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61.
The family Embolemidae Westwood, 1833 is recorded for the first time in Korea, based on a species Embolemus ruddii Westwood. A diagnosis of this species complemented by digital images are provided. 相似文献
62.
Muhammad A. KHAN Waseem AKRAM Muhammad ASHFAQ Hafiz A. A. KHAN Yeon K. KIM Jong-Jin LEE 《Entomological Research》2010,40(6):285-289
Silkworm rearing has been an income source for small-holding farmers in Pakistan. Over the years efforts have been made to improve silkworm quality and quantity and thus develop better prospects for increasing yield and income. Mulberry leaves Morus alba L. in a series of experiments have been supplemented with various nutrients in different doses and combinations. Relative success has been achieved in this context. In our present experiments on silkworm Bombyx mori L., we fed the larvae on mulberry leaves supplemented with different doses of N (0.2%), P (0.1%), K (0.3%) and Ca (0.1%) at 26 ± 3°C with 65 ± 5% relative humidity. The results showed better outputs in terms of food consumption (72.55 g/10 larvae), coefficient of utilization (76.45%), body weight (70.07 g/10 larvae) and body length (8.56 cm/larvae) than where simple mulberry leaves were offered. Our net gains with these production parameters have been in terms of heavier cocoons with and without pupa (2.25 and 0.69 g/cocoon), respectively. 相似文献
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64.
Chemosensory Adaptation to Lysozyme and GTP Involves Independently Regulated Receptors in Tetrahymena thermophila 总被引:1,自引:0,他引:1
HEATHER G. KURUVILLA MARK Y. KIM TODD M. HENNESSEY 《The Journal of eukaryotic microbiology》1997,44(3):263-268
ABSTRACT. Chemosensory adaptation is seen in Tetrahymena thermophila following prolonged exposure (ten minutes) to micromolar concentrations of the chemorepellents lysozyme or guanosine triphosphate (GTP). Since these cells initially show repeated backward swimming episodes (avoidance reactions) in these repellents, behavioral adaptation is seen as a decrease in this repellent-induced behavior. The time course of this behavioral adaptation is paralleled by decreases in the extents of surface binding of either [32 P]GTP or [3 H]lysozyme in vivo. Scatchard plot analyses of repellent binding in adapted cells suggests the behavioral adaptation is due to a dramatic decrease in the number of surface binding sites, as represented by decreased Bmax values. The estimated KD values for nonadapted cells are 6.6 μM and 8.4 μM for lysozyme and GTP binding, respectively. Behavioral adaptation and decreased surface receptor binding are specific for each repellent. The GTP adapted cells (20 μM for ten minutes) still respond behaviorally to 50 μM lysozyme and bind [3 H]lysozyme normally. Lysozyme adapted cells (50 μM for ten minutes) still bind [32 P]GTP and respond behaviorally to GTP. All the behavioral and binding changes seen are also reversible (deadaptation). Neomycin was shown to be a competitive inhibitor of [3 H]lysozyme binding and lysozyme-induced avoidance reactions, but it had no effect on either [32 P]GTP binding or GTP-induced or avoidance reactions. These results are consistent with the hypothesis that there are two separate repellent receptors, one for GTP and the other for lysozyme, that are independently downregulated during adaptation to cause specific receptor desensitization and consequent behavioral adaptation. 相似文献
65.
We have conducted three hatchery-scale experiments designedto examine the actions and interactions of cortisoi and thyroidhormones in the development of a larval marine fish. Survivalamong controls varied significantly between the 3 replicateexperiments. The threadfin (Polydactylus sexfilis) consistentlyresponds to 1 hr posthatch immersion in a combination of triiodothyronineand cortisoi (T3 + F) with accelerated gut development and increasedsurvival compared with untreated controls (C). Survival amonglarvae treated with T3 or F separately was significantly improvedover controls in one of the three experiments. The frequencyof spinal deformities was reduced by cortisoi treatment, aloneor in combination with T3. Growth did not vary with treatment,except that variance in larval length was reduced in (T3 + F)vs. C in all 3 experiments. A hormoneinduced increase in uniformitycould lead to reduced cannibalism, which is a problem in theculture of threadnns. These results suggest interactive hormonalregulation of developmental processes, working within the contextof other biological variables 相似文献
66.
