亚洲玉米螟和桃蛀螟危害对玉米产量损失的影响

Study on Maize Yield Loss by Ostrinia furnacalis (Guenée) and Dichocrocis punctiferalis (Guenée) Damage

为明确玉米产量损失和害虫危害的关系,田间条件下采用剖秆法研究了亚洲玉米螟和桃蛀螟危害对玉米产量损失的影响。结果表明,亚洲玉米螟、桃蛀螟、虫孔在玉米植株各部分呈现不均匀分布,从垂直分布来看,穗下节上亚洲玉米螟数量最多,雌穗上桃蛀螟数量和虫孔数最多,雄穗上三者均最少;从水平分布看,穗上节、雌穗节、穗下节上亚洲玉米螟数量显著多于桃蛀螟,而雌穗上桃蛀螟显著多于亚洲玉米螟。整株玉米上虫孔数与亚洲玉米螟、桃蛀螟数量均呈显著正相关,秃尖长与穗上节桃蛀螟数量呈正相关,而穗重与整株虫孔数和雌穗虫孔数均呈显著负相关,穗粗与穗下节桃蛀螟数量呈负相关。因此,建议把整株或者雌穗虫孔数作为衡量玉米产量损失的主要指标。

To analysis the relationships between yield loss of maize and insect pest damage, the whole plant of maize were cut to study the maize yield loss caused by Ostrinia furnacalis(Guenée) and Dichocrocis punctiferalis(Guenée). The results showed that O. furnacalis, D. punctiferalis and worm holes had uneven distribution on maize plants. From vertical distribution, the most of O. furnacalis occured on the section below maize ear, the most of D. punctiferalis and worm holes occured on the female ear, and the least of O. furnacalis, D. punctiferalis and worm holes occured on male ear. From horizontal distribution, the number of O. furnacalis was more than D. punctiferalis on the section above ear, female ear section and section below ear, while the number of D. punctiferalis was more than O. furnacalis on female ear. There were significantly positive correlation between the number of worm holes and that of O. furnacalis and D. punctiferalis of the whole plant, and there were positive correlation between bare tip length and the number of D. punctiferalis on the section above ear. There were significantly negative correlation between the weight of maize ear and the worm hole numbers of the whole plant and female ear. The thick of maize ear was also negatively correlated with the number of D. punctiferalis on the section below maize ear. In conclusion, it was suggested that the number of worm holes of the whole plant or female ear should be used as the main indexes for assessing the maize yield loss.