一株寄生柑橘介壳虫真菌的分离与鉴定

从感病柑橘介壳虫中分离和鉴定了一株菌株,为球黑孢霉菌[Nigrospora sphaerica(Sacc)Mason]。菌株在20~35℃范围内均能生长,25~30℃是菌落生长的最适温度区域。病菌在以淀粉为碳源的培养基上菌丝生长量较大,且菌丝生长丰度高。该菌对果糖、麦芽糖、乳糖、淀粉和葡萄糖为碳源的培养基的利用率均较高。该菌在以硫酸铵为氮源的培养基上菌丝生长量较大,其次是硝酸铵、甘氨酸和赖氨酸。     

检疫性害虫螺旋粉虱研究进展

螺旋粉虱是一种极具入侵性的外来有害昆虫,严重威胁着世界各地果树、蔬菜和园林植物的生产。由于螺旋粉虱具有寄主植物广泛、传播速度快、适应能力强和高度危险性等特点,被各国科研工作者和检疫部门所密切关注。就螺旋粉虱的生物学特性、在我国适生区及风险性、选择趋性、毒理学及天敌昆虫等方面的研究进行了探讨。     

农田生物多样性对昆虫的生态调控作用

随着农田作物的单一性种植,植食性昆虫暴发、物种流失等问题日益突出,化学农药大量应用于作物有害生物的防治更加剧了对农田生态系统的破坏和不稳定性.因此,从生物多样性-农田生态系统-植食性昆虫的相互关系入手,探讨生物多样性的保护及其在农业有害生物防控上的应用,回归农田生态系统动态平衡的生态调控举措,成为可持续发展农业领域中研究的焦点之一.本文综述了农田生物多样性对昆虫生态影响的重要性及其生态功能,进一步阐述了农田生物多样性在农业生产中的应用及前景.     

粮虫近红外高光谱图像的采集系统设计及实现

储粮活虫的准确检测是粮虫防治中科学决策的关键,为此,设计并构建了适于粮虫近红外高光谱图像采集的成像系统,系统主要由光谱成像单元、照明单元、位移单元、计算机和光箱五部分组成。试验结果表明,当曝光时间为3ms,位移台的移动速度为0.59mm/s时,系统所获取的小目标粮虫图像比较清晰,满足了后续粮虫光谱分析的需要。     

臭氧杀虫除霉实仓试验

用浓度为100～120ppm的O3在房式仓中对储藏的稻谷进行墙角局部(约2m^2)杀虫和防霉试验，3天后玉米象全部被杀死，6天后谷蠹全部被杀死，10天后赤拟谷盗全部被杀死，同时粮食的上、中、下层的平均水分由处理前的14．6％降至11．5％。经过1天处理后。粮堆原有轻微霉味的部位气味明显消除；经对样品的带菌量、菌相检测，处理5天后的粮食霉菌带菌量由处理前的3000个/g下降为45个/g，储藏性霉菌也由多种典型真菌减少到只有2种，而且检出率明显下降：黄曲霉由6％降为2％，灰绿曲霉由10％降为4％，白曲霉、黑曲霉和青霉均下降为零。经对处理前、处理结束时、处理后15天样品的出糙率、整精米率、黄粒米、脂肪酸值、粘度、裂纹率等品质指标进行测定，没有发现明显加速劣变的迹象。     

高效灭蚧灵的研制和防治桑白蚧试验

报道了高效灭蚧灵的研制过程、主要成分、杀虫原理、技术指标以及大田防治效果、对蚕桑的影响试验。本药剂含脂肪皂、表面活性剂、石油烃等,为浅棕色稠状膏体,pH:8.5—9.5,有效物≥72％,以触杀作用为主。防治桑白蚧的效果明显优于皂油合剂、洗衣粉、高效液体皂等已推广的农药,成本较低。桑园使用对蚕作安全,使用方法正确对桑树无药害。使用浓度:幼虫期喷药40—80倍(溶液),成虫期喷药夏秋季15—30倍,冬季和早春期5—10倍。     

Biological control of pigweeds (Amaranthus retroflexus, L. A. Powellii, S. Watson and A. bouchonii Thell.) with phytophagous insects, fungal pathogens and crop management

