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A new oxazole (1) was obtained from Chinese insect medicine Aspongopus chinensis, along with three known N-acetyldopamine derivatives (2-4). Their structures were determined on the basis of NMR and ESI-MS analyses. The possible biosynthetic pathways of the isolated compounds are discussed. Cytotoxicities of those compounds against 10 selected cancer cells were measured in vitro.  相似文献   
3.
崔建新 《安徽农业科学》2008,36(12):5001-5003
分析比较了河南半翅目蝽科昆虫的世界动物区系和我国动物区在属级阶元的构成,发现河南蝽科昆虫具有显著的东洋区系性质,在我国动物区系亚区水平上以华中区系和西南区系成分为主。  相似文献   
4.
以线粒体16S rDNA基因作为分子标记,对蝽总科8个科23种昆虫进行了系统发育的分析,并采用最大简约法、最大似然法和邻接法构建了分子系统树。结果表明:利用16S rDNA分子研究蝽总科的系统发育关系是适合的,能够重建蝽总科的单系性;土蝽科的位置不稳定,在蝽总科各科进化过程中处于中间位置;龟蝽科与蝽科在MP树和ML树中都形成姊妹群关系,在NJ树中2个科的亲缘关系也比较近;异蝽科是最早分支出来的,表明异蝽科是所研究类群中最为原始的类群。本研究从分子水平上支持了将荔蝽亚科、盾蝽亚科和兜蝽亚科从蝽科中分立出来提升为科的观点。  相似文献   
5.
记述我国蝽种二新种:武夷曼蝽的Menidawuyiensissp.nov.、黄斑拟玉蝽Stachyomiaflavo-maculatasp.nov.,对其形态特征作了详细描述,并附有图,与近似种作了比较。  相似文献   
6.
中国益蝽亚科(Asopinae)名录(半翅目:蝽科)   总被引:3,自引:1,他引:2  
林毓鉴  龙骏 《江西植保》2000,23(2):36-39
本文记录中国益蝽亚科昆虫,共计17属53种。  相似文献   
7.
The influence of weather on the population dynamics of Oebalus poecilus, the principal insect pest of rice in South and Central America, is examined. Light trapping was used for one year, but was soon discarded in favour of the more reliable sweep netting which was utilised to monitor populations in fields and non-cropped habitats from autumn 1999 to spring 2002. The results indicate that O. poecilus feeds on alternative host grasses on levées surrounding the rice fields. Adult bugs move into the fields in mid-January and mid-August of each year. In fields there are typically four generations per season, which are approximately four weeks apart. Adults move off the crop in April and October. Data presented here indicate that rainfall is critical to the ‘off-season’ survival of O. poecilus, and high rainfall during April to July and November to January causes increases in O. poecilus populations. This is particularly important given the recent extreme perturbations in the normal bimodal rainfall patterns caused by El Niño and La Niña events. The ability to predict the severity of O. poecilus populations from weekly rainfall data will provide a significant input into the development of IPM programme for O. poecilus.  相似文献   
8.
根据近年来采集标本、查看标本和查阅资料,对昆明市蝽科昆虫进行了统计和区系分析。结果表明,昆明市蝽科昆虫有44属70种(亚种),其中以菜蝽属种类最多,有4种;其次是岱蝽属、二星蝽属、曼蝽属、益蝽属和稻绿蝽属,各有3种(亚种)。蝽科昆虫东洋区特征极显著,仅在东洋区分布就有38种(亚种),占54.3%,但有较多古北区成分,东洋-古北区共有24种,占34.3%,并含有其他区系成分;在中国动物区系中,均在西南区有分布,但与华中区、华南区和青藏区共有成分较多,分别占74.3%、62.9%和47.1%,同时该区域特有成分较多,有9种,占12.9%,其他区也有一定分布。表明昆明市蝽科昆虫具有显著的东洋区特征和本区域特点。  相似文献   
9.
Although the enemy release hypothesis forms the theoretical basis for classical (=importation) biological control of invasive pests, its core assumptions are not always examined. This could contribute to unrealistic expectations for some biological control programs. In this paper we examine the assumptions that: (i) enemy release has contributed to the invasive nature of four exotic pentatomids in North America; and (ii) classical biological control with egg parasitoids has been or will be successful in reducing populations of these pests below economically significant levels. First, we review the history of biological control programs against invasive stink bugs to highlight the variable and controversial levels of success of introducing egg parasitoids against stink bugs. Then, we use simple stage‐structured matrix models to demonstrate that it may be easy to overestimate the contribution of egg parasitism alone to a reduction in stink bug population growth. Finally, we discuss what realistic expectations might be for success of biological control against invasive stink bugs using egg parasitoids in the context of integrated pest management programs. © 2020 Her Majesty the Queen in Right of Canada Pest Management Science © 2020 Society of Chemical Industry  相似文献   
10.
Abstract

Cohorts of newly laid egg masses of two pod‐sucking bugs, Nezara viridula and Piezodorus hybneri (Hemiptera: Pentatomidae), were exposed to naturally occurring predators and parasitoids on soybean in unsprayed fields at four sites in Northern Sumatra. The fate of the young stages was recorded until the late first instar, before the nymphs start to disperse and feed. Partial life tables showed that mortality of N. viridula until the late first instar was 50–87%, of which 18–65% occurred during the egg stage and was mainly caused by predation; 2–26% of the eggs died of parasitism. P. hybneri which was present at only two sites, showed a 73–89% mortality until the late first instar, of which 69–85% was during the egg stage and, again, mainly caused by predation; 15–24% of the eggs died of parasitism. To evaluate the role of individual egg predator species in the field, we conducted hourly observations of exposed egg masses of the two pests. Dolichoderus sp., Solenopsis geminata (Hymenoptera: Formicidae), Paederus sp. (Coleoptera: Staphylinidae) and several gryllids (Orthoptera) were most commonly encountered feeding on the eggs. An index of ‘predation pressure”; was calculated from the densities of predators in the field and from an estimate of their attack rate based on field observations of predator feeding. Two sites with low predator pressures had low predation rates, while the two sites with high predation pressures had considerably higher predation rates. The implications of the findings for IPM training in soybean are discussed.  相似文献   
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