Study On Sensitivity Of Sagittaria Trifolia Linn.in Hei Longjiang Province To Sulfonylurea Herbicides

Sagittaria trifolia Linn,an perennial weed,was classified as Alismataceae Sagittaria. In recent years,the increasingdamage made it a serious weed species in rice fields in Heilongjiang Province. Sulfonylurea herbicides has been usedover the years to control Sagittaria trifolia. However, its controlling effect has decreased significantly due to the long-term use. In this paper, collected Sagittaria trifolia from Jiu Wang Village, Jiu Sheng Town, Qing’an County; ChangFu Village, Zhi Guang County, Wuchang City; the first team of Xing Kaihu Farm; Modern agricultural research anddevelopment center of854Farm; Jiang bin Farm; Wu Jimi Village, Shang Zhi City; Man Jianghong Village, Tie LiCounty, outdoor pot test was adopted to study the sensitivity to sulfonylurea herbicides.Furthermore, at thephysiological and biochemical leve ls, studied the effect of sulfonylurea herbicides on target enzyme acetolactatesynthas, to explored the mechanism of different sensitivity to sulfonylurea herbicides, provided a theoretical basis forcontrolling Sagittaria trifolia effectively and application of sulfonylurea herbicides.1.The sensitivity of the five groups to pyrazosulfuron-ethyl was significantly different, population H1was mostsensitive, the ED50was107.04g a.i./hm2,the IC50was27.21nm/L; followed by was population H2, H3, H4, the ED50was163.92,289.61,320.50g a.i./hm2, the IC50was73.82,129.95,1646.11nm/L;the most insensitive was populationH5, the ED50was484.06g a.i./hm2, the IC50was4226.23nm/L.After the treatment by pyrazosulfuron-ethyl, the ALSactivity of population H1was obviously inhibited, significantly larger than the other four populations, the inhibition ofpopulation H5was smallest,which was the main reason for the different sensitivity to Pyrazosulfuron-ethyl.2.The sensitivity of the five groups to bensulfuron methyl was different, population H2was most sensitive, theED50was673.55g a.i./hm2,the IC50was82.89nm/L;followed by was population H3,H1, the ED50was677.50,734.73g a.i./hm2, the IC50was677.50,734.73nm/L;the most insensitive was population H4, H5, both of the maximumfresh weight inhibition rate were less than50%, the ED50can not be determined, the IC50was2645.62,12721.35nm/L.After the treatment by bensulfuron methyl, the ALS activity of population H2was obviously inhibited, significantlylarger than the other four populations, the inhibition of population H5was smallest,which was the main reason for thedifferent sensitivity to bensulfuron methyl.In this thesis, studied the level of sensitivity difference of the main malignant weeds Sagittaria trifolia in rice fields in Heilongjiang Province to Sulfonylurea herbicides for the first time,cleared the mechanism of the difference insensitivity in Physiological and biochemical level.