内吸杀菌剂拌种双防治小麦散黑穗病的应用研究

研究结果表明,用40％拌种双可湿性粉剂按种子重量的0.2％拌种防治小麦散黑穗病,田间平均防效可稳定在85％以上,明显优于50％多菌灵可湿性粉剂0.2％及0.3％用量的效果。用该剂量,在发病率为1％的病区,即可收到经济效益。发病率愈高,经济收益愈显著。当发病率5％以上时,投资收益比为1:15左右。使用拌种双,只要保证拌种质量,不论干拌还是湿拌防病效果差异不大。但干拌较湿拌安全,且操作方便,易于推广。拌种双处理种子,春麦较冬麦安全,冬麦中不同品种耐药力又有所不同。用种子量的0.2％剂量拌种,对小麦发芽、出苗、营养生长及繁殖生长均无不良影响。用量至0.3％时,推迟春麦出苗1～2天,对冬麦发芽、出苗及早期生长均有不同程度的抑制作用。若使用湿拌特别是湿拌加闷种其影响更加明显。

INVESTIGATION ON THE CONTROL OF USTILAGO TRITICI ROSTRUP WITH A NEW SYSTEMIC FUNGICIDE BANZHONGSHOUANG

The result of many tests and experiments shows that the average control effect against loose smut of wheat was steady at 85% or over in the field,by dressing the wheat seeds with 40% Benzhongshouang W. P.at a rate of 0.2%.40% Banzhongshouang W.P. also shows better results than 50% Carbamate W.P.with the rate of 0.2% and 0.3% at seeds. If Banzhongshouang of this dose is applied in the district with 1%incidence of loose smut,it will achieve good economic result.The higherthe incidence of the disease,the more the benefit.At the incidence of 5% or over,the ratio of expense to benefit would be approximately 1:15. During the application of Banzhongshouang,attention should bepaid to the quality of the dressing work.For dry dressing or wet dressing of the seed,the control effect is quite similar.But dry dressing ismore safe in operation,simpler in handling,and easier to extend itsapplication. It is safer to treat spring wheat than winter wheat with Banzhongshouang.And for winter wheat,the effect of nzhongshouang is also different on various breeds of wheat seed. Dressing the wheat seed with a rate of 0.2% as mentioned in this paper,there are no harmful effects on the germination,emerging and growing of wheat.If the rate of 0.3% is used,the period for emergence of the seeds will be delayed one or two days,and there will be a certain degree of effect on germination,emergence,and the early stage of groing on the winter wheat. The effect of control of the disease will be more obvious if wetdressing method is used,especially with dipping,and keeping the seedin a container.