土壤环境因素对水稻纹枯病菌腐生定殖能力的影响

 研究了土壤含菌量、温度、含水量和pH值对水稻纹枯病菌在土壤中腐生定殖能力的影响。研究结果表明:土壤含菌量越大,腐生后的定殖率越高,但未达到腐生处理前的水平;随着腐生温度的升高,定殖率逐渐下降,当腐生温度达到40℃时,定殖率迅速下降到8.0%;土壤含水量在15%时腐生能力最强、定殖率最高,达到84.0%,而在土壤含水量较大或较小时腐生定殖能力都不高;另外,该病菌喜好酸性的土壤环境,在pH6.0时腐生能力最强、定殖率最高,达到85.3%。

THE EFFECTS OF SOIL ENVIRONMENTAL FACTORS ON THE SAPROPHYTIC COLONIZATION OF Rhizoctonia solani

The effects of soil inoculum level, temperature, moisture content and pH value on the saprophytic colonization of Rhizoctonia solani Kühn were studied. The results showed that the higher the inoculum level, the higher the rate of saprophytic colonization, but not reaching to the level of untreated control. With the increasing of temperature, the rate of saprophytic colonization decreased, and when the soil temperature reached to 40℃, the rate of saprophytic colonization dropped to 8.0% quickly. The rate of saprophytic colonization reached to 84.0%, the highest at 15% soil moisture content, whereas the rate of saprophytic colonization was low either at over or below this soil moisture content. In addition, the pathogen preferred the acid soil environment, and the highest rate of saprophytic colonization was 85.3% at pH 6.0.