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1.
Individuals attach great importance to different attributes for mountaineering jackets, and the relative importance of high-performance fabric differs according to individuals. Needs-based segmentation attempts to understand these differences by grouping together people who assign a similar level of importance to the same attributes. We focused on identifying market segments for high performance mountaineering jackets, comparing with the relative attribute preference for mountaineering jackets of high-performance fabrics according to segmented clusters, and testing to establish if there were significant differences between clusters. Conjoint analysis was conducted by sampling 120 mountaineering club members, who ranked preferences for a hypothetical mountaineering jacket with high-performance fabrics based on profiles derived from an orthogonal array. Five attributes were used in the conjoint analysis: weight, durability, breathability, water/windproof, and price. Two consumer segments emerged, and there were two clusters with different ideal jacket profiles: a price sensitive group and a functional property-seeking group. The price sensitive group ranked the price of jacket attribute as the main factor determining their preference, followed by water/windproof, breathability, durability, and weight. The functional propertyseeking group considered breathability as the most important attribute, followed by water/windproof, durability, price, and weight. Differences in the preferences for the price and breathability attributes were the highest between both clusters. The results from this research provided insight into strategies that may be used successfully by developers of fabrics for mountaineering jackets.  相似文献   

2.
The purpose of this paper is to analyse the impact of design solutions on the thermal insulation of the garments and the ensembles. Previous studies investigated the microclimatic air gaps and volumes, however only under the first - and the second - layered clothing. Since none of the previous studies covered three - layered ensembles, in this study ensembles were accompanied by jackets of different fit and length to investigate the ensembles’ thermal insulation. Variants of bomber jacket differ in the amount of the ease allowance, while variants of the parka differ in length. The thermal insulation of the ensembles increased for 21.6 to 59.7 % when one of the jacket variants was added as the outerwear garment. A threshold volume, after which the thermal insulation will start to decrease due to convection, wasn’t determined for the outerwear third - layered garments nor was the impact of the length of the garment on the thermal insulation clearly stated. This study involved laboratory testing of garments and ensembles by 3D body scanning and thermal manikin measurements. To evaluate the volume of the microclimatic air volume the accurate 3D body scanning was used and the impact of the microclimatic volume on the ensemble’s insulation was tested. The thermal insulation for the selected outerwear garments and afterwards ensembles was measured by resting thermal manikin. Analysis of the results obtained from tests, showed that the garments’ fit and length can be used to model the overall thermal insulation of the ensembles. The ensembles insulation enlargement was measured for microclimatic volumes up to 33.57 dm3 (measured with ensembles accompanied with bomber jacket). The study proved that the limiting microclimatic volume is greater for three - layered clothing, than previously reported. The overall ensembles’ insulation increased simultaneously with the length enlargement (measured with ensembles accompanied with parka jacket). Findings will be of help in the future research on garments and ensembles thermal properties modelled through the design process and the construction.  相似文献   

3.
Application of slurry in spring to grassland in north‐west Europe increases the efficiency of nitrogen recovery compared with the application in summer. In Ireland, however, more than 0·50 of slurry is applied in the summer. The splash‐plate method of application, most commonly used in Ireland, can make application in spring difficult because of the risk of contamination of grass with slurry, affecting subsequent silage quality and grazing preferences. This study evaluated the potential of low‐emission spreading methods to increase the opportunity for spring application of slurry using an agro‐meteorological modelling approach. Weather data from two weather stations were combined with data on grass growth from two nearby sites. Using three soil‐drainage classes (well, moderate and poor), each with a typical regime of grassland management, a database of soil moisture deficits, drainage, patterns of grazing and cover of grass herbage was developed for three hypothetical management systems, one for each soil drainage class, at each site. Simulations of four slurry application methods [splash‐plate (SP), band‐spreader (BS), trailing‐shoe (TS) and shallow‐injection (SI)], subject to a series of constraints, were compared over an 8‐year period (1998–2005) in order to determine the number of days during the period from 1 January to approximately 10 May of each year, when it was considered that grassland was suitable for application of slurry. These constraints were: (i) restrictions on spreading imposed by current legislation in Ireland; (ii) the period before occurrence of drainage or overland flow; (iii) soil trafficability; (iv) the time‐lag before a subsequent grazing or harvest event; and (v) herbage mass of the pasture. On well and moderately drained soils, the model predicted that the highest number of days available for slurry spreading was found for the TS method followed by the BS, SI and SP methods. There was no difference between application methods in the number of available days on poorly drained soils.  相似文献   

