摘要：职称论文发表在江西九连山国家级自然保护区内毛红椿3个天然优势群落（大丘田、电站、虾公塘），分别取林下土即距离毛红椿结实母株和非结实母株的2.5 m、5 m、7.5 m处的根区土壤和远离同种大树的非根区土壤，以非林地土（新鲜河沙、沙壤土和菜地土）为对照，通过实验室模拟播种和真菌感染实验，来探讨不同土壤对毛红椿种子萌发和幼苗保存的影响。结果表明：九连山毛红椿天然群落林下土对种子发芽无显著差异，但幼苗保存率显著低于非林地土；根区土的毛红椿幼苗死亡速度快于非根区土，幼苗存活率显著低于非根区土；距母树3个不同距离或母株结实与否等根区土的幼苗存活率差异均不显著；根区土壤真菌RS2、RS5为幼苗潜在致病菌，根系分泌物和致病菌的互作能够显著降低幼苗保存率。
关键词： 毛红椿；种子萌发；幼苗存活;土壤真菌

GUO Xiaoyan^1,， ZHANG Lu^2,*， SU Heng^3,， LIANG Yuelong^2,

 

Abstract： To find out the reason of the difficulty in natural regeneration of Toona ciliata var. Pubescens, soil samples were collected from root zone of the species' fruiting on-fruiting trees as well as far away from the trees in its three different natural forest stands (Daqiutian、Dianzhan、Xiagongtang) in Jiulianshan National Nature Reserve. Seed germination trials on soils were carried out in the laboratory with non forest soil (sand, sandy soil, vegetable soil) as the control. Seedling cultivation trials in soils were carried out in laboratory with root irrigation by fungal spore suspension and root exudates to study the effects of root zone soil fungi RS2, RS3, RS5 on seedling survival of T. ciliata var. Pubescens. The results show that there are no significant differences between forest soil and non forest soil in germination rate，but seedling survival rate was significantly lower than that of non forest soil; The seedlings in root zone soil died sooner than those in non root zone soil and its survival rate is significantly lower than that of non root zone soil; There was no significant difference in seedlings survival rate of root zone soil between any two of 3 different distances from its mother trees as well as between fruiting and non-fruiting trees ; Soil-borne fungi RS2 and RS5 were potential pathogens, and the interaction between root exudates and pathogens could significantly reduce the seedling survival rate.
Keywords： Toona ciliata var. Pubescens;seed germination; seedlings survival;soil-borne fungal