石楠叶锈病菌Aecidium wenshanense锈孢子萌发的生物学特性

The biological characteristics of aeciospore germination of Aecidium wenshanense

为了解由文山春孢锈菌Aecidium wenshanense引起的石楠叶锈病的发生发展及流行规律,为病害的防治提供依据,本文以椭圆叶石楠Photinia beckii发病植株叶上的新鲜锈孢子为试验材料,采用水琼脂平板孢子萌发法对温度、湿度、光照、酸碱度及寄主汁液等条件对该锈孢子萌发的影响进行了研究。结果表明,该锈菌锈孢子在温度5~30℃和pH3~10的范围内都能萌发,最适温度为20~25℃;最适pH为6~8;相对湿度大于或等于90%时孢子才能萌发,最适湿度为100%+水;连续光照抑制孢子萌发,而连续黑暗条件下孢子萌发率最高。寄主(椭圆叶石楠)老叶的新鲜汁液对锈孢子的萌发有一定抑制作用。

Aecidium wenshanense is a pathogen causing rust disease of Photinia spp.,and it can seriously damage the leaves and twigs of host plant.In order to provide the basis for rust disease prevention and understand the regularity of disease development and epidemics,the effects of temperature,relative humidity(RH),light,pH and host plant juice on the aeciospore germination of the pathogen were studied by using the method of water agar plate surface germination.The results showed that the aeciospores could germinate in the range of 5-30℃and pH 3-10;the optimum temperature was 20-25℃,and the optimum pH was 6-8.However,the aeciospores could only germinate under the conditions of greater than or equal to 90%RH,and the optimum RH was 100%in water.Further studies found that the continuous illumination inhibited aeciospore germination,the germination rate was the highest under continuous darkness.To some extent,the fresh old leaf juice of P.beckii could inhibit aeciospore germination.