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本文参考了国内外近年来最新研究进展,对分子标记概念和类型作了简要介绍;论述了分子标记技术在植物改良中的主要用途:遗传图谱的构建,基因定位,物种间基因组比较,分子标记辅助育种;较详细地介绍了芸苔属植物在分子标记方面的研究进展。 相似文献
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分子标记技术在蚕学研究中的应用 总被引:3,自引:0,他引:3
介绍了近年来DNA分子标记技术在绢丝昆虫的进化及亲缘关系分析、家蚕品种真实性鉴定、家蚕分子连锁图的构建、基因标记和定位等方面应用的重要进展 ,并展望了家蚕分子标记辅助育种的前景 相似文献
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单核苷酸多态性(single nucleotide polymorphisms,SNPs)主要是指在染色体基因组水平上由于单个核苷酸的变异而引起的DNA序列多态性,包括单碱基的转换或颠换引起的点突变,其中最少出现1种等位基因频率不小于1%,常以双等位基因的形式出现,稳定而可靠。在目前的昆虫基因组研究中,SNPs标记的研究主要集中在果蝇、蚊媒、家蚕等一些模式生物。本文对SNPs标记在昆虫的种类鉴定、遗传图谱构建、种群遗传学、抗药性分子机理等方面进行了综述,最后展望了SNPs在种群遗传、标记辅助选择和生物进化等研究领域中的应用前景。 相似文献
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分子遗传标记技术及其在昆虫科学中的应用 总被引:16,自引:3,他引:16
分子遗传标记是随着聚合酶链式反应 (PCR)和Southern杂交等分子生物学技术的飞速发展而出现的遗传学标记技术 ,它突破了以往形态标记 ,细胞学标记和同工酶标记等表达型标记的局限性 ,在揭示物种的遗传变异性研究中发挥着独特的优势。分子遗传标记目前已出现了几十种 ,可依其涉及的位点和反映的多态性的基础分为多位点分子标记和单位点分子标记 ,多位点分子标记反映核苷酸序列的多态性 ,单位点分子标记反映基因座上等位基因的多态性。本文对一些常用的分子标记技术的特点和它们在昆虫系统进化、昆虫分类、昆虫生态、生物防治和特定基因标记等研究中的应用作了介绍。 相似文献
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We have found that the actin and microtubule cytoskeletons have overlapping, but distinct roles in the morphogenesis of epidermal hairs during Drosophila wing development. The function of both the actin and microtubule cytoskeletons appears to be required for the growth of wing hairs, as treatment of cultured pupal wings with either cytochalasin D or vinblastine was able to slow prehair extension. At higher doses a complete blockage of hair development was seen. The microtubule cytoskeleton is also required for localizing prehair initiation to the distalmost part of the cell. Disruption of the microtubule cytoskeleton resulted in the development of multiple prehairs along the apical cell periphery. The multiple hair cells were a phenocopy of mutations in the inturned group of tissue polarity genes, which are downstream targets of the frizzled signaling/signal transduction pathway. The actin cytoskeleton also plays a role in maintaining prehair integrity during prehair development as treatment of pupal wings with cytochalasin D, which inhibits actin polymerization, led to branched prehairs. This is a phenocopy of mutations in crinkled, and suggests mutations that cause branched hairs will be in genes that encode products that interact with the actin cytoskeleton. 相似文献
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Birds are believed to be one of the principal predators of butterflies. The beak marks (BMs) left on the butterfly wings are useful indices of bird predation. We performed 84 collections in grasslands and woodlands during 2002–2006 in Ito, Shizuoka prefecture, and collected 893 specimens belonging to 48 species. In general, the larger was the body size the higher was the BM rate. There were two peaks in the BM rate and the peaks were higher by 13–14 % in autumn than in spring in both grasslands and woodlands. During 2007 and 2008, capture-mark-recapture surveys were conducted 82 times in a flight path of black swallowtail butterflies (BSBs). A total of 443 BSB were individually marked and released at a site 400 m away from the flight path after examining for BM, degree of wing damage, body size, sex and species. The BM% of BSB ranged from 40 to 46 %, which was the highest among the observed butterflies. The recapture rate was negatively correlated with the BM rate suggesting that the avian predation was strong enough to affect the survival rate of BSB adults. In addition, the BM rate showed a delayed positive response to BSB density in the previous month. Variation in the BM rate was analyzed with a multivariate model; it indicated that month and wing length were significant explanatory variables. In addition, the highest BM rate was observed at an intermediate wing size. These results strongly suggested that variation in the BM rate was caused by variation in avian life history and predator size. All the evidence suggested that an appreciable predation pressure by birds operated on BSB adult populations. 相似文献
