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291.
对越南发展玉米的自然条件、玉米发展历程和国家育种、栽培及今后的发展方向进行了介绍和分析,以期为我国开展玉米产业的国际合作提供借鉴. 相似文献
292.
293.
黄瓜早熟及丰产性与主要农艺性状的相关性分析 总被引:6,自引:0,他引:6
通过对黄瓜杂种一代苗期及成株33个性状的性状值、超中优势、超亲优势进行了全面系统地研究,分析了黄瓜丰产及早熟两个性状的主要构成因素及与其他性状间的相关性。结果表明,总瓜条数、单瓜重、主枝瓜重量、主枝单瓜重、主枝瓜条数、侧枝瓜条数、侧枝单瓜重、侧枝瓜重量、茎粗和生育天数等性状是决定总产量最为重要的因素并具有较强的杂种优势,无论在性状值、超亲还是超中优势中均达到极显著相关。前期产量主要决定于第一雌花节位和雌花节率及主侧枝瓜条数和瓜重、株高、叶面积等性状,达到显著水平,其中第一雌花节位和雌花节率在性状值、超亲和超中优势中都呈极显著相关性,说明这两个性状是决定黄瓜早熟性的决定性的因素并具有较强的杂种优势。根据试验结果分析了在黄瓜育种和生产过程中为达到早熟高产目的应当注意的几个主要问题。 相似文献
294.
[目的]提取新疆产地的迪西型鹰嘴豆的油脂,测定脂肪酸含量及组分,并测定迪西型鹰嘴豆的分级蛋白和蛋白质氨基酸组成。[方法]以新疆产地的迪西型鹰嘴豆为试验材料,提取其种仁油脂。用气相色谱一质谱法测定脂肪酸的含量及组分;采用微量定氮法和分级提取法测定粗蛋白和分离蛋白,并对蛋白质中的氨基酸组成进行了分析。[结果]鹰嘴豆中油脂含量高(18.2%),油脂以不饱和脂肪酸油酸、亚油酸为主要成分。占脂肪酸总量80%以上,饱和脂肪酸含量较低。鹰嘴豆中粗蛋白质含量平均为23.71%,以球蛋白和清蛋白为主,占蛋白质总量的80%以上,而谷蛋白、醇溶蛋白含量较低。其蛋白质均舍18种氨酸酸,属完全蛋白质。谷氨酸含量最高,占蛋白质的15.8%;天冬氨酸含量占10.7%;此外还有精氨酸(9.30%)、亮氨酸(7.56%)和赖氨酸(6.34%);其次为苯丙氨酸、丙氨酸、缬氨酸、异亮氨酸;色氮酸、蛋氨酸和胱氨酸含量最少。鹰嘴豆中必需氨基酸含量丰富。[结论]新疆迪西型鹰嘴豆是一种不饱和脂肪酸含量很高;氨基酸含量丰富的豆类作物。 相似文献
295.
The aim of this study is to develop new pattern denim fabrics and characterize the mechanical properties of these fabrics after abrasion load. Furthermore, tensile and tear strengths of these fabrics have been analysed by using the Artificial Neural Network (ANN) and statistical model. All denim fabrics were first abraded and subsequently tensile and tearing tests were applied to the abraided fabrics seperately. Actual data generated from the tests were analyzed by ANN and regression model. The regression model has shown that tensile strength properties of the abraded large structural pattern denim fabrics are generally low compared to that of the small structural pattern and traditional denim fabrics. On the other hand, when the abrasion cycles are increased tensile properties of all denim fabrics are generally decreased. Tearing strength of weft and warp in the abraded large structural pattern denim fabrics are between small structural pattern and traditional denim fabric. On the other hand, when the abrasion cycles are increased tearing strength properties in the weft and warp for all denim fabrics are generally decreased. The results from ANN and regression models were also compared with the measured values. It is concluded that almost all values from ANN are accurately predicted compared with those of the regression model. Therefore, we suggest that both methods can be used in this study as viable and reliable tools. 相似文献
296.
In this study, the tensile and tearing properties of substrate, substrate with adhesive and flocked fabric were studied with
developed regression model which explains the relationships between fabric forms and tensile and tearing strength of the flocked
fabrics. Warp and weft tensile strengths of wet flocked fabric are generally higher than the warp and weft tensile strengths
of dry flocked fabric due to the high wet properties of cotton yarn. Weft tensile elongation of the flocked fabric is generally
higher than warp tensile elongation due to the higher crimp ratio of the flocked fabric in the weft direction. Warp and weft
tearing strengths of wet form substrate with adhesive and flocked fabric are higher than those of dry forms of substrate with
adhesive and flocked fabric. One of the reasons could be the decrease of inter-yarn frictional forces due to the lubrication
effect of the wet form of acrylic adhesive in substrate with adhesive fabric. Generally, tearing strength of flocked fabric
is low compared with substrate. It was concluded that the regression model used in this study could be viable and reliable
tools and flocked fabric could be considered as an alternative seat cover material to use in automotive industry. 相似文献
297.
