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排序方式: 共有175条查询结果,搜索用时 15 毫秒
1.
Genetic diversity analysis of two buffalo populations of northern India using microsatellite markers 总被引:3,自引:0,他引:3
R. Arora B. D. Lakhchaura R. B. Prasad M. S. Tantia R. K. Vijh 《Zeitschrift für Tierzüchtung und Züchtungsbiologie》2004,121(2):111-118
The genetic diversity in two buffalo populations of northern India, the Bhadawari and the Tarai was assessed using a set of 22 heterologous (bovine) microsatellite markers. The average number of alleles across all loci in both populations was found to be 4.7, indicating that this set of 22 bovine microsatellite markers could be used to study genetic variation in buffalo species also. The overall polymorphic information content (PIC) value for these markers was 0.54. The average observed and expected heterozygosities for both populations were 0.59 and 0.64, respectively. Common alleles with varying allele frequencies in both populations also represented the genetic variability existing between Bhadawari and Tarai buffaloes. However the θ estimates for population differentiation indicated low levels of differentiation between the two populations. This was further supported by the low genetic distance (0.155) between Bhadawari and Tarai, which was calculated using Nei's standard genetic distance method. The present study on Bhadawari and Tarai populations represents a much‐needed preliminary effort that could be extended to other local buffalo populations of India as well. 相似文献
2.
J. Robison N. Arora Y. Yamasaki M. Saito J. Boone B. Blacklock S. Randall 《Journal of Agronomy and Crop Science》2017,203(6):553-561
Soybean has been considered a cold intolerant species; based largely upon seed germination and soil emergent evaluations. This study reports a distinct acquisition of cold tolerance, in seedlings, following short acclimation periods. Diversity in cold responses was assessed in eight cultivars of Glycine max and six accessions of G. soja. All varieties of soybean significantly increased in freezing tolerance following acclimation. This study indicates soybean seedlings are indeed capable of sensing cold and acquiring cold tolerance. Germination rates after cold imbibition were negatively correlated with maturity group, but positively correlated with cold acclimation potential in G. soja. Seed fatty acid composition was varied between the species, with Glycine soja accessions containing about 2‐times more linolenic acid (18:3) than G. max. Furthermore, high levels of linoleic acid (18:2) in seeds were positively correlated with germination rates following cold imbibition in G. soja only. We suggest that domestication has not impacted the overall ability of soybean to cold acclimate at the seedling stage and that there is little variation within the domesticated species for ability to cold acclimate. Thus, this brief comparative study reduces the enthusiasm for the “wild” species as an additional source of genetic diversity for cold tolerance. 相似文献
3.
Maria Garcia-Martin Nora Fagerholm Claudia Bieling Dimitris Gounaridis Thanasis Kizos Anu Printsmann Matthias Müller Juraj Lieskovský Tobias Plieninger 《Landscape Ecology》2017,32(11):2133-2150
Context
Human–nature interactions are reflected in the values people assign to landscapes. These values shape our understanding and actions as landscape co-creators, and need to be taken into account to achieve an integrated management of the landscape that involves civil society.Objectives
The aim of this research was to increase the current knowledge on the most and least common landscape values perceived by local stakeholders, the patterns in the spatial distribution of values, and their connection to different socio-economic backgrounds and landscape characteristics across Europe.Methods
The research consisted of a cross-site comparison study on how landscape values are perceived in six areas of Europe using Public Participation GIS surveys. Answers were analysed combining contingency tables, spatial autocorrelation and bivariate correlation methods, kernel densities, land cover ratios, and viewshed analyses. Results were discussed in the light of findings derived from other European participatory mapping studies.Results
We identified shared patterns in the perception of landscape values across Europe. Recreation, aesthetics, and social fulfilment were the most common values. Landscape values showed common spatial patterns mainly related to accessibility and the presence of water, settlements, and cultural heritage. However, respondents in each study site had their own preferences connected to the intrinsic characteristics of the local landscape and culture.Conclusions
The results encourage land planners and researchers to approach landscape values in relation to socio-cultural and bio-physical land characteristics comprehensibly, acknowledging the complexity in the relationship between people’s perception and the landscape, to foster more effective and inclusive landscape management strategies.4.
