|Author:||Muhammad, Farooq ; Abdul, Wahid ; Lee, DongJin|
|Book Group Author:||NA|
Drought stress hampers rice performance principally by disrupting the plant-water relations and structure of biological membranes. This study appraised the role of polyamines (PAs) in improving drought tolerance in fine grain aromatic rice (Oryza sativa L.). Three PAs [putrescine (Put), spermidine (Spd) and spermine (Spm)] were used each at 10 µM as seed priming (by soaking seeds in solution) and foliar spray. Primed and non-primed seeds were sown in plastic pots with normal irrigation in a phytotron. At four-leaf stage, plants were subjected to drought stress by bringing the soil moisture down to 50% of field capacity by halting water supply. For foliar application, 10 µM solutions each of Put, Spd and Spm were sprayed at five-leaf stage. Results revealed that drought stress severely reduced the rice fresh and dry weights, while PAs application improved net photosynthesis, water use efficiency, leaf water status, production of free proline, anthocyanins and soluble phenolics and improved membrane properties. PAs improved drought tolerance in terms of dry matter yield and net photosynthesis was associated with the maintenance of leaf water status and improved water use efficiency. Among the antioxidants, catalase activity was negatively related to H2O2 and membrane permeability, which indicated alleviation of oxidative damage on cellular membranes by PAs application. Foliar application was more effective than the seed priming, and among the PAs, Spm was the most effective in improving drought tolerance.
|Pages:||937 - 945|
|Journal:||Acta Physiologiae Plantarum|
anthocyanins, catalase, drought resistance, enzyme activity,enzymes, irrigation, leaf water potential, photosynthesis, plant waterrelations, polyamines, proline, putrescine, rice, seeds, soil water,spermidine, Oryza, Oryza sativa, Oryza, Poaceae, Cyperales,monocotyledons, angiosperms, Spermatophyta, plants, eukaryotes, carbonassimilation, carbon dioxide fixation, drought tolerance, paddy, soilmoisture, watering, Field Crops (FF005) (New March 2000), PlantPhysiology and Biochemistry (FF060), Plant Water Relations (FF062),Plant Production (FF100), Environmental Tolerance of Plants (FF900),Soil Water Management (Irrigation and Drainage) (JJ800) (Revised June2002) [formerly Soil Water Management]