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61.
在结合参考1990年以来三明全市名木古树调查、各自然保护区植被调查的基础上,对1999年至2001年全市各县区珍稀野生植物资源调查资料进行市级汇总,得出52个目的物种资源调查结果,并通过分析评价其资源现状,提出结论与建议。  相似文献   
62.
秦岭山区10种野生植物的园林利用价值   总被引:3,自引:1,他引:3  
以园林观赏为目的,结合资料查阅和野外调查,从秦岭山区分布的野生植物中选取了唐棣、紫斑牡丹、陕西荚、流苏、山梅花、山丹花、中华秋海棠、秦岭翠雀花、紫斑风铃和乌头草等10种观赏价值较高的野生植物,介绍了其分布、生态要求和观赏价值,为进一步开展引种驯化和品种选育奠定了基础。  相似文献   
63.
Use of crystalline methionine to optimize amino acid profiles in feeds for Atlantic salmon (Salmo salar L.) was studied in three experiments. A basic experimental diet with 25% of dietary protein from marine origin and the remaining 75% from soya protein concentrate was used either with or without supplementation of L ‐methionine, D ‐methionine or DL ‐methionine. A fishmeal‐based diet was used as control. In experiment 1, growth performance of 100 g salmon in seawater was improved by supplementation with the different methionine products. Growth performance was, however, inferior to that of fish fed the control. Feed conversion ratios (FCR) exhibited similar trends to specific growth rate (SGR) with methionine supplementation, but again not as the control. Protein retention, measured as productive protein value (PPV), was significantly better in the control and D ‐methionine groups as compared with either L ‐methionine or the nonsupplemented group. These trends were confirmed in experiment 2, using fish of the same size, where an absorption and digestibility study of D ‐ and L ‐methionine clearly indicated that D ‐methionine was absorbed as well as L ‐methionine. Results indicated that racemization of D ‐ into L ‐methionine occurs in liver and kidney in Atlantic salmon. Ornithine decarboxylase (ODC) activity in liver was significantly affected by dietary treatment and there was a good correlation with growth and feed utilization data. In experiment 3, a growth study with large salmon (1 kg) was performed using increasing supplementation of DL ‐methionine to the basic diet. Results indicated a methionine requirement for maximum growth of 9.2 g kg–1 feed dry matter (DM) kg–1 growth. This is slightly higher than that reported in the literature. The present study clearly shows that optimizing the amino acid profile by inclusion of a single crystalline amino acid (crystalline methionine) does not give the same protein utilization as that of a diet in which the amino acids are mainly protein bound. D ‐methionine was found to result in better protein utilization than L ‐methionine when measured as PPV.  相似文献   
64.
内蒙古桦木沟林场地形地貌类型广泛,野花资源丰富,尚未得到有效开发。为了解野生花卉资源习性和生物学特征,开发利用野花资源,在路径调查的基础上,采用典型样地调查法,调查分析了其野花资源分布。共调查野花资源177种,隶属于40科129属,菊科、豆科、毛茛科等种类和种群数量较丰富。不同地貌Margalef丰富度指数1.35~8.28,Shannon-Wiener指数变异范围1.42~2.59,Simpson指数为0.59~0.96,湿地草甸、疏林草地物种多样性丰富,沙地多样性最低。湿度、光照等是影响野花多样性分布的重要因素。林场分布着丰富而有较大开发价值的喜光、耐荫、耐涝、喜湿、耐旱等不同生态型野生花卉。部分野生花卉资源濒危,亟需保护。  相似文献   
65.
为对野果资源的食用开发提供评价和筛选依据,应用层次分析法构建野果资源食用开发价值综合评价模型,并对浙江大盘山国家级自然保护区常见的40种可食用野果进行评价和筛选。结果表明,野果资源食用开发价值的标准层指标的综合权重值为风味口感(0.2674)>营养保健(0.1245)>贮藏难度(0.0884)>结果产量(0.0733)>适应能力(0.0658)>驯化技术(0.0658)>观赏价值(0.0590)>资源储量(0.0442)=新颖程度(0.0442)>产品卖相(0.0368)=食用风险(0.0368)>繁育特性(0.0329)>采食时间(0.0314)>药用价值(0.0295)。经筛选,三叶木通(Akebia trifoliata)、南五味子(Kadsura japonica)、蓬蘽(Rubus hirsutus)等5种野果被评为I级开发利用对象;插田泡(Rubus coreanus)、木通(Akebia quinata)、中华猕猴桃(Actinidia chinensis)等14种野果被评为II级开发利用对象;北枳椇(Hovenia dulcis)、君迁子(Diospyros lotus)、珍珠栗(Castanea henryi)等9种野果被评为III级开发利用对象;高梁泡(Rubus lambertianus)、野山楂(Crataegus cuneata)、山樱花(Cerasus serrulata)等12种野果被评为IV级开发利用对象。  相似文献   
66.
