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101.
Adults and immatures of Aedes mosquito populations were collected at temperatures between 40 and 44°C (summer), while larvae were collected at 0°C (winter). Major mosquito activities were observed from February to mid-December at various collection sites that yielded high populations of Aedes spp. from May to September, and high populations of Culex spp. and Anopheles spp. from March to September. In June to July, mosquito activity was suspended because the relative humidity was high (70%); a result of the monsoon rains. In August, with temperature ranging from 38 to 42°C, the populations of Culex , Anopheles and Aedes began to increase (36.8, 32.1 and 26.3%, respectively). Population estimates (through standard prototype Centers for Disease Control (CDC) and Biogents (BG)-sentinel) and species composition of Aedes in forest habitats indicated a rapid increase in the populations of Ae. albopictus (52.3%), Ae. aegypti (19.1%) and Ae. vittatus (28.5%) following the rainy season in July. Areas positive for Ae. albopictus had identical population levels and distribution ranges of Ae. vittatus , however, there were no Ae. aegypti in Ae. albopictus areas from August to September. The population level, seasonal distribution, habitat and areas of adult activity marked by global positioning system (GPS) coordinates are being used for reference and for species composition data of Anopheles spp. (2), Culex spp. (10) and Aedes spp. (5) in addition to associated temperature, relative humidity and physico-chemical factors of larval habitat. Global meteorological changes have caused an expansion of the active period, leading to the mosquito's possibility of being a vector of disease increasing, resulting in the spread of dengue fever.  相似文献   
102.
A microsatellite‐enriched library of Job's tears (Coix lacryma‐jobi L. var. Ma‐yuen Stapf) was constructed using a modified biotin–streptavidin capture method. After screening, 17 polymorphic microsatellites were used for diversity analysis among 30 Job's tears accessions. The number of alleles ranged from one to five alleles per locus with an average of 2.8 alleles. Expected heterozygosity (HE) and polymorphism information content (PIC) ranged from 0 to 0.676 and from 0 to 0.666, respectively. The newly developed microsatellite markers are expected to be very valuable tools for evaluation of genetic diversity among large germplasm collection of Job's tears present in our Korean Gene Bank.  相似文献   
103.
Assessing the relative role of evolutionary processes on genetic diversity is critical for understanding species response to climatic change. However, many processes, independent of climate, can lead to the same genetic pattern. Because effective population size and gene flow are affected directly by abundance and dispersal, population ecology has the potential to profoundly influence patterns of genetic variation over microevolutionary timescales. Here, we use aDNA data and simulations to explore the influence of population ecology and Holocene climate change on genetic diversity of the Uinta ground squirrel (Spermophilus armatus). We examined phylochronology from three modern and two ancient populations spanning the climate transitions of the last 3000 years. Population genetic analyses based on summary statistics suggest that changes in genetic diversity and structure coincided with the Medieval Warm Period (MWP), c. 1000 years ago. Serial coalescent simulations allowed us to move beyond correlation with climate to statistically compare the likelihoods of alternative population histories given the observed data. The data best fit source–sink models that include large, mid‐elevation populations that exchange many migrants and small populations at the elevational extremes. While the MWP is likely to have reduced genetic diversity, our model‐testing approach revealed that MWP‐driven changes in genetic structure were not better supported for the range of models explored. Our results point to the importance of species ecology in understanding responses to climate, and showcase the use of ancient genetic data and simulation‐based inference for unraveling the relative roles of microevolutionary processes.  相似文献   
104.
ABSTRACT Eight species of the Stenopelmatoidea (Orthoptera: Ensifera) including two newly recorded Nippancistroger testaceus (Matsumura et Shiraki) and Anoplophilus acuticercus Karny are recognized in Korean fauna. Paratachycines (Hemitachycines) uenoi (Yamasaki) is proposed for junior synonym of Paratachycines (Hemitachycines) baldyrevi (Uvarov). The keys to species, characteristic figures and diagnoses for the newly recorded species are presented.  相似文献   
105.
