河北省小麦冠腐病发生现状及病原菌初探

2013-2015年对河北省小麦主产区65县124点小麦冠腐病的田间症状和发生情况进行了调查。该病主要引起小麦茎基部变褐,灌浆期引起枯白穗,对产量影响较大。调查结果表明,小麦冠腐病发生主要集中在河北省中南部地区,而且发生程度呈逐年加重的趋势。2013年田间很少见由小麦冠腐病引起的枯白穗,2015年田间普遍发生枯白穗,严重发生地块局部枯白穗率达到20%~50%。病原菌分离结果显示,河北省中南部地区小麦冠腐病菌的分离频率较高,东北部麦区分离频率较低;经形态及分子生物学鉴定,河北省小麦冠腐病的病原菌主要为假禾谷镰刀菌和禾谷镰刀菌。

Occurrence and pathogen composition of wheat crown rot in Hebei Province

Field symptom and occurrence of wheat crown rot were investigated at 124 sites of 65 counties in Hebei Province during 2013-2015. Wheat crown rot caused basal stem browning and scattered whiteheads in the field. Investigation results showed that wheat crown rot mainly occurred in the mid-south of Hebei Province and the disease incidence and severity had been increasing along years. Wheat crown rot occurred sporadically in 2013, but the whiteheads caused by crown rot commonly existed in the field in 2015. The disease even resulted in premature in large area with whitehead rate of 20%-50% in some severe infected fields. Pathogen isolation results showed that isolation frequency of Fusarium species was high in the mid-south of Hebei Province, but low in the north-east of Hebei. Morphological and molecular identification showed that F.pseudograminearum and F.graminearum were the predominant pathogen causing wheat crown rot in Hebei