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991.
A. Omrani-Sabbaghi M. Shahriari M. Falahati-Anbaran S.A. Mohammadi A. Nankali M. Mardi B. Ghareyazie 《Scientia Horticulturae》2007
To study the genetic variation in Iranian olive collections and some foreign olive cultivars, 47 accessions of 18 local cultivars from 6 olive collections of Iran (Roudbar, Zanjan, Ahvaz, Dezful, Kazeroon and Shiraz), were analyzed along with 30 imported cultivars using 16 microsatellite primer pairs. All the used microsatellite loci revealed polymorphism in the studied genotypes, except GAPU14 and GAPU113 markers. Fourteen microsatellite primers amplified 126 polymorphic alleles in the 87 selected olive accessions. The average number of alleles per locus was 9, ranging from 3 to 14. Polymorphic information content (PIC) was 0.85. The genetic similarity based on Jaccard coefficient ranged from 0.15 to 1. The genetic relationships among accessions were investigated using cluster analysis and principal component analysis (PCA). Most of the accessions with the same name were grouped together; some exceptions were also observed. As expected, close relationship was observed among accessions within same cultivar. Most of the Iranian olive accessions were clustered to a main distinct group. Two-dimensional scatter plot of principal component analysis revealed a clear separation of most of the Iranian olives from Syrian and other introduced cultivars. These suggest that Iranian cultivars have different origin related to West Mediterranean basin cultivars and have evolved independently from the others. Between and within Iranian and foreign cultivars (cultivars including three or more accessions) genetic diversity was analyzed using analysis of molecular variance (AMOVA). AMOVA revealed higher within cultivar genetic variation (62.76%) as compare to that between cultivar variations (37.24%). The intra- and inter-cultivar variance tested by permutation test showed significant genetic variation at both levels. The high level within cultivar genetic variance could be due to mislabeling and presence of homonyms in cultivars produced by vegetative propagation from original plants. 相似文献
992.
扁穗牛鞭草种质遗传多样性的ISSR分析 总被引:2,自引:10,他引:2
用ISSR标记对来自中国西南地区(四川、重庆、贵州)的28份扁穗牛鞭草材料的遗传多样性进行了检测。从96个ISSR引物中共筛选出13个多态性明显、反应稳定的引物。28份材料的DNA共扩增出129条谱带,平均每个引物扩增出9.9条带,多态性条带比率达84.2%。材料间遗传相似系数为0.466~0.980,表现出丰富的遗传多样性。通过聚类分析和主成分分析,将28份扁穗牛鞭草分为两大类,同一地区的扁穗牛鞭草品种(系)基本聚在同一类,呈现出一定的地域性分布规律。 相似文献
993.
胚胎遗传操作是现代生物技术研究最为活跃的领域之一。本文简要介绍了动物胚胎工厂化生产及胚有细胞基因导入所取得的进展;并展望了该项技术在畜牧生产中的应用前景。 相似文献
994.
“中苜一号”紫花苜蓿耐盐遗传特性初步研究 总被引:5,自引:1,他引:4
以“中苜号”紫花苜蓿耐盐新品种为材料,应用NCⅡ杂交试验方案,研究其耐盐遗传参数,旨在为今后苜蓿耐盐育种提供理论依据。结果表明,在直 迫下,苜蓿的干重、株高和分枝数诸性状的加性产应大于显性效应,狭义跗力较大,分别为0.425、0.387和0.484,具有通过选择进一步提高耐盐性的遗传潜力。 相似文献
995.
天山马鹿清原品系产茸量遗传标记的研究 总被引:4,自引:3,他引:1
本文是把天山马鹿清原品系的部分生物信使指标作为产茸的标记性状进行了研究。结果表明,清原品系马鹿血浆8项生物信使指标在各锯别间具有一定波动,T3、T4、cAMP、AKPs活力与鲜茸重呈显著正相关(r=0.8669、r=0.835、r=0.8349、r=0.9801),AKP同工酶快型个体的平均产茸量均高于慢型个体;该试验还建立了预测产茸量的线性多元回归方程。 相似文献
996.
