GENETIC DIVERSITY OF FIELD MUSTARD (BRASSICA RAPA L.) AND THEIR SATURATED AND UNSATURATED FATTY ACIDS ASSOCIATION

Abstract

The oilseed crop improvement for Brassica rapa L. (field mustard) is considered to be important in respect of yield production coupled with unsaturated fatty acids of the existing cultivars. Hence, the genetic diversity, and nutritional components of 14 B. rapa cultivars were evaluated based on their yield attributes and fatty acid profiles at the Sher-e-Bangla Agricultural University, Dhaka, Bangladesh. These 14 B. rapa cultivars differed significantly and were grouped into five diversified clusters. The highest intra-cluster distance was found in cluster II (2.43), while the highest inter-cluster distance was found between clusters II and V (20.41). In the fatty acid profile, the maximum threshold acceptable level (<7%) of saturated fatty acids for human consumption was found in Sonali Sarisha and BARI Sarisha-14. The total monounsaturated fatty acids viz., oleic, eicosenoic, and erucic acid ranged from 62.74% in BARI Sarisha-15 to 69.51% in Sonali Sarisha. The highest oleic acid and eicosenoic acid were obtained from the local variety, Maghi (21.06%) and Improved Tori (9.08%). The highest essential linoleic and linolenic acids were found in BARI Sarisha-15 (17.10%) and Improved Tori (8.16%), respectively. However, the local cultivar Maghi, containing the highest oleic acid (21.06%) has the lowest erucic acid (35.53%). On the other hand, BARI Sarisha-14 contained the lowest oleic (17.22%) and the highest erucic (44.02%) acids. The negative and strong correlation also reinforced the reverse relationship between oleic and erucic acids. Similarly, both linoleic (-0.497) and linolenic (-0.443) acids also showed a negative correlation with erucic acid. As a whole, BARI Sarisha-14, BARI Sarisha-15, Maghi, Sonali Sarisha, and Improved Tori could be selected as potential parents for a hybridization program to breed potential recombinant lines with higher oil content and healthier unsaturated oleic and linoleic fatty acids.