几种保苗剂防治棉蚜效果及其对棉花出苗保苗综合效应的研究

在防治棉蚜的田间小区试验中，保苗剂９号和１号处理棉种（药剂∶种子＝１∶５０，下同）防治效果最好，维持８９．１％以上的防效达３０ｄ；其次为保苗剂８号，３０ｄ平均防效为７７．９％；保苗剂２号对棉蚜无效。４种保苗剂处理棉种对棉花安全，其出苗率和保苗效果均显著高于对照。温室外试验结果表明：不同温度和湿度对包衣棉种出苗率和保苗效果的影响很大。不同温度条件下，土壤湿度在１９．８４％～１９．９６％时的出苗率远远低于对照；平均温度为１３．３℃，土壤湿度为２７．５６％时，经种衣剂２４号处理的棉种的出苗率、保苗效果最好；土壤湿度为２４．６５％时，保苗剂９号处理的出苗率保苗效果较好。平均温度为２１．２℃，土壤湿度为２２．７５％时，种衣剂２４号和保苗剂９号处理的出苗率较高，保苗效果是对照的１．０６～１．１６倍。另外，还采用了新的统计方法来评价持效期较长的保苗剂的防虫效果

The Control Efficiency with Several Kinds of Protecting Agent of Seedling for Cotton Aphis and the Effect on Cotton Emergence and Retaining

The control efficiency with several kinds of Protecting Agent of Seedling (PAS) for cotton aphis(Aphis gossypii Glover) were conducted in field control trials.The dosage of PAS was 1/50 cotton seed.The best result of control the aphis was gained by using PAS 9 and PAS 1,above 89.1% control result were kept for 30 days.The average effect of PAS 8 after sowing for 30 days was about 77.9%.PAS 2 was not effective. A quite satisfied effect of four kinds of PAS for cotton seedling growth was gained from field trials. Preliminary test for applying the PAS treated cotton seeds with two tempretures and three soil humidies in the outside glasshouse.The method of evaluating the control efficiency as well as expression of the index of crop protection are also given in this paper.