河北省桃树叶部黑斑病病害发生调查及其拮抗生防菌MCTR-5的鉴定

Survey on the occurrence of peach leaf black spot disease and identification of its antagonistic bacterium MCTR-5 in Hebei Province

黑斑病是河北省桃树的主要病害之一,影响桃的产量和品质。为了解桃树叶部黑斑病发生情况,本研究系统调查了河北省桃主产区桃树叶部黑斑病的发生情况,发现桃树叶部黑斑病普遍发病率在30%以上,发病严重的桃园病叶率达50%以上。定点调查发现,桃树叶部黑斑病的发生与叶片部位和桃品种具有相关性。为了筛选桃树叶部黑斑病的拮抗生防菌,采集了桃树根际土样及健康桃叶,筛选纯化获得60株不同形态的拮抗生防菌,其中7株菌株对桃叶部黑斑病致病菌链格孢菌具有抑菌效果。菌株MCTR-5和SPTR-10抑菌效果最好,抑菌率分别为79.83%和82.05%。经形态学观察、生理生化特性及系统发育树分析,明确拮抗生防菌株MCTR-5为甲基营养芽孢杆菌(Bacillus methylotrophicus)。本研究探明了河北省桃树叶部黑斑病的发生严重程度及规律,筛选到对河北省桃树叶部黑斑病致病病原菌链格孢菌具有拮抗作用的生防菌株,为防治桃树叶部黑斑病提供了理论依据。

Black spot is one of the major diseases of peach trees in Hebei Province,affecting the yield and quality of peach.In order to understand the occurrence of peach leaf black spot disease,this study systematically investigated the occurrence of peach leaf black spot disease in the main peach production areas in Hebei Province.It was found that the incidence of peach leaf black spot was generally above 30%,and the incidence of the disease in serious peach orchards was above 50%.The fixed-point survey showed that the occurrence of peach leaf black spot was related to the position of leaves and peach varieties.In order to screen for the antagonistic bacteria,60 strains of antagonistic bacteria were collected from peach soil samples and healthy peach leaves,and seven of them were found to be effective against Alternaria altemata.MCTR-5 and SPTR-10 were the most effective strains with 79.83%and 82.05%inhibition rate respectively.Morphological observations,physiological and biochemical characteristics and phylogenetic analysis showed that the antagonist strain MCTR-5 was Bacillus methylotrophicus.Taken together,this study investigated the severity and pattern of leaf black spot of peach trees in Hebei Province,and found an antagonistic bacteria to the causal agent of leaf black spot of peach trees in Hebei Province,providing a theoretical basis for the control of leaf black spot of peach trees.