4.
利用分子标记对控制玉米脂肪合成的关键基因进行定位,从分子水平上阐明其遗传机理,提高高油玉米的育种效率。以吉林省80份核心玉米自交系为关联群体,2014年和2015年分别在吉林农业大学试验地进行田间试验,将自交收获的果穗晾晒脱粒后用NIRFlex N-500近红外光谱仪测定其子粒脂肪含量。同时使用Illumina PE150测序仪对80份玉米自交系进行全基因组重测序,共获得1 490 007个高质量的SNP用于后续的关联分析。结果表明,玉米子粒脂肪含量的变异范围为2.83%~6.81%,广义遗传力为63.3%。经过两年1点的全基因组关联分析共筛选得到10个SNP位点与子粒的脂肪含量显著关联(P0.000 001),解释的表型贡献率为0.65%~34.5%,其中位于染色体框4.01的SNP标记表型贡献率最高为34.5%。在显著性SNP位点(P0.000 001)的连锁不平衡区域(5.2 kb)内共挖掘出6个候选基因,分别预测编码MYB转录因子、果胶酯酶、谷氨酰胺合成酶和3种无特征功能的假定蛋白,可能与脂肪的合成代谢密切相关,可为高油玉米材料的分子标记辅助选择及克隆调控玉米子粒脂肪含量的关键基因提供参考。  相似文献   

5.
Bread wheat (Triticum aestivum L.) quality is a key trait for baking industry exigencies and broad consumer preferences. The main goal of this study was to undertake quantitative trait loci (QTL) analyses for bread wheat quality in a set of 79 recombinant inbred lines (RILs) derived from a soft × hard bread wheat cross. Field trials were conducted over two years, utilizing a randomized complete block design. Dough quality was evaluated by sedimentation test, mixograph and alveograph analysis. Protein content was measured by near-infrared reflectance analysis and grain hardness was determined by the single kernel characterization system (SKCS).  相似文献   

6.
Prediction of impact by near-infrared reflectance spectroscopy (NIRS) analysis of rodent diet preferences was evaluated in four dominant field rodents in Moravia farmland (Czech Republic). These include the common vole (Microtus arvalis), pygmy field mouse (Apodemus uralensis), wood mouse (Apodemus sylvaticus), and black-striped field mouse (Apodemus agrarius). Using fecal samples, this method predicts the proportions of food components consumed, based on a calibration equation developed through feeding tests in the laboratory. We used the wood mouse as a model species for NIRS device calibration. The two types of monofood feces collected from mice that were fed with either barley or wheat grain were mixed to form a series of increasing proportions of wheat feces subsequently measured by NIRS. Because of a good fit, the calibration equation was then applied to other mice, whereas a separate calibration equation had to be developed for the common vole. The percentage diet preferences were determined by comparing feces from preference choice tests with the calibration equation. Whereas all mice preferred wheat to barley, the common vole showed no preference for either crop. Thus proportion of wheat preference by all Apodemus sp. predict stronger impact of these in wheat fields in ripe stage than in barley one.  相似文献   

7.
An extruded plastic windbreak netting, with an optical porosity of 64%, was used to evaluate its potential in reducing sprayer air velocity and intercepting spray droplets in simulated orchard applications. The air velocity reduction was assessed in laboratory tests carried out under static and dynamic conditions. In field tests, the netting was directly sprayed with two orchard airblast sprayers, equipped with different nozzle types.Air velocity reduction was higher in the dynamic setting but decreased at lower air velocities. It also decreased when the netting distance from the air outlet increased. In field tests, the analysis of spray fallout depositions in open area conditions revealed lower recovery rate for conventional than air induction hollow cone nozzles. Comparing the fallout collected on sampling lines (perpendicular to the sprayer travel path) behind the netting and in the open area showed an average spray retention of 30.5% for the netting. The netting affected the fallout pattern along the sampling line, showing a droplet trajectory deflection associated with the momentum and kinetic energy losses. An increase of ground deposition was noticed just behind the netting (up to 2 m). At farther distances ground deposits decreased considerably. The results showed the potential for using a windbreak netting to simulate the droplet retention characteristics of a hypothetical tree foliage, in order to reduce the effect of canopy variability in certain orchard applications studies.  相似文献   

