4种烟剂对空仓储粮害虫成虫的药效试验

针对目前用于防治储粮害虫的空仓杀虫剂杀虫效果差,施用操作麻烦,杀虫剂对操作人员身体危害大等问题,在空仓环境内,进行了残杀威、敌百虫、溴氰菊酯及高效氯氰菊酯4种烟剂对谷蠹、米象、赤拟谷盗、锈赤扁谷盗、锯谷盗和嗜卷书虱等6种储粮害虫成虫的防治效果测试。结果表明,2.5%溴氰菊酯烟剂杀虫效果最好,100%杀死试虫;2%高效氯氰菊酯烟剂杀虫效果次之,试虫死亡率在99.3%以上;20%残杀威的触杀效果较溴氰菊酯、高效氯氰菊酯差一些,赤拟谷盗试虫死亡率85%以上;30%敌百虫烟剂的触杀作用较差,谷蠹和锈赤扁谷盗试虫的死亡率在85%以上。     

2种农药防治甘蔗害虫的效果及对蔗茎产量的影响

在甘蔗分蘖期施放棵棵无损5%颗粒剂和呋喃丹3%颗粒剂,探讨这2种农药防治甘蔗害虫的效果及对蔗茎产量的影响。试验结果表明:对甘蔗螟虫的防效,棵棵无损和呋喃丹不相上下;对甘蔗蓟马、绵蚜虫的防效,棵棵无损明显好于呋喃丹。对蔗茎产量和经济效益的影响,棵棵无损比对照增产极显著,产量增长15.1%,效益增长13.7%;较呋喃丹增产显著,产量增长10.4%,效益增长12.0%。呋喃丹比对照略有增产,但效果达不到显著水平。棵棵无损除了对甘蔗害虫具有良好的防效而使产量损失减少外,由于该药剂在配方中添加了一种特有的高分子助剂,能促进甘蔗生长,显著地增加蔗茎产量。     

新化合物HNPC-A8008对鳞翅目害虫的活性及田间防治效果

[目的]评价新化合物HNPC-A8008[5-(3-氯烯丙基)氨基-1-(2,6-二氯-4-三氟甲基)苯基-4-三氟甲基亚磺酰基吡唑-3-腈)]对几种鳞翅目害虫的室内杀虫活性和田间防治效果。[方法]分别采用浸渍法和常规喷雾法进行室内毒力测定和田间药效试验。[结果]HNPC-A8008对鳞翅目害虫黏虫、菜青虫、小菜蛾、斜纹夜蛾48 h的LC50值分别为0.73、0.94、1.14、25.70 mg/L;在剂量为15、30、45 g a.i./hm2时,药后1、3、7 d对小菜蛾和菜青虫的田间防效分别超过了81.41%、89.80%;在剂量为30、60、90 g a.i./hm2时,药后14 d,对稻纵卷叶螟和二化螟的田间防效分别超过了66.99%、72.32%。[结论]新化合物HNPC-A8008在室内对多种鳞翅目害虫表现出很高的毒杀活性;对小菜蛾、菜青虫、稻纵卷叶螟、二化螟有良好的田间防治效果,且对作物和天敌安全。     

蓖麻提取物对蔬菜害虫的生物活性

采用不同提取方法从蓖麻籽中提取各种成分用于蔬菜害虫的杀虫试验。结果表明蓖麻碱对斜纹夜蛾的杀虫活性明显优于其他蓖麻毒性成分。对菜青虫杀虫活性二者活性相近,前者略优于后者,对小菜蛾的杀虫活性后者优于前者。根据本实验结果,与蓖麻提取物各种成分分开使用相比,采用蓖麻提取液的混合成分进行杀虫,宽杀虫谱更广,药效更高。     

