芦苇水提液对加拿大一枝黄花生长及光合作用的化感效应

Allelopathic effects of aqueous extracts from Phragmites communis on the growth and photosynthesis of Solidago canadensis

以芦苇叶为化感供体材料,采用砂培法研究其不同浓度[0(CK)、0.025 g·mL-1(2.5%)、0.05 g·mL-1(5%)和0.1 g·mL-1(10%)]水提液对入侵植物加拿大一枝黄花生长及光合生理特征的化感效应。结果表明:芦苇叶水提液对加拿大一枝黄花株高和生物量的影响表现为低浓度无明显作用,高浓度抑制;低浓度处理对光合速率和气孔导度无显著影响,但高浓度处理则使二者明显降低,并缩短了叶片有效光合功能期;水提液对叶绿素含量、最大净光合速率、光饱和点和表观量子效率有明显的"低促高抑"的效应,类胡萝卜素含量则随水提液浓度的升高而上升,各处理暗呼吸速率均显著高于对照,但随浓度升高有下降的趋势。可见,芦苇化感作用可以通过影响加拿大一枝黄花的光合作用,包括叶绿素含量、叶片气孔开放程度以及植物对光照的响应能力等方面,进而对其生长产生影响。

Allelopathy Of aqueous extracts from Phragmites communis leaves on the growth and photosynthetic physiological characteristics of invasive plant Solidago canadensis was determined at different concentrations [0 （CK）, 0.025 g·mL^-1（2.5% ）, 0.05 g·mL^-1（5% ） and 0.10 g ·mL^-1 （ 10% ） ]. The results showed that the height growth and biomass, net photosynthetic rate and stomatal conductance were not inhibited by the low concentration （2.5%） of leaf ex- tracts, but were significantly inhibited at the high concentration （ 10% ）. The chlorophyll con- tent, light saturation point and apparent quantum efficiency were promoted by the low concentra- tion of extracts hut inhibited by the high concentration. With the extract concentration increasing, carotenoids content increased gradually, and the dark respiration rate decreased gradually but was significantly higher than CK. Therefore, allelopathy of P. communis on the growth of S. cana- densis was found through affecting photosynthesis, including chlorophyll content, leaf stomatal openness and the light response capability.