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61.
62.
Bhrenno M. Trad Rogerio Silvestre Tiago H. Auko Vinicius M. Lopez Eduardo F. dos Santos 《Revista Brasileira de Entomologia》2018,62(4):253-256
We register for first time the occurrence of Epipompilus tucumanus Evans, 1967 in Brazil, and record the spider Ariadna boliviana Simon, 1907 as its host. The observations were made in the National Park of Chapada dos Guimarães, Mato Grosso, Brazil. The prey carriage mechanism is described for first time for this genus, and we provide a video showing this behavior. 相似文献
63.
Agricultural landscapes rich in natural and semi-natural habitats promote biodiversity and important ecosystem services for crops such as pest control. However, semi-natural habitats may fail to deliver these services if agricultural pests are disconnected from the available pool of natural enemies, as may be the case with invasive species. This study aimed to provide insights into the relationship between landscape complexity and the abundance of the recently established invasive pest species Drosophila suzukii and a group of natural enemies (parasitoid wasps), which contain species that parasitize D. suzukii in native and invaded ecosystems. The importance of landscape complexity was examined at two spatial scales. At the field scale, the response to introduction of wildflower strips was analysed, while the relationship with forest cover was assessed at the landscape scale. Half of the surveys were done next to blueberry crops (Vaccinium corymbosum), the other half was done in landscapes without fruit crops to examine effects of D. suzukii host presence. As expected, the number of observed parasitoid wasps increased with amount of forest surrounding the blueberry fields, but the number of D. suzukii individuals likewise increased with forest cover. Establishment of wildflower strips did not significantly affect the abundance of D. suzukii or parasitoid wasps and insect phenology was similar in landscapes with and without blueberry crops. This suggests that D. suzukii is enhanced by landscape complexity and is largely unlinked from the species group that, in its native range, hosts key natural enemies. Although management practices that rely on enhancing natural enemies through habitat manipulations can contribute to the long-term stability of agroecosystems and to control agricultural pests, other control measures may still be necessary in the short term to counteract the benefits obtained by D. suzukii from natural habitats. 相似文献
64.
The genus Balcha Walker (Eupelmidae) is recorded for the first time in South Korea, with one newly described species and one newly recorded species. Both sexes of Balcha opaca Fusu sp. n. are described, and the presumed male of B. dictyota Gibson is described for the first time. The newly described species is peculiar in having a comparatively darker and less shiny mesoscutum. In other species of the genus the mesoscutum has brilliant metallic colours that contrast with dorsal dark bands along areas of much finer sculpture. 相似文献
65.
Lien T.P. Nguyen Anh D. Nguyen Trang T.P. Nguyen Adrien Perrard James M. Carpenter 《Journal of Asia》2018,21(2):638-644
This study provides the first molecular phylogeny of the social wasp subgenus Polistella (Hymenoptera: Vespidae: Polistes) from Vietnam. Fragments of the mitochondrial COI and 16S rRNA genes were used to reconstruct the phylogenetic trees among 38 Polistes species plus two out-group species (Vespa soror du Buysson and Ropalidia fasciata (Fabricius)). Our results support the existence of several species-groups, including two that are congruent with the previous stigma and Stenopolistes groups defined on the basis of morphology. Moreover, we recovered a clade including the stigma group and the two species P. humilis and P. variabilis that was sister to all other species of Polistella. However, the results also challenged the definition of other groups of Polistella based on morphological data, as well as the definition of two species: P. brunus and P. affinis. This first study calls for further analyses including morphological characters to clarify the taxonomy and the classification of the group. 相似文献
66.
Malcolm G. Keeping 《Journal of Insect Behavior》1997,10(2):265-278
Colonies ofBelonogaster petiolata in Gauteng (South Africa) produced reproductive offspring (gynes and males) in late January and early February of each nesting
season; their appearance was associated with a decline in worker and brood numbers. Brood decline could commence in the presence
of a dominant, reproductively active queen, and loss or removal of the queen was not followed directly by cessation of nest
growth and brood care. An older worker usually took over the α-position in queenless colonies. Several factors appear to contribute
to brood decline and, ultimately, termination of the colony cycle in this species. These include (1) cessation of the supply
of solid food to colonies (and particularly their larvae) during the reproductive phase, (2) a decrease in the worker/larva
ratio during the latter phase due to the progressive loss of workers, (3) increasing number of gynes and males, and (4) an
adult priority over food reception from foragers. 相似文献
67.
With a view toward describing behavioral variability among individuals of the primitively eusocial speciesBelonogaster juncea juncea, we recorded the time-activity budget spent on five behavioral categories (foraging, building, feeding, inactivity, and reproduction)
by 52 individuals belonging to four postemergence colonies. A principal-components analysis coupled with a hierarchical cluster
analysis enabled us to discern four behavioral roles. The reproductive role is reserved to one individual (functional monogyny)
and the workers’ role is differentiated into foragers, builders, and guards. The foragers are females that spend the most
time (82.6% of their time) foraging, supplying the nest with prey load and liquid matter. The builders are individuals (with
41.5% of their time off the nest) that tend to bring pulp into the nest and then undertake building activities. The guards
are those females that spend the most time (79.7% of their time) being inactive on the nest. 相似文献
68.
The phenology and pollination ecology of three native fig species were studied in southeastern Brazil. Populations displayed continual syconia production, with one species showing intra-tree flowering asynchrony. Pollination of the fig flowers was necessary for the development of the syconia; lack of pollination induced abortion of syconia. All three species follow the general pattern of pollination known for figs, but the behavior of the pollinator wasps, Pegoscapus spp., differed in some aspects from those of other neotropical and paleotropical fig wasps, mainly with respect to pollen loading and unloading during pollination. The longevity of Pegoscapus wasps outside the syconium was about two days. 相似文献
69.
Isolation and characterization of microsatellite loci from three cryptic species of Ceratosolen emarginatus 下载免费PDF全文
From an enriched (AG)n/(AC)n library, we developed nine polymorphic microsatellite loci for three cryptic species of the fig‐pollinating wasp Ceratosolen emarginatus. We genotyped one population for each of the three cryptic species across all the nine loci. In total, 204 alleles were detected from the three cryptic species of C. emarginatus. The observed heterozygosity was 0.755 ± 0.034, 0.653 ± 0.030 and 0.603 ± 0.073 in C. emarginatus populations A, B and C, respectively; the expected heterozygosity was 0.850 ± 0.031, 0.724 ± 0.035 and 0.702 ± 0.104, respectively. No linkage disequilibrium was found between any two loci of all three cryptic species. The newly isolated microsatellite markers will be very useful for estimating the genetic variation within and among the cryptic species and for revealing the mechanisms of speciation and inbreeding coexistence hypothesis of the cryptic species. 相似文献
70.