In this paper, we investigate how the innovation expectations of public financiers are related to realized patents. The analysis is based on a novel data set of collaborative R&D projects subsidized by the Finnish Agency of Technology and Innovation (Tekes) and the European Regional Development Fund (ERDF) during the period 2000–2004. Innovation expectations are measured using reports submitted by Tekes experts during ex ante assessments of projects. Our probit model results reveal that Tekes' patent expectations are positively related to realized patents for projects led by private firms (but not by public organizations). For large organizations, Tekes' innovation expectations are better at predicting patenting. 相似文献
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Detached wheat ears (15 days post-anthesis) were cultured in liquid nutrient medium containing different sucrose concentrations (2. 6 and 10%). The volume of solution taken up was highest from 2% sucrose solution and decreased with increasing sucrose concentration. Grain development in terms of grain weight, glumes and rachis weight, nitrogen and protein content showed a linear increase in these variables over 11 days. Dry weight per grain increased with the sucrose level in the medium and the reduced uptake of solution did not decrease the moisture percentage of the grain. The culture of ears decreased the solution pH more with 2% than with 10% sucrose. Addition of 0.5% chloramphenicol to the culture solution had no adverse effect on grain weight, rather it prevented contamination and maintained a higher pH of the solution. 相似文献
8.
Correlations between leaf abscisic acid concentration ([ABA]), stomatal conductance (gs), rate of stomatal opening in response to an increase in leaf water potential (si), shoot hydraulic conductance (L) and photosynthetic characteristics were examined in saplings of six temperate deciduous tree species: Acer platanoides L., Padus avium Mill., Populus tremula L., Quercus robur L., Salix caprea L. and Tilia cordata Mill. Species-specific values of foliar [ABA] were negatively related to the mean values of gs, si, L and light- and CO2- saturated net photosynthesis (P(max)), thus providing strong correlative evidence of a scaling of foliar gas exchange and hydraulic characteristics with leaf endogenous [ABA]. In addition, we suggest that mean gs, si, L and Pmax for mature leaves may partly be determined by the species-specific [ABA] during leaf growth. The most drought-intolerant species had the lowest [ABA] and the highest gs, suggesting that interspecific differences in [ABA] may be linked to differences in species-specific water-use efficiency. Application of high concentrations of exogenous ABA led to large decreases in gs, si and P(max), further underscoring the direct role of ABA in regulating stomatal opening and photosynthetic rate. Exogenous ABA also decreased L, but the decreases were considerably smaller than the decreases in gs, si and Pmax. Thus, exogenous ABA predominantly affected the stomata directly, but modification of L by ABA may also be an important mechanism of ABA action. We conclude that interspecific variability in endogenous [ABA] during foliage growth and in mature leaves provides an important factor explaining observed differences in L, gs, si and Pmax among temperate deciduous tree species. 相似文献
9.
Anu Rastogi Brij Kishore Mishra Munna Singh Ritu Mishra 《Archives of Agronomy and Soil Science》2013,59(10):1389-1409
The adequate growth of plants can be achieved only by a balanced ratio of biologically active nutrients in soil along with its readily availability. Linseed seems to be an advantageous secondary oilseed crop widely used in industrial purposes, which can serve additional purpose of phytoextraction of heavily infested soils with heavy metals. In this study, we have made an effort to find out the optimum dose of heavy metals necessary as micronutrients like copper (Cu), iron (Fe) and zinc (Zn) for the enhancement of linseed yield along with the distribution of heavy metals in different plant parts. Quantitative enhancement in different traits of linseed plant due to Cu, Fe and Zn fertilization especially for capsules per plant after maturity suggested positive association between heavy metal supply and morphological traits, which indirectly enhanced seed yield. There was a positive correlation between Zn supply and seed yield. In the treatments with Cu and Fe fertilization, seed yield was positively correlated to plant height, capsules per plant and seeds per five capsules. According to this study, it is concluded that linseed has the ability to accumulate majorly Fe followed by Cu and Zn. 相似文献
10.
Maria Holmberg Anu Akujärvi Saku Anttila Lauri Arvola Irina Bergström Kristin Böttcher Xiaoming Feng Martin Forsius Inese Huttunen Markus Huttunen Yki Laine Heikki Lehtonen Jari Liski Laura Mononen Katri Rankinen Anna Repo Vanamo Piirainen Pekka Vanhala Petteri Vihervaara 《Landscape Ecology》2015,30(3):561-577