Biochemical parameters affected by abiotic stresses in Brassica juncea (L.)

An experiment was conducted to assess the impact of induced water logging (WL), high temperature (HT) as well as water logging + high temperature (WL+HT) on different biochemical parameters at various stages viz., 40 days after sowing (DAS), 80 DAS and 40 + 80 DAS in Indian mustard. Irrespective of the stage of exposure to different abiotic stresses, significant reduction in chlorophyll ‘a’, 39.71 and 36.76% respectively in WL and WL+HT chlorophyll ‘b’ 38.88% and total chlorophyll content 39.98% in WL was observed in comparison to control plants, while carotenoid content increased 40.60% in WL stressed plants. The deleterious effect was pronounced under water logged conditions followed by water logging + high temperature and high temperature. A pronounced increase in total soluble carbohydrates 47.18%, free amino acids 67.44% as well as proline content 438.88% was noticed in plants grown under water logging condition in respect to control plants, while starch content 54.73% decreased in water logging in response to control. Exposure at different stages had no significant differences in total soluble carbohydrates or starch content, while increase in free amino acids was the maximum 100.16% at 40 + 80 DAS, whereas proline content 511.45% at 40 + 80 DAS.