Effects of uniconazole soaking on drought tolerance of soybean seedling

In order to understand the effects of uniconazole on drought tolerance of soybean seedlings,germination rate,morphological and physiological characteristics were studied using uniconazole soaked soybean cultivar Zhechun3 under different water stress.The result showed that seedling height was decreased,but germination rate,stem diameter and root to shoot ratio were increased after soaking.Relative water content,proline and soluble sugar were increased.Meanwhile,MDA(malondiadehyde) content was decreased followed by lipid peroxidation,although protective enzyme activity increased.The best response of the protective enzymes,including SOD(superoxide dismutase),POD(peroxidase) and CAT(catalase),increased up to 18.75%,8.43% and 37.4% under 0.1mg/kg uniconazole with normal irrigation,and up to 23.53%,11.63% and 47.5% under 0.2mg/kg uniconazole with slight water stress,and up to 22.86%,11.2% and 56.1% under 0.4mg/kg uniconazole with medium water stress,respectively.The results suggested that seed soaking with uniconazole at a suitable concentration could improve soybean seedling growth and strengthen seedling establishment during drought.