Screening for Osmotic Stress Responses in Rice Varieties under Drought Condition  

作　　者：Simon SWAPNA Korukkanvilakath Samban SHYLARAJ 

机构地区：[1]Rice Research Station, Department of Plant Breeding and Genetics, Kerala Agricultural University, Vyttila, Ernakulam 682019,Kerala, India

出　　处：《Rice science》2017年第5期253-263,共11页水稻科学（英文版）

基　　金：the financial support provided by the University Grant Commission(UGC),Government of India,in the frame of the UGC Postdoctoral fellowship programmer ‘Molecular characterization of drought tolerance in rice(Oryza sativa L.)’

摘　　要：Drought is the major abiotic stress factor that limits rice production worldwide.To evaluate the osmotic stress responses in rice varieties under drought condition,a total of 42 high-yielding rice varieties were collected from various research stations of Kerala Agricultural University in India.The experimental setup comprises of initial hydroponic treatments at different osmotic potentials,artificially induced by desired strengths of polyethylene glycol(PEG6000),and followed by the pot planted experiments in the rain-out-zone.The activities of antioxidant enzymes,relative water content,cell membrane stability,photosynthetic pigments,proline content,along with plant growth parameters of the varieties under drought condition were evaluated.Moreover,the standard scores of these rice varieties were assessed under stress and recovery conditions based on the scoring scale of the Standard Evaluation System for rice.Among the 42 rice varieties,we identified 2 rice varieties,Swarnaprabha and Kattamodan,with less leaf rolling,better drought recovery ability as well as relative water content,increased membrane stability index,osmolyte accumulation,and antioxidant enzyme activities pointed towards their degree of tolerance to drought stress.The positive adaptive responses of these rice varieties towards drought stress can be used in the genetic improvement of rice drought resistance breeding program.Drought is the major abiotic stress factor that limits rice production worldwide.To evaluate the osmotic stress responses in rice varieties under drought condition,a total of 42 high-yielding rice varieties were collected from various research stations of Kerala Agricultural University in India.The experimental setup comprises of initial hydroponic treatments at different osmotic potentials,artificially induced by desired strengths of polyethylene glycol(PEG6000),and followed by the pot planted experiments in the rain-out-zone.The activities of antioxidant enzymes,relative water content,cell membrane stability,photosynthetic pigments,proline content,along with plant growth parameters of the varieties under drought condition were evaluated.Moreover,the standard scores of these rice varieties were assessed under stress and recovery conditions based on the scoring scale of the Standard Evaluation System for rice.Among the 42 rice varieties,we identified 2 rice varieties,Swarnaprabha and Kattamodan,with less leaf rolling,better drought recovery ability as well as relative water content,increased membrane stability index,osmolyte accumulation,and antioxidant enzyme activities pointed towards their degree of tolerance to drought stress.The positive adaptive responses of these rice varieties towards drought stress can be used in the genetic improvement of rice drought resistance breeding program.

关 键 词：DROUGHT resistance RICE ANTIOXIDANT ENZYME OSMOLYTE relative water content 

分 类 号：S511[农业科学—作物学]