中文摘要：

为探明二代亚洲玉米螟发生量对玉米产量损失的影响,本试验在田间采用人工密度梯度接卵法（0、20、50、100和200块·百株-1）,模拟自然情况亚洲玉米螟发生量,研究辽宁地区二代亚洲玉米螟（Ostrinia furnacalis Guenée）对玉米的经济阈值。结果表明：百株接卵量与虫孔数呈极显著正相关（P〈0.01）,百株虫孔数与产量损失率呈极显著正相关（P〈0.01）,回归方程分别为y=3.1999x＋24.8416（R2=0.953,P〈0.01）,y=0.0234x-1.6167（R2=0.988,P〈0.01）,推导出百株接卵量与玉米产量损失率的方程为z=0.0749x-1.0354,即落卵量每增加1块,虫孔数增加约3.2个,产量损失率增加7.49%;隧道长度与雌穗长度、穗粗及粒重呈极显著负相关（P〈0.01）,与产量损失率呈极显著正相关（P〈0.01）,表明玉米茎秆隧道长度每增加10 cm,玉米平均减产7.02 g,产量损失率平均增加4.38%;根据经济阈值定义,在产量8411 kg·hm-2的玉米田,使用松毛虫赤眼蜂（Trichogramma dendrolimi Matsumura）进行单次防治时,辽宁地区防治二代亚洲玉米螟的经济阈值为百株玉米累计落卵量17.39块。

英文摘要：

To determine the influence of second-generation Asian corn borer（ Ostrinia furnacalis）（ Guenée） on corn yield,we simulated the damage caused by Asian corn borer under natural conditions,to study the economic threshold of the second-generation Asian corn borer in Liaoning. Field tests were conducted to infest the spring corn LD565 with a series of egg mass numbers（ 0,20,50,100 and 200 egg-masses per 100 plants）. Correlation analysis revealed that egg mass number per 100 plants showed a significant positive correlation with stalk hole number per100 plants（ P〈0.01）,with a regression equation y = 3.1999x＋24.8416（ R2= 0.953,P〈0.01）;stalk hole numbers per 100 plants showed a significant positive correlation with yield loss rate（ P〈0.01）,with a regression equation y = 0.0234x-1.6167（ R2= 0.988,P〈0.01）. The correlation between the number of egg-masses per 100 plants and corn yield loss rate met the equation z = 0.0749x-1.0354,meaning that stalk holes would increase by 3.2 and maize yield loss would increase by 7.49% with per one increase in egg mass number. Tunnel length showed a negative correlation with ear length,ear diameter and yield weight per plant（ P〈0.01）,while a positive correlation with yield loss rate（ P〈0.01）. Maize yield loss would increase by 4.38% with per 10 cm increase in tunnel length. In conclusion,the economic threshold of applying Trichogramma dendrolimi Matsumura to control Asian corn borer would be 17.39 egg-masses per 100 plants in the field with a grain yield of 8411 kg·hm-2.