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Konjev Desender 《Oecologia》1989,78(4):513-520
Summary The wing-polymorphic ground beetle Pogonus chalceus MARSHAM was subjected to crossbreeding experiments under different laboratory conditions in order to estimate the genetic and environmental contributions to the total phenotypic variance in different morphological traits related to relative wing development and body size. Heritability of relative wing development appears to be strong. Beetle size also seems genetically determined in some cases, but separation of male and female parent contribution invariably shows a maternal effect. These results are tested in a breeding experiment with a high number of progeny from one parental pair, reared at two temperatures and at two levels of food supply. Relative wing development is not influenced by these environmental conditions, as expected, but different temperatures add significant variance to the body size values. The experimental results are used to explain interdemic variation in these morphological traits, as observed in three isolated field populations. The reproductive effort under optimum breeding conditions is higher in macropterous beetles than in beetles with reduced wings, but this could result from their larger body size. Migtion seems to be the most plausible underlying evolutionary mechanism for the observed wing reduction in older populations. 相似文献
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Geiser F Brigham RM 《Journal of comparative physiology. B, Biochemical, systemic, and environmental physiology》2000,170(2):153-162
Previous studies have suggested that Australian long-eared bats (Nyctophilus) differ from northern-hemisphere bats with respect to their thermal physiology and patterns of torpor. To determine whether
this is a general trait of Australian bats, we characterised the temporal organisation of torpor and quantified metabolic
rates and body temperatures of normothermic and torpid Australian bats (Nyctophilus geoffroyi, 7 g and N. gouldi, 10 g) over a range of air temperatures and in different seasons. The basal metabolic rate of normothermic bats was 1.36 ± 0.17 ml g−1 h−1 (N. geoffroyi) and 1.22 ± 0.13 ml g−1 h−1 (N. gouldi), about 65% of that predicted by allometric equations, and the corresponding body temperature was about 36 °C. Below an air
temperature of about 25 °C bats usually remained normothermic for only brief periods and typically entered torpor. Arousal
from torpor usually occurred shortly after the beginning of the dark phase and torpor re-entry occurred almost always during
the dark phase after normothermic periods of only 111 ± 48 min (N. geoffroyi) and 115 ± 66 min (N. gouldi). At air temperatures below 10 °C, bats remained torpid for more than 1 day. Bats that were measured overnight had steady-state
torpor metabolic rates representing only 2.7% (N. geoffroyi) and 4.2% (N. gouldi) of the basal metabolic rate, and their body temperatures fell to minima of 1.4 and 2.3 °C, respectively. In contrast, bats
measured entirely during the day, as in previous studies, had torpor metabolic rates that were up to ten times higher than
those measured overnight. The steady-state torpor metabolic rate of thermoconforming torpid bats showed an exponential relationship
with body temperature (r
2 = 0.94), suggesting that temperature effects are important for reduction of metabolic rate below basal levels. However, the
75% reduction of metabolic rate between basal metabolic rate and torpor metabolic rate at a body temperature of 29.3 °C suggests
that metabolic inhibition also plays an important role. Torpor metabolic rate showed little or no seasonal change. Our study
suggests that Australian Nyctophilus bats have a low basal metabolic rate and that their patterns of torpor are similar to those measured in bats from the northern
hemisphere. The low basal metabolic rate and the high proclivity of these bats for using torpor suggest that they are constrained
by limited energy availability and that heterothermy plays a key role in their natural biology.
