水稻种质对稗草和莴苣的化感效应研究

用改进的叶浸提法和田间共生鉴定法,比较分析了从124份不同来源水稻种质中初步筛选的27份化感种质对稗草和莴苣的化感抑制效果。结果表明,叶浸提液对莴苣的抑制效果明显大于稗草;对稗草和莴苣根长的抑制效果大于苗高和发芽势;叶浸提液法与田间共生法对稗草的抑制效果呈显著的正相关,两种方法的鉴定结果有较高的一致性。叶浸提液对稗草发芽势的抑制指数与田间共生对稗草苗干重的抑制指数及其综合抑制指数呈极显著的正相关,认为稗草种子发芽势可作为测试水稻种质化感效应的重要指标。田间水稻苗高与叶浸提液对稗草根长的抑制指数及其综合抑制指数和田间共生对稗草苗高和苗干重的抑制指数及其综合抑制指数呈极显著的正相关,水稻苗高较高的种质较苗矮的种质表现出较强的化感效应。珍珠42、沙粘1、六月早、青团2号、红脚粘2和地谷的化感效应突出,对稗草的平均综合抑制指数分别为0.56、0.47、0.45、0.45、0.41和0.39,可作为强化感种质提供应用。

Allelopathic Effect for Rice Germplasm on Barnyardgress and Lettuce

Allelopathic effect on barnyardgrass and lettuce for 27 accessions with allelopathic potential selected from 124 different rice germplasm were evaluated by the methods of extracting rice leaves and field test. The result demonstrated that the inhibitory effect on lettuce was more than that on barnyardgrass in the liquid of extracting rice leaves. The root length of barnyardgrass and lettuce was more inhibited than their seedling height and vigor germination. There was tight positive correlation between the methods of extracting rice leaves and field test on inhibitory effect, and the result of two methods had good consistency. The inhibitory index of vigor germination by treatment in the liquid of extracting rice leaves had prominently positive correlation with that of root length and its total inhibitory index in the method of extracting leaves, and that of seedling height, seedling dry weight and its total inhibitory index in field test, therefore the vigor germination of barnyardgrass was deemed a important index to evaluate allelopathic effect. Rice seedling height in field had prominently positive correlation with the inhibitory index on root length of barnyardgrass and its total inhibitory index in the method of extracting rice leaves, with the inhibitory index on seedling height and seedling dry weight of barnyardgrass and its total inhibitory index in field test. The taller rice germplasm had more allelopathic effect than the lower one. It standed out in the allelopathic effect for Zhenzhu 42, Shazhan 1, Liuyuezao, Qintuan 2, Hongjiaozhan 2 and Digu, and their mean total inhibitory indices on barnyardgrass were 0.56, 0.47, 0.45, 0.45, 0.41 and 0.39, respectively, which can be used as germplasm with strong allelopathic effect.