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101.
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
102.
Quahir Sohail Tomoe Inoue Hiroyuki Tanaka Amin Elsadig Eltayeb Yoshihiro Matsuoka Hisashi Tsujimoto 《Breeding Science》2011,61(4):347-357
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
103.
Vernalization response of domesticated × wild chickpea progeny is subject to strong genotype by environment interaction 下载免费PDF全文
Ruth Pinhasi van‐Oss Amir Sherman Hong‐Bin Zhang George Vandemark Clarice Coyne Shahal Abbo 《Plant Breeding》2016,135(1):102-110
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
104.
Identification of quantitative trait loci controlling soybean seed weight in recombinant inbred lines derived from PI 483463 (Glycine soja) × ‘Hutcheson’ (G. max) 下载免费PDF全文
Krishnanand P. Kulkarni Minsu Kim J. Grover Shannon Jeong‐Dong Lee 《Plant Breeding》2016,135(5):614-620
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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107.
采用柱层析从野玫瑰色素中分离出2个组分,利用纸层析和紫外—可见光谱分析,结合一定的化学方法和有关文献,进行初步鉴定。其中,组分I为纯度较高的花色苷,分别为:芍药色素-3-葡萄糖苷和飞燕草花色素-3-葡萄糖鼠李糖苷;组分Ⅱ推测为黄酮类物质,结构待定。 相似文献
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109.
建立仿生型兰花驯化园的研究 总被引:1,自引:0,他引:1
仿野生兰花的生长环境,选择适宜的林地小气候条件建立兰花驯化园,在不搭荫棚、不搭防雨棚下、使地产兰花在林内安全越冬,既达到了保护野生兰花种质资源和合理开发利用的目的,又节约了建园投资用80%~90%,为山区农民节省耕地、养兰政官提供了一条新门路。 相似文献
110.