Journal of Integrative Agriculture ›› 2011, Vol. 10 ›› Issue (7): 1049-1055.DOI: 10.1016/S1671-2927(11)60093-X

• 论文 • 上一篇    下一篇

Occurrence of Glyphosate-Resistant Horseweed (Conyza canadensis) Population in China

  

  1. Weed Research Laboratory, Nanjing Agricultural University
  • 收稿日期:2010-07-27 出版日期:2011-07-21 发布日期:2011-08-14
  • 通讯作者: Correspondence QIANG Sheng, Professor, Tel: +86-25-84395117, E-mail: qiangs@njau.edu.cn, wrl@njau.edu.cn
  • 作者简介:SONG Xiao-ling, Ph D, E-mail: sxl@njau.edu.cn;

Occurrence of Glyphosate-Resistant Horseweed (Conyza canadensis) Population in China

  1. Weed Research Laboratory, Nanjing Agricultural University
  • Received:2010-07-27 Online:2011-07-21 Published:2011-08-14
  • Contact: Correspondence QIANG Sheng, Professor, Tel: +86-25-84395117, E-mail: qiangs@njau.edu.cn, wrl@njau.edu.cn
  • About author:SONG Xiao-ling, Ph D, E-mail: sxl@njau.edu.cn;

PDF

摘要： Horseweed (Conyza canadensis), an invasive alien weed, is one of the main weeds in orchards in China. Althoughglyphosate has been used for control of horseweed and many other weeds in orchards for more than 25 years in China, acase of glyphosate-resistant horseweed has not been identified in orchard in China so far despite glyphosate-resistanthorseweed cases have been reported in some other countries. Seeds of 25 horseweed populations were collected fromdifferent orchards with different glyphosate application history. Potted seedlings with 11-13-leaf growth stage weretreated with glyphosate at 0.035, 0.07, 0.14, 0.28, 0.56, 1.12, 2.24, 4.48, and 8.96 kg a.i. ha-1. The dosage dependenceresponse curve of each population was constructed with Log-logistic dose response regression equations. The ED50value of each population was calculated and compared with the susceptible population from China. Different populationshad different relative glyphosate-resistant levels which increased with the number of years of glyphosate application.Two populations with the highest resistance levels, 8.28 and 7.95 times, were found in Ningbo, Zhejiang Province, China,where glyphosate was used for weed control in orchards twice each year for 15 yr. The two resistant populationsaccumulated approximately two to four times less shikimic acid than the two susceptible populations 48 h after glyphosateapplication.

关键词:

Abstract: Horseweed (Conyza canadensis), an invasive alien weed, is one of the main weeds in orchards in China. Althoughglyphosate has been used for control of horseweed and many other weeds in orchards for more than 25 years in China, acase of glyphosate-resistant horseweed has not been identified in orchard in China so far despite glyphosate-resistanthorseweed cases have been reported in some other countries. Seeds of 25 horseweed populations were collected fromdifferent orchards with different glyphosate application history. Potted seedlings with 11-13-leaf growth stage weretreated with glyphosate at 0.035, 0.07, 0.14, 0.28, 0.56, 1.12, 2.24, 4.48, and 8.96 kg a.i. ha-1. The dosage dependenceresponse curve of each population was constructed with Log-logistic dose response regression equations. The ED50value of each population was calculated and compared with the susceptible population from China. Different populationshad different relative glyphosate-resistant levels which increased with the number of years of glyphosate application.Two populations with the highest resistance levels, 8.28 and 7.95 times, were found in Ningbo, Zhejiang Province, China,where glyphosate was used for weed control in orchards twice each year for 15 yr. The two resistant populationsaccumulated approximately two to four times less shikimic acid than the two susceptible populations 48 h after glyphosateapplication.

Key words: horseweed [Conyza canadensis (L.) Cronq.], glyphosate, resistance, shikimic acid