Comparative Effects of GA₃,Kinetin,and Salicylic Acid on Emergence,Seedling Growth,and Antioxidant Defense System of Sweet Sorghum under Salinity and Temperature Stresses

【作者】 Nimir Nimir； 周桂生； Shiyuan Lu； Fuyan Zhai； Wenshan Guo；

【Author】 Nimir Nimir;Guisheng Zhou;Shiyuan Lu;Fuyan Zhai;Wenshan Guo;Key Lab of Crop Genetics & Physiology of Jiangsu Province,Yangzhou Univ.;Joint Laboratory of Agricultural Sciences between Department of Agriculture and Agri-Food Canada and Yangzhou University,Yangzhou Univ.;

【机构】 Key Lab of Crop Genetics & Physiology of Jiangsu Province,Yangzhou Univ.； Joint Laboratory of Agricultural Sciences between Department of Agriculture and Agri-Food Canada； Yangzhou University； Yangzhou Univ.；

【摘要】 Sweet sorghum[Sorghum bicolor（L.Moench）],a drought tolerant crop,is characteristic of high sugar content in the juice of the stalks,from which ethanol can be easily produced and used as biofuel.For this reason,sweet sorghum has become a popular energy plant throughout the world.However,due to limited farming land,sweet sorghum is often grown in soils with medium to high salt concentrations.Salinity and high temperature are major abiotic stresses limiting sustainable crop production.Seed priming is a useful tool to enhance seedling growth and antioxidant defense system of crops under salinity and temperature stresses.The aim of this experiment was to determine the effects of GA₃（288.7 μM）,kinetin（232.2 μM）,and salicylic acid（362 μM） on some morphological and physiological parameters of sweet sorghum hybrid（Yajin 13） under different salinity（0,100 and 200 mM NaCl） and temperature（25℃ and 37℃） levels.Salinity and high temperature caused significant reductions in emergence percentage,shoot and root length,leaf number,shoot fresh and dry weight,and chlorophyll a and b content.The activity of SOD and malondialdehyde（MDA） content were increased due to the increase in both salinity and temperature stresses.Hormone treatments affected positively all parameters except root fresh and dry weight,leaf number,SOD activity,and chlorophyll a.Treatment with salicylic at 200 mM NaCl increased emergence percentage,emergence rate,chlorophyll b and protein content by 82.0%,130%,7.9%,and 1.9%respectively,than control at 200 mM NaCl.At 37°C,salicylic acid increased emergence percentage,emergence rate,and root number by 72.5%,108.5%,and 63.8%respectively,and decreased MDA content by 17.6%than the control at the same temperature.Our study indicated that seed priming with appropriate concentration of exogenous hormones like salicylic acid,kinetin,and GA3 is a useful and an easy method for improving germination,seedling growth,and antioxidant defense system of sweet sorghum under high temperature and salinity conditions.更多还原

【Abstract】 Sweet sorghum[Sorghum bicolor（L.Moench）],a drought tolerant crop,is characteristic of high sugar content in the juice of the stalks,from which ethanol can be easily produced and used as biofuel.For this reason,sweet sorghum has become a popular energy plant throughout the world.However,due to limited farming land,sweet sorghum is often grown in soils with medium to high salt concentrations.Salinity and high temperature are major abiotic stresses limiting sustainable crop production.Seed priming is a useful tool to enhance seedling growth and antioxidant defense system of crops under salinity and temperature stresses.The aim of this experiment was to determine the effects of GA₃（288.7 μM）,kinetin（232.2 μM）,and salicylic acid（362 μM） on some morphological and physiological parameters of sweet sorghum hybrid（Yajin 13） under different salinity（0,100 and 200 mM NaCl） and temperature（25℃ and 37℃） levels.Salinity and high temperature caused significant reductions in emergence percentage,shoot and root length,leaf number,shoot fresh and dry weight,and chlorophyll a and b content.The activity of SOD and malondialdehyde（MDA） content were increased due to the increase in both salinity and temperature stresses.Hormone treatments affected positively all parameters except root fresh and dry weight,leaf number,SOD activity,and chlorophyll a.Treatment with salicylic at 200 mM NaCl increased emergence percentage,emergence rate,chlorophyll b and protein content by 82.0%,130%,7.9%,and 1.9%respectively,than control at 200 mM NaCl.At 37°C,salicylic acid increased emergence percentage,emergence rate,and root number by 72.5%,108.5%,and 63.8%respectively,and decreased MDA content by 17.6%than the control at the same temperature.Our study indicated that seed priming with appropriate concentration of exogenous hormones like salicylic acid,kinetin,and GA3 is a useful and an easy method for improving germination,seedling growth,and antioxidant defense system of sweet sorghum under high temperature and salinity conditions.更多还原