菩提树黑痣病菌生物学特性及病害发生规律

为了研究菩提树黑痣病的年发生规律、病原菌子囊孢子释放规律及子囊孢子萌发的生物学特性,利用样地调查和实验室测定方法,对广西凭祥市菩提树黑痣病进行了调查。结果表明:菩提树黑痣病病情指数增长量与平均降水量和平均空气相对湿度呈极显著关系,与温度变化呈显著关系,与平均相对孢子捕捉量呈不显著关系。菩提树黑痣病病情指数增长盛期在4-8月,增长高峰期为6月;室外子囊孢子捕捉量在6月、10-11月出现2个高峰期;菩提树黑痣病菌子囊孢子萌发的最适生长温度为25℃,子囊孢子萌发要求的最低空气相对湿度为90%,3种碳源处理都无法刺激子囊孢子萌发,而3种氮源中的硝酸钠处理可以刺激其萌发。

Biological characters of Phyllachora repens and occurrence regularity of tar spot of Ficus religiosa

To understand occurrence regularity of tar spot of Ficus religiosa,ascospores released in a year and the biological characters of the ascospres,a survey on tar spot of F.religiosa in Pingxiang of Guangxi was carried out through sampling in field and testing in lab.The result showed that the increase of disease index of tar spot was significantly correlated with average rainfall and relative air humidity,and was obviously correlated with temperature change.It was not significantly correlated with the average relative ascospore capture.The peak period of disease increase was between April to August and the maximum increase was in June;the two peaks of outdoor ascospore capture occurred in June and from October to November;the optimum germination temperature of ascospores was 25 ℃.The lowest germination humidity of ascospores was 90%;the germination of ascospores could not be stimulated by all 3 carbon sources,but could be stimulated by sodium nitrate after ascospores were treated with 3 nitrogen sources.