不同遮荫程度对假俭草光合特性和抗氧化能力的影响

摘要

The photosynthetic characteristics and antioxidant capacity of centipedegrass under different shad-ing levels (50% and 70% of full sunlight)were studied.The results indicated that compared with the control (full sunlight),the contents of chlorophyll a and b were significantly increased,particularly at 50% shading lev-el,however,the net photosynthetic rate (P n )and light saturation point (LSP)in leaf were deceased.No signifi-cant changes were observed in MDA content and chlorophyll a/b ratio.With increase of shading level,SOD ac-tivity was decreased correspondingly,the leakage of electrolytes was increased.And the accumulation free pro-line was reduced.It could be concluded that antioxidant capacity of centipedegrass was decreased when growing in shading environment.%试验以50%和70%遮荫下生长的假俭草为材料,研究了不同遮荫程度对假俭草光合特性和抗氧化能力的影响。结果表明：与全光照相比,2种遮荫处理,尤其50%遮荫,显著地提高了叶绿素 a 和叶绿素 b 含量,而叶片净光合速率及光饱和点发生了降低,相比而言,丙二醛含量和叶绿素 a/b 比值没有发生显著变化。另外,随着遮荫强度的加大,超氧化物歧化酶活性不断降低,电解质外渗率不断增加,而脯氨酸的积累则显著减少、说明遮荫下植株的抗氧化能力降低。