甜菜立枯病病原菌的分离和鉴定

旨在明确黑龙江大学呼兰校区甜菜立枯病的病原菌种类，为科学防治该病提供理论参考。以采自黑龙江大学呼兰校区的甜菜立枯病植株为试材，用形态学观察、致病性测定和分子生物学鉴定方法，依据柯赫氏法则，对病原菌进行分离和鉴定。结果表明，从发病甜菜幼苗根部上分离出的菌株L1，菌丝呈白色。大型分生孢子为镰刀型，有隔膜，小型分生孢子多为单细胞少数有隔膜。分子鉴定结果显示，该病原菌在基于ITS和tef1序列构建的系统发育树上与腐皮镰孢菌类群处同一分支。根据形态学和分子鉴定结果，确定引起黑龙江大学呼兰校区甜菜立枯病的病原菌为腐皮镰孢菌(Fusarium solani)。

Pathogenic Bacteria of Sugar Beet Blight: Isolation and Identification

The study aims to identify the pathogenic bacterial species responsible for sugar beet blight on the Hulan campus of Heilongjiang University and provide theoretical reference for the scientific prevention and treatment of the disease. Sugar beet blight plants collected from the Hulan campus of Heilongjiang University were used as test materials, and the pathogens were isolated and characterized by morphological observation, pathogenicity determination, and molecular biology according to the Koch's law. The results showed that strain L1 isolated from the roots of pathogenesis sugar beet seedlings had white hyphae. Large conidia were of the sickle type and had septa, and small conidia were mostly single cell with a few septa. The molecular identification results showed that this pathogen was in the same clade at the Fusarium saprophyticus group on a phylogenetic tree constructed based on ITS and tef1 sequences. Based on the morphological and molecular characterization results, the pathogen responsible for causing sugar beet blight on the Hulan campus of Heilongjiang University was determined to be Fusarium solani.