8.
Crop genebank managers must be concerned with preserving low-frequency alleles that are vulnerable to being lost from the genebank because they are not sampled as seed increase parents. Traits conferred by such alleles are also vulnerable to being overlooked because they are not sampled in plants evaluated for breeding traits. Mathematical models and recommendations that follow from hypothetical vulnerable alleles within single populations have been made by various researchers. This work was undertaken to empirically detect the prevalence of such alleles in the US Potato Genebank by extrapolation from RAPD markers. Two outcrossing species known to be very heterogeneous were selected,Solanum jamesii Torr. (2n=2x=24) andSolanum sucrense Hawkes (2n=4x=48). RAPD band frequencies at a total of 83 marker loci within each of 15 populations were assessed using 24 plants per population. For both species, about 10% of within-population loci had vulnerable alleles (banded plant frequency < 40%), considering just the particular population in question. However, about half of these were fixed in at least one other population (making that marker invulnerable to loss). The highest within-population banded plant frequency for loci not fixed in any population was, with one exception, always > 40%. So, while several alleles may be vulnerable within a given population, these were nearly always fixed or nearly fixed (invulnerable) in another population. This suggests that the safest strategy for maximizing conservation of alleles is to apportion available resources over many separate populations, rather than adopt a preservation protocol so rigorous that it can only be practically applied to a limited number of populations.  相似文献   

9.
When explicit measures are taken to account for the needs of clients (farmers and consumers) it results in highly client-oriented breeding. This involves the participation of farmers to specify the design of desirable varieties and, once they are produced, their testing without delay with the target clients in the target environments. The term highly client-oriented breeding (COB) explains the purpose of farmer involvement – the deliberate achievement of a high degree of client orientation – rather than simply explaining the process of farmers participating in plant breeding (participatory plant breeding). Client-oriented breeding is sometimes based on the preferences of relatively few farmers in a small area, so a possible drawback is that it will produce varieties that are too locally adapted. We describe the testing of varieties in the High Barind Tract (HBT) of Bangladesh from a COB programme carried out in Chitwan district, Nepal. The two best lines, Judi 582 and Judi 567, yielded 19–50% more during the T. Aman season and 106% more during the Aus season than check varieties in the HBT. Research to determine farmers’ preferences and adoption consistently showed these varieties were preferred over all available alternatives. The new varieties were broadly adapted as they were superior in all the three rice-growing seasons over varying levels of inputs. This broad adaptation could be explained by the breeding method: the generations were advanced in two contrasting seasons and each generation was grown on a different farmer's field under different management and planting dates. Because the segregating generations were grown under moderate and fluctuating levels of nitrogen, it is to be expected that genotypes with good nitrogen use efficiency will be selected that can also respond to added nitrogen. Overall, the cost-effectiveness of COB was high as it produced widely adapted genotypes from a small breeding programme, and knowledge of farmers’ preferences increased the efficiency of targeting new germplasm.  相似文献   

10.
A survey of 80 table-stock yields in New Brunswick revealed an incidence of 3.8% of potato spindle tuber virus among the three major varieties Kennebec (3.3%), Katahdin (2.5%), and Netted Gem (Russet Burbank (4.6%)). Concurrentily, in a field trial, three isolates of the mild strain of the virus (MPSTV) reduced yield in the variety Saco by 17%, 24%, and 24%, respectively, and the severe strain (SPSTV) reduced yield by 64%. An earlier preliminary survey had shown that in Eastern Canada, MPSTV prevailed over SPSTV on a ratio of 11∶1, thus a hypothetical loss of 1% could be calculated, conservative compared with Le Clerg et al. (1944) (2.6% loss by 4% incidence of PSTV), perhaps because of a lower incidence of SPSTV.  相似文献   

