利用RAPD技术对碧桃种质资源的分析

利用RAPD技术,采用从200个随机引物中筛选的22个随机引物对8个碧桃类型的基因组DNA进行扩增,通过扩增的180个位点的谱带的聚类,分析供试碧桃的系统发育,并运用特殊谱带,建立了碧桃的分子检索表,并提出了重点保存的碧桃种质。     

Clay mineralogy,specific surface area and micromorphology of polygenetic soils from Eastern Kansas

The objective of this study was to evaluate the relationship between clay mineralogy, specific surface area (SSA) and micromorphology in polygenetic Konza soil series. Physical, chemical and mineralogical analyses were performed on disturbed soil samples, and micromorphological investigations of selected horizons were done on undisturbed soil samples. X-ray diffraction indicated that lower part of each parent materials has more mectite and less clay mica content than that of the upper horizons in each parent material. Greater amounts of smectite can be attributed to transformation product of the clay mica in to smectite, eluviation from upper horizons or originated from parent material. Specific surface area of upper horizons in each parent material tended to increase to lower horizons. Clay content gradually increased from surface (21%) to the lower part (～48%) of the solum. Clay in Bt horizons had strong birefrengent, sharp boundary, and strong orientation pattern. SSA, clay content increase, clay mineralogy and oriented clay features agreed to one another. Therefore, this relationship gives opportunity to make predictions on extend of SSA and related soil processes by looking at one of these features.     

利用RAPD分子标记研究酵母菌的亲缘关系

采用随机扩增多态性DNA(RAPD)分子标记对6个属的21个酵母菌株的基因组DNA的多态性进行了研究,并采用聚类分析法评价它们之间的亲缘关系.研究表明,RAPD能够检测出酵母种内微小的遗传学差异,以其特征谱带作为酵母菌种鉴定的特征标记.聚类分析结果显示,休哈塔假丝酵母与热带假丝酵母之间亲缘较近,遗传距离为0.114,它们与毕赤树干酵母之间遗传距离为0.493;粟酒裂殖酵母与卡斯伯酒香酵母的亲缘关系较近,遗传距离为0.322;嗜单宁管囊酵母与克鲁斯假丝酵母间的亲缘较近,遗传距离为0.383,它们与酿酒酵母间的遗传距离达到0.443,与产朊丝酵母聚类的遗传距离是0.471.除假丝酵母属外,大多数酵母属、种间的分类结果与经典形态学分类结果相符.