ABSTRACT Not only were used Random amplified polymorphismic DNA(RAPD) markers as input for an analysis of molecular variance (AMOVA) and cluster analysis to describe the population genetic structure, but also morphometric analysis of Formica japonica in Korea in order to investigate the relationships between local populations according to altitude. The ten populations of F. japonica in Korea did not showed any relationships according to altitude in morphological analysis, while they showed distinct relationship in RAPD analysis. It was noticed that they were clearly separated as four groups according to altitude. The first was Jirisan-Gachilbong- Gyebangsan population, the second Iksansi-Odongdo, the third Deukyusan-Hallasan, the fourth Siheungsi- Seonamsa-Jinjusi. The first group was high mountainous, the second flat and low altitude, the third high mountainous, and the fourth flat and low altitude. They occur from low altitude to comparative high altitude 1,400 m in Korea. Actually, it was found that the relationships of 10 local populations of Korean Formica japonica were not related to morphological evolution, but related to molecular evolutionary data evolved from RAPD analysis. 相似文献
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68.
ABSTRACT The phytogeny of Formica ants in Korea was carried out using RAPD. Analyzing RAPD marker, the similarity degrees between species were estimated, and they were compared with the results from the measuring values of thirteen morphological characters. Morphological analysis showed as follows: all the five species were grouped with 72% or more similarity. Out-group, Camponotus was independently isolated. F. lemani and F. Candida, F. yessensis and F.japonica were grouped in a very tight cluster with 97% or more similarity, while F. sanguinea+F. yessensis and F.japonica were grouped with 88%. On the other hand, RAPD analysis showed as followes: F. sanguinea, F. yessensis were grouped at the level of 97% similarity, F. lemani and, F. Candida were also grouped with 97%. Both two groups were again grouped with 85% or more. This group and F.japonica were grouped with 72% similarity. In RAPD the lowest similarity was 72% in the five species of Formica. The positional homology of amplified fragments was identified by Southern hybridiztion of RAPD fragments. As a result, F. sanguinea and F. yessensis showed 97% degree of similarity, and also F. lemani and F. Candida showed 97%. F.japonica and above four species showed 72%. The level of similarity of F.japonica against the other four species was lower than those of four other species. 相似文献
69.
KIM VAN DER LINDE JAN G. SEVENSTER 《Biological journal of the Linnean Society. Linnean Society of London》2006,87(1):115-125
The ecological trade-off between developmental time and starvation resistance, acting in a heterogeneous environment, can promote the coexistence of competing species. Heterogeneity results from variation in the vegetation that influences both abiotic (e.g. temperature, humidity) and biotic (e.g. fruit availability during the year) aspects of the environment. In this study, we investigated whether differences between collection sites have led to local differentiation of the two life-history traits underlying the coexistence model: developmental time and starvation resistance. Drosophila were collected from four collection sites, ranging from grassland to secondary forest, along a transect of 15 km. The microclimatic and vegetation differences among these collection sites were considerable. For developmental time, different species showed similar genetic responses to the (habitat) differences between the different collection sites. The shortest developmental times were found in the secondary forest populations and the agricultural area populations, the longest in the grassland populations, and the forest edge populations were intermediate. However, there was no correlation between the habitat ranking based on disturbance and canopy cover, and the ranking of the developmental times. Furthermore, the data did not confirm the generality of the positive correlation between developmental time and starvation underlying the coexistence model. © 2006 The Linnean Society of London, Biological Journal of the Linnean Society, 2006, 87 , 115–125. 相似文献
70.
We reviewed the family Lycidae in Korea. The Korean Lycidae was recorded to fourteen species under eight genera until now. However, the taxonomy of Korean species was conducted without comparative analysis. We revised the Korean Lycidae to eleven species under seven genera of two subfamilies. Also, we provided the key to subfamilies, gernera, and species including illustrations of pronotum and aedeagus, the photos of adult habitus. 相似文献