久效磷在悬铃木体内转运残留动态及防害效果研究

STEM INJECTION AND RING PAINTING OF MONOCROTOPHOS ON THE RESIDUE LEVEL AND INSECTS CONTROL IN PLANE TREE

将久效磷农药（４０％乳油作１∶１稀释）以低污染施药术对悬铃木植株定量茎部注射（２０ｍｌ／株）和茎部环涂（５０ｍｌ／株），每隔３～４ｄ，采集树冠层枝叶样品，用气相色谱法测定久效磷的残留量。结果表明，久效磷在树冠层枝叶中的水平在茎部环涂树约需１５ｄ才能达到最高，而在茎部注射树只需６ｄ就达到高峰，对供试树进行长期药效观察显示，２种施药方法处理的树木在施药后１５ｄ不见虫害直到第２年仍无虫害发生；而附近未进行施药处理的悬铃木都受到虫害。此外，在施药前后对施药树木的根部土壤和周围大气取样作气相色谱分析，农药残留量都低于仪器检测限（＜０．０１ｍｇ／ｋｇ），这说明茎部注射和茎部环涂都是安全可靠的低污染施药方法。

The monocrotophos, 40% EC 1∶1 diluted in water, was injected into plane tree stem at the does of 20ml/tree and ring painted around the stem at 50ml/tree. The branches and leaves on the tree crown were colected thereafter at 3￣4 days intervals in one month as gas chromatography analytical samples. The results showed that the monocrotophos level in the crown branches and leaves reaches highest in 15 days in the tree of ring painting treatment, while only 6 days in the trees of injection treatment. The insect control effect observed until next year that no insects appeared on the trees of both treatment, but the trees nearby without any trestment were affected by insects. The gas around tree and the soil 20cm deep close the tree were also sampled before and after the insecides application and analysed by gas chromatoraphy, the level of monocrotophos in these sample was out of the detecting limit in the gas chromatography (<0.01mg/kg), which showed both treatment of monocrotophos were safety.