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261.
BERNARD J. CRESPI 《Ecological Entomology》1986,11(2):119-130
ABSTRACT.
- 1 Hoplothrips pedicularius (Haliday) (Thysanoptera: Phlaeothripidae), a tubuliferan thrips in which males possess greatly enlarged forelegs, lives in colonies on Stereum fungus.
- 2 Females oviposit onto communal egg masses, and males fight by grasping and stabbing with their forelegs in territorial defence of oviposition areas. Prolonged escalated fights occur between males who are of similar size.
- 3 Larger males usually win fights and become dominant at the oviposition area. Dominant males secure 80% of matings, and mate most frequently during oviposition periods, with an ovipositing female.
- 4 Smaller, subordinate males avoid fights and attempt to 'sneak’copulations. However, they occasionally challenge the dominant male. Challenges tend to follow copulations by the subordinate male and occur more frequently between males who are of similar size.
- 5 Subordinate males who eventually leave the oviposition area are larger than those who remain, have frequently challenged the dominant male, and have more frequently been stabbed.
- 6 Sexual dimorphism in thrips is associated with gregariousness, claustral habitats, female-biased sex ratios, and male winglessness. In thrips genera in which males exhibit foreleg armature, males are larger relative to females. The ecological circumstances promoting sexual dimorphism and male fighting in spatially-structured populations are discussed.
262.
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264.
Rachel Han Jungyoung Tiffany Shin Jin Kim Yong Seok Choi Young Wook Kim 《Entomological Research》2017,47(3):141-151
The purpose of this paper is to provide an overview of the edible insect industry in South Korea and present suggestions for future pricing and promotion strategies. In the first section of this paper, this study outlines the current status and challenges of the edible insect industry in the food market, the material market, the animal feed market, and the medicinal market. The second section of this paper suggests different pricing and promotion strategies for each market segment. This study describes how the consideration of personal traits, information framing, and increasing familiarity can enhance consumer consumption of insect‐based foods. 相似文献
265.
《Fungal Ecology》2017
We asked if exotic Pinus elliotti seedlings can survive and form ectomycorrhizas at higher elevations and long distances from their current range, and which ECM partners disperse to these soils. We selected three plots at four grassland sites along an altitudinal gradient (900, 1600, 2200, and 2700 m asl) established at c. 110, 3000, 6000, and 9000 m from the closest pine plantation, respectively. We combined field experiments with glasshouse assays to assess survival and ECM fungi in roots and soils. A pine plantation close to the lowest site was also selected for DNA metabarcoding of soils. Pine seedlings survived at all altitudes but not all formed mycorrhizas. They formed mycorrhizas with Suillus granulatus at 900, 1600, and 2200 m asl (i.e. up to 6000 m from the closest pine plantation), and with Rhizopogon pseudoroseolus and Thelephora terrestris at lower altitudes and distances. Twelve ECM fungal OTUs were found in grasslands and 34 were detected in the pine plantation. Although richness and abundance of ECM fungi decreased with increasing distance from the pine plantation, there was at least one non-native ECM fungal species present in each sampling site, even at 2700 masl and 9000 m distance from the closest plantation. This study provides evidence that the availability of suitable fungal symbionts might constrain but not hinder the expansion of a pine species over wide distances and altitudinal zones even in areas with no native ECM fungi. 相似文献
266.
New aspects of grassland recovery in old‐fields revealed by trait‐based analyses of perennial‐crop‐mediated succession 下载免费PDF全文
András Kelemen Béla Tóthmérész Orsolya Valkó Tamás Miglécz Balázs Deák Péter Török 《Ecology and evolution》2017,7(7):2432-2440
Classical old‐field succession studies focused on vegetation changes after the abandonment of annual croplands or on succession after the elimination of cultivated crops. Perennial‐crop‐mediated succession, where fields are initially covered by perennial crops, reveals alternative aspects of old‐field succession theories. We tested the validity of classical theories of old‐field succession for perennial‐crop‐mediated succession. We formulated the following hypotheses: (1) functional diversity increases with increasing field age; (2) resource acquisition versus conservation trade‐off shifts toward conservation at community level during the succession; (3) the importance of spatial and temporal seed dispersal decreases during the succession; and (4) competitiveness and stress‐tolerance increases and ruderality decreases at community level during the succession. We studied functional diversity, trait distributions and plant strategies in differently aged old‐fields using chronosequence method. We found increasing functional richness and functional divergence, but also unchanged or decreasing functional evenness. We detected a shift from resource acquisition to resource conservation strategy of communities during the succession. The role of spatial and temporal seed dispersal was found to be important not only at the initial but also at latter successional stages. We found an increasing stress‐tolerance and a decreasing ruderality during succession, while the competitiveness remained unchanged at the community level. Despite the markedly different starting conditions, we found that classical and perennial‐crop‐mediated old‐field successions have some similarities regarding the changes of functional diversity, resource acquisition versus conservation trade‐off, and seed dispersal strategies. However, we revealed also the subsequent differences. The competitive character of communities remained stable during the succession; hence, the initial stages of perennial‐crop‐mediated succession can be similar to the middle stages of classical old‐field succession. Moreover, the occupied functional niche space and differentiation were larger in the older stages, but resources were not effectively utilized within this space, suggesting that the stabilization of the vegetation requires more time. 相似文献
267.
