遮荫对广东西部香根草光合特性及生长的影响

Effect of shading on photosynthesis characteristics and growth of Vetiveria zizanioides in western Guangdong

研究了不同遮荫(0%,75%和94%)条件下对广东西部香根草光合特性和生长的影响。结果表明:遮荫导致叶片的光合速率下降,香根草光饱和点(LSP)和光补偿点(LCP)也有所降低,94%遮荫处理的光补偿点与对照差异极显著(P<0.01),但是遮荫对表观量子效率(AQY)却有不同程度的提高。遮荫使香根草叶片中叶绿素a、叶绿素b和总叶绿素含量显著增加,75%和94%遮荫处理的叶绿素总量分别比对照增加了23.28%和19.40%。遮荫也使香根草的植株含水量显著(P<0.05)增加,并且94%遮荫与对照差异极显著(P<0.01)。

The effect of 3 levels of shading （0,75% and 94% shading） on physiological characteristics and growth of Vetiveria zizanioides in the western Guangdong was studied. The results showed that the shading treatment decreased the photosynthesis rate. It also caused a decrease of light saturation point（LSP）and the light compensation point （LCP）to some degree,and the light compensation point（LCP）was significantly different （P（0.01） between the 94 ; shading treatment and the control,but the apparent quantum efficiency （AQY） was increased by shading. The content of chlorophyll （chlorophyll a and b and total） was increased significantly under shading,and total chlorophyll content in 75 ; and 94 % shading treatments were increased by 23.280; and 19.40% compared to the control （2.01 mg/g） respectively. The plant height and tiller number were decreased by shading treatment （P（0.05）, but water content of plant was increased （P〈0.05） and the difference between 94% shading treatment and the control was significant （P〈0.01）.