摘要
采用 32 P示踪和 4室根箱方法研究了外生菌根菌丝桥对板栗磷营养和植株间磷素传递作用的效应。给一株板栗幼苗 (供体 )接种外生菌根真菌美味牛肝菌 ( Boletusedulis)、褐环乳牛肝菌 ( Suillusluteus) ,菌根真菌在侵染供体植物以后其根外菌丝继续生长并侵染邻近的另外一株板栗植株 (受体 )。同位素示踪试验表明 ,供体板栗体内的 32 P可通过菌丝桥传递给受体板栗 ,受体植株不仅根中 32 P放射性强度高于对照 ,而且茎中32 P强度也显著高于对照。说明外生菌根真菌在不同板栗植株间形成了菌丝桥 ,但是菌丝桥传递的磷的数量很有限 ,仅占供体植株体内总磷量的 5 %～ 8%。美味牛肝菌和褐环乳牛肝菌侵染供体板栗植株以后 ,使植株含磷量、总吸磷量和生物量较对照明显增加。受体板栗幼苗在菌丝桥建立以后其植株含磷量和总吸磷量显著高于对照 ,但生物量与对照没有显著差别。
Chestnut is an important cash special olcal product in Beijing which is exported to many foreign countries.The tree were grown along Yanshan mountain where the soil fertility is very poor because the farmer do not apply fertilizer.Therefore ectomycorrhizal fungi may play important role to the growth of the tree.In orde r to understand the improvement of phosphorus status in plant by inoculating wit h ectomycorrhizal fungi and the phosphorus transferring between chestnut seedlin gs via hyphal link,a four compartmented box was developed.Each box was separated into two outer compartments for growth of donor plant and receiver plant,and tw o central compartments for external mycelium using 30-μm nylon mesh to restric t the roots but allow hyphal penetration.On the bootom of the compartment for do nor plant,there was a small hole which were opened six month after transplanting . The root of donor plant was induced to go out of the box through the hole.Solu tion contained ３２P was supplied to the root,and the donor plant was labeled.One central compartment was filled with clay soil as a barrier to reduc ed the diffusion of 32P in substrate.All other three compartments were filled with a substrate of mixture of soil,charcoal and river sand in 2∶1∶1 ( w/w).Donor plant was inoculated with two ectomycorrhizal fungi,Boletus edulis an d Suillus luteus,or non-inoculated (control).The results showed that extraradic al mycelium of donor chestnut plant inoculated with Boletus edulis and Suillus l uteus penetrate clay soil and then colonized receiver plant.３２P acti vity in receive plant colonized by both mycorrhizal fungi was higher than that o f in control plant.This indicated that the hyphal links were formed between do no r and receiver chestnuts seedlings.The donor plant inoculated Boletus edulis and Suillus luteus was greater in biomass than non-mycorrhizhl plant,while the gro wth of receiver plant was not significantly affected by the colonization of both fungi.Comparing to non-inoculating treatment,the colonization of the two fungi on donor plant and receiver plant increased their P concentration and P uptake. The hyphal links between two chestnut plants transferred 5 to 8 percent of total phosphorus untaken by donor plant to receiver plant.It is concluded that inocul ating of both ectomycorrhizal fungi improved the P untrition of donor plant,the phosphorus absorbed by donor plant can be transferred to receiver plant through the hyphae bridges although the transferring rate was relatively lower.rmed
出处
《生态学报》
CAS
CSCD
北大核心
2003年第4期765-770,共6页
Acta Ecologica Sinica
基金
国家自然科学基金资助项目 ( 39970 1 39)
北京市重点基金资助项目 ( 6982 0 0 9)。~~
