塔吉克斯坦苦盏市周边地区夏季鸟类群落多样性     

李叶  周鹿  T.A.卡迪诺夫  时磊 《新疆农业大学学报》2013,(6):472-477

2012-2013年6月至？月份在塔吉克斯坦北部苦盏市周边地区采用点计数法对包括森林草原、荒漠草原、戈壁荒漠、果园、农田等5类有代表性的生境开展鸟类群落多样性调查;同时将涉及的鸟类按食性和捕食区域划分捕食集团研究了不同群落捕食集团的组成特点,结果表明不同生境的鸟类可划分为5类群落,其中农田鸟类种类较丰富香农威纳指数和均匀性指数在5种生境中均最高;森林草原中鸟类种类最少香农威纳指数和均匀度也最低;各种生境条件下群落中杂食性鸟种数比例均为最高,调查结果表明塔吉克斯坦传统的种植制度有利于维持农业生态系统鸟类物种多样性此外捕食集团在温带干旱区也有成为生态环境指标的潜力。  相似文献   

Comparative Genomics for Gene Isolation in Legumes     

The similarity in gene order between closely related taxa suggests that genomic information from model systems should facilitate gene isolation  characterization in target crops.  …… 《分子植物育种》2007,5(2):152-153

The similarity in gene order between closely related taxa suggests that genomic information from model systems should facilitate gene isolation and characterization in target crops. If this is the case, a great deal of effort and investment can be saved by focusing attention on a few model systems that have appropriate applicability. Pea （Pisura sativum） provides a good test case： its genome is large and the insertion sites for repetitive elements, which comprise the bulk of its genome, are highly polymorphic （Jing et al., 2005; Vershinin et al., 2003）, so we expect a great deal of structural polymorphism between the genomes of Pisum lines. Yet the genetic map of Pisum is essentially coUinear with Medicago （Choi et al., 2004; Kalo et al., 2004）.  相似文献   

Improving Drought Tolerance of Rice by Designed QTL Pyramiding   总被引：4，自引：0，他引：4  

Drought is the most important factor limiting rice yields in the rainfed areas of Asia. To overcome the problem  we developed a new strategy ''''designed QTL pyramiding'''' to more efficiently develop drought tolerant 《分子植物育种》2007,5(2):205-206

Drought is the most important factor limiting rice yields in the rainfed areas of Asia. To overcome the problem, we developed a new strategy ＇designed QTL pyramiding＇ to more efficiently develop drought tolerant （DT） rice cultivars. In the first phase of this strategy, we developed large numbers of introgression lines （ILs） in elite backgrounds using backcross （BC） breeding, each of which carries multiple genomic segments for improved DT from a known donor. Then, we genotyped all ILs with SSR markers to track the genomewide pattern of introgression in the DT ILs of 16 BC populations derived from crosses between 2 recipients （IR64 and Teqing） and four different donors. X^2 tests and linkage disequilibrium analyses of introgression in the DT ILs revealed significant frequency shifts at many loci across the genome and non-random associations at the multilocus level as a result of selection for DT in the ILs, which led us to the discovery of putative genetic networks underlying DT in the ILs. The networks each containing all DT loci detected in ILs from a BC population showed some interesting features.  相似文献   

Microsatellite Marker Based Assessment of Genetic Diversity among Cultivars, Landraces and Wild Relatives in Rice     

India being the primary center of origin for rice had a very large treasure of local land races  most of which are out of cultivation today. The exact genetic potential  their differences from commercial varieties  the magnitude of heterogeneity still present in them are not well catalogued. Hence the need to characterize the available land races has become imminent in the modem day concept of crop improvement 《分子植物育种》2007,5(2):257-258

India being the primary center of origin for rice had a very large treasure of local land races, most of which are out of cultivation today. The exact genetic potential and their differences from commercial varieties and the magnitude of heterogeneity still present in them are not well catalogued. Hence the need to characterize the available land races has become imminent in the modem day concept of crop improvement （Rezai and Frey, 1990）. The present study addresses the utility of SSR markers in divulging the genetic relationships at molecular level among the major component factions office gennplasm viz., local cultivars, land races and wild species collected from a wide range of agro-geographical regions of Indian subcontinent.  相似文献   

Aurasperone A Inhibits SARS CoV-2 In Vitro: An Integrated In Vitro and In Silico Study     

Mai H. ElNaggar  Ghada M. Abdelwahab  Omnia Kutkat  Mohamed GabAllah  Mohamed A. Ali  Mohamed E. A. El-Metwally  Ahmed M. Sayed  Usama Ramadan Abdelmohsen  Ashraf T. Khalil 《Marine drugs》2022,20(3)

Several natural products recovered from a marine-derived Aspergillus niger were tested for their inhibitory activity against SARS CoV-2 in vitro. Aurasperone A (3) was found to inhibit SARS CoV-2 efficiently (IC₅₀ = 12.25 µM) with comparable activity with the positive control remdesivir (IC₅₀ = 10.11 µM). Aurasperone A exerted minimal cytotoxicity on Vero E6 cells (CC₅₀ = 32.36 mM, SI = 2641.5) and it was found to be much safer than remdesivir (CC₅₀ = 415.22 µM, SI = 41.07). To putatively highlight its molecular target, aurasperone A was subjected to molecular docking against several key-viral protein targets followed by a series of molecular dynamics-based in silico experiments that suggested M^pro to be its primary viral protein target. More potent anti-SARS CoV-2 M^pro inhibitors can be developed according to our findings presented in the present investigation.  相似文献   

