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1.
茶尺蠖生物防治进展   总被引:3,自引:0,他引:3  
茶尺蠖Ectropis obliqua Prout是茶园中的重要害虫,对它的生物防治研究国内已做了较多的工作.本文从茶尺蠖的研究基础-大量饲养和它的病原性天敌、捕食性天敌、寄生性天敌及信息素等方面对茶尺蠖的生物防治研究作了综述.  相似文献   

2.
烟粉虱Bemisia tabaci Gennadius是一种广泛分布于世界各地的多食性害虫,对我国多个省市区的农作物和观赏植物造成了严重的危害。化学杀虫剂的大量使用在杀伤天敌的同时使烟粉虱产生了不同程度的抗性,防治越来越困难;相较于化学防治,在不同地区筛选有效的天敌对烟粉虱进行生物防治是对烟粉虱进行有效控制的重要方法。我国报道的捕食性天敌共计26科109种,寄生性天敌共计2科59种。烟粉虱防治过程中由于单一的防治效果不理想,联合多个天敌资源的利用是增加对烟粉虱的生物防治效果的重要手段。本文通过对我国烟粉虱捕食性和寄生性天敌种类系统全面的整理,同时对烟粉虱优势种天敌中的单种或者多种组合利用后对烟粉虱的的控害潜能进行综述,以期为烟粉虱天敌昆虫种类的筛选和实现高效的生物防治提供科学依据。  相似文献   

3.
美国白蛾Hyphantria cunea(Drury)是国家林业和草原局的重点防控对象,也是我国重大外来林业检疫性有害生物.现阶段美国白蛾在我国的种群密度持续增加和扩散,缺乏有效天敌的控制应该是重要的原因之一.本文综述了国内、外美国白蛾的捕食性和寄生性天敌的种类.捕食性天敌主要包括昆虫、蜘蛛、两栖类和鸟类,整理出国外报道的捕食性天敌名录119种,国内捕食性天敌名录29种;寄生性天敌主要包括寄生蜂和寄生蝇类,整理出国外报道的寄生性天敌名录47种,国内寄生性天敌名录53种.本文回顾了我国在美国白蛾天敌利用方面取得的阶段成果,并针对将来天敌复合体的应用和原产地天敌的引进提出了展望.  相似文献   

4.
小麦-油菜邻作对麦田主要害虫和天敌的影响   总被引:1,自引:0,他引:1  
应用昆虫群落生态学的群落特性分析方法,于2008年和2009年在河北省邯郸市调查了小麦与油菜邻作对麦田蚜虫及主要天敌群落的构成、丰富度和稳定性的影响.结果表明:小麦与油菜田间昆虫群落的组成相似,主要田间害虫为蚜虫,其捕食性天敌包括瓢虫类、草蛉类、蜘蛛类和食蚜蝇,寄生性天敌为蚜茧蜂;两年间田间昆虫群落的组成有一定的变化,但均表现为邻近油菜的麦田蚜虫丰富度最低,捕食性天敌和寄生性天敌的丰富度最高;邻近油菜的麦田昆虫群落、麦蚜亚群落、捕食性天敌亚群落的稳定性高,远离油菜的稳定性低.该模式可以有效保护和利用天敌,增强田间自然天敌对害虫的控制能力.  相似文献   

5.
本文对蚜虫性信息紊成分的分离与鉴定、蚜虫性信息素对蚜虫及其天敌行为调节作用等方面的研究现状作了概述.  相似文献   

6.
天敌是影响害虫种群动态的重要因素。一般认为天敌对害虫作用的方式,主要是通过直接的捕食或寄生。事实上,天敌还可以通过捕食或寄生过程中产生的"威吓"等非直接致死效应(Non-lethal effects)或胁迫作用(Stress),影响着害虫的生长发育、繁殖。有时这种天敌存在的非直接致死效应对害虫产生的负面影响甚至比天敌对害虫的直接捕食作用还强。显然,评价天敌作用时,除了计算天敌对害虫的直接捕食或寄生的效率,还应考虑天敌存在时对害虫的非直接致死效应。本文基于作者及前人的研究,分别论述了捕食性天敌、寄生性天敌对害虫的非直接致死效应,解析了环境变化对天敌非直接致死效应的影响,探讨了这种非直接致死效应的可能机制,提出了未来的研究发展方向。  相似文献   

