嘧霉胺对采后柑橘绿霉病的防治效果

在实验室和贮藏库条件下,对嘧霉胺单剂、嘧霉胺与抑霉唑或嘧霉胺和咪鲜胺混剂防治柑橘绿霉病的效果进行了评价。室内实验结果表明:采用500或1 000 mg/L嘧霉胺单剂、500 mg/L嘧霉胺+500 mg/L抑霉唑或500 mg/L嘧霉胺+500 mg/L咪鲜胺混剂在接种后12~18 h进行浸果处理,对由抑霉唑抗性或敏感菌株引起的绿霉病均有显著的防治效果,防效超过94%;500或1 000 mg/L 的抑霉唑对敏感菌株的防效在93%以上,但对抗性菌株的防效低于70%。贮藏库防效试验结果表明:在具抑霉唑抗性菌系的贮藏库中,上述质量浓度的嘧霉胺单剂、嘧霉胺与抑霉唑、或嘧霉胺与咪鲜胺混剂对绿霉病的防治效果明显优于抑霉唑单剂;而在不具抗抑霉唑菌系贮藏库中的防效则与抑霉唑相当。由此认为:嘧霉胺可作为抑霉唑的替代药剂应用于柑橘的采后处理,其推荐使用质量浓度为500~1 000 mg/L,可单独使用,也可与抑霉唑或咪鲜胺混合使用。

Efficacy of pyrimethanil in controlling green mouldof postharvest citrus

The efficacy of pyrimethanil alone,pyrimethanil-imazalil or pyrimethanil-prochloraz mixtures were evaluated in controlling the green mould of postharvest citrus both under the conditions of laboratory and farmers storage houses.In laboratory,aqueous fungicide solutions were applied by soaking citrus 12 to 18 h after inoculation.Pyrimethanil alone (at 500 or 1 000 mg/L),pyrimethanil-imazalil or pyrimethanil-prochloraz mixtures (at 500+500 mg/L) showed higher than 94% efficacy in controlling green mold regardless of the inoculation with imazalil-resistant or imazalil-sensitive isolates;whereas,imazalil alone (at 500 or 1 000 mg/L) was poorly effective in controlling imazalil-resistant isolate.In practical application experiments in three-farmer storages done in 2007 and 2008,pyrimethanil alone,pyrimethanil-imazalil or pyrimethanil-prochloraz mixtures at above concentrations performed higher efficacy than imazalil alone at same concentrations in the storage house where the imazalil-resistant isolate had been detected,but at similar controlling level in storage where the imazalil-resistant isolate had never been detected.In conclusion,pyrimethanil could be used to replace imazalil for controlling citrus green mould.It could be used as a single solution or mixtures of pyrimethanil-imazalil or pyrimethanil-prochloraz,at concentration of above 500 mg/L.