北京地区褐足角胸肖叶甲发生规律的初步研究

Preliminary study on the occurrence of Basilepta fulvipes in Beijing

通过普查、系统调查、室内饲养和田间笼罩观察等方法,对褐足角胸肖叶甲在北京地区的发生为害规律开展了研究。结果表明,褐足角胸肖叶甲在全市均有分布,北部山区的虫口密度显著低于南部潮土区。在春夏玉米交错分布区,未发现褐足角胸肖叶甲取食春玉米。北京地区有红棕型和铜绿鞘型2种色型,其中红棕型占93.32%,为绝对优势色型。普查中发现该虫可取食多种植物,其中马齿苋、野艾蒿、茵陈蒿等3种杂草是寄主植物新记录。系统调查表明,北京1年仅见1代成虫,7中下旬是该虫在北京为害的关键期。调查分析显示北京地区褐足角胸肖叶甲在夏玉米田符合聚集分布特征。行为观察发现褐足角胸肖叶甲为害玉米时,喜欢从正面啃食。室内饲养和田间笼罩观察发现成虫平均寿命约为20d。通过调查,首次证实在北京地区,褐足角胸肖叶甲以幼虫在玉米根部5～10cm土层中越冬。本研究初步明确了褐足角胸肖叶甲在北京地区的发生规律,可促进相关预测预报技术的提升,为综合防控提供决策依据。

The occurrence regularity of Basilepta fulvipes in Beijing was investigated by general and systematic surveys,indoor rearing,field cage with nylon mesh.The results showed that B.fulvipes distributed in every suburb districts,but the population density in the north area of cinnamon soils was significantly lower than that in the south districts of fluvo-aquic soils.Among the mixed area where spring maize was planted close to summer maize fields,no damage was found on spring maize.In Beijing,all B.fulvipes adults could be divided into 2 types,one is of red-brown color,and the other is of patina color.The former color type was the dominant type,accounting for 93.32%.In fields,B.fulvipes adults could feed on not only the reported plants,but also three weed plants,including Portulaca oleracea,Artemisia lavandulaefolia and Artemisia capillaris,which are the new records of the host plants of the pest.Field surveys indicated that only one generation of B.fulvipes adults appeared in 2014 in Beijing,and generation peak time was in late July,which was the critical period of the damages of B.fulvipesadults.Distribution pattern of B.fulvipes adults in summer maize fields accorded with the characteristics of aggregated distribution.B.fulvipes adults preferred to gnaw on the front of the corn leaves.The indoor rearing and field cage test showed that the average longevity was about 20 d.It was the first report that B.fulvipes larvae overwintered in the soil with the depth of 5 to10 cm in Beijing.The above results are not only helpful for the improvement of forecasting techniques,but also provide a decision basis for the pest integrated managements.