7.
戈峰  丁岩钦 《昆虫学报》1996,39(3):266-273
为充分发挥棉田捕食性天敌的生态调控作用,本文根据田间调查与室内测定的结果,以能量为统一单位,计算出了棉田捕食性瓢虫、蝽类、蜘蛛及所有捕食性天敌类种群的能流参数值,分析和比较了不同播种期、套间作和免耕法对棉田捕食性天敌种群能量获取利用的作用特点,总结出了各类天敌在不同类型棉田对害虫的控制作用规律,评价了它们在棉田生态系统中的作用与地位。  相似文献   

8.
苏丽  戈峰  刘向辉 《昆虫学报》2002,45(6):777-784
分析比较了化学防治对8种不同类型棉田害虫、捕食性天敌群落多样性的影响。研究结果表明,化学防治对棉田害虫、捕食性天敌群落的多样性指数、均匀性指数、丰富度及个体数的变化有较大的影响,尤其对捕食性天敌群落的影响显著。但这种作用依不同类型棉田或棉花不同生育阶段而异:化学防治对套作棉田害虫、捕食性天敌群落的影响较小,而对单作棉田和豆间棉棉田害虫、捕食性天敌群落的影响较大;晚播棉田害虫与捕食性天敌群落较早播棉田受化学防治的影响更大;化学防治对免耕棉田害虫、天敌群落的影响更大,非免耕棉田害虫、捕食性天敌群落受其干扰较小;春套棉边害虫、捕食性天敌群落与其它棉田类型相比,受化学防治的影响较少;棉花害虫在棉花生育前期对化学防治较棉花生育后期敏感,而捕食性天敌在棉花整个生育期均对化学防治敏感。  相似文献   

9.
稻田生境调节和捕食性天敌对稻飞虱的控制作用   总被引:12,自引:4,他引:8  
广东省四会市大沙镇1973年开展以发挥天敌作用为主的水稻害虫综合防治,20多年来稻飞虱一直没有大发生,且发生程度低于临近地区。本文试图从理论上解释这一现象。通过改善天敌的生境条件,捕食性天敌群落种库中天敌的种类和多样性增多,天敌各落重建和发展的能力增强,重建后群落的种类数量和多样性均高于临近地区,最终使得天敌群落对稻飞虱的控制作用增强,98%以上的稻田飞虱的数量常在防治指标以下。  相似文献   

10.
中稻田三种飞虱的捕食性天敌优势种及农药对天敌的影响   总被引:2,自引:0,他引:2  
对两优0923非防治的中稻田白背飞虱、灰飞虱和褐飞虱与其天敌间的关系,采用灰色关联度法、生态位分析方法,对盆拍法调查的3种飞虱与其捕食性天敌在数量、时间和空间三方面关系进行分析,对每一种天敌对应的关联度、生态位重叠指数和相似性比例等参数标准化后的密切指数相加,按照密切指数值之和大小排序,评判3种飞虱捕食性天敌优势种.并用同样方法分析常规防治田农药对飞虱捕食性天敌的影响,以期为合理施药,科学保护和利用天敌优势种提供科学依据,其结果是,非防治田白背飞虱前三位天敌是条纹蝇虎、草间小黑蛛和锥腹肖蛸;灰飞虱的是八斑球腹蛛、茶色新园蛛和锥腹肖蛸;褐飞虱的是纵条蝇狮、四点亮腹蛛和黑肩绿盲蝽.防治田白背飞虱前三位天敌是条纹蝇虎、草间小黑蛛和锥腹肖蛸;灰飞虱的是拟水狼蛛、四点亮腹蛛和草间小黑蛛;褐飞虱的是黑肩绿盲蝽、拟水狼蛛和四点亮腹蛛.盆拍法的防治田和非防治田之间3种飞虱前三位的相同天敌,白背飞虱完全相同,灰飞虱没有相同天敌,褐飞虱的是黑肩绿盲蝽和四点亮腹蛛.飞虱与天敌在时间和数量关系上,扫网法的防治田和非防治田之间3种飞虱前三位的相同天敌,白背飞虱的是锥腹肖蛸和四点亮腹蛛,灰飞虱完全相同,褐飞虱的是纵条蝇狮和条纹影虎.两种稻田的差异主要是农药杀伤了飞虱,使飞虱数量减少,并对天敌有一定杀伤力,进而影响到天敌的发生规律.非防治田的盆拍法和扫网法之间,3种飞虱前三位相同的天敌,白背飞虱的是锥腹肖蛸,灰飞虱的也是锥腹肖蛸,褐飞虱的是纵条蝇狮.防治田两调查方法结果之间,白背飞虱的是锥腹肖蛸,灰飞虱和褐飞虱前3位天敌中没有相同天敌,其差异主要是两法调查稻株的部位不同所致.  相似文献   

