and B2 derived from the crosses, NRCHB-101 × Heera and NRCHB-101 × PDZ-1. Result: The content of erucic acid of F1’s was found intermediate between the parents while in F2 seeds itwas segregated into 5 classes i.e., less than 2%, 2-10%, 11-20%, 21-30% and greater than 30% with a genotypic ratio of 1:4:6:4:1. Backcross seeds (B1 and B2) derived from the F1 backcrossing with high erucic acid and low erucic acid parents were classified into three classes with a ratio of 1:2:1. The segregation patterns confirmed that in case of B. juncea two genes are responsible for governance of erucic acid trait and these genes are inherited in additive manner. The results of this investigation also showed that inheritance of erucic acid content trait is under embryonic control with absence of maternal effect in B. juncea. This understanding of B. juncea’s erucic acid inheritance will help breeders create B. juncea cultivars with zero erucic acid.