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71.
甜瓜结实花初花节位QTL分析   总被引:3,自引:1,他引:2  
朱子成  高美玲  高鹏  栾非时 《园艺学报》2011,38(9):1753-1760
 以WI998为母本(纯雌株、厚皮网纹甜瓜品系),TopMark为父本(雄全同株纯合品系),配置杂交组合,利用单粒传得到171个株系的重组自交系(F2S4)群体构建甜瓜SSR分子标记遗传连锁图谱。该连锁图谱包含19个连锁群,覆盖基因组长度为1 414.2 cM,标记间平均距离为10.2 cM。对结实花初花节位开展QTL分析,共检测到9个QTL,分别分布在第1、9、10、11连锁群上,各QTL的LOD值在2.89 ~ 9.42之间,4个QTL贡献率超过10%。位于第9连锁群的QTL Fp9.4贡献率最大,为18.57%(2010秋季LOD = 9.17);位于第9连锁群的Fp9.3(2010春季8.64%,LOD = 6.44;2010秋季17.99%,LOD = 9.42),位于第10连锁群的Fp10.1(2010春季3.59%,LOD = 2.89;2010秋季6.20%,LOD = 3.43)在两季的位置都很稳定。获得与结实花初花节位紧密连锁(< 10 cM)的8个特异标记(SSR01737、MU141991、TJ105、GCM206、SSR04910、MU173563、NR52、MU146331),为进一步开展QTL精细定位提供参考。  相似文献   
72.
Knowledge of the effects of farmer practices on population genetic parameters of peach palm (Bactris gasipaes Kunth) is relevant to the improvement and conservation of the palm’s genetic resources. Microsatellite markers were used to assess genetic diversity and population structure of peach palm in swidden-fallow agroforestry systems in northeastern Peru. The study covered eight communities, comprising two study areas 160 km apart – one occupied by indigenous Amerindians and the other by mixed race campesinos. Simultaneous analysis of an ex situ peach palm germplasm collection provided a means to compare population genetic parameters. Farmers who were surveyed on seed selection practices for peach palm reported that an average of only four palms (4.3 for campesino and 1.5 for indigenous populations) were used to provide seed for the establishment of the forest gardens sampled. As expected, inbreeding coefficients observed within communities were relatively high (f = 0.105 − 0.210), however, observed heterozygosities within communities were also high (0.625–0.741). A metapopulation approach was used to describe migration within and among regions, implying a hierarchical structure of gene flow which maintains relatively high levels of genetic diversity. Seed migration was found to occur over longer distances (≤600 km) and at a higher frequency (46% of palms sampled) in the indigenous study area, and a proportionally greater number of alleles was found (49 vs. 43 over three loci) with twice as many private alleles occurring only in the indigenous populations. The farmers’ practice of preserving remnant palms through successive swidden generations may have contributed to the maintenance of alleles by reducing the severity of founder effects. Although the campesino study area exhibited a significant (20% of the variation; p < 0.01) isolation-by-distance relationship across 35 km distance, in general, both study populations had relatively limited genetic structure (θ = 0.012–0.03), which is believed to have resulted from the exchange of seeds over long distances and periods of time.  相似文献   
73.
利用单片段代换系鉴定水稻株高及其构成因素的QTL   总被引:8,自引:0,他引:8  
 通过t测验比较了单片段代换系与受体亲本华粳籼74之间的表型差异,对以6个水稻品种为供体的52个单片段代换系代换片段上株高及其构成因素的QTL进行了鉴定。以P≤0.001为阈值,在14个代换片段上共鉴定出24个QTL,包括10个株高QTL、2个穗长QTL、4个倒1节间长QTL、5个倒2节间长QTL、3个倒3节间长QTL,这些QTL分布于水稻的9条染色体上。QTL加性效应值为-4.08~3.98 cm,加性效应百分率为-19.35%~10.43%。  相似文献   
74.
一个简便的适合于分析油菜中SSR位点的检测体系   总被引:17,自引:5,他引:17  
介绍一个DNA用量少、灵敏度高、重复性好和快速简便的适合于分析油菜中SSR位点的检测体系,该体系对于其它作物的SSR标记分析也有一定的参考价值。  相似文献   
75.