11.
The introduction of a new cultivar in a process-based crop simulation model requires the estimation of cultivar coefficients that define its growth and development characteristics. An accurate estimation of these coefficients requires replicated field experiments that, in many cases, are not available to crop model users. The objective of this study was to employ a pattern recognition approach to estimate cultivar coefficients from a minimum set of experimental data for use with a crop simulation model. The pattern recognition approach is based on similarity measures. Its main goal is to classify groups of data or patterns based on either a priori knowledge or on statistical information extracted from the patterns. Based on the similarity measure as the central calculation of the pattern recognition approach, the algorithm searches the space of features of other cultivars in the database to find the most similar cultivar as the best match to the target cultivar. The approach of this study was based on a few key characteristics of maize crop growth and development, including anthesis and harvest maturity dates, maximum leaf area index (LAImax), final above ground biomass, and grain yield, which were used as the features vector. To construct the feature database, 27,789 hypothetical cultivars were constructed by combining different values of the six cultivar coefficients of the Cropping System Model (CSM)-CERES-Maize. Experiments performed in Florida (FL) and Iowa (IA) USA, Spain, central Punjab, Pakistan, and in Piracicaba, SP, Brazil were selected and later modified to provide a full potential production environment. The crop model was run for potential production for all 27,789 hypothetical cultivars and the outputs of these simulations were used as the feature database. For evaluation of this approach, we used the features for 29 different maize cultivars as reported from field experiments that are available in DSSAT maize cultivar database and also for four additional cultivars of which two had not been used in any aspect of this study. The model was run for all 33 cultivars, using the best match cultivar coefficients, for the conditions of the three study sites and locations where the latter four cultivars have been grown. The simulated crop characteristics were compared with the same simulated crop characteristics based on the original coefficients used to run the simulation model. We found that the approach based on pattern recognition was able to estimate the cultivar coefficients with a reasonable accuracy. The coefficient of determination (r2), root mean square difference (RMSD), and relative root mean square of difference (RMSDr) confirmed that this approach provided reliable estimates for the maize cultivar coefficients. The highest R2 (0.98) was obtained for anthesis in Florida and the lowest (0.57) was obtained for grain yield in Spain. The highest RMSD (8.8) was obtained for maturity in Spain, while the lowest RMSD (1.1) was obtained for aboveground biomass in Florida. Although the values for RMSD were different across the different sites, this approach provided a level of accuracy that might be acceptable, especially for users who only have one year of experimental data and demand the best possible initial guess for the coefficients of their specific cultivar. This approach has been implemented in a simple tool that can be easily applied by users of DSSAT and the CSM-CERES-Maize model.  相似文献   

12.
Essential oils were extracted by hydrodistillation from the leaves of Cryptomeria fortunei from the principal habitats in China. The essential oil yields of samples from various locations ranged from 0.61 to 1.66% (w/w). GC-MS analysis revealed eighty-seven compounds, constituting 85.89-94.75% of the total essential oils. The main constituents were kaurene (0-44.69%), phyllocladene (0.07-32.98%), kaur-16-ene (0-32.28%), elemol (5.28-18.92%), α-cadinol (0-11.39%), α-eudesmol (0-11.21%), α-pinene (2.32-9.15%). The samples were separated into 3 chemotypes by hierarchical cluster analysis, according to the composition of the corresponding essential oils. Chemical composition of essential oils was significantly related to nine geographic distributions among populations. Our results revealed chemical polymorphism in the essential oils of the C. fortunei leaf in China. The chemical variability could be attributed to genetic and environmental factors. The chemical diversity of the oils offers opportunity to choose C. fortunei leaves and essential oils with preferential compound for green plant protection, pharmaceutical, perfume and food industries.  相似文献   

13.
Sweet potato weevils (Cylas spp.) are among the most important constraints to sweet potato (Ipomoea batatas [L.] Lam.) production in most agro-ecological zones of Tanzania. Integration of farmers’ perception on sweet potato weevil damage, production constraints, and variety preferences is crucial in developing sweet potato varieties with farmer-preferred traits and weevil resistance. The aim of this study was to identify farmers’ perceptions on sweet potato weevil damage, production constraints, postharvest storage options, and criteria used to select and grow the best sweet potato varieties in western Tanzania. Surveys were conducted in four selected districts of western Tanzania (Nzega, Sikonge, Kigoma rural, and Kasulu) known for sweet potato production. Data were collected using a structured questionnaire, focus group discussions (FGDs), and transect walk involving 122 sweet potato farmers. Weevil damage was reported by 84% of the respondents to be the overriding constraint to sweet potato production. Sweet potato diseases and drought were the next production constraints, reported by 57% and 54% of the respondents, respectively. Farmers’ preferred agronomic traits of sweet potato included high yield (25% of respondents), drought tolerance (24%), and disease and pest resistance (21%). Farmers’ preferred sweet potato culinary traits in the study areas were high dry matter content (reported by 21% of the respondents), followed by reduced cooking time, taste and fiber content (each reported by 19% of the respondents). The above-mentioned production constraints and farmers’ preferred traits are useful selection criteria for improving sweet potato with respect to weevil resistance and enhanced storage-root yield and quality.  相似文献   

