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61.
The aim of this research was to improve our understanding of how ploidy level influences phenotype and gene expression in Chinese cabbage (Brassica rapa L. ssp. pekinensis). Haploid plants (2n = 10) was induced by 0.2% colchicine to produce diploid (2n = 20) and tetraploid plants (2n = 40). The aneuploid (2n = 24) was also obtained by hybridization between diploid plants as the female and tetraploid plants. The ploidy levels of all plants were identified through chromosome counts and flow cytometry. Leaves and petals became larger as the ploidy level increased from haploid to diploid, and from aneuploid to tetraploid. Similarly, expression of ARGOS was regulated by genome size, increasing in parallel with the level of ploidy. Among the four ploidy types, expression was stronger in the floral buds than in the leaves. Expression by ASY1 also differed according to ploidy level, being highest in diploid plants, followed in order by tetraploids. Expression was similar between haploids and aneuploids at two stages—prior to and after meiosis—but was higher in the haploids during meiosis. When buds were compared within the same ploidy type at different stages, ASY1 expression was obviously higher during meiosis than either before or after. Our study demonstrated the generation and phenotype of a ploidy Chinese cabbage series derived from one haploid. Expression of genes ARGOS and ASY1 were modulated by genome size in this ploidy series, and the regulated patterns of the two genes was different.  相似文献   
62.
中国古老月季品种的核型研究   总被引:4,自引:0,他引:4  
采用常规压片法对‘月月红’等11个中国古老月季品种进行了以染色体形态和倍性为主的核型分析研究。结果表明: (1) 不同品种的染色体数差异较大, ‘绿萼’、‘玉玲珑’、‘月月红’和‘月月粉’是二倍体(2n = 2x = 14) ; ‘春水绿波’和‘湖中月’是三倍体( 2n = 3x = 21) , ‘大富贵’、‘金粉莲’、‘菊红潮’、‘映日荷花’和‘思春’是四倍体(2n = 4x = 28) 。(2) 11个品种染色体的绝对长度均在1~3μm之间; 品种间核不对称系数变化范围为56.560% ~60.376%; 除‘思春’和‘映日荷花’外,其它9个品种中均未观察到随体存在。(3) ‘春水绿波’和‘湖中月’的核型公式为2n = 3x = 21 = 3 sm +18m, 核型类型均是1A; ‘金粉莲’和‘菊红潮’的核型公式为2n = 4x = 28 = 4 sm + 24m, ‘大富贵’的核型公式为2n = 4x = 28 = 2 sm + 26m, 核型类型都是1A; ‘绿萼’的核型公式是2n = 2x = 14 = 2 sm + 12m, 核型类型为1B; ‘思春’和‘映日荷花’的核型公式是2n = 4x = 28 = 4 sm + 22m + 2m ( SAT) , 核型类型为1A; ‘玉玲珑’的核型公式是2n = 2x = 14 = 2 sm + 12m, 核型类型为1A; ‘月月粉’和‘月月红’的核型公式是2n = 2x = 4 sm + 10m, 核型类型为2A。  相似文献   
63.
辣椒花药培养再生植株染色体倍数检测研究   总被引:2,自引:0,他引:2  
采用流式细胞仪(FCM)对7个甜椒F1和3个辣椒F1的花药培养的再生株,在幼苗期进行了倍性鉴定.流式细胞仪的矩形图中清楚显示出每份材料叶片的DNA含量,即检测出单倍体、二倍体、三倍体或单倍体加二倍体的混倍体.研究表明:辣椒花药培养再生株中,单倍体和二倍体比率约为70.91%、25.45%.流式细胞仪可以快速且准确的检测出试材的染色体倍性,与座果结子的鉴别结果相一致.本文还讨论了采用流式细胞仪的优势以及存在的问题.  相似文献   
64.
以经秋水仙碱诱导获得的银杏大花粉为材料,以未经处理的正常银杏花粉为对照,利用扫描电子显微镜和激光扫描共聚焦显微镜分别观察2种花粉表面形态,并分析对比其细胞内的DNA相对荧光量与银杏大花粉核内染色体倍性关系,为正确检出银杏二倍体花粉奠定重要工作基础。研究结果表明,此方法用于花粉粒的倍性鉴定科学准确,所需试验样本少,实用性强,在植物花粉倍性鉴定中有着较好的应用前景。   相似文献   
65.
  • 1. Carassius auratus, a primary freshwater fish with bisexual diploid and unisexual gynogenetic triploid lineages, is distributed widely in and around the Eurasian continent and is especially common in East Asia. East Asian C. auratus diverged genetically to form local endemic populations in different regions, and those distributed in the Ryukyu Archipelago form a local endemic population that can be regarded as an evolutionarily significant unit because of its high phylogenetic independence and evolutionary distinctiveness. Although the evolutionary uniqueness of this population should be conserved, its distribution area and population size are decreasing rapidly, and some island populations are currently considered endangered or already extinct.
  • 2. To develop effective conservation measures to stop the current decline of Ryukyuan C. auratus, ecological data need to be collected. In this study, life history data for a C. auratus population distributed in the Hiji River system were collected by estimating age, growth, and spawning season.
