Rapid <i>In-Vitro</i>and <i>In-Vitro</i>Detection of <i>Chalara fraxinea</i>by Means of Mass Spectrometric Techniques

For the first time, mass spectrometric (MS) techniques were employed to rapidly detect the pathogen Chalara fraxinea in-vitro and directly in-vivo in tissues of diseased ash trees caused by C. fraxinea, using a range of characteristic novel secondary metabolites of C. fraxinea as chemical markers for the presence of the pathogen. We have found an evident correlation between the presence and amount of these-only for C. fraxinea characteristic and novel-secondary metabolites (named chalarafraxinines) and the degree of disease of respective infected ash seedlings. As demonstrated in this work, the MS based high-throughput-screening approach constitute an alternative to the time consuming and expensive micro biological isolation procedures for detection of the pathogen C. fraxinea and furthermore, can be used to rapidly test ash genotypes for resistance / susceptibility to C. fraxinea infection.

基于MaxEnt和DIVA-GIS的白蜡枯梢病菌在中国的潜在适生区分析

为了开展危险性林木病害白蜡枯梢病的风险分析和检疫工作,研究对白蜡枯梢病菌在中国的潜在适生区进行了预测。利用Max Ent软件和DIVA-GIS数据库,选择19个环境因子变量和2.5 min的空间分辨率,并对预测结果的可靠性进行ROC曲线法分析评价,同时采用Jackknife刀切法分析了各环境变量对预测结果的影响。结果表明:该病菌在我国局部地区有一定适生风险;根据得到的潜在适生区预测图,白蜡枯梢病菌在中国的高度适生区有台湾中部,中度适生区有西藏西南边陲林区、湖北神农架和宜昌三峡林区、湖南武陵山和张家界林区、广东、广西、重庆、贵州、江西、福建的局部等地;各环境因子贡献率分析表明最冷季降水量对白蜡枯梢病菌的适生区分布影响最大,研究预测结果AUC值为0.932,表明预测结果可信度高。

白蜡枯梢病及其在欧洲的发生情况

白蜡枯梢病是EPPO关注的检疫性病害,病原菌为Chalara fraxinea(有性型为Hymenoscyphuspseudoalbidus)。该病害于20世纪90年代初在欧洲波兰首次出现,2000年后在欧洲大陆迅速扩散,目前在欧洲大部分国家都已有发生报道。2012年该病在英国大面积暴发,更加引起关注。本文对白蜡枯梢病的病原菌分类地位、地理分布、寄主和危害、检测鉴定等进行综述,为防范该病害传入我国提供参考依据。