空心莲子草各器官水提液对小白菜化感作用的综合评价

Comprehensive Evaluation of Allelopathic Effects of Water Extract from Alternanthera philoxeroides on Brassica chinensis

为了解空心莲子草不同器官的化感作用,本研究采用培养皿滤纸法研究了空心莲子草根、茎、叶和花水提液对小白菜种子萌发、根长、苗高和幼苗鲜重的影响。结果表明,小白菜种子萌发率、根长、苗高以及幼苗鲜重在空心莲子草水提液中均表现出低浓度促进,高浓度抑制的效应;随着水提液浓度的增加,小白菜种子萌发率、根长、苗高以及幼苗鲜重呈逐步减小趋势;随着时间的推移,空心莲子草水提液处理的小白菜根长、苗高呈上升趋势。种子萌发率在第2-3 d达到最大值,而后下降,幼苗鲜重则高浓度逐步下降,低浓度逐步上升趋势;小白菜幼苗根长受空心莲子草水提液影响严重,化感效应指数达0.73,而幼苗高度仅为0.29 cm;空心莲子草根水提液对小白菜萌发率、根长、苗高以及幼苗鲜重抑制作用最强,花水提液抑制效果最差。

In order to know the allelopathy effect of different organs of Alternanthera philoxeroides, seeds of Brassica chinensis were treated by water extracts of fresh root, stem, leave and flower of A. philoxeroides at different concentration in Petri dish. The results showed that the water extract of different parts of A. philoxeroides all promoted the seed germination, root length, seedling height and fresh weight of B. chinensis at lower concentration, root length and seedling height of B. chinensis treated by water extracts from A. philoxeroides increased with time going, and the seed germination reached the maximum in the 2 or 3 day, and then decreased. The fresh weight decreased gradually at higher concentrations, and rose gradually at lower concentrations. The root length of B. chinensis was influenced seriously by the water extract of A. philoxeroides, and the allelopathic effect index reached 0.73, but the index of the seedling height reached 0.29 cm only. The seed germination, root length, seedling height and fresh weight of B. chinensis were strongly inhibited by the water extract of A. philoxeroides root, and that of A. philoxeroides flower was the worst.