河南省多花黑麦草对ACCase和ALS抑制剂的抗性及其靶标基因突变分析

为明确河南省部分地区的多花黑麦草Lolium multiflorum种群对乙酰辅酶A羧化酶（acetylCoA carboxylase,ACCase）和乙酰乳酸合成酶（acetolactate synthase,ALS）抑制剂类除草剂的抗性水平和抗性机理，采用整株生物测定法测定采自新乡市和驻马店市的多花黑麦草种群对ACCase抑制剂类除草剂精噁唑禾草灵、炔草酯、唑啉草酯和ALS抑制剂类除草剂甲基二磺隆、氟唑磺隆、啶磺草胺的抗性水平，并对多花黑麦草ACCase和ALS靶标酶编码基因进行克隆及氨基酸序列比对，分析其靶标抗性机理。结果显示，与多花黑麦草敏感种群HNXX01相比，HNZMD04和HNXX05种群对6种除草剂均产生了抗性，HNZMD04种群对精噁唑禾草灵和啶磺草胺的相对抗性倍数分别为44.65和40.31，对炔草酯和氟唑磺隆的相对抗性倍数分别为11.91和11.93;HNXX05种群对精噁唑禾草灵和氟唑磺隆的相对抗性倍数分别为27.70和25.67。HNZMD04和HNXX05抗性种群的ACCase基因均发生了D2078G突变，2个种群的突变率分别为55%和70%;HNZMD04...

Resistance to ACCase and ALS inhibitors and its target site mutation in Italian ryegrass Lolium multiflorum from Henan Province

To clarify the resistance level to acetyl-CoA carboxylase(ACCase) and acetolactate synthase(ALS) inhibitor herbicides and target site resistance mechanism in Italian ryegrass Lolium multiflorum populations from some areas of Henan Province, the whole-plant bioassays were conducted to determine the resistance of HNXX01, HNZMD04, HNXX05 populations against ACCase inhibitor herbicides(fenoxaprop-P-ethyl, clodinafop-propargyl, and pinoxaden) and ALS inhibitor herbicides(mesosulfuron-methyl, flucarbazone-sodium, and pyroxsulam). The ACCase and ALS target enzyme genes were cloned from these populations, and compared with amino acid sequence to find resistance-related mutations and clarify the mechanism of target site resistance. The results of resistance level test showed that HNZMD04 and HNXX05 populations were resistant to all the six herbicides compared to susceptible population HNXX01. HNZMD04 population was resistant to fenoxaprop-P-ethyl and pyroxsulam,with a relative resistance factor of 44.65 and 40.31, respectively. The relative resistance factor of HNZMD04 to clodinafop-propargyl and flucarbazone-sodium were 11.91 and 11.93, respectively. The relative resistance factor of HNXX05 population to fenoxaprop-P-ethyl and flucarbazone-sodium were 27.70 and 25.67, respectively. The results showed that the ACCase gene had a D2078G mutation in HNZMD04 and HNXX05 resistant populations, with a mutation rate of 55% and 70%, respectively. The ALS gene had P197Q and P197T mutations in HNZMD04 resistant population, with a mutation rate of 30% and 5%, respectively, while the ALS gene only had P197Q mutation in HNXX05 resistant population, with a the mutation rate of 15%. These results indicated that L. multiflorum populations from Zhumadian and Xinxiang developed high resistance to ACCase and ALS inhibitor herbicides. Furthermore,ACCase mutation at amino acid D2078G and ALS mutations at amino acids P197Q and P197T contributed the herbicide resistance in the L. multiflorum populations from Henan.