蝗虫的发生与防控

蝗虫暴发引起的灾害是全球重要的生物灾害,可影响到全世界十分之一的人口。自2019年,东部非洲、西亚、南亚多个国家遭遇严重的沙漠蝗虫灾害,这场蝗灾不但对该区域的粮食安全构成严重威胁,而且还有可能引发严重的人道主义危机。为了制定合理的防治方案,实施有效防控,避免大规模蝗灾的发生,需要掌握蝗虫的生物学、生态学、暴发和为害规律、防治策略和技术特点及其进展等。本文介绍了世界各地包括沙漠蝗、飞蝗、澳大利亚疫蝗在内的11种可以引起灾害的重要种类的主要分布、为害和特性,并对国内外蝗虫防治策略、技术进展进行了重点综述。最后,针对目前蝗虫防治存在的问题提出了相应建议。     

中国北方草地蝗虫学研究概况

<正> 就目前所知,我国严重为害草地的害虫约计40余种(田畴等,1988),其中主要为蝗虫类。其为害遍布我国北方草地。仅在内蒙古,每年发生面积约500～1000万亩,在为害严重的局部地区其虫口密度达200头/m~2。蝗虫的大发     

我国蝗虫暴发成灾的现状及其持续控制对策

概述并分析了我国蝗虫暴发成灾的现状及原因 ,认为全球气候变暖和区域性气候异常、人类活动的影响、监测预警技术手段落后、成灾蝗种增多和发生为害类型复杂、蝗虫研究队伍锐减及基础理论与高新技术研究滞后导致了近年来蝗虫的暴发成灾。对此 ,作者从蝗虫灾害的规律性、监测预警高新技术和综合治理技术等方面提出了实现蝗灾可持续控制的对策     

蝗虫成灾规律、影响因素及防控技术研究进展

蝗虫是最重要的全球农牧业害虫之一,其灾害不仅强烈影响生态系统功能和稳定性,还带来严重的经济损失。因蝗虫食性杂、适应性强、聚集为害等特点使其可持续治理成为一项复杂而长期的艰巨工作。本文从蝗虫灾变发生规律、影响因素(自身因素、非生物和生物因素)以及当前有效防控方法与技术进行综述,并从蝗虫种群动态变化规律以及其有效防控的理论与技术提出今后的研究方向,为将来蝗虫发生的内在机制研究以及对其进行绿色防控技术探索提供基础。     

新疆蝗虫及其监控技术研究进展

因蝗虫种群种类多、分布范围广,导致新疆是我国蝗虫灾害发生最突出、最典型的地区,也是遭受邻国蝗虫跨境危害最严重的地区。本文概述了几十年来新疆蝗虫基础理论研究及监测预警与防控技术进展,同时总结了中哈边境蝗虫跨境迁飞过程及雷达监测的最新研究结果,并就中亚迁飞场理论和实证研究、区域迁飞害虫监测网络平台建立和生物防治技术三个方面进行了展望,以期为监测和治理新疆本地蝗虫及西北边境迁飞害虫提供科学依据和技术支撑。     

内蒙古锡林河流域不同生境中蝗虫种类组成的分析

本文对内蒙古锡林河流域不同生境中蝗虫种类发生的情况进行了分析。经过系统取样和大面积扫网调查,共采集到蝗虫21种,这些种类在各生境中出现的情况,与生境的复杂程度存在很大的关系。在复杂的生境中,蝗虫种类最丰富。根据锡林河流域不同生境中蝗虫种类发生的情况,经过比较分析,我们认为在该区域存在的沙带生境是典型草原的“蝗虫库”。“蝗虫库”的存在,对牧业生产构成一定的潜在威胁。经存在度分析表明,一些常见的种类,生态分布幅度宽,同时,它们又是当地的优势种害虫,为害大,是重点防治对象。     

感谢苏联治蝗专家对我们的伟大援助

蝗虫是我国危险性的大害虫,不仅在沿海的河北、江苏、山东等省,连年猖獗为害;新疆也是常常闹蝗灾的地区,并由于在新疆为害的蝗虫不只是飞蝗,还有红胫戟纹蝗、西伯利亚蝗及意大利蝗等多种,再加上新疆地面辽阔,蝗虫发生的中心都是分布在交通困难和生活条件极度恶劣的地区,这对于治蝗工作增加极大困难。解放后第一年全国十多个省市都发生蝗虫猖獗为害,当时,我们对这样大规模的治蝗工     

烟粉虱在我国的发生为害现状及其非化学控制对策(英文)

