幼苗期不同水稻材料应答盐胁迫的生理差异分析

为了解耐盐水稻HD96-1幼苗期耐盐生理调控特性，该研究以籼型水稻HD96-1(耐盐性强)和93-11(耐盐性弱)为材料，采用营养液水培法，设置3种NaCl盐浓度(0、60、120 mmol·L^-1),对3叶期幼苗进行了7 d盐处理，测定和分析了两个材料的生长参数和生理生化指标。结果表明：(1)在盐胁迫下，水稻幼苗均表现为株高和假茎宽减小，根冠比增加；与93-11比，HD96-1株高和茎宽减小幅度低，根冠比增加幅度高；地上部和根系干重，HD96-1增加，而93-11减少。(2)盐胁迫后，水稻幼苗的丙二醛(MDA)、超氧阴离子(O₂^-)和过氧化氢(H₂O₂)含量均上升，但HD96-1增幅较93-11低。(3)在盐胁迫下，水稻幼苗体内的超氧化物歧化酶(SOD)、过氧化物酶(POD)、过氧化氢酶(CAT)、抗坏血酸过氧化物酶(APX)的活性，以及抗坏血酸(AsA)、谷胱甘肽(GSH)、脯氨酸、可溶性糖和可溶性蛋白的含量均升高，HD96-1增幅高于93-11。综上表明，两个水稻材料幼苗...

Physiological differences of different rice materials in response to salt stress at seedling stage

In order to investigate physiological characteristics of salt-tolerance rice HD96-1 at seedling stage, indica rice HD96-1(strong salt-tolerant)and 93-11(weak salt-tolerant)were used as experimental materials in this study. Three NaCl concentrations(0, 60, 120 mmol·L^-1)was set to treat 3-leaf rice seedlings for 7 d. The growth, physiological and biochemical indexes of two rice cultivars were measured and analyzed. The results were as follows:(1)The plant height and the pseudostem width of two cultivars decreased, and the root-shoot ratio increased under salt stress; compared with 93-11, the decrease of plant height and pseudostem width of HD96-1 was lower, and the increase of root-shoot ratio was higher under salt stress; in addition, the dry weight of aboveground and root of HD96-1 increased under salt stress, while that of 93-11 decreased.(2)The malonaldehyde(MDA), superoxide anion(O₂^-)and hydrogen peroxide(H₂O₂)contents in rice seedlings increased after salt stress, of which the increase of HD96-1 was lower than that of 93-11.(3)The activities of superoxide dismutase(SOD), peroxidase(POD), catalase(CAT)and ascorbate peroxidase(APX), the contents of ascorbic acid(AsA), glutathione(GSH), proline, soluble sugar and soluble protein in rice seedlings were increased under salt stress, of which the increase of HD96-1 was higher than that of 93-11. In conclusion, the physiological mechanisms of two rice seedlings responding to salt stress are similar, but the difference is that HD96-1 with strong salt-tolerance is stronger antioxidant and osmotic regulation ability than 93-11 in response to salt stress, so that growth and development of HD96-1 are less inhibited than 93-11.