Molecular mapping for seedling cold tolerance QTLs in rice

The quantitative trait loci(QTLs)for cold tolerance relative characters were identified with microsatellite markers.Ten QTLs located on chromosome1,3,4,5,6,8,9,11(two)and 12were detected for seedling height at different low temperature.Only 2 of these were detected at the same locus at four environments.1 was significant at three environments.6 were significant at two environments and 1 was significant at one environment.Seven QTLs located on chromosome 1(two),2(two),5,6,8were found for ow temperature chlorosis resistance and five QTLs located on chromosome 3,4,7,8,11resistant to chilling injury.The amount of variation explained by indivdual QTL ranged from 4.85%to 49.34%,There was no linkage relationship among the three characters.which indicates seediling cold tolerance is a complex character and is controlled by different QTLs.     

Action research on alternative land tenure arrangements in Wenchi,Ghana: learning from ambiguous social dynamics and self-organized institutional innovation

This study reports on action research efforts that were aimed at developing institutional arrangements beneficial for soil fertility improvement. Three stages of action research are described and analyzed. We initially began by bringing stakeholders together in a platform to engage in a collaborative design of new arrangements. However, this effort was stymied mainly because conditions conducive for learning and negotiation were lacking. We then proceeded to support experimentation with alternative arrangements initiated by individual landowners and migrant farmers. The implementation of these arrangements too ran into difficulties due to intra-family dynamics and ambiguities regarding land tenure. Further investigations to find out how ambiguities could be tackled revealed that the local actors themselves had taken initiatives towards developing institutional innovations to reduce ambiguities. However, there is still considerable scope for further development of these self-organized innovations. The article ends with a reflection on inter-disciplinary action research, where it is argued that making “mistakes” is an inherent and necessary characteristic in action research that aims to address complex social issues.

中国东方蜜蜂的形态学及生物地理学研究

 用形态学研究方法对中国的东方蜜蜂(Apis cerana)的形态特征进行研究。东方蜜蜂的标本从中国大陆的34个样点采集而来，这些样点代表了东方蜜蜂在中国大陆不同气候带或地理区域分布的不同类型。 34个点共采集了220群蜜蜂的样，每群蜂测定分析15只工蜂，形态的测定特征参照Ruttner 1988年提出的测定标准进行。每只蜂总共有38个测定的形态特征。测定的性状特征的数据进行因素分析，集合分析和区辨分析；形态性状与生态环境因子相关性分析；并与周边国家东方蜜蜂的相关数据进行比较，发现:生活在吉林长白山温带阔叶林的东方蜜蜂个体较大、体色较黑，与日本、韩国的东方蜜蜂较为相似；来自亚热带常绿阔叶林的东方蜜蜂（甘肃天水、湖北和湖南）与云南北部、北京、尼泊尔的东方蜜蜂聚集为一类；而居住在南方热带季雨林如：福建、广东、广西和云南部分南方的东方蜜蜂与低海拔亚热带常绿阔叶林的东方蜜蜂（越南、中国四川和安徽黄山）聚集为另一类； 云南南方如：景洪、思茅、河口、镇康、元江、屏边、蒙自草坝和开远的东方蜜蜂形成独特的一个分枝，与泰国和缅甸的东方蜜蜂非常接近，同时与亚热带常绿阔叶林的东方蜜蜂相邻；值得关注的是，来自高寒湿地的东方蜜蜂（甘肃岷县）是目前在亚洲已经发现的东方蜜蜂中，其个体最大、颜色最深。在因素分析和集合分析里，它具有独特的位置。     

太行山羊遗传检测

应用随机整群抽样方法，对太行山羊的两个群体共72只成年羊，用淀粉凝胶电泳法测定了33个血液蛋白座位，并对毛色和外形特征进行了检测。结果表明，运铁蛋白（Tf）、前白蛋白－3（Pa－3）、肽酶－B（Pep-B）、碱性磷酸酶（Alp）、亮氨酸胺肽酶（LAP）和酯酶－D（Es-D)6个血液蛋白座位表现多态性，多态位点比例为0．1818；12个类别 25种外型特征中7个有变异体；4个毛色座位有变异。平均杂合度分析表明，太行山羊变异程度较大（H＝0．555），说明太行山羊群体有效规模较大，目前尚未面临急 待保种的局面.     

PCR技术在蜜蜂疾病诊断中的应用*

 由于蜜蜂疾病的传统诊断方法费时、费力,因此开发快速诊断技术非常重要。分子生物学技术的发展为其提供了可能。笔者对PCR技术在蜜蜂疾病诊断中的应用现状作了综述,并对其中存在的问题和应用前景进行了探讨。     

Carbonate deposition, climate stability, and Neoproterozoic ice ages

The evolutionary success of planktic calcifiers during the Phanerozoic stabilized the climate system by introducing a new mechanism that acts to buffer ocean carbonate-ion concentration: the saturation-dependent preservation of carbonate in sea-floor sediments. Before this, buffering was primarily accomplished by adjustment of shallow-water carbonate deposition to balance oceanic inputs from weathering on land. Neoproterozoic ice ages of near-global extent and multimillion-year duration and the formation of distinctive sedimentary (cap) carbonates can thus be understood in terms of the greater sensitivity of the Precambrian carbon cycle to the loss of shallow-water environments and CO2-climate feedback on ice-sheet growth.