11.
In order to establish and screen nucleic acid test (NAT) quality control indicators for blood donor samples, CT value of each test item were detected by NAT, internal and external quality controls, the number of unsuccessful mixed samples, the split positive rate, the rate of detection efficiency, and the equipment failure rate were collected. The "instant method" is used to establish the Levey-Jennings quality control chart, the mixed test positive rate, the rate of unqualified sample. Possion distribution is used to establish the quality control chart, and it is easily to operate and monitor NAT effectively. The results displayed that quality control charts were established, including unqualified sample Possion distribution quality control chart, the rate of equipment failure quality control chart, the failure rate of reagent batch and inefficient quality control chart, test result positive of Possion distribution quality control chart, quality control charts of NAT positive Possion distribution probability, the rate of split positive quality control charts, quality control charts of unsuccessful mixed samples, quality control chart of reagents effective rate, internal quality control chart, correctness, and NAT qualitative quality control chart. The study established quality control indicators throughout the whole NAT process, which were able to effectively improve NAT quality control and the efficacy of laboratory management.  相似文献   

12.
13.
A CPG control mechanism is proposed for hopping motion control of biped robot in unpredictable environment.Based on analysis of robot motion and biological observation of animal's control mechanism,the motion control task is divided into two simple parts:motion sequence control and output force control.Inspired by a two-level CPG model,a two-level CPG control mechanism is constructed to coordinate the drivers of robot joint,while various feedback information are introduced into the control mechanism.Interneurons within the control mechanism are modeled to generate motion rhythm and pattern promptly for motion sequence control; motoneurons are modeled to control output forces of joint drivers in real time according to feedbacks.The control system can perceive changes caused by unknown perturbations and environment changes according to feedback information,and adapt to unpredictable environment by adjusting outputs of neurons.The control mechanism is applied to a biped hopping robot in unpredictable environment on simulation platform,and stable adaptive motions are obtained.  相似文献   

14.
目的:探讨基于RNA干扰CMTM7对肺腺癌A549细胞凋亡的影响。方法:选择肺腺癌A549细胞株分为si RNA组、阴性对照组与空白对照组,在对数生长的A549细胞中转染RNA干扰CMTM7载体、脂质体空载体和不进行转染,观察A549细胞的生长、凋亡与细胞周期状况。结果:MTT实验显示si RNA转染组的抑制率明显高于阴性对照组和空白对照组(P0.05),阴性对照组与空白对照组的对比无明显差异(P0.05)。流式细胞术实验表明si RNA转染组的细胞凋亡率明显高于阴性对照组和空白对照组(P0.05),阴性对照组与空白对照组的对比无明显差异(P0.05)。流式细胞术实验表明si RNA转染组的G0/G1期细胞数目较阴性对照组和空白对照组增多明显(P0.05),同时si RNA转染组的S、G2/M期细胞数目较阴性对照组和空白对照组明显减少(P0.05),阴性对照组和空白对照组对比差异无统计学意义(P0.05)。结论:RNA干扰CMTM7能够促进肺腺癌A549细胞凋亡,抑制肿瘤细胞的生长,其作用机制可能通过干扰细胞周期而实现。  相似文献   