云南野生茶树的地理分布及形态多样性   总被引:2,自引:4,他引:2  
云南是世界茶树的原产地和起源中心,茶树种质资源种类众多,遗传多样性丰富,在茶学研究中占有非常重要地位。通过野外调查与文献资料的整理,对云南野生茶树资源的地理分布和形态多样性进行了调查,结果显示:(1)野生茶树在云南分布广泛,主要集中在西双版纳、普洱、保山等8个地区;(2)野生茶树与栽培茶树在形态上有明显差异;(3)云南野生茶树在形态分类上有22个种和2个变种,野生茶树呈现丰富形态多样性;(4)生境破坏是导致野生茶树数量锐减的主要原因,建议今后应加强珍稀濒危野生茶树种质的调查、收集保存、生态型及遗传多样性的研究和利用,为促进茶树新品种选育及茶产业可持续发展提供丰富的资源技术基础。  相似文献   
67.
Few genes are available to develop drought-tolerant bread wheat (Triticum aestivum L.) cultivars. One way to enhance bread wheat’s genetic diversity would be to take advantage of the diversity of wild species by creating synthetic hexaploid wheat (SW) with the genomic constitution of bread wheat. In this study, we compared the expression of traits encoded at different ploidy levels and evaluated the applicability of Aegilops tauschii drought-related traits using 33 Ae. tauschii accessions along with their corresponding SW lines under well-watered and drought conditions. We found wide variation in Ae. tauschii, and even wider variation in the SW lines. Some SW lines were more drought-tolerant than the standard cultivar Cham 6. Aegilops tauschii from some regions gave better performing SW lines. The traits of Ae. tauschii were not significantly correlated with their corresponding SW lines, indicating that the traits expressed in wild diploid relatives of wheat may not predict the traits that will be expressed in SW lines derived from them. We suggest that, regardless of the adaptability and performance of the Ae. tauschii under drought, production of SW could probably result in genotypes with enhanced trait expression due to gene interactions, and that the traits of the synthetic should be evaluated in hexaploid level.  相似文献   
68.
为比较人工养殖大刺鳅与野生大刺鳅肌肉脂肪酸组成的差异,采用气相色谱分析法对养殖和野生大刺鳅幼鱼、鱼种、成鱼肌肉脂肪酸组成及其相对含量进行了检测与分析。结果表明,养殖和野生大刺鳅肌肉中共检出24种脂肪酸,其中不饱和脂肪酸含量较均最高,平均含量分别达到(65.63±1.88)%和(59.03±2.11)%,特别是含有丰富的C18:2、二十二碳六烯酸、二十碳五烯酸和 ,花生四烯酸等多不饱和脂肪酸;ΣUFA/ΣSFA比值从幼鱼到成鱼阶段显上升趋势,且养殖大刺鳅(2.45±0.21)高于野生大刺鳅(1.98±0.15);养殖大刺鳅成鱼阶段的P/S比值达到1.0,超过一般的淡水鱼类。综合分析表明,养殖大刺鳅肌肉品质在脂肪酸组成及均衡性略优于野生大刺鳅,但差异不明显。  相似文献   
69.
Vernalization insensitivity is a key feature of domesticated chickpea, and its genetic basis is not well understood. We studied vernalization response among hybrid progeny derived from two domesticated × wild crosses. The wild parents are vernalization‐sensitive, late‐flowering genotypes while both domesticated parents are vernalization insensitive. Parental lines and hybrid progeny were tested with (28 days at 4°C) and without vernalization (control). The difference in mean days to flower (?DTF) between control and vernalization treatments was used to assess the flowering vernalization response. A wide range of ?DTF values was observed among the hybrid progeny. Strong genotype by environment interaction effect on ?DTF was observed for the parental accessions and hybrid progeny. We used the ?DTF values to select vernalization responsive and non‐responsive progeny lines. However, the genotype × environment interaction strongly interfered with our selection. Chickpea breeders interested in using the wild progenitor as a donor of exotic traits should be aware of the possibility of introducing vernalization response alleles that may alter the phenology of their breeding materials in an unpredictable manner.  相似文献   
70.
The objective of this study was to identify quantitative trait loci (QTLs) controlling 100‐seed weight in soybean using 188 recombinant inbred lines (RIL) derived from a cross of PI 483463 and ‘Hutcheson’. The parents and RILs were grown for 4 years (2010–2013), and mature, dry seeds were used for 100‐seed weight measurement. The variance components of genotype (a), environment (e) and a × e interactions for seed weight were highly significant. The QTL analysis identified 14 QTLs explaining 3.83–12.23% of the total phenotypic variation. One of the QTLs, qSW17‐2, was found to be the stable QTL, being identified in all the environments with high phenotypic variation as compared to the other QTLs. Of the 14 QTLs, 10 QTLs showed colocalization with the seed weight QTLs identified in earlier reports, and four QTLs, qSW5‐1, qSW14‐1, qSW15‐1 and qSW15‐2, found to be the novel QTLs. A two‐dimensional genome scan revealed 11 pairs of epistatic QTLs across 11 chromosomes. The QTLs identified in this study may be useful in genetic improvement of soybean seed weight.  相似文献   
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