Influence of Exogenously Applied Trehalose on Morphological and Physiological Traits of Flax (Linum usitatissimum) Plant Under Water Shortage Conditions

Water scarcity is the biggest issue which interrupts the physiological, morphological and biochemical process of the plants. Different osmolytes (trehalose, proline, glycine betaine etc) are applied to plants through rooting medium, pre-sowing method and foliar application which are helpful to detoxify the negative effects of drought stress and enhance the yield. Trehalose, an osmolyte which decreases the effects of water deficit conditions by protecting the structure of protein and lipid and function of enzymes. An experiment was performed to study the significant effect of trehalose on flax (Linum usitatissimum L.) under water deficit situation. Two levels of drought (normal watering and 50% FC (field capacity)) and four levels of trehalose (nonsoaked, water soaked, 10 and 20 mM) were used. Total 64 pots were used in which 50% drought was applied on 32 pots (in which 16 pots (in which four levels of trehalose were applied with 4 replicates of each treatment) as drought of Roshini and 16 pots as drought of Chandini) while other 32 pots (16 pots as control of Roshini and 16 pots as control of Chandini) used as control treatment. Consequences showed that water deficit conditions (50% FC) reduced the growth attributes, yield parameters, carotenoids content, POD (peroxidase) activity, nutrient use efficiency and uptake in both shoot and root while improved the total phenolics, MDA (malondialdehyde), H2O2 (hydrogen peroxide) and total free proline as compared to control conditions. Foliarly applied trehalose enhanced the shoot fresh weight, MDA, TSP (total soluble protein) and GB (glycine betaine), shoot length, leaf ascorbic acid and H2O2 in both flax varieties and reduced the alb ratio and MDA in Roshini. Trehalose increased the carotenoids contents in Chandini, POD, GB, total free proline, number of seeds/plant and number of capsules/plant in Roshini, and SOD (superoxide dismutase), CAT (catalase) activities in both flax varieties under 50% FC as compared to control conditions. Overall, performance of Chandini was better when 10 mM trehalose application was applied. Drought tolerance of several cereal and medicinal crops elevated by using different osmoprotectants, antioxidants and plant growth regulators. Trehalose application applied to ameliorate the effects of water stress and recovers the flax seed production, but limited information is available in literature on the role of trehalose on flax. How trehalose regulates the biochemical and physiological processes under both control and stress conditions?