  • 3. The spawning season of C. auratus in the Hiji River extended from March to September, peaking during March–May. Females became sexually mature in their second year, but males reached maturity and were able to spawn as early as in the late spawning season of their year of hatching. Once having reached sexual maturity, males probably continuously stay ripe throughout their life.
  • 4. Sagittal otoliths of C. auratus proved to be useful ageing structures because one annual increment is formed on the sagittal otolith before the spawning season in each year. The oldest fish observed were a 10‐year‐old female and an 11‐year‐old male. Females showed faster somatic growth and higher final standard length than males, and a sexual size dimorphism was observed.
  • 5. The standard length at each age class did not differ between diploid and triploid C. auratus, suggesting that triploid growth rates were almost equal to those of diploids. Copyright © 2009 John Wiley & Sons, Ltd.
  相似文献   
66.
【目的】以单胚性的二倍体柑橘品种为母本与异源四倍体体细胞杂种杂交培育三倍体植株。【方法】选择亲本配置杂交组合进行人工授粉,授粉后70—100 d采幼果进行胚挽救,以流式细胞仪结合根尖染色体压片对再生植株进行倍性检测,最后进行SSR分子标记鉴定。【结果】2009—2012连续4年,以8个二倍体为母本、以4个异源四倍体体细胞杂种为父本,共配置14个倍性杂交组合,授粉花数3 347朵,坐果数678个,平均坐果率20.26%。实施胚挽救的果实数505个,培养种子12 357粒,经生芽、生根诱导培养共获得1 022个株系。通过对再生植株的倍性检测,共获得三倍体植株755个株系,四倍体19个株系。对华农红柚 × NH组合的三倍体、四倍体后代进行分子鉴定,表明三倍体和四倍体全部为双亲的有性杂种后代。【结论】本研究通过杂交获得的三倍体为我国无籽柑橘品种选育奠定了材料基础;同时获得的四倍体后代也为未来的柑橘三倍体育种提供了优良的亲本材料。  相似文献   
67.
洞庭湖水域不同倍性野生鲫的血液相关特点   总被引:1,自引:0,他引:1  
邹拓谜  肖俊  刘少军  赵如榕  张纯  陶敏  颜金鹏  刘筠 《水产学报》2011,35(10):1488-1493
对洞庭湖水域野生鲫群体中同时存在的二倍体(2n=100)、三倍体(3n=150±)和四倍体(4n=200)野生鲫血液相关特点进行研究。通过流式细胞仪检测野生鲫倍性,将不同倍性野生鲫进行血细胞涂片观察,使用全自动血液分析仪检测不同倍性野生鲫血红蛋白含量。结果发现,3种不同倍性野生鲫血细胞大小与倍性成正比,且能在三倍体和四倍体野生鲫血细胞中观察到一定数量的由无丝分裂所导致的哑铃型细胞核的存在;同时3种不同倍性野生鲫血红蛋白含量没有明显区别。根据这些结果推测,两种高倍性的野生鲫很可能是通过血细胞的无丝分裂来增加细胞数量,保证其总血红蛋白含量相对稳定,从而进一步保证它们运输氧气的能力。  相似文献   
68.
I. Ho    Y. Wan    J. M. Widholm  A. L. Rayburn 《Plant Breeding》1990,105(3):203-210
The usefulness of using the chloroplast number in epidermal guard cells as an indirect ploidy indicator was evaluated on seed-grown and tissue culture-derived maize plants. For seed-grown plants, two maize genotypes (B89 and R75) which had both diploid and tetraploid seeds available were used as experimental materials. The ploidy levels of seed-grown plants were confirmed by flow cytometric analysis of nuclear suspensions from these plants. For regenerated plants, haploid and diploid levels were examined and the ploidy levels of these plants were determined by chromosome counts of cells from root tips. A positive relationship between the chloroplast number and ploidy level was observed for both seed-grown and regenerated plants. The stomatal guard cells of tetraploid plants had nearly double the number of chloroplasts as the diploid plants. Similar results were found from the regenerated plants. The differences in the mean chloroplast number between diploid and tetraploid seed-grown plants and between haploid and diploid regenerated plants were highly significant. The results of this study demonstrate that counting chloroplasts in guard cells can be an efficient means of screening a large number of plants for ploidy levels. In addition, this study suggests the possibilities of using this method for detecting contaminated seed lots by different ploidy seed and for distinguishing plants of different genotypes.  相似文献   
69.
鸢尾属植物育种研究进展   总被引:2,自引:0,他引:2  
对近年来国内外有髯类鸢尾和无髯类鸢尾育种研究的进展和成果进行了综述。针对我国鸢尾属植物育种现状提出了见解并作出了展望,旨在推动我国鸢尾育种研究的进程。  相似文献   
70.
植物细胞染色体倍性鉴定方法   总被引:16,自引:0,他引:16  
综述了植物细胞染色体倍性鉴定的染色体计数法、流式细胞分析法、检测气孔大小及气孔保卫细胞叶绿体数目法等各种检测方法 ,并对其优缺点进行了评述  相似文献   
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