黑龙江省部分稻田萤蔺种群对吡嘧磺隆的抗药性分析

An analysis on the resistance of some Scirpus juncoides Roxb. populations in rice fields from Heilongjiang Province to pyrazosulfuron-ethyl

【目的】明确黑龙江省部分稻田萤蔺(Scirpus juncoides Roxb.)对吡嘧磺隆的抗药性水平及抗性机制,为水稻田萤蔺的综合治理提供理论依据。【方法】以采自黑龙江省的23个萤蔺种群为试验材料,利用整株盆栽法测定其对吡嘧磺隆的抗药性水平。选取代表性抗性种群(SC-1和SC-8)和敏感种群(SC-23),于萤蔺抽茎期剪取花茎后,以不同浓度(0.1、10.0、100.0、1000.0和10000.0 nmol/L)的吡嘧磺隆溶液对其进行离体乙酰乳酸合成酶(ALS)检测;抽茎期喷施250 g/ha吡嘧磺隆对萤蔺进行茎叶处理,施药后第0、1、3、5、7和9 d剪取花茎,分别用于活体ALS活性和谷胱甘肽—硫—转移酶(GSTs)活性测定。【结果】整株盆栽法测定结果表明,供试22个种群中有7个种群对吡嘧磺隆产生了抗性,占供试种群的31.8%。离体条件下,抗性种群SC-1和SC-8体内ALS对吡嘧磺隆的敏感性明显降低,抗性指数分别为69.81和23.83;活体条件下,抗性种群SC-1和SC-8的ALS相对活性受到抑制后均能恢复至正常水平,敏感种群SC-23则不能恢复,3个种群试验结束时(第9 d)的相对活性别为0.92、0.72和0.45;抗性种群SC-1和SC-8的GSTs相对活性自施用吡嘧磺隆后第1 d起均显著高于敏感种群SC-23(P<0.05),且二者分别于施药后第3和第1 d升至最高值,分别为2.36和1.94,敏感种群SC-23的GSTs相对活性于施药后第1 d升至最高值,为1.49。【结论】黑龙江省部分地区稻田萤蔺已对吡嘧磺隆产生了低到中等水平抗性。抗性萤蔺种群的ALS对吡嘧磺隆敏感性下降和GSTs代谢作用增强可能与其抗性有关。

【Objective】Resistance level and resistance mechanism of some Scirpus juncoides Roxb.populations in rice fields from Heilongjiang Province to pyrazosulfuron-ethyl were studied to provide a theoretical basis for the comprehensive management of S.juncoides Roxb.in paddy field.【Method】Who-plant bioassays was used to detect the resistance of 23 S.juncoides Roxb.populations which were collected from Heilongjiang Province to pyrazosulfuron-ethyl.Representative resistant populations(SC-1,SC-8)and sensitive populations(SC-23)were selected as the test materials,stems were cut at the stooling stage followed by different concentrations of pyrazosulfuron-ethyl(0.1,10.0,100.0,1000.0,10000.0 nmol/L)solution for acetolactate synthetase(ALS)test in vitro.In order to determine the ALS activity in vivo and glutathione-sulfur-transferase(GSTs)activity,foliage treatment was applied with 250 g/ha pyrazosulfuron-ethyl at the stooling stage and the stems were cut at 0,1,3,5,7 and 9 d after the application,respectively.【Result】The who-plant bioassays results showed that there were seven populations out of twenty tested populations which were resistant to pyrazosulfuron-ethyl,accounted for 31.8% of the total tested populations.The sensitivity of ALS to pyrazosulfuron-ethyl were decreased in both resistant populations SC-1 and SC-8 in vitro with resistance indexes of 69.81 and 23.83,respectively.The relative enzymatic activity of ALS in both resistant populations(SC-1 and SC-8)could be recovered to normal after inhibition in vivo,while that of the sensitive population SC-23 could not recover,and at the end of the experiment(day 9),the values were 0.92,0.72 and 0.45,respectively.The relative activities of GSTs in resistant populations(SC-1 and SC-8)were significantly higher than the sensitive population(SC-23)from the first day after application of pyrazosulfuron-ethyl(P<0.05),and they rose to the highest values on day 3 and day 1 after application respectively,which were 2.36 and 1.94.The relative activity of GSTs in sensitive population SC-23 rose to the highest value on the first day after application,which was 1.49.【Conclusion】Partial S.juncoides Roxb.populations in rice fields from Heilongjiang Province has established low to medium resistance to pyrazosulfuron-ethyl.Decreased sensitivity of ALS of resistant S.juncoides Roxb.populations to pyrazosulfuron-ethyl and increased GSTs metabolism might be related to the resistance.