牛类胰岛素生长因子结合蛋白3基因PCR-SSCP分析   总被引：2，自引：0，他引：2  

高雪  徐秀容  许尚忠  任红艳  张英汉 《农业生物技术学报》2006,14(4):474-477

采用PCR-SSCP技术分析了牛类胰岛素生长因子结合蛋白3(IGFBP3)基因在南阳牛、鲁西牛和中国西门塔尔牛3个牛品种中的遗传多态性。结果表明:IGFBP3的第3外显子不存在遗传多态性;第2外显子在3个牛品种中检测到了AA、AB和BB基因型,而且A等位基因为3个牛群体的优势等位基因,分布较高。3个品种中,中国西门塔尔牛AA基因型频率最高,达到0.6615,而鲁西牛和南阳牛则相对较低,分别为0.4043和0.3095。对第2外显子的多态片段测序分析表明:位于IGFBP3基因第8069bp处发生单碱基突变T→C,并导致了苯丙氨酸变为亮氨酸。  相似文献   

利用SSR标记分析柑橘雄性不育及低育资源的遗传多样性     

曹庆芹  孟海军  文晓鹏  伊华林  邓秀新 《农业生物技术学报》2006,14(6):937-941

采用SSR标记分析了43份柑橘(Citrus)不育、低育、含不育胞质及13份可育材料的遗传多样性。结果表明,8对SSR引物扩增得到35个等位基因,平均每个位点有4.4个等位基因。利用NTSYSpc2.10统计分析软件,UPGMA法聚类分析表明,56份柑橘资源可分为3组。宽皮柑橘类品种为第一组,甜橙、葡萄柚、椪柑及杂柑类品种为第二组,包含不育胞质的澳洲指橘为第三组。SSR聚类分析还表明本地广橘与温州蜜柑有着紧密的亲缘关系,而与早橘、槾橘、本地早等的亲缘关系较远?涕?不育与低育资源的遗传多样性分析将为此类资源的收集保存及应用提供依据。  相似文献   

The diversity and sustainable development of crop genetic resources in the Lancang River Valley   总被引：3，自引：0，他引：3  

Zeng Yawen  Wang Jianjun  Yang Zongyi  Shen Shiquan  Wu Lihua  Chen Xiaoyan  Meng Jingui 《Genetic Resources and Crop Evolution》2001,48(3):297-306

This paper reviews the status of crop genetic resources in Yunnan province of China from 1978 to 1999. Results are presented of same research in the field of the diversity of cultivated and wild crop. Yunnan is one of the centre of origin or genetic diversity of more than 200 cultivated and wild crops. There are over 500 cultivated plants which account for over 80% of the total in China and more than 650 species of wild crops. In addition, there are more than 440 species of main wild flowers. According to our recently researches there are abundant species, subspecies and varieties of crop genetic resources in Yunnan Province. The Lancang River Valley is the richest genetic diversity centre of rice, maize, wheat, barley, buckwheat, legumes, ramie, sugarcane, vegetable, tea, actinidia and so on. For example, there are 59 varieties (including all varieties of Oryza sativa L. in China) in 5933 accession of Yunnan indigenous rice. The Lancang River Valley is one of the centre for genetic diversity of rice resources and a rich region for elite and rare rice resources of Yunnan, too. In order to protect the highly endangered crop genetic resources in the Lancang River Valley, it is necessary and very important to set up a collection, conservation, utilization and research system, enhancing their protection and utilization, in situ- and ex situ-conservation, farm management and sustainable production.  相似文献   

森林生态系统中初级生产者-分解者养分的关系          下载免费PDF全文

刘增文  潘开文  李雅素 《中国水土保持科学》2003,1(4):102-105

 森林生态系统中,初级生产者和分解者之间的养分关系,是一种既互利又竞争的复杂关系。通过构建初级生产者-分解者系统的养分流动模型,分析分解者增长受碳限制或受养分限制的判断标准。在假定整个系统封闭的前提下,讨论初级生产者与分解者实现共存并保持长久稳定的条件:一是分解者必须受碳限制,这要求分解者较之初级生产者对养分吸收具有更强的竞争力;二是矿化系数与碎屑化系数之比(a41/a23)要足够大于在初级生产者中的碳/养分与在分解者中的碳/养分之比(α/β)。这表明,从化学计量论的角度来看,生态系统的持续和稳定,对碳/养分之比和植物与微生物的竞争能力方面有严格的要求。  相似文献   

Sampling variation in genetic resources of seed crops: a review     

Enrico Porceddu  Ardeshir B. Damania 《Genetic Resources and Crop Evolution》1992,39(1):39-49

Summary The first explorations for the collection of genetic resources of crop plants took place in areas designated as centers of origin. Later, important characters were found to be present in areas other than those indicated by Vavilov. Hence collection missions were extended to cover other areas in addition to the centers of diversity with different ecogeography and agromorphological features. Collecting activities were aimed not only at providing germplasm for immediate use in breeding but also at conserving genetic variation for future contingencies. The analysis of the collected material has revealed the complex nature, amount and distribution of genetic variation present in natural populations as well as in landraces, old varieties and primitive forms. The study of variation for characters from different regions indicated that it is possible to select certain characters for detecting variability in the populations and establishing the minimum number of genotypes to be sampled. A minimum number of 20–130 plants per sample, depending on the crop, is recommended in order to capture 95% of the total variation in the field. However, it has been emphasized that the number of different populations sampled rather than the sample size per population determines the overall efficiency of a collection. The findings reported allow better utilization of the collected material and formulation of optimal and cost-effective sampling strategies for the future.  相似文献   