Morphological Characteristics of the Canine and Feline Stomach Mucosa     

P. Zahariev  E. Sapundzhiev  D. Pupaki  P. Rashev  A. Palov  T. Todorov 《Anatomia, histologia, embryologia》2010,39(6):563-568

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Neural network prediction of performance parameters of an inclined plate seed metering device and its reverse mapping for the determination of optimum design and operational parameters   总被引：2，自引：0，他引：2  

M. Anantachar  T. Guruswamy 《Computers and Electronics in Agriculture》2010,72(2):87-98

Seed planting equipment with inclined plate seed metering devices is the most commonly used equipment for planting of peanut crop in India. For obtaining the high yield, it is very essential to drop the peanut seeds in rows maintaining accurate seed rate and seed spacing with minimum damage to seeds during metering. This mainly depends on forward speed of the planting equipment, rotary speed of the metering plate and area of cells on the plate. The relationship between these factors and the performance parameters viz., seed rate, seed spacing and percent seed damage can be established using regression analysis. But they may not be very accurate and may pose difficulty in the determination of inputs for a set of desired outputs (reverse mapping). Hence, an attempt has been made in this paper to develop the feed forward artificial neural network (ANN) models for the prediction of the performance parameters of an inclined plate seed metering device. The data were generated in the laboratory by conducting experiments on a sticky belt test stand provided with a seed metering device and an opto-electronic seed counter. The generated data was used to develop both statistical and neural network models. The performance of the developed models was compared among themselves for 4 randomly generated test cases. The results show that the ANN model predicted the performance parameters of the seed metering device better than the statistical models. In order to determine the optimum forward speed of the planting equipment, peripheral speed of the metering plate and the area of cells on the plate to obtain the recommended seed rate of 33.33 seeds/m², seed spacing of 100 mm and percent seed damage of 0.2% with 100% fill of the cells, a novel technique of reverse mapping using ANN model was followed. It was observed that the optimum forward speed of the planting equipment and optimum area of cells on the metering plate had good correlation with size of seed. Linear regression equations were developed to predict the optimum forward speed of the planting equipment and optimum area of cells on the metering plate using the size of seeds as independent parameter. The peripheral speed of the metering plate of 0.237 m/s was found to be optimum for the size of seeds in the range of 95.42-123.01 mm². However, the results need to be verified by conducting planting operation under actual field conditions.  相似文献   

Movement patterns of Brook Trout in a restored coastal stream system in southern Massachusetts          下载免费PDF全文

Erin L. Snook  Benjamin H. Letcher  Todd L. Dubreuil  Joseph Zydlewski  Matthew J. O'Donnell  Andrew R. Whiteley  Stephen T. Hurley  Andy J. Danylchuk 《Ecology of Freshwater Fish》2016,25(3):360-375

Coastal Brook Trout (Salvelinus fontinalis) populations are found from northern Canada to New England. The extent of anadromy generally decreases with latitude, but the ecology and movements of more southern populations are poorly understood. We conducted a 33‐month acoustic telemetry study of Brook Trout in Red Brook, MA, and adjacent Buttermilk Bay (marine system) using 16 fixed acoustic receivers and surgically implanting acoustic transmitters in 84 individuals. Tagged Brook Trout used the stream, estuary (50% of individuals) and bay (10% of individuals). Movements into full sea water were brief when occurring. GAMM models revealed that transitions between habitat areas occurred most often in spring and fall. Environmental data suggest that use of the saline environment is limited by summer temperatures in the bay. Movements may also be related to moon phase. Compared to more northern coastal populations of Brook Trout, the Red Brook population appears to be less anadromous overall, yet the estuarine segment of the system may have considerable ecological importance as a food resource.  相似文献   

Recruitment of sympatric vendace (Coregonus albula) and whitefish (C. lavaretus) is affected by different environmental factors          下载免费PDF全文

Arne N. Linløkken  Odd T. Sandlund 《Ecology of Freshwater Fish》2016,25(4):652-663

Vendace and whitefish in Lake Osensjøen (boreal south‐east Norway) were studied by means of gillnet test fishing (1976–2013) and hydro acoustic acquisition (1986–2011). Vendace increased in number between 1998 and 2009 while growth and size at maturity decreased. The relative density of whitefish decreased in the pelagic habitat, whereas growth and size remained the same. Both species exhibited varying year‐class strength. Whereas strong year‐classes of both species became less frequent after 1980 than before this, this seemed to change after 2000, especially for vendace. Generalised additive models suggested a strong positive relationship between July/August mean air temperature and year‐class strength of both vendace and whitefish. Whitefish recruitment was also negatively affected by the new regulation regime implemented since 1981, and positively correlated with water level after hatching and by late ice off. The reason for the diverging impacts of environmental factors on the two species may be that vendace spawn in deeper waters that whitefish do. The results indicate that increasing summer temperatures benefit recruitment of both species, whereas low water level and early ice off will harm whitefish recruitment. Both trends are caused by climate warming. It may be speculated that increased density of the specialised plankton feeding vendace may affect the algal community through increased predation on herbivorous zooplankton and potentially affect the trophic state of the lake.  相似文献   

Regression analysis of plasticity and phenotypic stability of hybrid spring soft wheat populations with respect to gluten quality     

V. M. Bebyakin  T. A. Rozanova  L. N. Zlobina 《Russian Agricultural Sciences》2013,39(5-6):396-398

The plasticity and stability of hybrids selected from three heavy-eared populations according to the gluten deformation index GDI-1 are shown. The possibility of testing closely related genotypes by criteria based on ecological regression is examined. Hybrid forms valuable in adaptability that can be used in breeding are found.  相似文献