拉关木浸提液对红海榄胚轴萌发和幼苗生长的化感作用

Allelopathic Effects of Laguncularia racemosa Aqueous Extract on Hypocotyl Germination and Seedling Growth of Rhizophora stylosa

为探究外来红树拉关木Laguncularia racemosa对乡土红树红海榄Rhizophora stylosa的化感作用,研究通过室内栽培试验,分别用低浓度(0.1 g·mL^(-1))、中浓度(0.3 g·mL^(-1))、高浓度(0.5 g·mL^(-1))的拉关木根水浸提液和叶水浸提液对红海榄胚轴和幼苗进行处理。结果显示:拉关木根水浸提液对红海榄胚轴萌发的化感作用为“低浓度促进高浓度无影响”,对幼苗生长则表现为“无影响”;叶水浸提液对红海榄胚轴萌发有“低浓度促进高浓度抑制”的化感作用,以及对幼苗生长整体表现为“低浓度无影响高浓度抑制”的化感作用;对于红海榄幼苗叶片酶活性(SOD、POD)的影响,仅中等浓度拉关木根水浸提液对红海榄幼苗POD活性有显著的抑制效应。

To explore the allelopathic effect of the exotic mangrove Laguncularia racemosa on the native species Rhizophora stylosa,the hypocotyl and seedling of R.stylosa were treated with low concentration(0.1 g·mL^(-1)),medium concentration(0.3 g·mL^(-1)),high concentration(0.5 g·mL^(-1))of water extract from roots and leaves of L.racemosa through indoor cultivation experiments.The results showed that the allelopathic effect of root aqueous extract on the germination of R.stylosa hypocotyl was promoted at low concentrations and not affected at high concentrations,and the effect on seedling growth was“no effect”.The leaf aqueous extract had the allelopathic effect of“low concentration promotion but high concentration inhibition”on hypocotyl germination of R.stylosa,and the overall allelopathic effect of“no effect of low concentration and high concentration inhibition”on seedling growth of R.stylosa.For the effect of leaf enzyme activity(SOD,POD),only the moderate concentration of L.racemosa root aqueous extract had a significant inhibitory effect on the POD activity of R.stylosa seedlings.