假禾谷镰孢子囊壳的田间采集和子囊孢子后代室内杂交条件优化

假禾谷镰孢(Fusarium pseudograminearum,Fp)是我国黄淮麦区小麦茎基腐病(Fusarium crown rot of wheat)的优势病原菌,目前该病害呈不断蔓延和为害加重的趋势.本研究从五月中旬小麦灌浆期至玉米收获期,在河南开封和焦作田间调查采集小麦茎基腐病样,对13份小麦茎秆和小麦残茬上...

Optimum culture conditions in the lab for sexual stage formation of ascospore isolates from perithecia collected in field for Fusarium pseudograminearum

Fusarium pseudograminearum (Fp) is one of the main pathogens of wheat Fusarium crown rot (FCR) that has been spreading and aggravating in Huanghuai winter region. In this study, from the wheat grain filling period in mid-May to the harvest of maize in Kaifeng and Jiaozuo, Henan Province, we invested and collected the sick wheat plants and 13 stubbles with perithecia in the field. The single ascospore was isolated from ascus of perithecia. Based on morphological and molecular characteristics, a total of 327 single spore cultures were identified to be F. pseudograminearumin which 164 and 163 strains belonged to MAT-1 and MAT-2, respectively. To improve sexual stage formation in the laboratory, the mating experiment was carried out using the ascospore cultures with opposite mating type to obtain the optimum conditions started from that reported abroad. The result of mating experiment showed that using Sachs synthetic medium with rice stem node, alternate black and cold white light at 22 ℃ for about 60 days, the KF86×KF73 combination produced a large number of mature perithecia and ascospores. Collectively, we used the ascospore cultures to set up mating experiment in the laboratory and obtained the optimized conditions and high fertile strains which provide methods and material for future study on gene functions at the sexual reproduction stage.