Investigation of Resistance to Penoxsulam and Cyhalofop-butyl in Echinochloa oryzicola Collected in Gyeongsangnam-do Province of Korea

Soo Yong  Shim1   Yong Hyun  Lee1   Jeongran  Lee2   Kee Woong  Park3,*   Jeung Joo  Lee4,*   

1Division of Applied Life Science (BK21 Plus), Gyeongsang National University, Jinju 52828, Korea
2Crop Protection Division, National Institute of Agricultural Sciences, RDA, Wanju 55365, Korea
3충남대학교 농업생명과학대학 식물자원학과
4Department of Plant Medicine, IALS, Gyeongsang National University, Jinju 52828, Korea

Abstract

In this study, Resistance of Echinochloa oryzicola biotypes collected in the rice fields of Gyeongnam province to both Cyhalofop-butyl and Penoxsulam were investigated by growth pouch assay. The collected biotypes showed a wide range of different sensitivities to both herbicides. For the standard known susceptible biotype, we used Sunchon biotype susceptible to Penoxsulam and Cyhalofop-butyl and determined as a Resistance if the GR50 value of a biotype is more than three times of the GR50 value of Sunchon biotype. Based on the GR50 values of 82 biotypes, 62.2% of biotypes were resistant to Penoxsulam, while 46.8% of biotypes were resistant to Cyhalofop-butyl. The Resistance/susceptible (R/S) GR50 ratio of the highest resistant biotype to Penoxsulam compared to the Sunchon biotype was 252.76 (Hamyang, HY-11 biotype), while that of the highest resistant biotype to Cyhalofop-butyl was 23.39 (Jinju, JJ-18 biotype).

Figures & Tables

Fig. 1.R/S ratio of resistant to susceptible in Gyeongnam province. GC: Geochang-gun; HC: Hapcheon-gun; CN: Changnyeong-gun; MY: Miryang-city; US: Ulsan-metropolitan-city; HY: Hamyang-gun; SNC: Sancheong-gun; UY: Uiryeong-gun; HA: Haman-gun; CW: Changwon-city; GH: Gimhae-city; YS: Yangsan-city; HD: Hadong-gun; JJ: Jinju-city; BS: Busan-metropolitancity; SC: Sacheongun; GS: Goseong-gun; NH: Namhae-gun; TY: Tongyeong-city; GJ: Geoje-city. The regions on the X axis correspond to the respective regions corresponding to the R/S ratio of Table 1.