Environmental effects on oil, fatty acid profile, protein and glucosinolate content in Indian mustard (Brassica juncea)

Abstract

Environmental influence over oil, fatty acid profile, protein, glucosinolates, oil stability index, monounsaturated fatty acids to polyunsaturated fatty acid, polyunsaturated fatty acid to saturated fatty acids and ω-6 to ω-3 fatty acid ratio was investigated by growing 25 Indian mustard (Brassica juncea L. Czern & coss) varieties during winter season (rabi) (October–April) 2003–06. The expression of all the parameters studied was significantly affected by genotypes, environment and genotype × environment interactions. Oil and protein content were relatively consistent over the seasons as indicated by low coefficients of variability (1.7–4.8%). Similarly, glucosinolates (CV 7.0–7.5%) and erucic acid (CV 4.0–8.0%) content were less affected by the cropping seasons. The oil stability index, ω-6 to ω-3 fatty acid and polyunsaturated fatty acid to saturated fatty acid ratio were more prone to environmental conditions than the fatty acids per se. Of all the nutritional and shelf-life indices of oil, monounsaturated fatty acid to polyunsaturated fatty acid ratio had the least variability across the years. The pattern of correlations was also affected by the prevailing environmental conditions during the cropping season. The relationship of maximum temperature up to 42 days after flowering and oil content was negative and significant. The negative correlation coefficients of erucic acid with mean temperature were significant only during (2004–05 and 2005–06) and 43–56 days after flowering in 2004–05 cropping season. In the 2005–06 cropping season, mean relative humidity during 15–28 days after flowering had negative and significant relationship with linoleic acid but significantly positive with linolenic acid.