本从NOVELL网常规管理、建立多重配置的无盘工作站、网络的安全运行措施三个方面探讨NOVELL教学网络的科学管理。 相似文献
997.
刘子菁 《吉林农业科技学院学报》2013,(3):65-66,111
语言是社会成员之间相互交际、思维的工具,网络语言则是近些年来伴随着网络的迅速发展而新兴的一种有别于传统平面媒介的语言形式,语用偏离是一种言语表达手段,语用偏离具有超越于字面意义、文学审美和情感美的功能,语用偏离对网络新生语言具有重要的影响. 相似文献
998.
本研究针对迄今有关小麦小分子RNA(miRNA)家族成员介导植株氮素吸收和利用机理尚少见报道的现状,对TaMIR1129的表达特征和介导植株抵御低氮逆境功能进行了研究。结果表明,TaMIR1129呈低氮胁迫诱导表达,表现为随氮浓度降低(0.02~6mmol/L)和处理时间延长(0~48h)表达水平不断增高特征。此外,低氮诱导的高表达水平在恢复供氮后表达下调。表明该miRNA对介质中氮素应答呈典型的时间及浓度依赖特征。TaMIR1129作用2个靶基因,包括Molybdenum cofactor sulfurase(TaMCS)和Major facilitator family transporter(TaMFFT),上述基因应答低氮特征与TaMIR1129相反。遗传转化结果表明,超表达TaMIR1129具有显著增强植株抵御低氮逆境的能力。表现为与野生型对照相比,转基因系Sen 1和Sen 2低氮处理后植株形态增大,干质量增加,氮累积量增多。表明TaMIR1129与作用靶基因构建miRNA/target模块在介导植株抵御低氮逆境中发挥重要作用。 相似文献
999.
Public participation is crucial for sustainable forest management. In particular, in urban forest areas, it is an important tool for overcoming conflicts among diverse needs regarding the forests through collaboration between citizens and governments. Such collaboration requires social learning. Social learning is dependent upon the presence of social networks that serve as an infrastructure for social capital. This study analyses the role of the social network in a participatory forest management approach of the Nopporo Forest Regeneration Project (NFRP) in the urban Nopporo National Forest in Hokkaido, northern Japan, aimed at restoring a typhoon damaged forest.Within the framework of the participatory approach the project hascreated a network of several citizen organizations for exchanging information. Outside this formal NFRP network several additional citizenorganizations are concerned about the Nopporo Forest management. The article describes the overall social network that has evolved around the Nopporo Forest and compares the attitudes and evaluations of the NFRP network organizations and the not formally NFRP related organizations towards their collaboration with government agencies and other citizen organizations. The overall social network around the Nopporo Forest had a multi-nodal character with the National Forest Agency and Hokkaido Prefectural Government acting as main central nodes. Only a few citizen organizations had direct relations to both central nodes; many organizations had links to either the National Forest Agency or the Prefectural Government. The organizations involved in the formal NFRP network had close ties with the National Forest Agency. This contributed to a positive evaluation of present forest management approach and the collaborative activities of the government agencies. In contrast, the organizations that were not involved in the formal NFRP network were found to have fewer ties with the National Forest Agency. The lack of opportunity to form a direct social learning relation hindered the formation of social capital and resulted in a lower evaluation of the participatory management approach as well as of the collaborative activities. Thus, although the participatory forest management approach of establishing formal social networks enhanced collaboration between the National Forest Agency and several citizen organizations and social learning, it was less successful in encouraging a democratic process involving all interested citizen organizations. 相似文献
1000.
教学与教务管理工作是高校教育工作的一项重要内容,其中,教务信息对教务管理工作有相当的重要性。目前,网络传播已成为教务信息传播的主要方式之一。通过分析教务信息网络传播的现状,指出其传播特点。从传播媒介、传播者和传播环境3个方面提出了教务信息网络传播面临的一系列问题和对策,并且探讨了教务信息网络传播对于教学教务管理工作的重要意义。 相似文献