致病产毒禾谷镰刀菌株的保存方法

STUDY ON PRESERVATION METHOD FOR PATHOGENIC AND TOXIGENIC ISOLATES OF Fusarium graminearum

致病产毒禾谷镰刀菌株接种于麦穗和麦粒,存放于干燥器内,置4℃冰箱内可保存13年之久。菌株的每代菌丝体和分生孢子存活率为100％;培养性状及产孢能力正常。接种中感小麦品种,寄主病害反应级数2.9—3.3;液体菌株产毒量1.08—1.45μg/ml,每代的致病性和产毒性均无显著差异。采集田间病穗在4℃冰箱保存7年,其菌丝体和分生孢子存活率为100％,但保存到13年,存活率分别下降到55.6％和77.8％。以麦穗和麦粒为保存基质,方法简便易行。

It has been studied the preservation method for the pathogenic and toxigenic isolates of Fusariun graminearum. The results showed that the isolates inoculated on wheat spikes and grains stored in dryers could be preserved at 4℃ for 13 years. The survival rate of mycelia and eonidia was 100% for every generation of the isolates, Their culture characteristics and ability to sporulate at perfect and imperfect stages were normal. The means of disease reaction indices were 2.9—3.3 on the moderately susceptible wheat variety after inoculation with the isolates. The amounts of deoxynivalenol produced by the isolates were 1.08—1.45 μg/ml in liquid culture. There were no significant differences in pathogenicity and toxigenicity among the isolate generations. When the isolates from field-coUeeted diseased spikes Were preserved for 7 years at 4℃, the-survival rate was 100% for both the mycelia and conidia of isolates; when the isolates were preserved for 13 years, the survival rates for mycelia and conidia were 55.6% and 77.8%, respectively.Therefore, of the isolates could be preserved for long term using wheat spikes and grains as preservation substrates at low temperature and in dry conditions. The preservation method was simple, applicable and easy to popularize.