森林病虫害监测中的无人机图像分割算法比较

以错分率、相对最终测量精度以及运行时间为评价标准,利用无人机采集的油松及沙棘正射图像为测试图像,对6种基于像素聚类及分水岭的图像分割算法的性能进行了定性分析及定量比较。实验结果表明,受灾林区图像的分割算法的性能与图像拍摄高度、噪声等因素密切相关。最后,给出了受灾林区无人机正射图像分割算法应用的指导性建议。     

Effectiveness of grain storage facilities and protectants in controlling stored-maize insect pests in a climate-risk prone area of Shire Valley,Southern Malawi

Shire Valley is one of Malawi's most vulnerable areas to climate change (CC). In addition to other impacts, CC is expected to affect storage insect pest status, and the efficacy of grain storage facilities and protectants. On-farm grain storage trials were therefore conducted in Shire Valley to assess the performance of storage facilities and grain protectants against storage insect pests. Eight smallholder farmers hosted the trials in Thyolo and Chikwawa districts. Seven grain storage treatments were evaluated for 32 weeks during two storage seasons: Neem leaf powder (NM), Actellic Super dust (ASD), ZeroFly^® bag (ZFB), Purdue Improved Crop Storage bag (PICS), Super Grain Bag (SGB), hermetic metal silo (MS) and untreated grain in a polypropylene bag (PP). Insect pest populations and grain damage increased with storage duration and differed significantly between treatments (p < 0.05). Grain stored in hermetic bags (PICS, SGB) sustained significantly lower (p < 0.05) insect damage and weight loss compared to other treatments across sites and seasons. The hermetic bags also outperformed the other treatments in suppressing insect numbers. However, germination rates of undamaged grains stored in the hermetic storage facilities (MS, PICS, SGB) for 40 weeks were extremely low (<15%) compared to that of undamaged grains from NM treatment (53–58%) and the other treatments (>75%) at both sites. The hermetic MS, ZFB bags, ASD and NM treatments did not effectively protect grain from insect damage. High in-store mean temperature (35.6 °C) and high initial grain moisture content (13.7%) may have negatively affected efficacy of some treatments and seed germination. Tribolium castaneum survival in the MS requires further investigation. The hermetic storage bags (PICS, SGB) can be recommended for long-term maize grain storage (≥32 weeks) by smallholder farmers in Shire Valley and other similar climate change-prone areas in sub-Saharan Africa.     

水果病虫害无损检测技术研究进展

水果的病害和虫害是影响水果品质等级鉴定的重要因素。水果在生长、加工、贮藏、运输过程中容易受到病菌侵染和害虫侵蚀,这将造成水果品质降低,同时对食品安全也会造成不良影响。本文综述了X射线成像技术、计算机视觉技术、核磁共振技术、光谱技术、新兴传感器技术等无损检测技术在水果病虫害识别与检测中的应用进展,并分析各技术的优势和劣势,重点介绍了高光谱成像技术在水果病虫害识别与检测方面的应用进展,分析存在的问题、展望发展趋势,为后续研究提供参考。     

Effect of CO2 modified atmosphere packaging on aflatoxin production in maize infested with Sitophilus zeamais

The weevil Sitophilus zeamais (Motschulsky), the maize weevil, is a pest of stored maize that can cause feeding damage and lead to the proliferation of toxigenic fungi. The application of modified atmospheres with a high concentration of CO₂ is an alternative method for the control of S. zeamais and the inhibition of fungal growth. The objectives of the study were to determine the effect of S. zeamais infestation, grain damage and grain moisture content on aflatoxin production by Aspergillus flavus on maize, and the impact of high CO₂ modified atmosphere packaging on pest infestation and aflatoxin production. Mycotoxin production was only recorded when maize was infested with S. zeamais and had A. flavus inoculum. However, production of mycotoxins was not recorded when the maize was mechanically damaged and stored at 18% moisture content, indicating that the biological activity of the insect was determinant in the production of mycotoxins. The high CO₂ modified atmosphere packaging tested (90% CO₂, 5% O₂ and 5% N₂) prevented mycotoxin production.