Rice Science ›› 2019, Vol. 26 ›› Issue (5): 300-308.DOI: 10.1016/j.rsci.2019.08.004

• Research Papers • Previous Articles     Next Articles

Quinclorac Resistance in Echinochloa crus-galli from China

Qiong Peng1,2,3, Heping Han3, Xia Yang1,4, Lianyang Bai1,2, Qin Yu3(), B. Powles Stephen3   

  1. 1 Hunan Agricultural Biotechnology Research Institute, Hunan Academy of Agricultural Sciences, Changsha 410125, China
    2 Collaborative Innovation Center for Field Weeds Control, Hunan University of Humanities, Science and Technology, Loudi 417000, China
    3 Australian Herbicide Resistance Initiative, School of Agriculture and Environment, University of Western Australia, WA 6009, Australia
    4 Jiangsu Academy of Agricultural Sciences, Nanjing 210014, China
  • Received:2018-07-27 Accepted:2018-12-09 Online:2019-09-28 Published:2019-05-24

Abstract:

Echinochloa crus-galli is a major weed in rice fields in China, and quinclorac has been long used for its control. Over-reliance of quinclorac has resulted in quinclorac resistance in E. crus-galli. Two resistant (R) E. crus-galli populations from Hunan, China were confirmed to be at least 78-fold more resistant to quinclorac than the susceptible (S) population. No difference in foliar uptake of 14C-labelled quinclorac was detected between the R and S plants. However, a higher level of 14C translocation and a lower level of quinclorac metabolism were found in the R plants. Basal and induced expression levels of β-cyanoalanine synthase (β-CAS) gene and β-CAS activity were not significantly different between the R and S plants. However, the induction expression of 1-aminocyclopropane-1-carboxylic acid oxidase (ACO1) gene by quinclorac treatment was evident in the S plants but not in the R plants. Quinclorac resistance in the two resistant E. crus-galli populations was not likely to be related to foliar uptake, translocation or metabolism of quinclorac, nor to cyanide detoxification via β-CAS. Thus, target-site based quinclorac signal reception and transduction and regulation of the ethylene synthesis pathway should be the focus for further research.

Key words: Echinochloa crus-galli, quinclorac resistance, quinclorac metabolism, β-cyanoalanine synthase, 1-aminocyclopropane-1-carboxylic acid synthase, 1-aminocyclopropane-1-carboxylic acid oxidase, rice