DNA was isolated from seedlings of Quercus robur, collected from a single provenance, and from epicormic, crown shoots and in vitro shoots from a single tree of Q. petraea using a CTAB method of extraction. DNA was obtained in sufficient quantity and purity, from 13 out of 30 seedlings, and from all isolations from epicormic and in vitro shoots (2.5–10.0 μg/g fresh/ weight). Smearing was minimised at a primer concentration of 0.12 μM with Taq polymerase at 0.5 unit/reaction. Nine primers produced 142 bands, 28 of which were polymorphic. A similarity index showed that 11 seedlings were closely related with high coefficients (0.85–0.90), but each could be identified from another using only 9 primers (OPA-02 and -05, OPG-04 and -05, OPE-01, -02, -03, -08, -09). DNA was isolated from crown, epicormic and in vitro leaves originating from a single 150-yr old tree of Q. petraea and analysed by randomly amplified polymorphic DNA (RAPD) and microsatellites. With each primer, a characteristic RAPD pattern was obtained, and it was common to all six epicormic shoots derived from different parts of a single branch of this tree; also to the shoots from the crown of the same tree with OPE1 OPA-05, OPA-08, OPA-01, OPA-02, OPA-04, OPA-05, OPG-02, OPG-10, OPE-12. Similarly, the RAPD pattern obtained from shoot cultures in vitro, derived from individual nodes of epicormic shoots produced by six different branch segments, were uniform for each of 15 primers. This work was repeated using microsatellite PCR. Three microsatellite loci AG16, AG 1/2 and AG 1/5 were amplified by PCR. It showed a uniformity of these microsatellite loci in shoots from the crown of the tree, and from epicormic shoots cultures derived from six different sections of branch.  相似文献   
76.
12 cattle microsatellite DNA markers were used for establishing the paternity of 4 Datong Yak calves.The results indicated that paternity can be assigned by use of exclusion method directely when the mother is clearly known and data of all likely sires were obtained. The more the alleles of a locus possessed, the more effectively the paternity can be assigned. Not only the microsatellite DNA marker is a promising tool in establishment of yak detail pedigrees, but also can provide us information of reproductive efficiency of the bull(s) based on the numbers of calves it produced in the herd, which will be useful in speeding up the processes of yak genetics improvement.  相似文献   
77.
绵羊毛色遗传机制研究评析   总被引:2,自引:0,他引:2  
陈玉林 《家畜生态》1997,18(4):46-48
绵羊毛色遗传机制的研究既有理论价值又具现实意义。本文就有关绵羊毛色变异及毛色位点的已有研究成果进行了评析,旨在总结该领域的研究情况,借以促进我国绵羊毛色的遗传学研究。  相似文献   
78.
选用健康家兔40只,取仰卧位保定,5%戊巴比妥钠溶液麻醉,对家兔胸部体层摄影技术进行了探讨。几何条件:使用直线轨迹时,曝光角度以20°为好;使用区域圆轨迹时,以12°为好。显示支气管的最佳层次()与胸厚(X)的回归方程(?)=0.739X-1.922。物理条件:kVP=胸厚(cm)+40+10(滤线器);mA及s:直线轨迹时100mA,0.3s;区域圆轨迹时20mA,2.8s。并对所拍摄的X线体层照片进行了分析,在显示胸部某一层面的结构上和对肺脏、支气管部位病变的诊断上,体层摄影有明显的优点,而麻醉对改善体层片的质量有一定作用。  相似文献   
79.
多重聚合酶链反应筛选方法的研究   总被引:6,自引:0,他引:6  
本文提出了筛选多重聚合酶链反应的常用方法,根据该法将56个牛微卫星组成的21个多重聚合酶链反应组合,其中14个三微卫星组合,7个二微卫星组合,这些多重聚合酶链反应组合可用于大批量测定微卫星的试验,如基因定位及亲子鉴定等。  相似文献   
80.
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