葛藤(Puerraria lobata)根际AM真菌生态学研究

2004年7月至12月每月中旬分别从0~10,10~20,20~30和30~40 cm土层采集根际土样,对陕西武功县葛藤根际AM真菌进行了系统的生态学研究.结果表明,AM真菌的分布和定殖与时间变化密切相关,菌根真菌的最高定殖率伴随有最大的孢子密度,最高值都出现在2004年11月.土壤pH值与泡囊定殖率呈极显著负相关.孢子密度与泡囊定殖率呈显著正相关,速效磷与泡囊定殖率呈显著负相关;碱解氮与孢子密度、总定殖率、泡囊、菌丝定殖率呈极显著负相关.在检测和评估土壤生态状况和植物形成菌根能力等方面,AM真菌孢子密度和不同结构定殖程度是十分有用的指标,尤其是泡囊定殖率可作为葛藤优化盐碱地状况的重要指标.土样中AM真菌多为球囊霉属(Glomus)种类,也有少数无梗囊霉属(Acaulospora)和盾巨孢囊霉属(Scutellospora)的种类.

Ecological Research of Arbuscular Mycorrhizal Fungi in Rhizosphere of Puerraria lobata

Soil samples from 0～10,10～20,20～30 and 30～40 cm depths were collected monthly between July and December 2004 under the canopy of Puerraria lobata in Wugong,Shaanxi.The result showed that fungi distribution,colonization is closely related with the time.The mean percent colonization and spore density of AM fungi reached maximal values in November 2004.Soil pH value had a significant negative correlation with vesicular percent colonization.Spore density had appositive effect on vesicular percent colonization.Soil available P had a negative correlation with vesicular percent colonization.Soil alkali solution N had a negative effect on spore density and total percent colonization.Our results support the opinion that spore density and different structures of AM fungi in the rhizosphere of Puerraria lobata are useful indicators for evaluating changes in soil ecosystems,especially the vesicular percent colonization are the useful indication for evaluating changes in saline-alkaline soil.