信息素及其在储粮害虫检测中的应用

在粮食储藏过程中,准确检测粮堆内害虫种类和密度是害虫综合防治的重要依据,而传统检测方法存在工作量大、检测结果滞后等缺点,因此寻找新的检测手段具有重要意义。研究发现,昆虫信息素具有安全、绿色、微量、高效等特点,可用于储粮害虫的检测与控制。概述了昆虫信息素的结构鉴定、人工合成、采集方法,主要分析了信息素在储粮害虫监测诱捕检测法和信息素成分分析法中的应用研究,并讨论了信息素在上述两种检测方法的应用中所存在的难题,以期为储粮害虫检测技术的发展提供参考。     

The Phorbol Ester Fraction from Jatropha curcas Seed Oil: Potential and Limits for Crop Protection against Insect Pests

The physic nut shrub, Jatropha curcas (Euphorbiaceae), has been considered as a “miracle tree”, particularly as a source of alternate fuel. Various extracts of the plant have been reported to have insecticidal/acaricidal or molluscicidal/anthelminthic activities on vectors of medical or veterinary interest or on agricultural or non-agricultural pests. Among those extracts, the phorbol ester fraction from seed oil has been reported as a promising candidate for use as a plant-derived protectant of a variety of crops, from a range of pre-harvest and post-harvest insect pests. However, such extracts have not been widely used, despite the “boom” in the development of the crop in the tropics during recent years, and societal concerns about overuse of systemic chemical pesticides. There are many potential explanations to such a lack of use of Jatropha insecticidal extracts. On the one hand, the application of extracts potentially harmful to human health on stored food grain, might not be relevant. The problem of decomposition of phorbol esters and other compounds toxic to crop pests in the field needing further evaluation before such extracts can be widely used, may also be a partial explanation. High variability of phorbol ester content and hence of insecticidal activity among physic nut cultivars/ecotypes may be another. Phytotoxicity to crops may be further limitation. Apparent obstacles to a wider application of such extracts are the costs and problems involved with registration and legal approval. On the other hand, more studies should be conducted on molluscicidal activity on slugs and land snails which are major pests of crops, particularly in conservation agriculture systems. Further evaluation of toxicity to natural enemies of insect pests and studies on other beneficial insects such as pollinators are also needed.     

Effect of “soft-electron” (low-energy electron) treatment on three stored-product insect pests

Developmental stages of three stored-product insect pests viz. Tribolium castaneum (Herbst), Plodia interpunctella (Hübner) and Callosobruchus chinensis (L.) were exposed to “soft electrons”, low-energy electrons. Soft electrons at an acceleration voltage of 170 kV effectively inactivated eggs, larvae and pupae of T. castaneum and P. interpunctella. The adults of T. castaneum and P. interpunctella were inactivated by treatment for 10 min (4.8 kGy) and 15 min (7.2 kGy), respectively. Soft electrons at 170 kV also inactivated the eggs of C. chinensis effectively. The adults of C. chinensis survived a 15 min exposure (7.2 kGy), but were inactivated having lost the ability to walk after a 5 min exposure (2.4 kGy). Soft electrons at 170 kV could not completely inactivate the larvae of C. chinensis inside beans, because the electrons with low penetration did not reach the larvae due to the shield of beans. The movement of T. castaneum larvae exposed to soft electrons was sluggish for several days, and then the larvae died with their hindguts emerged from their posterior ends 17 days after the treatment. DNA comet assay of cells of P. interpunctella larvae indicated that soft electrons at 170 kV damaged DNA in the larvae.     

A comparison between the impact of sulfuryl fluoride and methyl bromide fumigations on stored-product insect populations in UK flour mills

The impact of sulfuryl fluoride and methyl bromide fumigations upon populations of flour beetles (Tribolium spp.) and of Mediterranean flour moth (Ephestia kuehniella), was evaluated in UK flour mills. Two mills were selected for fumigation with sulfuryl fluoride and two mills for fumigation with methyl bromide. Traps baited with aggregation pheromone lure and an oil-based food attractant were used to monitor populations of rust red flour beetle and confused flour beetle. For the monitoring of Mediterranean flour moth, sticky traps baited with a pheromone lure were used. Traps were placed inside the mill buildings within the areas selected for fumigation. Infestation levels of the insects were monitored for 1–2 weeks prior to fumigation and for a total of 12 weeks post-fumigation. From the calculated percentage reduction in insects trapped per day during the post-fumigation monitoring period it was clear that sulfuryl fluoride fumigations had good efficacy against infestations of Tribolium confusum and E. kuehniella, and compared very favourably with the efficacy of methyl bromide. The absence of T. castaneum in traps pre-fumigation meant that the efficacy of sulfuryl fluoride against this species could not be assessed in this investigation. Indian meal moth, Plodia interpunctella, was also detected in some mills but only post-fumigation.     