烟粉虱 (BemisiatabaciGennadius )是热带、亚热带和温带地区主要害虫之一。烟粉虱早在 40年代在我国就已有记载 ,现广泛分布于我国的 2 2个省市。过去烟粉虱在我国为害并不严重 ,近年来在广东和北京等地已成为蔬菜和园艺作物生产的严重障碍。除直接为害外 ,烟粉虱可传播番茄和南瓜曲叶病等5种难于防治的病毒病。到目前为止 ,已报到 1 8种寄生性天敌、1 7种捕食性天敌及 1种虫生真菌。本文简要慨述烟粉虱在我国的发生为害与传毒现状 ,并结合我国的具体情况提出非化学控制烟粉虱的对策。     

蝗虫灾害的特点、成因和生态学治理

介绍了蝗虫灾害发生的特点与发生动态,分析了蝗虫害害形成和再猖獗的主要原因。探讨了黄河流域和广大特区蝗虫灾害特点,提出了蝗虫灾害的可持续控制研究建议与生态学治理对策。     

影响哈密地区蝗虫大发生的气象因子研究

蝗虫是新疆农牧业生产的严重害虫之一 ,蝗虫的发生与气象条件有着密切的关系。从前一年秋季到当年夏季气温偏高 ,降水偏少 ,且 5～ 8月气温具有周期性的变化 ,有利于蝗虫大范围发生 ,当 5～ 8月气温偏高的情况下 ,在新疆干旱地区某段时间适度的降水偏多 ,期间交替某段时间暖干 ,对蝗虫灾害的发生影响不大 ,冬季气候条件对蝗虫发生程度影响较小。建立草原蝗虫灾情监测预测系统 ,及时了解气候和蝗虫生长情况 ,在现有的防御体系下有目的进行防治 ,是控制蝗害、保护草原的根本方法之一。     

国际蝗虫灾害的防治策略和技术：现状与展望

简要地综述了国际上对蝗虫灾害管理策略与控制技术的发展现状,包括：监测与预警技术、化学防治、生物防治、综合管理对策以及目前的研究热点方向。比较分析了国际、国内蝗虫发生及其治理中存在问题的异同。国际上控制蝗虫灾害的理论、技术、措施、对策,对中国有重要的借鉴作用。一般来说, 控制蝗虫灾害的IPM计划中应该包括：在策略上,强调提前预防压制优于后期灭杀处理;在规律认识上,重视基础生物学和生态学的研究,并将之模型化和标准化;在测报方法上,积极发展和改善监测预警技术水平,将地理信息系统(GIS）和遥感（RS）技术集成引入到防治决策的整体系统中,使信息能够快速、准确地传递;在防治手段上,注意新型防治药剂和施药技术的研究开发和集成,增加用药效果;在天敌利用和环境保护方面,充分认识和评估自然天敌的控制作用,正确地估计防治效益和挽回的损失,重视对环境价值的评价;同时加强多个地区间的联合与协调。     

Microbial and protozoan pathogens of grasshoppers and locusts as potential biocontrol agents

Worldwide, grasshoppers and locusts destroy several billion dollars (US) worth of crops every year. The known microbial and protozoan pathogens of grasshoppers and locusts are reviewed. They may be valuable control agents, particularly for some of the economically devastating locust species in Africa and Asia, and grasshopper species in North America and Asia. Aspects of the pathogenic process, if known, of fungi, protozoa, viruses and rickettsia towards acridids are discussed. Finally, production, formulation and application of these biocontrol agents are reviewed.     

Modelling locust foraging: How and why food affects group formation

Locusts are short horned grasshoppers that exhibit two behaviour types depending on their local population density. These are: solitarious, where they will actively avoid other locusts, and gregarious where they will seek them out. It is in this gregarious state that locusts can form massive and destructive flying swarms or plagues. However, these swarms are usually preceded by the aggregation of juvenile wingless locust nymphs. In this paper we attempt to understand how the distribution of food resources affect the group formation process. We do this by introducing a multi-population partial differential equation model that includes non-local locust interactions, local locust and food interactions, and gregarisation. Our results suggest that, food acts to increase the maximum density of locust groups, lowers the percentage of the population that needs to be gregarious for group formation, and decreases both the required density of locusts and time for group formation around an optimal food width. Finally, by looking at foraging efficiency within the numerical experiments we find that there exists a foraging advantage to being gregarious.     

白洋淀蝗虫分布调查及其防治

1998～ 2 0 0 2年对白洋淀蝗区的蝗虫种类、分布、优势种群及蝗区水文、植被、土壤、天敌等进行了调查研究。调查表明 ,白洋淀蝗区有蝗总科昆虫 3 0种 ,隶属 6总科、2 2属 ,分布于白洋淀淀内湖泊蝗区、淀边内涝蝗区和淀外河泛蝗区 ;明确以东亚飞蝗Locustamigratoriamanilensis (Meyen)为主的 5个蝗虫优势种群及生活史 ,并根据不同蝗区类型 ,提出了蝗区治理区划、生态治理技术、应急化学防治等 3项防治技术和“两改一加强”防治手段     