The innate immune system utilizes pattern recognition receptors cyclic GMP-AMP synthase(cGAS)to sense cytosolic double-stranded(ds) DNA and initiate type 1 interferon signaling and autophagy pathway, which collaborate to limit pathogen infections as well as alarm the adaptive immune response. The genomes of herpesviruses are large dsDNA, which represent a major class of pathogen signatures recognized by cellular DNA sensor cGAS. However, to successfully establish the persistent infection, herpesviruses have evolved their viral genes to modulate different aspects of host immune signaling. This review summarizes the evasion strategies of host cGAS DNA sensing pathway by Kaposi's Sarcoma-associated Herpesvirus(KSHV) and their contributions to KSHV life cycles. 相似文献
268.
What best explains vigilance in elk: characteristics of prey, predators, or the environment? 总被引:1,自引:0,他引:1
We quantified the vigilance levels of elk (Cervus elaphus) preyedon by wolves (Canis lupus) in Yellowstone National Park, betweenJanuary and May in 2005 and 2006, and used Akaike's informationcriterion to compare a set of 38 regression models for vigilancelevels. These models combined up to 9 predictor variables of3 types: characteristics of the prey group (herd size and composition),characteristics of the predator (wolf pack size, distance away,and the presence/absence of a kill), and characteristics ofthe local environment (distance to woodland edges, snow depth,and snow cover). The set of models spanned a range of complexityfrom simple univariate models to complex combinations with upto 3 variables of each type. Complex models incorporating thecharacteristics of the wolf pack, the structure of the elk herd,and the environmental conditions had higher information contentthan simple models. Although univariate models of vigilancedetect significant relationships, they have low informationcontent relative to multivariate models. These results showthat elk assesses factors of several types when assessing riskand deciding how much time to allocate to vigilance. In particular,we found that all well-supported models of vigilance includedseveral "prey" variables and several "predator" variables. Thisresult highlights the need to consider information about predatorswhen trying to explain variation in vigilance levels in prey. 相似文献
269.
J.E. Ireson A.H. Gourlay R.J. Holloway W.S. Chatterton S.D. Foster R.M. Kwong 《Biological Control》2008,45(3):460-471
Sericothrips staphylinus was released as a biological control agent for Ulex europaeus in New Zealand and Hawaii following tests on ca. 80 plant species which showed it was narrowly oligophagous. To determine the suitability of S. staphylinus for release in Australia, further host specificity tests were conducted on 38 species and cultivars of Australian plants. These tests confirmed that S. staphylinus would feed only on U. europaeus in Australia and, following formal approval, was released in Tasmania during January 2001. To develop an optimal release strategy for S. staphylinus under Australian conditions, a field trial based on an earlier New Zealand study was conducted by replicating releases of 10, 30, 90, 270 and 810 adults. Results showed that population growth, reproduction rate and the number of S. staphylinus recovered 14 months after release can be non-linear functions of release size and establishment could be achieved with as few as 10 thrips. As S. staphylinus is easily cultured ca. 250 thrips were chosen as the minimum number for release because, based on a negative binomial model, this release size produced close to the maximum population growth. Surveys in early 2007 recovered S. staphylinus from 80% of 30 sites in Tasmania, the post release period ranging from 1 to 6 years. However, densities were low (<1 thrips/cm of tip growth) with no evidence of visible plant damage. The maximum dispersal range was 180–250 m after 38 months. At all the other sites, dispersal was estimated at less than 120 m. It is possible that S. staphylinus populations are still in the lag phase of their establishment before starting to increase rapidly and disperse. However, the survey results support a recent Tasmanian study which indicated that S. staphylinus is a sedentary, latent species characterised by steady densities and low levels of damage to its host plant. Its efficacy as a biological control agent on gorse may be restricted primarily by ‘bottom up’ effects of plant quality limiting its rate of natural increase and an inability of the thrips to reach large, damaging populations under field conditions. 相似文献
270.
Morales Pedraza J 《Cell and tissue banking》2008,9(4):317-322
The main purpose of the International Atomic Energy Agency (IAEA) Public Awareness Strategies for Tissue Banks is to provide
guidance on organizing and running awareness campaigns, in order to consolidate tissue banking activities. Within the IAEA
Public Awareness Strategies for Tissue Banks, there are two important topics, which need to be singled out due to their importance
for a successful public and professional awareness campaign. These are the selection of the audiences and the organization
of media events within a Communication Strategy. The experience in the field of tissue banking in several countries has shown
that interaction between the public, the professional health care staff, the media and the tissue bank personnel is essential
if the activities of the banks are to be successful. It must be emphasized however, that any public and professional awareness
strategy will not be successful, unless it is considered as part of an integrated system that is adopted by the concerned
Government. 相似文献