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排序方式: 共有521条查询结果,搜索用时 15 毫秒
1.
白粉病是瓜类作物重要病害之一。本研究采用苗期人工接种方法,研究了117份瓠瓜微核心种质对白粉病的抗性,并基于不同材料的病情指数和基因型数据,进行全基因组关联分析(genome-wide association analysis,GWAS)。利用2014年和2018年的抗病表型数据,分别鉴定到22个和13个与白粉病抗性相关的SNPs,其中2个SNPs位点在两年试验中同时被检测到。进一步研究发现不同瓠瓜材料的白粉病抗性与其携带有利等位变异数目成正相关。本研究为克隆瓠瓜抗白粉病相关基因、研究其抗病机制提供科学依据,促进了瓠瓜抗白粉病分子育种。 相似文献
2.
There is limited research to study how moist heating affects internal structure of barley grain on a molecular basis. The objectives of this study were to use vibrational molecular spectroscopy: 1) to determine the moist heating induced changes of barley carbohydrate (CHO) structure on a molecular basis, 2) to study the effects of moist heating on CHO chemical profiles, Cornell Net Carbohydrate and Protein System (CNCPS) subfractions, in situ rumen degradation, and predicted intestinal carbohydrate supply of barley grain; and 3) to reveal the association between molecular structure spectral features and CHO related metabolic characteristics. Barley samples (CDC cowboy) were collected from Kernen Crop Research Farm (Saskatoon, Canada) during two consecutive years. Half of each sample was kept as raw barley and the other half underwent moist heating (autoclaving at 120 °C for 60 min). The molecular spectroscopy (attenuated total reflectance-fourier transform infrared, ATR-FTIR) was used to detect the barley CHO related molecular structure spectral features. Moist heating did not affect carbohydrate related chemical profiles and CNCPS subfractions but it decreased rumen degradable carbohydrate. Rumen undegradable and intestinal digestion of CHO subfractions were not affected by moist heating. The advanced vibrational molecular spectroscopy can be used to detect carbohydrate molecular spectral features. Nutrient utilization prediction using molecular spectral characteristics is warranted and further investigation is encouraged. 相似文献
3.
Increases in the proportion of amylose in the starch of wheat grains result in higher levels of resistant starch, a fermentable dietary fiber associated with human health benefits. The objective of this study was to assess the effect of combined mutations in five STARCH BRANCHING ENZYME II (SBEII) genes on starch composition, grain yield and bread-making quality in two hexaploid wheat varieties. Significantly higher amylose (∼60%) and resistant starch content (10-fold) was detected in the SBEII mutants than in the wild-type controls. Mutant lines showed a significant decrease in total starch (6%), kernel weight (3%) and total grain yield (6%). Effects of the mutations in bread-making quality included increases in grain hardness, starch damage, water absorption and flour protein content; and reductions in flour extraction, farinograph development and stability times, starch viscosity, and loaf volume. Several traits showed significant interactions between genotypes, varieties, and environments, suggesting that some of the negative impacts of the combined SBEII mutations can be ameliorated by adequate selection of genetic background and growing location. The deployment of wheat varieties with increased resistant starch will likely require economic incentives to compensate growers and millers for the significant reductions detected in grain and flour yields. 相似文献
4.
何耀曾先生(1920—2010)是重庆复旦大学茶叶专修科的第一届毕业生(1944),从那时起,他为中国茶业的兴盛工作了六十多年。在他去世前的三年里,我曾多次访问他,记下了他的回忆和他与张志澄、钱梁、吴觉农先生的往来。 相似文献
5.
农民大学生移动学习探索 总被引:2,自引:1,他引:1
通过调查分析农民大学生的特征以及移动学习的特点和优势,发现移动学习能够对农民大学生的课程学习起到促进作用,提高学习效率,是一种重要的远程教育方式。 相似文献
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本试验以宁夏地区8个公牛家系的各8头女儿共计64头中国荷斯坦母牛为研究对象.利用AB13730测序仪对DGAT2基因Exon4进行了基因型检测后发现三个突变位点474bp(C/G)、48lbp(G/A)、621bp(C/T),各个位点发现有两种基因型,分别为CC型、GC型,GG型、GA型,CC型和CT型,基因型频率分别为0.484、0.516,0.687、0.313,0.484和0.516。通过SAS软件(8.02)对4个产奶性状与DGAT2基因Exon4的关联分析表明.474bp(C/G)CG型305d产奶量和乳脂率显著高于CC型(P〈0.05),乳蛋白率、体细胞数影响不显著(P〉0.05);481bp(G/A)GA型305d产奶量显著高于GG型,与乳脂率、乳蛋白率、体细胞数无显著的相关性(P〉0.05);621bp(C/T)CT型305d产奶量、乳蛋白率、体细胞数都显著高于CC型(P〈0.05),乳脂率影响不显著(P〉O.05)。 相似文献
9.
发展劳务经济 促进小康建设--对提高安徽农村居民收入的思考 总被引:1,自引:0,他引:1
农民收入低是农村小康建设的难点.根据安徽省的资源禀赋和农村剩余劳动力存量巨大的现实,因势利导地发展劳务经济,既对提高农民收入具有现实作用,也必将对加快全面建设小康社会的进程起到积极的推动作用. 相似文献
10.
Rumesh Ranjan Ashish Kumar Swarupa Nanda Mandal 《Acta Agriculturae Scandinavica, Section B - Plant Soil Science》2013,63(7):588-595
ABSTRACT Nitrogen uptake being part of nitrogen use efficiency (NUE) is largely decided by root traits. Root traits variability has hardly been explored by breeders mainly because of difficulties in scoring. The hydroponic system requiring lesser space for precise phenotyping of large numbers of genotypes independently of the growing season can be a suitable alternative. However, the effectiveness of hydroponic screening methods needs to be verified under the soil condition of the field or pot. In the present study, root traits and NUE were investigated in 19 genotypes under two conditions (hydroponic and pipe filled with soil). Both environments revealed large variability for root traits and NUE under high and low N conditions establishing the absence of any direct selection for these traits in the past. Under both sets of experimentation, NUpE was largely responsible for improved nitrogen efficiency mainly because of higher root biomass. The significant association between the two screening methods i.e. hydroponic and pot filled with soil under both low and high N condition support large scale screening for root traits under hydroponic condition. 相似文献