警惕沙漠蝗的猖獗发生

沙漠蝗在史前期就是北非、西亚和印度等热带荒漠地区的河谷与绿洲上的农业大害虫。我国云南和西藏自治区的聂拉木均有沙漠蝗的分布记载 ,虽尚未发生灾害 ,但是沙漠蝗猖獗发生的最大扩散区已达我国云南接壤的缅甸和西藏接壤的尼泊尔、印度。故我国的西藏自治区和云南省的有关边防及农业植物保护机构应予以高度重视并加强监测和预警 ,谨防沙漠蝗的发生危害     

Effects of a combined infection with Paranosema locustae and Beauveria bassiana on Locusta migratoria and its gut microflora

Even though Paranosema locustae is widely used in China as a biological agent for controlling grasshoppers,the mortality rate is initially quite low.This study sought to determine whether the simultaneous use of P.locustae and Beauveria bassiana would be a more effective control strategy.Additionally,changes in the intestinal microbial communities of migratory locusts infected with the two pathogens were analyzed to investigate the roles of gut microbes in pathogen-host interactions.The mortality rate of locusts inoculated with B.bassiana and P.locustae simultaneously was not significantly higher than expected but the mortality rates of locusts inoculated with B.bassiana 3,6,and 9 days after inoculation with P.locustae were significantly higher than if their effects were additive,indicating synergism.A MiSeq analysis found that Weissella was the most common bacterium,representing 41.48%and 51.62%of the total bacteria in the mid-and hindguts,respectively,and the bacterial declines were greatest during dual infections with B.bassiana and P.locustae.The appropriately timed combined application of P.locustae and B.bassiana was more effective against locusts than either treatment alone.Moreover,the combined inoculation of the two pathogens changed the gut microflora of locusts,indicating the potential relevancy of their synergistic effects on locust control.     

Behavioural changes in Schistocerca gregaria following infection with a fungal pathogen: implications for susceptibility to predation

1. Field observations have indicated that infection of locusts and grasshoppers by the fungal entomopathogen Metarhizium anisopliae var. acridum may result in a substantial increase in the host's susceptibility to predation, before death is caused directly by the disease. 2. Laboratory experiments were conducted to examine how the behaviour of the desert locust Schistocerca gregaria Forskål changes following infection by M. anisopliae var. acridum to explore some potential mechanisms underlying this phenomenon. 3. In the first experiment, which involved monitoring general locust activity in small cages throughout the disease incubation period, infected locusts were observed to increase locomotion and bodily movement from 3 days after infection until death (average survival time of 11 days). There was some evidence of reduced feeding and mating behaviour following infection. 4. In a second experiment, locusts were exposed individually to a simulated predator attack and the initiation and strength of any escape responses were measured. Infected locusts were observed to have a reduced escape capability (both the propensity to escape and the strength of the response). In contrast to the relatively early changes in general activity observed in the first experiment, this was only apparent at the late stages of infection shortly before death. 5. Both an increase in movement and general apparency early in the infection process, and reduced escape capability late on, suggest mechanisms whereby the susceptibility of locusts and grasshoppers to predation might be enhanced following infection with M. anisopliae var. acridum.     

持续治理飞蝗灾害的新对策

该文通过对飞蝗Locusta migratoria为害特性的描述以及本世纪我国飞蝗防治历史的回顾,对各个时期的飞蝗治理策略的特点及不足进行了分析,并在总结我国近几年飞蝗生物治理理论研究与实践的基础上,提出了21世纪我国飞蝗生物治理的对策,即逐步扩大采用生物防治措施,增强如蝗虫微孢子虫生物防治制剂及天敌的控制作用,在飞蝗虫口密度中等或较低时,采用生物防治制剂为主,阻止或延缓中、低密度的飞蝗向高密度群居型的发展进程;在飞蝗虫口密度高时,可采用化防(昆虫生长调节剂等)与生防(如微孢子虫)配合使用,以迅速压低虫口密度,防治其迁飞为害,同时也可使蝗虫微孢子虫疾病长期流行于蝗群中,抑制飞蝗种群数量的增长。并积极探讨信息化合物对飞蝗行为的调控作用。     

Effects of Rehydration on the Conidial Viability of Metarhizium flavoviride Mycopesticide Formulations

The rehydration of dried conidia of Metarhizium flavoviride was investigated in an attempt to increase speed of kill of locusts and grasshoppers by formulations of this fungus. Conidia were dried to 4-5% moisture content with no apparent adverse effects on viability, but rapid rehydration (by putting dried conidia directly in free water) reduced viability. Rehydration in an atmosphere of high humidity allowed dry conidia to absorb sufficient moisture to avoid imbibition damage. Rehydrating and pre-germinating conidia prior to spraying (in an oil-based formulation) on to the desert locust, Schistocerca gregaria, did not decrease the time to death, suggesting that moisture uptake by dry conidia on the desert locust cuticle is easily achieved.