应用RAPD技术研究4种鲍的亲缘关系   总被引：8，自引：2，他引：8  

黎中宝 《中国生态农业学报》2004,12(4):60-63

应用RAPD技术研究 4种鲍的亲缘关系结果表明 ,4种鲍群体中 2 0个有效引物共扩增出 5 38条DNA带 ,平均每个引物扩增的条带数为 2 6 .9;扩增的多态性条带数 136 ,平均每个引物扩增的多态性条带数为 6 .8;多态位点百分数为 2 5 .3%。盘鲍群体和皱纹盘鲍群体之间遗传距离与遗传一致度分别为 0 .2 8和 0 .72 ,杂色鲍群体和九孔鲍群体之间遗传距离与遗传一致度分别为 0 .32和 0 .6 8。聚类分析把盘鲍群体和皱纹盘鲍群体聚为 1组 ,二者亲缘关系较近 ;杂色鲍群体和九孔鲍群体聚为 1组 ,二者亲缘关系也较近  相似文献   

流域侵蚀产沙物理成因模型评述     

赵海镜  严军  薛海  王鹏涛 《中国水土保持》2004,(11):21-23

回顾了国内外流域侵蚀产沙模型的发展过程 ,对各类产流产沙模型的特点进行了比较。介绍了物理成因模型的概念及当前研究工作中存在的问题  相似文献   

用传感器阵列和遗传基因块区分两种食醋     

邹小波  赵杰文  吴守一 《农业工程学报》2002,18(5):226-230

近年来,对将传感器阵列技术和模式识别技术用于识别食品挥发气味的研究方兴未艾。模式识别技术的实施主要依赖于对传感器阵列输出信号的参数表达,迄今为止,不论是单个传感器还是传感器阵列均没有通用的参数选择的方法。该文从8个氧化锡气敏传感器与食醋气味反应中提出初始特征值,采用一种基于公式表达树的遗传基因块代码的编码算法的组织特征参数法(OFP)对所提取的特征参数进行融合,从而得到最优的组织特征参数很容易区分不同的气味。它不但解决了怎样得到最优特征参数的问题,而且用这种算法进行遗传运算更直观、更方便。并详细讨论了怎样进行基因编码来融合不同特征参数,同时对这种遗传算法怎样进行选择、交叉、变异进行了研究。将其用于气敏传感器阵列对不同食醋识别的应用实例证明,该方法是一种非常有效的模式识别方法  相似文献   

Completion of the agronomic evaluations of Medicago ruthenica [(L.) Ledebour] germplasm collected in Inner Mongolia   总被引：3，自引：0，他引：3  

T. A. Campbell  G. Bao  Z. L. Xia 《Genetic Resources and Crop Evolution》1999,46(5):477-484

Because Medicago ruthenica [(L.) Ledebour] is a potential new forage legume, we collected 90 accessions in Inner Mongolia in 1991. The 40 accessions evaluated in this study (E2) trace to 13 collection sites ranging from 40° 40 (N) × 111° 15 (E) to 42° 55 (N) × 122° 20 (E) and to altitudes ranging from 175 to 1493 m. Nineteen of these accessions were collected from new or under-represented sites in generally milder and drier climates (temperate desert steppes), compared to the 50 accessions evaluated earlier (E1). All accessions were evaluated at Beltsville, MD (USA) on a B and K deficient Iuka sandy loam (coarse-loamy, siliceous, acid, thermic, Aquic Udigluvent; pH 6.4) in two-year studies. Significant variation was noted in E1 and E2 for dry matter yield, growth habit, leaf shape, and plant height and width. Upright growth habit and leaf narrowness, and procumbency and yield were positively correlated in both evaluations, but no particular leaf shape or growth habit was correlated with tolerance to winter conditions. In E2, leaf:stem ratios of four M. ruthenica accessions and a cultivated alfalfa (M. sativa L.) check were not significantly different, but M. ruthenica was significantly more tolerant of potato leafhopper (Empoasca fabae Harris) feeding than was M. sativa. Second-year alfalfa dry matter yield was about five times larger than that of M. ruthenica. Many of the highest yielding accessions were collected near cultivated fields and/or buildings. Although data for both evaluations demonstrated the same basic trends, there were sufficient deviations to emphasize the value of evaluating the entire germplasm collection.  相似文献   

Diversity for abiotic and biotic stress resistance in the wild annual Cicer species     

K.B. Singh  B. Ocampo  L.D. Robertson 《Genetic Resources and Crop Evolution》1998,45(1):9-17

Data on 228 accessions of eight annual wild Cicer species and 20 cultivated chickpea check lines were evaluated for diversity in response to six of the most serious biotic and abiotic stresses which reduce crop yield and production stability of chickpea, i.e., ascochyta blight, fusarium wilt, leaf miner, bruchid, cyst nematode, and cold. Relative frequencies of score reactions to the above six stresses were recorded from all the annual wild Cicer species and the cultivated taxon. Patterns of distribution and amount of variation of the resistance reactions differed between stresses and species. C. bijugum, C. pinnatifidum and C. echinospermum showed accessions with at least one source of resistance (1 to 4 score reactions) to each stress. Overall, C. bijugum showed the highest frequencies of the highest categories of resistance. Next in performance was C. pinnatifidum followed by C. judaicum, C. reticulatum and C. echinospermum. Furthermore, C. bijugum had the highest number of accessions with multiple resistance to the six stresses; two accessions were resistant to five stresses and 16 to four. According to the Shannon-Weaver diversity indices (H), five species showed discrete mean diversity indices which varied from 0.649 in C. pinnatifidum to 0.526 in C. judaicum, whereas C. chorassanicum, C. cuneatum and C. yamashitae showed the lowest Hs, which were respectively 0.119, 0.174 and 0.216. Pair-wise correlations among the six biotic and abiotic stresses showed the possibility of combining these resistances. Interestingly, multiple resistant accessions were predominantly of Turkish origin.  相似文献