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Chinese Journal of Biological Control ›› 2024, Vol. 40 ›› Issue (3): 710-716.DOI: 10.16409/j.cnki.2095-039x.2024.02.021

• RESEARCH REPORTS • Previous Articles    

Control Effect of Streptomyces roseoflavus and Fungicides on Phytophthora nicotianae

HAN Ruihua1, JIANG Kai2, KANG Yebin1   

  1. 1. College of Horticulture and Plant Conservation, Henan University of Science and Technology, Luoyang 471023, China;
    2. Luoyang Branch of Henan Provincial Tobacco Company, Luoyang 471023, China
  • Received:2023-10-21 Published:2024-06-07
  • Contact: 中国烟草总公司河南省公司重点科技项目(2023410000240022);中国烟草总公司重大科技项目[110202101051(LS-11)
  • Supported by:
    10.16409/j.cnki.2095-039x.2024.02.021

Abstract: This study aims to improve control effect ofStreptomyces roseoflavus LN33 on tobacco black shank by screening out fungicides and ratio combined with LN33. Toxicity of 3 kinds of fungicides and LN33 on Phytophthora nicotianane was determined with inhibition zone method and EC50values were calculated. Plate culture count method was used to determine the biocompatibility of fungicides and LN33, and the mixture scheme was determined with Horsfall method. The results showed that the EC50 values of metalaxyl and dimethomorph against P. nicotiananewere 0.26 and 0.92 μg/mL, respectively, while the EC50 value of metalaxyl was the lowest, which was only 0.26 μg/mL, and metalaxyl showed good biocompatibility with LN33. The IR value was 1.032 when volume ratio was 6:4 of 0.26 μg/mL metalaxyl and 3.41×107cfu/mL LN33. The growth inhibition rate and control efficacy of compounds on P. nicotianae in pot experiment were 86.96% and 77.06%, respectively,significantly higher that single dose. Therefore, metalaxyl can combine with S. roseoflavusLN33 to control P. nicotianae wilt, and only half amount of fungicide would be applied in the compound.

Key words: Streptomyces roseoflavus, fungicide, Phytophthora nicotianae, toxicity test, pot experiment

CLC Number: