Inheritance of low erucic acid content in Indian Mustard Brassica juncea L Czern and Coss

Abstract

newline Indian mustard (Brassica juncea) is an important crop of this region and it occupies 80 % area of the rapeseed-mustard group of crops. The oil obtained from these varieties grown in India are usually characterized by high erucic acid. Significant variation in erucic acid occur within the seed oils of Brassica juncea. Therefore, two varieties having high erucic acid (RSPR-03 and RH-749) and two varieties with low erucic acid (PM-21 and Pusa Karishma) were used to derive F1s, BC1F1 and BC1F2 generations to determine genetic variation for erucic acid and its modes of inheritance in the present study. Selfed generation seeds along with F1, BC1F1 and parents were phenotyped using gas liquid chromatography (GLC) for erucic acid content. A total of 10 plants from each parents, 20 plant from F1s, 98-108 plants from BC1F1 and 204-206 plants from BC1F2 were phenotyped. The erucic acid content ranged from 17.12 to 41.94 %. Erucic acid content is found to be less in BC1F2 generation of the backcrosses as compared to parents. Lowest value of erucic acid was found in the oil of BC1F2 generation of backcross [RSPR-03 × (RSPR-03 × Pusa Karishma)] i.e. 17.12% followed by BC1F2 generation of the backcross [RH-749 × (RH-749 × PM-21)] i.e. 18.48%. The population statistically fit well in the segregating ratio of 1:4:6:4:1 indicated the digenic inheritance of erucic acid with additive gene effect, low erucic acid being recessive in nature. BC1F2 of [RSPR-03 × (RSPR-03 × Pusa Karishma)] has shown maximum value for more than 50% of morphological as well as biochemical traits. The above results were evaluated via. genetic as well as molecular data concluding that [RSPR-03 × (RSPR-03 ×Pusa Karishma)] was showing 6 bands with high erucic acid content and 4 bands with low erucic acid content ranging from 35.4-40.0 % and 1.0-1.7 % respectively. The two selfed generations of [RSPR-03 × (RSPR-03 × Pusa Karishma)] and [RH-749 × (RH-749 × PM-21)] can be used for developing genotypes of the low-erucic acid which wil