江苏麦类禾谷镰刀菌变异性的研究

1980～1981年选取代表江苏不同地区引致麦类赤霉病的禾谷镰刀菌野生型和培养型菌株17个,并人工移植1～3次后,观察培养性状的变化;同时分别接种感病小麦品种“矮秆早”,观察致病性的变化,以分析病菌的变异性。结果证明:江苏极大多数禾谷镰刀菌菌株的野生型经人工移植三次后,无论是培养性状和致病力都发生了改变。一般表现力生长速度减慢,产孢数量变少,产孢速度变慢,分生孢子变小,分生孢子分隔数减少,不易产生分生孢子或不产孢,不易形成子囊壳或不产生子囊壳而产生粘孢团,以及致病力减弱。但是,只有少数菌株的变异特别明显。以上结果说明禾谷镰刀菌菌株中存在有变异现象,但不同菌株并不一致,培养性状变异与致病力强弱变异间的关系也可能因菌株而异。至于禾谷镰刀菌在无性培养中发生变异的原因还有待进一步研究。

A STUDY ON VARIATION OF FUSARIUM GRAMINEARUM SCHW. IN JIANGSU

In 1980~1981,the variation of cultural characteristics in 17 wild-type and culture-type isolates of Fusarium graminearum collected from different parts in Jiangsu were observed after being transplanted or one to three times.A disease-free early-maturing dwarf wheat rarity "Aikenzhao" which is susceptible to wheatscab was inoculated with these 17 isolates respectively to detect the variation of pathogenicity.The results obtained proved that changes in both cultural characteristics and pathogenicity were found in most of the isolates,with in them a few such as F₄₇ significantly varied,after being transplanted for 3 times.It can be generally expressed that growth rate reduced;sporulaion slowly or difficultly occurred;conidia decreased and minimized;septa decreased or no conidia produced;perithecium difficultly or no perthecium produced but pa-thogenicity weakened.