首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   49篇
  免费   1篇
  国内免费   1篇
  2021年   1篇
  2017年   1篇
  2016年   1篇
  2015年   1篇
  2014年   1篇
  2006年   1篇
  2005年   1篇
  2003年   1篇
  2002年   1篇
  2001年   1篇
  1997年   1篇
  1996年   1篇
  1994年   1篇
  1986年   2篇
  1985年   4篇
  1983年   1篇
  1982年   2篇
  1981年   1篇
  1980年   3篇
  1979年   1篇
  1978年   1篇
  1977年   1篇
  1976年   4篇
  1975年   3篇
  1973年   3篇
  1972年   1篇
  1970年   2篇
  1968年   2篇
  1967年   2篇
  1966年   2篇
  1963年   1篇
  1962年   1篇
  1952年   1篇
排序方式: 共有51条查询结果,搜索用时 900 毫秒
11.
The study of the population dynamics of the celery leaf-miner, Philophylla heraclei, must take into account the fact that the host-plant is not present permanently and that it develops between the two annual generations of the insect. This development affects in particular the quality and quantity of the leaves fed upon by the mining larvae. It is possible to know the numerical change of the populations from one annual generation to the next (bivoltine insect) and from one year to the next by counting the populations in the various larval instars, responsible for the injury caused to celery. An accurate method of counting of larval numbers, taking into account their change parallel with that of the host-plant, is described in this text. It makes it possible to know with accuracy the duration and importance of the infestations in relation to external factors and to factors inherent to the host-plant itself. Certain traits of larval behaviour, particularly the transfer of a larva from its original mine to a secondary mine as a result of food shortage can thus be established and estimated quantitatively.  相似文献   
12.
13.
The immatures stages of 8 of the 11 genera (Amastris Stål, Bajulata Ball, Erosne Stål, Harmonides Kirkaldy, Idioderma Van Duzee, Neotynelia Creão-Duarte & Sakakibara, Tynelia Stål, and Vanduzea Goding) of the tribe Amastrini are described for the first time along with brief diagnoses of Membracidae and the subfamily Smiliinae. A key to genera and notes on biology are provided. Multiple species of most genera are illustrated. Based on its distinct nymphal morphology, Vanduzea laeta nolina Ball is elevated to specific rank as Vanduzea nolina stat. n., and Bajulata, despite the superficial similarity of its adults to those of Vanduzea, is confirmed as warranting generic rank based on its unique nymphal morphology. Colombia is a new country record for Tynelia.  相似文献   
14.
The final moult in cicadas marks a major transition in lifestyle and is a behaviour that makes the cicada vulnerable to predation. Consequently, emergence times are short and, we predict, therefore the rate of energy consumption would be high. Hence, we measured the energetic cost of emergence in Cyclochila australasiae (green grocer) and Abricta curvicosta (floury baker) cicadas during the final moult from nymph to adult cicada. Maximum energy expended whilst emerging was compared between the sexes and species. Even though C. australasiae take longer to emerge than A. curvicosta, the mass-specific cost of emergence is not different between the two species (C. australasiae: 11.34+/-2.55 J g(-1); A. curvicosta: 12.91+/-1.90 J g(-1)). The mass-specific metabolic rates of fully emerged adults of both species are approximately twice those of the nymphs and the maximum metabolic rate during emergence is about 1.5 times higher than the resting metabolic rate of emerged adults. Emergence times, as indicated by rates of oxygen consumption, are longer than expected and probably reflect limitations in the oxygen capacity of the cicadas during moulting.  相似文献   
15.
根据蜉蝣稚虫的生活环境,可简单地将其分为静水区种类和流水区种类。静水区种类可生活于水体中、底质表面和底质中三种不同的小栖境,流水区种类可生活于水体中、底质表面和底质缝隙间三类小栖境。形态各异的不同种类蜉蝣稚虫生活在不同的小环境,表明种类演化和形态变化与环境有密切关系。  相似文献   
16.
Oviposition rates and related behaviours were quantified for Lariophagus distinguendusFörster attacking Calosobruchus chinensis (L.) and C. maculatus (F.). Oviposition rates varied with parasitoid age; parasitoids aged 1–7 days laid approximately twice as many eggs per day as those aged 8–14 days. Similar differences were noted in search rates and handling times; younger parasitoids had higher attack rates and lower handling times than older parasitoids. Search rates and handling times also varied with the host stage available for attack. Search rates were higher and handling times were lower on larger stages. The results are discussed with reference to their impact on the dynamical behavior of insect parasitoid-host populations.  相似文献   
17.
18.
Summary Six survival curves were drawn (Fig. 1) from a survey over two generations of the population ofDendro'imus spectabi'is Butler at three different places in the Tokyo University Forest in Aichi during the years from 1957 to 1959. The counting of insect number was done at one month interval except during the winter season. Any apparent mortality expressed as percentage decrease was not related in this survey with the density of insect population at the beginning of each interval. Considering of the magnitude and the variability of each apparent mortality, there were three critical periods of heavy decrease in the generation decline, they were; 1) September to October when newly born larvae were dispersing, 2) December to March when the third instar larvae were overwintering, and 3) August to September for the period of fully grown larvae and pupae.  相似文献   
19.
20.

Contributions from the Entomological Laboratory, Kyoto University, No. 203.  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号