15.
运用层次分析法对豚草生物防治、化学防治和不实施任何防治措施的空白对照进行综合评价.对3种防治措施的综合效益和综合成本进行计算和排序,作为选择豚草防治措施的准则.结果表明:豚草生物防治所获得的综合效益最高,综合成本最低;空白对照的综合效益最低,综合成本最高;化学防治的综合效益和综合成本居中.豚草生物防治效益成本比最高,说明其是一种最为理想的防治措施,值得推广应用.  相似文献   

16.
豚草防治措施综合评价   总被引:3,自引:0,他引:3  
运用层次分析法对豚草生物防治、化学防治和不实施任何防治措施的空白对照进行综合评价.对3种防治措施的综合效益和综合成本进行计算和排序,作为选择豚草防治措施的准则.结果表明:豚草生物防治所获得的综合效益最高,综合成本最低;空白对照的综合效益最低,综合成本最高;化学防治的综合效益和综合成本居中.豚草生物防治效益成本比最高,说明其是一种最为理想的防治措施,值得推广应用.  相似文献   

17.

1. 1. The application method of fuzzy control to air conditioning environment is shown taking home and railcar air conditioners as an example.

2. 2. The control system developed by us includes the capacity control as the basic application example, the control to determine a set temperature, and that to correct automatically the set temperature.

Author Keywords: Fuzzy control; environmental control; home air conditioners; railcar air conditioners; temperature control; airflow control; energy saving  相似文献   


18.
Long-term studies on the economic impact of ticks on Sanga cattle in Zambia   总被引:1,自引:0,他引:1  
Three different tick control policies were tested in groups of traditionally managed Sanga cattle in the Central Province of Zambia over a period of 3 years. One group was given strategic tick control using 12 pyrethroid acaricide spray applications between the onset and the end of the wet season (October to March). The productivity of this herd was compared with that of a group with no tick control and a group under an intensive tick control regimen of spraying every week in the wet season and every 2 weeks in the dry season (36 applications per year). The highest output was associated with intensive tick control, followed by strategic control and then no tick control policies. However, when the costs of tick control were taken into account, the strategic tick control policy produced the best economic result, followed by the intensive and then the no tick control policies. Neither the strategic nor the intensive tick control policy was sufficient to prevent the transmission of East Coast fever (ECF) infection when this disease was introduced to the area.  相似文献   

19.
Elusive control     
The concept of a single rate-limiting step was proven to be too simplistic for understanding control and regulation of metabolism. Consequently, searches have identified relatively few steps with high control. Here we review a number of such searches and indicate what mechanisms may be responsible for this elusiveness of control. It turns out that this elusiveness of control has itself led to increased understanding of the roles played in metabolic control and regulation of such diverse factors as distributiveness of control, condition dependence, enzyme elasticity, homeostasis, control hierarchies, the input into a pathway, coenzyme sequestration, and redundancy and diversity of control function.  相似文献   

20.
System identification techniques applied to experimental human-in-the-loop data provide an objective test of three alternative control-theoretical models of the human control system: non-predictive control, predictive control, and intermittent predictive control. A two-stage approach to the identification of a single-input single-output control system is used: first, the closed-loop frequency response is derived using the periodic property of the experimental data, followed by the fitting of a parametric model. While this approach is well-established for non-predictive and predictive control, it is here used for the first time with intermittent predictive control. This technique is applied to data from experiments with human volunteers who use one of two control strategies, focusing either on position or on velocity, to manually control a virtual, unstable load which requires sustained feedback to maintain position or low velocity. The results show firstly that the non-predictive controller does not fit the data as well as the other two models, and secondly that the predictive and intermittent predictive controllers provide equally good models which cannot be distinguished using this approach. Importantly, the second observation implies that sustained visual manual control is compatible with intermittent control, and that previous results suggesting a continuous control model for the human control system do not rule out intermittent control as an alternative hypothesis. Thirdly, the parameters identified reflect the control strategy adopted by the human controller.  相似文献   

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