火烧迹地土千年健对麻栎化感作用及其机理研究

Allelopathy and Its Mechanism of Extract Solution of Vaccinium fragile on Quercus acutissimain Burned Forestlands

为探索火灾后化感作用对森林植被自然恢复的影响机制,选取滇中地区针阔混交林火烧迹地优势物种麻栎和土千年健,研究了土千年健水浸液对麻栎种子及其幼苗的化感作用和作用机理。结果表明:土千年健水浸液对麻栎种子萌发、麻栎幼苗主根长度及其鲜样质量和干样质量以及地上部分的高度及鲜样质量和干样质量的影响,呈现出低浓度促进,高浓度抑制的现象;随着土千年健水浸液浓度的增大,麻栎幼苗叶绿素含量逐渐降低,脯氨酸含量、丙二醛含量则逐渐升高,其对麻栎幼苗过氧化物酶活性的抑制作用也逐渐增强。研究发现,土千年健水浸液通过抑制保护酶活性和叶绿素的生成,增加膜脂过氧化伤害,抑制麻栎种子萌发和幼苗生长,从而表现出化感作用,且化感效应随着浓度的增加而增强。该研究为火灾后森林植被的人工恢复提供理论参考。

In order to explore allelopathic effects on its mechanism of natural regeneration in burned forestlands,allelopathy and its mechanism of extract solution of Vaccinium fragile on seed germination and seedling growth of Quercus acutissima were studied with the selection of the two dominant species of coniferous broad-leaved forest in burned forestlands in central Yunnan Province.The results showed that seed germination,main root length and its fresh weight and dry weight of seedling,and seedling height and its fresh weight and dry weight of Q.acutissima were increased at lower concentration and decreased at higher concentration of extract solution of V.fragile.Content of chlorophyll and POD activity of seedling of Q.acutissima were gradually reduced,but MDA content and Pro content of seedling of Q.acutissima were promoted with the increasing concentration of extract solution of V.fragile.It was found that allelopathy of extract solution of V.fragile on Q.acutissimain burned forestlands occurred with the activity of enzyme and content of chlorophyll and seed germination and seedling growth inhibited and the degree of membrane lipid peroxidation strengthened.So the research would give us advice on man-made regeneration in burned forestlands.