谷子和杂草对氰氟草酯的敏感性

通过室内生物测定试验和田间小区试验,明确氰氟草酯对谷子的安全性和杂草的敏感性,为氰氟草酯在谷田的应用提供理论依据。室内生物测定试验结果表明,谷田恶性杂草牛筋草和谷莠子对氰氟草酯分别为高度敏感（GR₉₀ 45.02g a.i./hm²）和一般敏感（GR₉₀ 124.13g a.i./hm²）。氰氟草酯对冀谷39和杂草的选择性指数大于2,且为不敏感（GR₁₀ 284.05g a.i./hm²）,对豫谷18和杂草的选择性指数小于1,且为高度敏感（GR₁₀ 13.70g a.i./hm²）。冀谷39的抗药性指数为9.65。田间试验结果进一步表明,氰氟草酯能有效防除抗除草剂谷子品种冀谷39田间的禾本科杂草,对牛筋草和马唐的防效高,氰氟草酯在110g a.i./hm²剂量下对牛筋草和马唐的鲜重防效和株数防效均高于96%;氰氟草酯对谷莠子生长有显著抑制作用,110g a.i./hm²剂量对谷莠子的鲜重防效大于80%,对冀谷39的株高和鲜重没有影响。结果揭示了抗除草剂谷子品种冀谷39对氰氟草酯有较强的耐药性,普通谷子品种豫谷18对氰氟草酯没有耐药性,合理使用氰氟草酯能够有效防除冀谷39田间的多种禾本科杂草。

Sensitivity of Foxtail Millets (Setaria italica L.) and Weeds to Cyhalofop-Butyl

Bioassay experiment and field plot test were executed to examine the weed sensitivity of cyhalofop-butyl and its safety on foxtail millet for providing theoretical guidance for the application of cyhalofop-butyl in millet field. The results of the laboratory bioassay test showed that Eleusine indica L. was highly sensitive (GR₉₀=45.02g a.i./ha) to cyhalofop-butyl and Setaria faberii Herrm. was commonly sensitive (GR₉₀=124.13g a.i./ha) to it. The selection index of cyhalofop-butyl between Jigu 39 and weeds was higher than 2 and Jigu 39 showed low sensitivity (GR₁₀=284.05g a.i./ha) to cyhalofop-butyl. The selection index of Yugu 18 was below 1 and Yugu 18 showed highly sensitive (GR₁₀=13.70g a.i./ha) to it. The resistant index of Jigu 39 was 9.65. Field test results further showed that cyhalofop-butyl could effectively control grassy weeds in the herbicide-resistant millet field. It had high control effect to E. indica and Digitaria sanguinalis L., both of biomass and number control effect were higher than 96% at the dose of 110g a.i./ha. It also had a significant inhibitory effect on S. faberii and the biomass control effect was higher than 80%. Biomass and plant height of Jigu 39 were unaffected by cyclofop-butyl. According to the study, Yugu 18 shown great susceptibility to cyhalofop-butyl while Jigu 39, a herbicide-resistant millet type, was resistant to it. In a field of herbicide-resistant millet, using cyhalofop-butyl wisely could successfully suppress grass weeds.