14.
This paper discusses the hand and preference of stretch fabrics for sportswear through subjective and objective hand evaluations. Twenty-two varieties of stretch fabrics for fall/winter sportswear fabrics were used. Seven main factors were classified through subjective evaluation and total cumulative variance value was 68.28 %. According to correlations between objective hand and preference, there are differences in preferences for pants and shirts, and in response to preference for shirts, no gender differences are observed. Correlations between subjective hand and preference show that there is a similar tendency in preferences for pants and shirts regardless of usage by different genders.  相似文献   

15.
The preference intensities of Japanese Medaka Fish (Japanese killifish, Oryzias latipes) to the three environmental factors of water depth, current velocity, and cover are discussed in this paper. Mathematical models of preference intensities for Japanese Medaka Fish to the three environmental factors were constructed in laboratory open-channel experiments. A simple genetic algorithm for the optimal functional representation of preference intensity was introduced. The models were then verified by on-the-spot examinations. The results indicated that the maximum preference level of Japanese Medaka Fish was a water depth of 9.4 cm and a current velocity of 2.8 cm/s. The all-cover condition was considerably high compared with other cover conditions. The relative weights of the three environmental factors were 0.32 for depth, 1.0 for velocity, and 0.66 for cover, when the maximum weight was normalized. The weight values suggested that the environmental preferences of Japanese Medaka Fish were not greatly affected by water depth. Judging from the agreement between the predicted and observed distributions in considering the two factors of current velocity and cover, these two factors obviously affected the environmental preferences of Japanese Medaka Fish.  相似文献   

16.
The discovery of novel natural products (NPs) that will serve as lead structures has to be an ongoing effort to fill the respective development pipelines. However, identification of NPs, which possess a potential for application in e.g., the pharma or agro sector, must be as cost effective and fast as possible. Furthermore, the amount of sample available for initial testing is usually very limited, not least because of the fact that the impact on the environment, i.e., the sampled biosystem, should be kept minimal. Here, our pipeline SeaPEPR is described, in which a primary bioactivity screening of crude extracts is combined with the analysis of their metabolic fingerprint. This enabled prioritization of samples for subsequent microfractionation and dereplication of the active compounds early in the workflow. As a case study, 76 marine sponge-derived extracts were screened against a microbial screening panel. Thereunder, human pathogenic bacteria (Escherichia coli ATCC35218 and Staphylococcus aureus ATCC33592) and yeast (Candida albicans FH2173), as well as the phytopathogenic fungus Septoria tritici MUCL45407. Overall, nine extracts revealed activity against at least one test organism. Metabolic fingerprinting enabled assigning four active extracts into one metabolic group; therefore, one representative was selected for subsequent microfractionation. Dereplication of the active fractions showed a new dibrominated aplysinopsin and a hypothetical chromazonarol stereoisomer derivative. Furthermore, inhibitory activity against the common plant pest Septoria tritici was discovered for NPs of marine origin.  相似文献   

17.
胡麻种质资源主要品质性状的分析与评价   总被引:2,自引:0,他引:2  
为了充分利用胡麻种质资源,促进胡麻品质育种,对国内外280份胡麻种质资源的主要品质性状进行了测定分析。结果表明:(1) 280份资源的粗脂肪平均含量38.3%,变幅为35.12%~45.27%,变异系数最小(3.22%);木酚素平均含量3.45 mg/g,变幅1.08~7.24 mg/g,变异系数最大(30.88%);亚麻酸含量平均48.03%,变幅35.62%~57.82%,变异系数为7.07%。(2) 相关分析显示,粗脂肪含量与油酸含量极显著负相关,与硬脂酸含量负相关,与其他性状正相关;木酚素含量与亚油酸含量极显著正相关,与棕榈酸含量正相关,与硬脂酸、油酸、亚麻酸含量负相关;亚麻酸含量与棕榈酸、硬脂酸、油酸和亚油酸含量显著负相关。(3) 主成分分析将主要品质性状聚为4个主成分,油酸因子、亚油酸因子,木酚素因子和粗脂肪因子。(4) 系统聚类分析在欧氏距离D=42.8水平上聚为5大类群,第Ⅰ类粗脂肪和亚麻酸含量比较高;第Ⅱ类木酚素和亚油酸含量比较高;第Ⅲ类棕榈酸和硬脂酸含量比较高;第Ⅳ类油酸含量比较高;第Ⅴ类亚油酸含量比较低。以上分析可为胡麻种质资源利用和品质育种提供依据。  相似文献   