ABSTRACT Five species of the tribe Copiphorini (Orthoptera, Tettigoniidae, Conocephalinae) including a newly recorded species Xestaphrys javanicus Redtenbacher are recognized in Korean fauna. The key to species, characteristic figures, and diagnosis for the newly recorded species are presented.  相似文献   
106.
107.
ABSTRACT A new insect pathogenic fungi, Paecilomyces licacinus HY-4 that was isolated from soil sample, showed biological activity to Chestnut Brown Chafer, pest of golf course. The culture condition for the fungi P. lilacinus HY-4 was optimized through statistical approach for the mass production. According th the bioassay on the pest, the insecticidal activity reached up to 30%, and positive factor for the production of the fungi was zeolite with 97.5% of significance.  相似文献   
108.
SUMMARY. 1. During the summer of 1987 we conducted an acidification experiment using large enclosure at Emerald Lake, a dilute, high-elevation lake in the Sierra Nevada, California, U.S.A. The experiment was designed to examine the effects of acidification on the zooplankton and zoobenthos assemblages of Sierran lakes.
2. Treatments consisted of a control (pH 6.3) and pH levels of 5.8, 5.4, 5.3, 5.0 and 4.7; each treatment was run in triplicate. The experiment lasted 35 days.
3. The zooplankton assemblage was sensitive to acidification. Daphnia rosea Sars emend. Richard and Diaptomns signicauda Lilljeborg decreased in abundance below pH 5.5–5.8, and virtually disappeared below pH 5.0. Bosmina longirostris (Müller) and Keratella taurocephala Ahlstrom became more abundant with decreasing pH. although B. longirostris was rare in the pH 4.7 treatment. These species might serve as reliable indicators of early acidification in lakes such as Emerald Lake.
4. The elimination of D. rosea in acidified treatments probably allowed the more acid-tolerant taxa to increase in abundance because interspecific competition was reduced. Even slight acidification can therefore alter the structure of the zooplankton assemblage.
5. In contrast to the zooplankton, there was no evidence that the zoobenthos in the enclosures was affected by acidification.  相似文献   
109.
For the triangle, duo‐trio, same‐different and 2‐AFC methods, using a model system, mean d′ values for the same subjects, discriminating between the same taste stimuli, were not significantly different. This confirmed the postulated cognitive strategies used for these methods in their respective Thurstonian/signal detection models. Introduction of perceptual variance as a result of the effects of sequences of tasting within a test, forgetting stimulus perceptions and τcriterion variation resulted in the 2‐AFC eliciting a significantly higher d′ than the other three methods. Yet, after a warm‐up procedure, which not only significantly increased values of d′ for all methods but also aligned subjects' τcriteria, the same‐different test had a d′ comparable to that of the 2‐AFC, while both d′ values were significantly higher than those of the triangle and duo‐trio. This suggested that effects of memory were more important those of sequence of tasting.  相似文献   
110.
Abstract. Cuticular resistance to water vapour diffusion is an important aspect of thermocouple psychrometry and may introduce significant error in the measurement of leaf water potential (Ψ). The effect of the citrus (Citrus mitis Blanco) leaf cuticle on water vapour movement was studied using the times required for vapour pressure equilibration during thermocouple psychrometric measurement of Ψ. Cuticular abrasion with various carborundum powders was used to reduce the diffusive resistance of both the adaxial and abaxial leaf surfaces, and the extent of the disruption to the leaf was investigated with light and electron microscopy. Cuticular abrasion resulted in reduced equilibration times due to decreased cuticular resistance and greater water vapour movement between the leaf and the psychrometer chamber. Equilibration times were reduced from over 5 h in the unabraded control leaves to 1 h with cuticle abrasion. This was associated with the decrease in diffusive resistance with cuticular abrasion from over 55 s cm?1 to less than 8 s cm?1 for both the adaxial and abaxial leaf surfaces. Scanning electron micrographs of the abraded leaf tissue revealed considerable disruption of the stomatal ledge and of the guard cells, surface smoothing and displacement of waxes into the stomatal aperture, and damage to veins. Observations with the transmission electron microscope revealed frequent disruption of epidermal cell walls, and damage to both the cytoplasmic and vacuolar membranes.  相似文献   
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