微卫星标记多态性及其与湖北白鹅肌肉肌苷酸含量的相关分析

[目的]为湖北白鹅肉质性状的间接选择提供参考依据。[方法]采用聚丙烯酰胺凝胶电泳（PAGE）检测湖北白鹅基因组DNA8个微卫星标记多态性,计算基因频率（P）、平均基因杂合度（H）、多态信息含量（PIC）,分析白鹅性别、日龄及基因型与肌肉肌苷酸含量的相关性。[结果]所检测的8个微卫星座位的平均等位基因数为2．75个,H为0．5945,PIC为0．5087。56日龄鹅肉样肌苷酸含量为（1360．25±82．56）mg／g,显著高于180日龄鹅肉样肌苷酸含量（1088．07±63．56）mg／g。所检测的8个微卫星座位,ADL166座位AA基因型、ADL210座位AA与BC基因型、MCW0104座位AB与BC基因型、MCW264座位AA基因型、MCW0085座位AA与BB基因型、MCW0004基因座BC基因型、MCW0120座位AC基因型、MCW0014座位AA基因型个体的肌肉肌苷酸含量较高。[结论]这些微卫星标记有望作为遗传标记对鹅的肉质性状进行标记辅助选择。     

甜叶菊微卫星富集文库的构建与多态性标记的筛选

甜叶菊是我国一种重要特种经济作物, 其分子标记相关遗传背景研究甚少。本研究基于生物素与链霉亲和素的强亲和性原理, 用链霉亲和素顺磁颗粒捕捉人工合成的标记有生物素的寡核苷酸探针(AG)₁₅, 间接筛选出含有甜叶菊基因组微卫星序列的DNA酶切片段, 将筛选得到的片段连接到pUC-T载体中, 构建甜叶菊微卫星序列的富集文库。挑取354个克隆进行菌落PCR检验, 从中筛选出158个阳性克隆进行测序。结果表明, 134个(84.81%)克隆中含有微卫星序列, 其中完美型85个(63.43%)、非完美型15个(11.19%)、复合型34个(25.38%)。根据微卫星序列共设计出71对微卫星引物, 其中62对能扩增出稳定的条带。利用24个甜叶菊品系对这62对引物的遗传多样性的分析表明, 有16个位点表现出多态性, 等位基因数为2~8个, 平均每个位点扩增得到4.5个等位基因, 多态性信息含量在0.3163~0.7595之间, 观测杂合度(H_o)与期望杂合度(H_e)的范围分别为0.2174~0.9167与0.3555~0.8076。通过聚类分析, 将甜叶菊分为大小叶两大类。本研究开发出的微卫星标记可为甜叶菊的分子遗传育种提供有效的遗传标记。     

Plastid DNA variation in Prunus serotina var. serotina (Rosaceae), a North American tree invading Europe

Black cherry (Prunus serotina) is a tree from North America, where it is often used for economical purposes, whereas it is widespread and invasive in Europe. Plastid DNA variation was first investigated in both its native and invasive ranges using microsatellite loci and sequences of three intergenic spacers (trnT-trnL, trnD-trnT and trnS-trnG). This analysis was focused on P. serotina var. serotina, with the inclusion of samples of closely related taxa. Length variation at a microsatellite locus (ccmp5) and a few sequence polymorphisms were identified among P. serotina samples. Four new primer pairs were then designed to specifically amplify variable regions and a combination of five markers was finally proposed for phylogeographic studies in P. serotina. These loci allow identification of six chlorotypes in P. serotina var. serotina, which may be particularly useful to depict the maternal origins of European invasive populations.     

A practical method for almond cultivar identification and parental analysis using simple sequence repeat markers

Early and accurate identification of almond [Prunus dulcis (Mill.) D.A. Webb] cultivars is critical to commercial growers and nurseries. Previously published simple sequence repeat loci were examined for their ability to distinguish commonly grown almond cultivars. Twelve highly polymorphic loci were selected for their ability to uniquely identify a set of 18 almond cultivars commonly grown in California, many of which are closely related. These markers also allow an accurate assessment of parent/progeny relationships among cultivars. This system can reliably identify at an early stage of development all major California almond cultivars in current production.     

Mapping QTLs for pre-harvest sprouting traits in the spring wheat cross ‘RL4452/AC Domain’

Pre-harvest sprouting (PHS) in spring wheat (Triticum aestivum L.) is a major downgrading factors for grain producers and can significantly reduce end-use quality. PHS resistance is a complex trait influenced by genotype, environment and plant morphological factors. A population of 185 doubled haploid (DH) lines from the spring wheat cross ‘RL4452/AC Domain’ were used as the mapping population to detect quantitative trait loci (QTLs) associated with three PHS traits, germination index (GI), sprouting index (SI) and falling number (FN). Six major QTLs linked with PHS traits were mapped on bread wheat chromosomes 3A, 3D, 4A (2 loci), 4B and 7D. ‘AC Domain’ alleles contributed to PHS resistance on 3A, 4A (locus-2) and 4B, and ‘RL4452’ alleles contributed resistance on 3D, 4A (locus-1) and 7D. QTLs detected on chromosome 4B controlling FN (QFN.crc-4B), GI (QGI.crc-4B) and SI (QSI.crc-4B) were coincident, and explained the largest amount of phenotypic variation in FN (22%), GI (67%) and SI (26%), respectively.     

