硒对水稻光合作用及抗氧化作用的影响

硒是植物非必需营养元素,但是适量的硒对植物生长有着促进作用。通过研究硒对水稻光合作用及抗氧化作用的影响为硒对水稻生长的促进作用提供依据。采用盆栽试验,研究不同施硒浓度(0~5 mg/kg)对水稻产量、硒含量、叶绿素含量、光合参数、抗氧化酶活性及细胞膜透性的影响。结果表明,施硒显著提高了水稻产量,在1.0和5.0 mg/kg施硒水平较对照(不施硒)分别增产20.8%和28.8%。施硒提高了水稻谷壳、大米、秸秆及根中硒的含量。施硒对水稻叶绿素a和叶绿素b含量影响不大,但在5.0 mg/kg施硒水平上显著增加了水稻类胡萝卜素含量。施硒显著增加了叶片胞间二氧化碳浓度、蒸腾速率和光合速率,最高增幅分别为28.4%、26.1%及25.0%。施硒显著降低了水稻叶片离子渗漏量及相对电导膜透性。施硒显著增加了超氧化物歧化酶(SOD)、过氧化物酶(POD)和过氧化氢酶(CAT)的活性,最高增幅分别为101.2%、23.4%和64.3%。试验结果表明,硒能增强水稻的光合作用及抗氧化作用,从而达到了促进水稻生长的效果。

Effects of selenium on photosynthesis and antioxidation of rice

Selenium is not an essential element for plants,but optimal Se can stimulate growth of plants.In this paper,the effects of different concentration of Se (0 ～ 5 mg/kg) on the Se content,grain yield,chlorophyll content,photosynthesis,antioxidation and cell permeability in rice were studied in pot experiment to clarify the impact of Se on rice growth.Result showed that 1.0 and 5.0 mg/kg Se treatment significantly increased the grain yield by 20.8％ and 28.8％.The application of Se increased the Se concentration in husks,rices,staws and roots of rice plants.chlorophyll a and chlorophyll b contents were unaffected by Se application,however,the content of carotenoids was significantly increased in 5.0 mg/kg Se treatment.The application of Se increased the intercellular CO2 concentration,the transpiration efficiency and the photosynthesis rate of rice,the highest value were increased by 28.4％,26.1％ and 25.0％,respectively.Se treatment significantly decreased the electrolyte leakage and relative conductivity of rice.The application of Se significandy increased the activities of superoxide dismutase,peroxidase and catalase of rice,the highest values were increased by 101.2％,23.4％ and 64.3％,respectively.This study indicated that selenium promoted the growth of rice by enhancing photosynthesis and antioxidation.