Abbas Nasehi Jugah-Bin Kadir Mehdi Nasr-Esfahani Farnaz Abed-Ashtiani Mui-Yun Wong Siti-Khadijah Rambe Elham Golkhandan 《European journal of plant pathology / European Foundation for Plant Pathology》2014,140(2):261-273
Stemphylium lycopersici (Enjoji) W. Yamam was initially described from tomato and has been reported to infect different hosts worldwide. Sequence analyses of the internal transcribed spacer (ITS) regions 1 and 2, including 5.8S rDNA (ITS-5.8S rDNA) and glyceraldehyde-3-phosphate dehydrogenase (gpd) gene, random amplified polymorphic DNA (RAPD) and inter-simple sequence repeat (ISSR), as well as virulence studies were conducted to analyze 46?S. lycopersici isolates. Stemphylium lycopersici isolates used in this study were obtained from diseased tomato (Solanum lycopersicum L.), eggplant (Solanum melongena L.), pepper (Capsicum annuum L.) and lettuce (Lactuca sativa L.) from major vegetable growing regions of Malaysia, including the three states of Pahang, Johor and Selangor between 2011 and 2012. Phylogenetic analysis of a combined dataset of the ITS-5.8S rDNA and gpd regions indicated that all isolates were clustered in the sub-cluster that comprised S. lycopersici, and were distinguished from other Stemphylium species. Cluster analyses using the UPGMA method for both RAPD and ISSR markers grouped S. lycopersici isolates into three main clusters with similarity index values of 67 and 68 %. The genetic diversity data confirmed that isolates of S. lycopersici are in concordance to host plants, and not geographical origin of the isolates. All S. lycopersici isolates were pathogenic on their original host plants and showed leaf spot symptoms; however, virulence variability was observed among the isolates. In cross-inoculation assays, the representative isolates were able to cause leaf spot symptoms on eggplant, pepper, lettuce and tomato, but not on cabbage. 相似文献
298.
甜瓜高代自交系4G21抗蔓枯病基因的分子定位 总被引:2,自引:0,他引:2
以甜瓜杂交组合4G21 × 3A832的F1、F3家系、BCs和BCr及其双亲为材料,分析了甜瓜蔓枯病抗源4G21的抗性遗传规律。结果表明:F1抗性水平低于抗病亲本,说明抗病基因在F1表现为不完全显性;BCs抗感分离比为1∶1,F3家系抗感分离比为3∶1,说明抗源4G21对蔓枯病的抗性由一对不完全显性基因控制。将该基因命名为Sb-x,定位于甜瓜基因组分子图谱LG1连锁群上,与其两侧的SRAP标记位点me45em42-4、me45em2-3、me45em2-4和me3em42-4、me3em42-3紧密连锁,其遗传距离分别为2 cM和3 cM。 相似文献
299.
2008年5月至2009年2月,采用野外调查、收集标本鉴定和查阅文献方法,对鸡公山药用植物资源种类、分布进行调查。结果表明鸡公山有野生木本药用植物41科138种,并提出资源保护建议。 相似文献
300.
响应面优化苹果皮渣多酚超声提取工艺研究 总被引:4,自引:0,他引:4
【目的】研究超声波辅助乙醇提取苹果皮渣多酚的最佳工艺条件。【方法】以工厂榨汁后的苹果皮渣为原料,在单因素试验的基础上,选取提取时间、超声功率、提取温度、料液比为自变量,多酚的提取率为响应值,根据响应面Box-Benhnken试验设计原理,采用四因子三水平的分析法模拟得到二次多项式回归方程的预测模型,优化苹果皮渣多酚超声提取工艺。【结果】回归模型具有高度显著性,方程对试验拟合较好,可以对苹果皮渣多酚得率进行很好的分析和预测;各因子对提取率的影响大小依次是提取温度>料液比>提取功率>提取时间;响应面分析图表明提取时间和超声功率交互作用不显著,提取温度和超声功率交互作用极显著,料液比的主效应大于温度;超声波辅助乙醇提取苹果皮渣的最佳工艺条件为超声时间10 min,提取温度65℃,超声功率503 W,料液比1﹕30。【结论】多酚的提取率达4.53 mg•g-1,与预测值4.55 mg•g-1基本一致。 相似文献