Different quantitative trait loci for <Emphasis Type="Italic">Fusarium</Emphasis> resistance in wheat seedlings and adult stage in the Wuhan/Nyubai wheat population

Fusarium head blight (FHB), caused primarily by Fusarium graminearum (Schwabe), is an important wheat disease. In addition to head blight, F. graminearum also causes Fusarium seedling blight (FSB) and produces the mycotoxin deoxynivalenol (DON) in the grain. The objectives of this study were: (1) to compare the relationship between resistance of wheat lines to F. graminearum in the seedlings and spikes and (2) to determine whether the quantitative trait loci (QTL) for FSB were the same as QTLs for FHB resistance and DON level reported for the same population previously (Somers et al. 2003). There was no relationship between FSB infection and FHB index or DON content across the population. A single QTL on chromosome 5B that controlled FSB resistance was identified in the population; the marker WMC75 explained 13.8% of the phenotypic variation for FSB. This value implies that there may be other QTL with minor effects present, but they were not detected in the analysis. Such a QTL on chromosome 5B was not reported previously among the QTLs associated with FHB resistance and DON level in this population. However, because of recombination, some lines in the present study have Fusarium resistance for both seedling and head blight simultaneously. For example, DH line HC 450 had the highest level of resistance to FSB and FHB and was among the ten lines with lowest DON content. This line is a good candidate to be used as a parent for future crosses in breeding for Fusarium seedling resistance, together with breeding for head blight resistance. This approach may be effective in increasing overall plant resistance to Fusarium.     

High levels of pollen dispersal detected through paternity analysis from a continuous Symphonia globulifera population in the Brazilian Amazon

In this study, six highly polymorphic microsatellite loci and a categorical paternity analysis approach were used to investigate the contemporary pollen gene flow in the neotropical tree species Symphonia globulifera. Data for this study were taken from a 500 ha experimental plot in a dense terra firme forest in the Eastern Brazilian Amazon and included the mapping and genotyping of 161 reproductive trees, representing more than 90% of all adult trees, and the collection of 748 open-pollinated seeds from 56 seed-trees over two field seasons (2002 and 2003). High levels of pollen immigration from outside of the study plot were detected in both sampled seed-years (≥49%) suggesting long distance pollen gene flow. Low levels of self-fertilization were also detected (≤2%). The analysis showed long distance pollen dispersal occurred within the study area in both 2002 (δ = 907 ± 652 m SD) and 2003 (δ = 963 ± 542 m SD). Patterns of pollen dispersal distance within the plot were also found to be shorter than the distances between potential male parents and seed-trees. This result indicates that the distance between trees does not explain the identified pollen dispersal pattern. Our results support the hypothesis that animal pollinated species occurring in low-density populations can disperse pollen in long distances, despite the very dense nature of the forest.     

蒙古驴微卫星多态性分析

利用10对微卫星引物对94头蒙古驴进行DNA多态性分析,主要研究了有效等位基因数、多态信息含量和杂合度等指标.结果表明:10个微卫星位点中,HTG7、HTG10、AHT4、HTG6、HMS6、HMS3共6个位点具有高度多态性(PIC＞0.5),HMS7位点具有中度多态性,其等位基因数、有效等位基因数、多态信息含量、杂合度最低.其余3个微卫星座位(HMS1,HTG4和HMS5)为单态,没有多态性.总体上看,蒙古驴的遗传多态性很高,有利于遗传资源的开发与利用.     

文昌鸡群体内遗传变异分析

利用17个微卫星位点对海南文昌鸡群体内的遗传变异情况进行了分析,结果表明,13个位点处于哈代-温伯格平衡状态,2个位点处于不平衡状态,2个位点处于极不平衡状态。文昌鸡群体内平均杂合度(H)为0.7608;多态信息含量(PIC)为0.6899,平均有效等位基因数(Ne)为5.0254,群体杂合度和多态信息含量都相对较高,说明文昌鸡群体内的遗传变异较大,具有较高的选择潜力。     

鸡微卫星DNA标记与其生长性状的相关分析

测定了固始鸡与安卡鸡杂交后自交F2代500多个个体的0,2,4,6,8,10,12周龄体重,检测10个微卫星DNA标记,对标记基因型生长性状值进行方差分析和多重比较。结果表明:对于2,8,12周龄体重,MCW166各基因型间有显著差异(P<0.05);6周龄体重,MCW166各基因型间有极显著差异(P<0.01);对于2周龄体重,ADL169各基因型间有极显著差异(P<0.01),4,6,8周龄体重,ADL169各基因型间有显著差异(P<0.05)。