The biological characteristics of pathogens cowpea wilt disease in Sanya,Hainan,and the screening of effective fungicides
YI Jianfeng
XU Peidong
CHEN Di
ZHAO Tingchang
YI Kexian
LIN An
XIE Bingyan
ZHAO Wenjun
Abstract：To clarify the pathogen species and biological characteristics of cowpea wilt disease in Sanya,Hainan province,and screen out suitable agents for its prevention and control,three representative pathogen strains were separated from diseased cowpea plant roots and stems.The pathogenicity was determined using the Koch-style rule,and the strains were identified through morphological features and genetic analysis of ITS,TEF-1α,and TUB gene sequences.The biological characteristics of pathogenic bacteria and the sensitivity determination of common fungicides were analyzed by mycelial growth rate assay.The pathogen was identified as Fusarium oxysporum f.sp.tracheiphilum based on combined results of the pathogenicity test(the pathogen only infects cowpea)and molecular identification.Biological tests revealed that the optimal conditions for the vegetative growth of strains were lactose and maltose as carbon sources,potassium nitrate and sodium nitrate as nitrogen sources,at temperature of 20-30℃,pH 7.0-10.0,and in complete darkness.The strains grew fastest on CDA medium,with a lethal temperature of 65-70℃.Furthermore,the inhibitory effects of ten agents,among which fungicide-prochloraz had the best antifungal activity,with EC50 values of 0.034 4 μg·mL-1.This study provides scien-tific evidence and theoretical guidance for diagnosing and effectively controlling cowpea wilt in Sanya,Hainan.
Keywords：CowpeaCowpea wilt diseasesFusarium oxysporum f.sp.tracheiphilumBiological identificationFungi-cide screening
Publication Date：2025-05-05
Online Publishing Date：2025-08-15(First online date of this platform, not the publication date of the document)
Pages：12( 37-48 )