北方蜜环菌菌索生长、发育对环境氧气及土壤湿度的响应

Response of Armillaria borealis rhizomorph growth and development to environmental oxygen and soil humidity

蜜环菌属Armillariaspp.真菌是重要的植物病原菌和兰科Orchidaceae植物天麻Gastrodia elata的专性共生菌,能以菌索形式在土壤中存活和传播,因此,土壤环境变化对蜜环菌菌索生长、发育的影响,是关系天麻栽培和森林蜜环菌病害的重要过程。为了揭示蜜环菌生长发育对土壤水分和氧气的适应特征,本研究以北方蜜环菌Armillaria borealis为研究材料,设计氧气浓度5%、15%、20%和30%的4个水平与土壤湿度20%、40%、60%和80%的双因素实验,在室内24℃及黑暗条件下培养,观察菌索发生时间(T)、测定菌索生物量(DW)、菌索长度(L)、菌索数(Nt)、菌索分枝数(Nf)和菌索直径(AD)。结果表明,土壤湿度和氧气浓度对北方蜜环菌菌索发育和生长具有显著影响,在15%的氧气浓度和60%的土壤湿度发育最快。本研究为人工模拟蜜环菌生长发育的环境提供了部分依据,对提高天麻人工栽培的产量,揭示森林蜜环菌病害发病机制具有重要价值。

Armillaria spp.are important plant pathogen and symbiotic fungi of Gastrodia elata,which can spread in soil in the form of rhizomorph.The influence of soil environmental changes on the growth and development of Armillaria rhizomorph is an important process related to forest Armillaria disease and Gastrodia elata production.In this study,Armillaria borealis was selected as material,and a two-factor experiment was designed to test the effects of oxygen and soil humidity on development and growth of A.borealis rhizomorph.Four oxygen concentration levels(5%,15%,20%and 30%)and four soil humidity levels(20%,40%,60%and 80%)were designed.The rhizomorph of A.borealis were cultured in chambers under dark and 25°C condition,then the occurrence time(T)of rhizomorph was observed,and the rhizomorph dry weight(DW),rhizomorph length(L),rhizomorph number(Nt),rhizomorph branch number(Nf),and rhizomorph average diameter(AD)were determined.The results showed that oxygen and soil humidity had a significant effect on the development growth of A.borealis rhizomorph.The fastest growth and development were presented under oxygen concentration of 15%and soil humidity of 60%.This study provided some referential data for artificial control of the growth and development of A.borealis,and improving the yield of Gastrodia elata cultivation.