关键词: 干旱胁迫, 大豆品种, 根系形态, 抗旱性

Abstract: In order to clarify the effect of drought stress on physiological characteristics and plant growth parameters of soybean cultivars with different drought resistance, this experiment took drought resistant variety (RD) and drought sensitive variety (SD) as material to analyze the effects of water stress on physiological and biochemical indexes and growth parameters of soybean during development period by pot cultivation method. The results showed that the physiological and biochemical indexes of RD and SD were not significantly different under normal water conditions. While after 15 d with drought stress, the activities of SOD and POD in RD plant leaves were 1.34～1.45 fold and 46～1.69 fold of that in SD, respectively. The hydrogen peroxide (H2O2) and malondialdehyde (MDA) in SD plant leaves were 1.80～2.35 fold and 1.09～1.46 fold of that in RD, respectively. In addition, under drought stress, the root biomass both above and below ground of RD was significantly higher than that of SD, and its root morphology parameters were much better than that of SD. The experimental results showed that for reponsing to drought condition, the drought resistant variety RD adjusted its body physiological changes, and optimized the parameters of root morphology to ensure the normal growth of plant and improve its responsing ability to drought stress.

Key words: drought stress, soybean variety, root system morphology, drought resistance