环境因子对马铃薯致病立枯丝核菌AG-3融合群生长的影响

目的]研究环境因子对马铃薯致病立枯丝核菌AG-3融合群生长状况的影响,以明确黑龙江省马铃薯立枯丝核菌的环境适应性,为该病害的防治提供理论依据。方法]采用生长速率法对立枯丝核菌菌丝在不同温度、p H、光暗条件下的生长状况进行测定。结果]菌丝在4℃条件下不能生长,适宜温度为19~25℃,全暗和全光条件下最适生长温度分别为22和25℃,黑暗条件有利于菌丝生长;在p H 4~11时菌丝均能生长,以p H 6~7时菌丝生长速度较快;当热激20 min以上时,其致死温度为50℃。结论]综合评价了环境因子对立枯丝核菌AG-3融合群生长的影响,同时耐热性测定表明短暂热激对菌丝生长有一定的促进作用,但当时间过长或温度过高时会严重抑制菌丝的生长。

Influence of Environmental Factors on Growth Status of AG-3 for Potato Pathogenic Rhizoctonia solani

Objective] The aim was to study effects of environmental factors on the growth status of anastomosis group AG-3, to determine envi-ronmental adaptation of Rhizoctonia solani from Heilongjiang Province, which provides a theoretical basis for control of the disease. Method] The growth status of Rhizoctonia solani under different conditions of temperature, pH and light was determined by growth rate method. Result] The mycelium could grow under the setting temperature except 4 ℃, the optimal temperature was 19-25 ℃, and the fastest growth under the condition of dark and light was 22 and 25 ℃ respectively, and the growth of mycelia was accelerated by darkness.The range of pH was 4-11, and the optimal pH for growth was 6-7.Meanwhile, the lethal temperature was 50 ℃ after heat shocking more than 20 minutes. Conclusion] The effect of environmental factors on the mycelial growth of AG-3 is comprehensively evaluated, and determination of heat resistance indicates that there is a promotion on mycelial growth by heat shocking when the time and temperature is not too long or too high.