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951.
Inheritance mode of microsatellite DNA markers and their use for kinship estimation
in kuruma prawn Penaeus japonicus 总被引:8,自引:0,他引:8
The allelic inheritance mode of microsatellite DNA markers was examined using seven copulated wild females and their offspring. Five microsatellite loci, CSPJ002 *, CSPJ010 *, CSPJ012 *, CSPJ014 *, and CSPJ015 *, were used in the study. At almost all family/locus combinations, one sire was determined and distributions of genotypes in offspring were consistent with the Mendelian segregation ratio. Distributions of genotypes were consistent with the ratio after assuming a null allele at some loci. Consequently, the alleles of CSPJ002 * and CSPJ012 * were inherited following the Mendelian inheritance mode in every family; however, the null allele was expected in CSPJ010 *, CSPJ014 *, and CSPJ015 * in some families. Thus, these loci should be used carefully in population genetic analysis, but siblings could be detected in the dendrograms based on unweighted pair-group method using arithmetic averages (UPMGA). 相似文献
952.
选用荧光标记的19个微卫星DNA标记,通过PCR扩增和ABI3700遗传分析仪基因分型,对贵阳中医学院实验猪场的一个剑白香猪群体进行了遗传多样性研究.结果表明,在19个微卫星位点中,仅S0128位点存在哑等位基因(Null allele),SW951和S0218两个位点极显著地偏离哈德一温伯格平衡,其他位点皆处于哈德-温伯格平衡状态;该剑白香猪实验群体的平均等位基因数、平均多态信息含量和平均期望杂合度分别是3.680、0.452和0.521.在近期内没有发牛过瓶颈效应.并用STRUCTURE软件对所研究的群体进行了群体结构的分析,表明作为实验猪群的剑白香猪群体,虽经多年的培育,仍然保持了较丰富的遗传多样性. 相似文献
953.
Summary Using the finger nails to remove most of the petals is a fast method of preparing apple flowers for hand pollination in the balloon stage. Such flowers still appeared quite attractive to insects; left to open pollination, the seed set per flower averaged two thirds of that of similarly treated, but hand-pollinated flowers. With the aid of marker pollen of scab or mildew resistant donors and the subsequent screening of the seedling progenies for resistance, it was shown that the stray pollen was responsible on average for one of every three seeds formed by unbagged depetalled and hand-pollinated flowers. 相似文献
954.
955.
从转入bar基因的籼稻半矮秆材料9311HR的BC3F2中发现了1株高秆突变体9311HR-T,其株高和秆长分别比野生型9311HR增加60.8%和71.5%,其高秆性状受1对显性基因控制.以9311HR-T与02428杂交产生的F2群体为材料,利用微卫星标记将9311HR-T高秆基因定位在水稻第1染色体长臂上的SSR标记RM472和RM1387之间,距RM472和 RM1387的遗传距离分别为8.6 cM和12.3 cM,该基因暂命名为DT1. 相似文献
956.
YU Xiao-xia ZHAO Ning LI Hui JIE Qin ZHAI Hong HE Shao-zhen LI Qiang LIU Qing-chang 《农业科学学报》2014,13(2):310-315
Sweetpotato (Ipomoea batatas (L.) Lam.) breeding is challenging due to its genetic complexity. In the present study, interval mapping (IM) and multiple quantitative trait locus (QTL) model (MQM) analysis were used to identify QTLs for starch content with a mapping population consisting of 202 F1 individuals of a cross between Xushu 18, a cultivar susceptible to stem nematodes, with high yield and moderate starch, and Xu 781, which is resistant to stem nematodes, has low yield and high starch content. Six QTLs for starch content were mapped on six linkage groups of the Xu 781 map, explaining 9.1-38.8% of the variation. Especially, one of them, DMFN 4, accounted for 38.8% of starch content variation, which is the QTL that explains the highest phenotypic variation detected to date in sweetpotato. All of the six QTLs had a positive effect on the variation of the starch content, which indicated the inheritance derived from the parent Xu 781. Two QTLs for starch content were detected on two linkage groups of the Xushu 18 map, explaining 14.3 and 16.1% of the variation, respectively. They had a negative effect on the variation, indicating the inheritance derived from Xu 781. Seven of eight QTLs were co-localized with a single marker. This is the first report on the development of QTLs co-localized with a single marker in sweetpotato. These QTLs and their co-localized markers may be used in marker-assisted breeding for the starch content of sweetpotato. 相似文献
957.
Genetic diversity and relatedness estimates for captive barramundi (Lates calcarifer,Bloch) broodstock informs efforts to form a base population for selective breeding 下载免费PDF全文
Shannon R Loughnan Carolyn Smith‐Keune Dean R Jerry Luciano B Beheregaray Nicholas A Robinson 《Aquaculture Research》2016,47(11):3570-3584
Aquaculture of barramundi or Asian seabass (Lates calcarifer) is growing in both Australia and Southeast Asia and there is substantial interest to improve production efficiency through selective breeding. The establishment of a large and genetically diverse base population is a prerequisite for a sustainable and long‐term productive breeding program. Before selective breeding programs can begin for Australian barramundi it is important to assess the overall genetic diversity of current captive broodstock populations. To address this question, 407 captive barramundi broodstock from eight separate Australian broodstock populations were genotyped using 16 polymorphic microsatellite DNA markers. A Bayesian STRUCTURE analysis indicated that captive Australian broodstock are broadly divided into two genetic stocks. Multivariate analysis between broodstock individuals and pairwise FST between broodstock populations also supported the existence of two stocks. Comparisons with data obtained from natural stocks suggested that hatchery individuals were either sourced from the two stocks or represented an admixture between them. Genetic diversity was low within each broodstock population (allelic richness ranged from 2.67 to 3.42 and heterozygosity ranged from 0.453 to 0.537) and relatedness estimates within hatcheries were generally low (average r was equal to 0.141). We recommend sourcing captive individuals according to high levels of neutral genetic diversity and low levels of relatedness for the establishment of a base population. We also make recommendations about including genetically diverse wild individuals. 相似文献
958.
竹类植物基因组学研究进展 总被引:1,自引:0,他引:1
概述竹类植物基因组学研究进展,包括RAPD,RFLP,AFLP,ISSR等分子标记的开发与应用,开花、细胞壁生物合成、光合作用、抗逆等相关的重要功能基因研究,基因组测序与比较基因组学等;在分析和综述的基础上,提出竹类植物分子生物学研究基础薄弱、功能基因鉴定困难等不足,并明确遗传转化体系的建立、比较基因组学与功能基因组学研究、分子标记辅助育种是今后竹类植物基因组学研究的重点。 相似文献
959.
选用晋大62×诱处4号杂交亲本和后代群体为试验材料,通过微卫星(SSR)标记分析,利用SPSS软件对其进行了聚类分析,探讨了亲本及后代群体间的遗传特性和亲缘关系,研究了大豆群体的遗传多样性,为大豆杂交育种亲本的选配、杂交后代的筛选、种质创新及大豆遗传多样性研究提供了理论和实践依据。结果表明,以亲本的基因组DNA为模板,选用40对不同的引物进行电泳共筛选出23对位于多条染色体上的差异引物,其多态性比例为55.0%。通过聚类分析所有材料可聚类为以下几类:母本晋大62(CK1)和后代6~13号材料聚为第一大类,父本诱处4号(CK2)和后代25~31号材料聚为第二大类,而1~5、14~20聚为第一小类,21~24、32~35聚为第二小类,这两小类材料与亲本的亲缘关系较远。 相似文献
960.