Pigweeds (Amaranthus spp.) are of economic importance worldwide. In Europe, Amaranthus retroflexus is one of the ten weed species of greatest economic importance. It is a serious problem weed in several field crops (e.g. maize), as well as in vegetables, orchards and grape vines. It is an annual spreading by seeds which have a long viabilityand are dispersed principally by wind and water, but also by machinery. There is great variability in seed germination which renders control with post-emergence herbicides difficult. In addition, triazine herbicide-resistant populations occur in ten European countries. The aim of this subproject of COST action 816 is to investigate the possibilities of classical and inundative biological control of Amaranthus spp., to characterize potentialbiological control agents and to develop methods for their integration with current phytosanitary measures in the target crops. The project was initiated with an extended literaturesurvey followed by field surveys for insects and pathogens associated with Amaranthus spp. in several European countries. Promising isolates of fungal pathogens have been tested ondetached leaves and whole plants, and initial studies on the application of pathogens causing damping off in seedlings have been made. Further, the variability of different provenances ofAmaranthus spp. in response to fungal attack has been investigated     

甘肃祁连山国家级自然保护区森林昆虫天敌种类调查（三）

本文报道甘肃祁连山国家级自然保护区双翅目(Diptera)天敌昆虫7科63种。     

The role of weeds in supporting biological diversity within crop fields*

Summary Weeds are major constraints on crop production, yet as part of the primary producers within farming systems, they may be important components of the agroecosystem. Using published literature, the role of weeds in arable systems for other above‐ground trophic levels are examined. In the UK, there is evidence that weed flora have changed over the past century, with some species declining in abundance, whereas others have increased. There is also some evidence for a decline in the size of arable weed seedbanks. Some of these changes reflect improved agricultural efficiency, changes to more winter‐sown crops in arable rotations and the use of more broad‐spectrum herbicide combinations. Interrogation of a database of records of phytophagous insects associated with plant species in the UK reveals that many arable weed species support a high diversity of insect species. Reductions in abundances of host plants may affect associated insects and other taxa. A number of insect groups and farmland birds have shown marked population declines over the past 30 years. Correlational studies indicate that many of these declines are associated with changes in agricultural practices. Certainly reductions in food availability in winter and for nestling birds in spring are implicated in the declines of several bird species, notably the grey partridge, Perdix perdix. Thus weeds have a role within agroecosystems in supporting biodiversity more generally. An understanding of weed competitivity and the importance of weeds for insects and birds may allow the identification of the most important weed species. This may form the first step in balancing the needs for weed control with the requirements for biodiversity and more sustainable production methods.     

Integrated Pest management in Forage Alfalfa

Alfalfa, Medicago sativa L., is among the most prized of forages, and is grown worldwide as a feed for all classes of livestock. It is one of man's oldest crops, and its cultivation probably predates recorded history. In addition to its versatility as a feed, alfalfa is well known for its ability to improve soil structure and, as a legume, is an effective source of biological nitrogen. As a perennial crop, alfalfa has a lifespan approaching 5 years, but in some areas of the world fields may remain productive for considerably longer. Such a long stand life affords ample time for the establishment and development of a diverse community structure by an abundance of organisms. In spite of system perturbations caused by frequent harvests and occasional pesticide applications, an alfalfa field provides a temporal stability which is uncommon among field crops. As a result of this stability, alfalfa supports an immense diversity of flora and fauna which, at times, exceeds that of riparian ecosystems. While most of alfalfa's inhabitants have little or no impact on it as a crop, a few are capable of causing extensive damage. Arthropods, plant pathogens, weeds, vertebrates, and plant parasitic nematodes can all cause significant yield and/or quality reductions and frequently contribute to shortening the productive life of the stand. This paper reviews the major strategies which have been developed to manage many of these alfalfa pests including: host plant resistance; cultural controls, such as harvest strategies, irrigation management, sanitation, planting schedules, and crop rotation; mechanical and physical controls; chemical control; and biological controls. Multiple pest interactions, e.g. insect-insect; insect-disease; insect-weed, and their management are discussed. Potential conflicts arising from the use of strategies which may reduce one pest but exacerbate others are also examined. A cross index of management strategies and their role in managing multiple pests is provided. Computer models, both ecological and economic, and their role in alfalfa pest management are discussed. Selected information sources on alfalfa and alfalfa IPM available over the Internet are listed. Alfalfa's role in the agricultural landscape, as it relates to pests, natural enemies, and pest management in other cropping systems as well as its role in crop rotation, is considered.