10%龙灯·喜乐龙+20%噻虫胺防治甘蔗害虫田间药效试验

为了探索10%龙灯·喜乐龙与20%噻虫胺对甘蔗螟虫及蓟马、蚜虫的防治效果及用量,2019年在云南省陇川县蔗区进行试验。试验结果表明,龙灯·喜乐龙与噻虫胺对甘蔗螟虫具有较好的防治效果,10%龙灯·喜乐龙SC+20%噻虫胺(13500+1350 g/hm²、1800+1800 g/hm²、2250+2250 g/hm²)对甘蔗螟虫防治效果显著,与空白对照比,对螟害株的防治效果分别达到了100%、97.56%、96.34%,对螟害节的防治效果分别达到了100%、98.98%、98.48%。     

基于改进的Faster R-CNN的小目标储粮害虫检测研究

针对小目标储粮害虫图像的检测问题,提出了一种基于特征金字塔网络的Faster R-CNN改进模型对图像中的小目标进行检测。本文以5种常见的储粮害虫为检测目标,样本中通过随机组合的方式混合不同种类的储粮害虫进行拍照取样,通过对原始图像数据进行目标扩充后构建了含942张储粮害虫图像的数据集（CSGP）。在改进模型的特征金字塔网络结构中,特征提取网络产生的高层特征图通过下采样方式逐步对底层特征图进行融合,生成适合多尺度目标检测的特征图。实验结果表明,采用训练集目标扩充的方式,储粮害虫图像的目标检测结果mAP提升了2.21%;改进后的模型进一步使得储粮害虫图像检测的mAP达到96.69%。最后,设计了一套粮仓内的储粮害虫监测系统。     

基于图像智能识别的农作物防治系统设计与开发

农药播撒在农作生产环节中至关重要,针对我国存在农药漏用、乱用的现象,设计的农作物防治系统将信息技术与农业生产相结合,基于Spring MVC框架,构建移动端微信小程序与后端管理系统,集合了病虫害图像识别、疫区防治信息维护和代理防控等模块.系统覆盖"播种—查虫—识别—防治"的业务闭环,提高了农业生产效率,助力我国农业信息...     

酒曲害虫的发生、危害与大曲生产周期的关系研究

结合酒曲生产周期研究了酒曲发生害虫的危害过程及大曲贮存时间与害虫量、危害损失程度的关系。研究结果表明,危害新曲的虫源主要来自于曲库。曲虫从大曲高温发酵后的保温排潮期开始入侵危害,曲库贮存期发生危害最严重。在贮存期的前４个月,曲早数量上升,随后逐渐减少。曲早危害损失随贮存的时间而增加。     

The recent disciplinal progresses of agricultural entomology in China

In this paper, four recent advances and achievements of China in agricultural insect research, namely, on the genome of silkworm (Bombyx mori Linnaeus), on the geographical differentiation and regional migration of cotton bollworm (Helicoverpa armigera (Hübner)), on the standardized monitoring techniques for safety of honey bee (Apis mellifera Linnaeus) products, and on the virus transmission property of small brown planthopper (Laodelphax striatellus (Fallen)) as well as the interactions between vector and rice stripe virus (RSV), were reported. All of these researches are very important for controlling agricultural insect pests and the diseases they transmit, accelerating the molecular biological research of silkworm, and promoting the international trade of honey bee products. Most of these achievements mentioned above have got the national, provincial, ministerial or municipal awards on science and technology.     

Effect of thiamethoxam partial grain treatment to Rhyzopertha dominica (F.) and Sitophilus oryzae (L.) adults

The efficacy of partial treatment of two commodities (wheat and rice) with thiamethoxam against adults of Rhyzopertha dominica (F.) and Sitophilus oryzae (F.) was tested by mixing different proportions of thiamethoxam-treated and untreated grains. Thiamethoxam was applied to these grains in two different doses 1 and 5 ppm, while the percentage of the treated grain quantity ranged between 0 and 100%. Adult mortality was recorded after time exposure intervals of 7 and 14 d. Irrespectively of the dose, adult mortality was raised with increase in the percentage of treated kernels as well as the exposure time. Applications of thiamethoxam on wheat were more effective than on rice and on R. dominica than on S. oryzae, especially at 1 ppm, for both exposure intervals. The effective “critical” percentage, causing control similar to 100% treatment, of thiamethoxam to grain mass at 5 ppm was 50% for both species. For the examined scenario of partial treatment, thiamethoxam found to be effective against the tested species which makes it a candidate for use in the stored grain protection.