Chemical Control of Gray Blight of Tea in Korea

  • Shin, Gil-Ho (Tea Experiment Station, Chonnam Agriculture Research, Extension Service) ;
  • Hur, Jae-Seoun (Department of Environmental Education, Sunchon National University) ;
  • Koh, Young-Jin (Department of Applied Biology, Sunchon National University)
  • Published : 2000.06.01

Abstract

Screening of effective fungicides, determination of effective fungicide application time and investigation of the emergence of resistant isolates to fungicides were conducted to establish effective chemical control strategy of gray blight of tea (Camellia sinensis) in Korea. Systemic fungicides, such as bitertanol, were effective for controlling gray blight when the fungicides were sprayed within 3 days after cutting tea leaves for harvest. Sprayed immediately after cutting, contact fungicides such as chlorothalonil were also effective, but control efficacy rapidly decreased with lengthening of the intervals between cutting and spraying. Korean isolates of P. longiseta and P. theae were still sensitive to bitertanol or fluazinam. However, the isolates highly insensitive to copper hydroxide or thiophanate-methyl have already emerged in Korea. Therefore, careful attention should be paid to use of fungicides and spraying programs for the effective control of gray blight of tea in Korea.

Keywords