Accepted: 22 November 1999 相似文献
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High environmental temperatures pose significant physiological challenges related to energy and water balance for small endotherms. Although there is a growing literature on the effect of high temperatures on birds, comparable data are scarcer for bats. Those data that do exist suggest that roost microsite may predict tolerance of high air temperatures. To examine this possibility further, we quantified the upper limits to heat tolerance and evaporative cooling capacity in three southern African bat species inhabiting the same hot environment but using different roost types (crevice, foliage or cave). We used flow-through respirometry and compared heat tolerance limits (highest air temperature (Ta) tolerated before the onset of severe hyperthermia), body temperature (Tb), evaporative water loss, metabolic rate, and maximum cooling capacity (i.e., evaporative heat loss/metabolic heat production). Heat tolerance limits for the two bats roosting in more exposed sites, Taphozous mauritianus (foliage-roosting) and Eptesicus hottentotus (crevice-roosting), were Ta = ~44 °C and those individuals defended maximum Tb between 41 °C and 43 °C. The heat tolerance limit for the bat roosting in a more buffered site, Rousettus aegyptiacus (cave-roosting), was Ta = ~38 °C with a corresponding Tb of ~38 °C. These interspecific differences, together with a similar trend for higher evaporative cooling efficiency in species occupying warmer roost microsites, add further support to the notion that ecological factors like roost choice may have profound influences on physiological traits related to thermoregulation. 相似文献
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Schmidt-Wellenburg CA Biebach H Daan S Visser GH 《Journal of comparative physiology. B, Biochemical, systemic, and environmental physiology》2007,177(3):327-337
Many bird species steeply increase their body mass prior to migration. These fuel stores are necessary for long flights and
to overcome ecological barriers. The elevated body mass is generally thought to cause higher flight costs. The relationship
between mass and costs has been investigated mostly by interspecific comparison and by aerodynamic modelling. Here, we directly
measured the energy expenditure of Barn Swallows (Hirundo rustica) flying unrestrained and repeatedly for several hours in a wind tunnel with natural variations in body mass. Energy expenditure
during flight (e
f, in W) was found to increase with body mass (m, in g) following the equation e
f = 0.38 × m
0.58. The scaling exponent (0.58) is smaller than assumed in aerodynamic calculations and than observed in most interspecific
allometric comparisons. Wing beat frequency (WBF, in Hz) also scales with body mass (WBF = 2.4 × m
0.38), but at a smaller exponent. Hence there is no linear relationship between e
f and WBF. We propose that spontaneous changes in body mass during endurance flights are accompanied by physiological changes
(such as enhanced oxygen and nutrient supply of the muscles) that are not taken into consideration in standard aerodynamic
calculations, and also do not appear in interspecific comparison. 相似文献
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The effects of larval density on the wing form determination of female tobacco thrips, Frankliniella fusca, were investigated by rearing thrips on leaf disks at 27.5 °C. The developmental period, head width, body length, and forewing length of individuals in each wing morph were determined to assess the relationships among larval density, growth, and wing form. Data showed that higher rearing densities increased the production of female F. fusca brachypters. There was no consistent difference in the mean developmental periods between the two wing morphs or among all 5 density treatments. The body length of females tended to decrease with increasing rearing density, but there was no significant difference in body size between the two wing morphs when they were reared under the same density level. 相似文献
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《Journal of Asia》2020,23(2):327-335
The insect wing is developed from the wing imaginal disc which is designed from the embryonic ectoderm. To get insight into gene expression profiles in wing discs of Bombyx mori during metamorphosis, we compared the gene expression in the wing between B. mori and B. mandarina moth through RNA-seq. Out of total valid reads identified from the 5th day of 5th instar larvae of silkworm (L5), 7th day of pupae (P7), 1st day of moth (M1) and 1st day of wild silkworm moth (WM1), 20,092,004, 29,251,647, 24,654,695 and 19,753,089 reads were mapped to the mRNA reference sequences of silkworm, respectively. 9229, 7048, 9268 and 6701 differentially expressed genes (DEGs) were respectively recorded in P7 vs L5, M1 vs P7, M1 vs L5 and WM1 vs M1. Further, the peroxisome, ribosome, endocytosis and oxidative phosphorylation pathways were significantly regulated in the metamorphosis of the silkworm. Our study identified 16 orthologous genes with a positive selection from M1, which might be subjected to artificial selection in the domestication of B. mori and would play vital roles in the flight of B. mandarina. 相似文献
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鱼类标志广泛应用于鱼类遗传育种,引种驯化,种群数量变动,鱼类洄游分布,鱼类资源评估等工作。所以,鱼类标志已成为一种重要的研究手段。我们在进行鲫鱼的选育中,深感标志的重要。过去,我们一直采用断伤截鳍(腹鳍或胸鳍)法,效果虽十分明显,但尚未消除截鳍是否影响鱼类生长的疑虑。为此,我们继1985年部分鲫鱼进行软鳍条标志法取得了初步效果后,又于1986年3—10月进行了标志工作,取得了比较满意的结果。 相似文献
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Total testosterone and dihydrotestosterone in blood serum as well as free testosterone in saliva were determined by radioimmunoassay in 110 healthy young men. The results were compared with the development of terminal hair on the trunk and limbs, with the disposition to balding and with the disposition to acne. No significant correlations were found between terminal hair development and absolute androgen levels; however, some significant values were observed in the case of the metabolic rate of dihydrotestosterone/testosterone and the proportion of free to total testosterone. The disposition to balding also correlates positively with the latter ratio. Yet the absolute serum androgen concentrations in men with a disposition to balding is lower than in men with no reduction of scalp hair. The widespread assumption that androgen levels are in general elevated in bald-trait men must therefore be rejected. In accordance with this finding, men with a disposition to balding are morphologically (with regard to anthropometric measures) no more masculine than those with good scalp hair growth. When body build and age are taken into consideration, the relations between terminal hair and androgen ratio are also problematical. No relationship could be found between acne and androgens. 相似文献