18.
Exposure to β-N-methylamino-l-alanine (BMAA) might be linked to the incidence of amyotrophic lateral sclerosis, Alzheimer’s disease and Parkinson’s disease. Analytical chemistry plays a crucial role in determining human BMAA exposure and the associated health risk, but the performance of various analytical methods currently employed is rarely compared. A CYANOCOST initiated workshop was organized aimed at training scientists in BMAA analysis, creating mutual understanding and paving the way towards interlaboratory comparison exercises. During this workshop, we tested different methods (extraction followed by derivatization and liquid chromatography coupled to tandem mass spectrometry (LC-MS/MS) analysis, or directly followed by LC-MS/MS analysis) for trueness and intermediate precision. We adapted three workup methods for the underivatized analysis of animal, brain and cyanobacterial samples. Based on recovery of the internal standard D3BMAA, the underivatized methods were accurate (mean recovery 80%) and precise (mean relative standard deviation 10%), except for the cyanobacterium Leptolyngbya. However, total BMAA concentrations in the positive controls (cycad seeds) showed higher variation (relative standard deviation 21%–32%), implying that D3BMAA was not a good indicator for the release of BMAA from bound forms. Significant losses occurred during workup for the derivatized method, resulting in low recovery (<10%). Most BMAA was found in a trichloroacetic acid soluble, bound form and we recommend including this fraction during analysis.  相似文献   

19.
美国引进甘蔗品种对黑穗病的抗性鉴定与初步评价   总被引:1,自引:0,他引:1  
为筛选出抗甘蔗黑穗病的优异亲本材料,采用人工浸渍接种法对27个甘蔗品种进行1年新植试验的黑穗病抗性鉴定。通过潜育期(LP)、持续发病期(SDD)、累计丛发病率(IP)、累计茎发病率(IS)和病情进展曲线下的面积(AUDPC)这5个病情参数,结合标准对照种的抗性表现,综合评价参试品种的抗性,并采用系统聚类分析进行验证。结果表明:5个病情参数之间的相关性均达到极显著水平,是甘蔗黑穗病抗性鉴定与评价的重要指标。参试品种中,未发病品种6个,占22.22%;高抗(HR)品种5个,占18.52%;抗病(R)品种10个,占37.04%;中抗(MR)品种1个,占3.70%;中感(MS)品种2个,占7.41%;感病(S)品种3个,占11.11%。系统聚类分析的结果与参试甘蔗品种的抗性表现一致。  相似文献   

20.
Interactions between sward diversity and forage selectivity of cattle and sheep managed within mixed grazing systems are not fully understood. The objective of this study was to investigate the effect of either mono‐ or co‐grazing of sheep and cattle on swards differing in botanical composition (either diverse or grass‐dominated) on the intake choices of six target forage species. Jacobs' selection index (JSI) was employed to quantify the preference for single target species in relation to their proportion in the sward. Results revealed distinct intake preferences of sheep and cattle; as expected, sheep were more selective than cattle. To a lesser extent, the sward composition had an effect on intake preferences: cattle responded to botanical composition by changing their intake preferences, but to a lesser extent than sheep. Phleum pratense was the most preferred target forage species (JSI = 0.62). Lolium perenne, Taraxacum sect. Ruderale and Trifolium repens were also highly preferred regardless of sward composition or type of grazing (JSI = 0.47, 0.32 and 0.27 respectively). Dactylis glomerata and Festuca pratensis tended to increase in abundance after grazing events in both diverse and grass‐dominated swards. Co‐grazing of cattle and sheep facilitated a more homogeneous consumption of the target forage species evaluated.  相似文献   

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