Identification and pathogenicity of Cryphonectriaceae species associated with chestnut canker in China

Cryphonectriaceae species cause serious canker diseases on chestnut, oak and eucalypt trees. Recently, canker symptoms with typical orange fruiting bodies were observed on Chinese chestnut and oak trees in Hebei, Hubei, Shaanxi and Shandong Provinces in China. In the present study, isolates of these fungi were identified based on phylogenetic and morphological evidence, and their pathogenicities were tested on detached chestnut (Castanea mollissima) branches. DNA sequence comparisons of the internal transcribed spacer (ITS) regions and two regions of β-tubulin (TUB1/TUB2) indicate that these isolates represent five species in the Cryphonectriaceae, viz. Cryphonectria japonica, Cryphonectria parasitica, Aurantiosacculus castaneae sp. nov., Cryphonectria neoparasitica sp. nov. and Endothia chinensis sp. nov. The sexual morph of Aurantiosacculus is discovered for the first time and can be distinguished from the other genera in Cryphonectriaceae by dark brown ascospores and tubiform appendages at both ends. Cryphonectria neoparasitica sp. nov. is different from the other Cryphonectria species by its aseptate ascospores. Endothia chinensis sp. nov. is the sole species in Endothia infecting the host genus Castanea. Additionally, it is much smaller than E. gyrosa and narrower than E. singularis in ascospores. The inoculation results showed that these five Cryphonectriaceae fungi isolated from chestnut or oak are all pathogenic to tested chestnut branches. Cryphonectria parasitica appears to be the most aggressive fungus, followed by C. neoparasitica sp. nov., C. japonica, E. chinensis sp. nov. and A. castaneae sp. nov.     

关于公鱼属鱼类分类的讨论

本文回顾了公鱼属鱼类的分类历史,讨论了分类存在的问题,提出了赞同把该属分成形态特征和生态习性明显不同的两个种的意见:淡水产卵的定为池沼公鱼(H.olidus(Pallas),海水产卵的定为海公鱼(H.pretiosus(Girard)。     

数值分类法在玉米品种资源上的应用

本文应用主成分分析法对湖北省201份玉米品种资源的28个性状进行分析,结果表明,前7个主成分对变异的累计贡献率达79.5%,以前7个主成分为综合指标进行系统聚类,在遗传距离D²=1.50水平上聚成7大类;不同类群间的性状具有明显差异,而类群内特征相似;其中Ⅲ、Ⅴ、Ⅵ类为综合性状较好的种质类群。     

隆头鱼科分类学研究进展

隆头鱼科是体形最为分化、体色最为多变的一个类群,其所包含的种类数位居海洋鱼类第2位。尽管经历了260多年的分类研究,隆头鱼科在分类单元和物种鉴定方面仍存在许多争论和疑问。回顾了隆头鱼科分类学发展史,总结了系统发育学的研究成果,描述了隆头鱼科关键分类特征和基础生物学,概述了几个分类较为复杂的主要属的研究进展,根据分子系统发育,推测几个主要属为复系群,是颌骨摄食功能进化导致种间显著遗传分化的结果。同时,参考1750—2017年期间的文献资料,考证和修订了中国隆头鱼的同物异名和错误命名,厘定中国隆头鱼科有38属150种,并提出我国需要广泛深入的开展隆头鱼科物种的普查和鉴定研究工作及利用分子生物学技术开展隆头鱼亲缘地理学的研究建议,为隆头鱼的起源、物种多样性、分布格局成因以及在海洋生态系统中的功能研究提供基础数据及理论研究参考。     

四川省土壤温度状况空间分布特征

土壤温度状况(STR)在现代土壤系统分类中是确定土壤分类单元的重要诊断特性。利用四川省160个气象站点的多年年均和月均地面气候资料与数字高程模型数据,分析不同气象因子与地形因素对土壤温度(土温)的影响,然后以显著影响的因子为辅助变量,采用回归克里格法预测四川省STR的空间分布,依据中国土壤系统分类高级与基层分类划分标准中有关STR的定量诊断指标,对四川省STR及其空间分布特征进行分析。结果表明,气温、经度、纬度与海拔对土温有显著影响,在高级分类划分标准下,四川省STR以热性、温性、寒性为主,部分区域为永冻、冷性、高热;在基层分类划分标准下,四川省STR以热性、温性、冷性为主,部分地区为高寒性、近寒性、亚寒性、高热性。四川省STR分析为四川土壤系统分类与土壤资源的合理利用提供了科学依据。     

武夷山土壤形成特点与系统分类

选取武夷山土壤垂直带中 6个代表性剖面 ,研究了土壤的形成条件和特点 ;按照《中国土壤系统分类 (修订方案 )》 ,鉴定了诊断层和诊断特性 ,检索了土壤系统分类名称 ;随海拔由低到高 ,依次为湿润富铁土—湿润淋溶土—常湿淋溶土—常湿雏形土等亚纲 ;并与发生学分类、美国土壤系统分类 (USST)以及世界土壤资源参比基础 (WRB)等不同分类系统中的土壤类别归属作了参比     

Classification of Azolla spp., section Azolla

Summary Azolla accessions (section Azolla) from the germplasm collections of the International Rice Research Institute and Washington State University were fingerprinted and classified by enzyme electrophoresis and leaf trichome morphology. A. filiculoides was enzymatically distinctive and also reliably identified by its prominent one-celled trichomes. Neotropical accessions labelled as A. filiculoides proved to be members of other species. Two groups of isolates were designated A. rubra, but those from Japan were identified as A. filiculoides. The A. rubra of Australia-New Zealand was biochemically unique and possessed less protuberant trichomes than A. filiculoides. A. microphylla, A. mexicana, and A. caroliniana were phenetically similar, but a. microphylla was identifiable from the others in the banding patterns of certain enzymes. A. mexicana and A. caroliniana were closely related enzymatically. The two-celled leaf trichomes of these three species were similar in size and shape.     

辣椒地方品种的主成分分析及数量分类

为了进一步优化辣椒杂交品种，估算了36个辣椒地方品种的主要病害抗性、果实营养含量和农艺性状等15个性状的主成分值，并将其分为5大类．结果表明：数量分类的结果基本反映了辣椒品种间的遗传差异，符合实际情况．当主成分的特征值的累计贡献率大于75％时，主成分值就能基本反映原来性状的遗传特征．比较不同的系统聚类方法，类平均法较好地适用于辣椒品种的数量分类。     

中国栅蚤蝇分类研究（双翅目：蚤蝇科）

本文首次系统地记述了中国栅蚤蝇种类与分布，描述栅蚤蝇６种，其中１新种，３中国新记录种，编制了中国种类的分类检索表，提供了鉴别特征图。模式标本存于沈阳农业大学植物保护系标本室。     

中国条眼管蚜蝇属种类记述

本义对条眼管蚜蝇属ＥｒｉｓｔａｔｏｄｅｓＭｉｋ．１８９７的分类、属征进行了慨述，并记录了中国分布的２种，其小１种：带状条眼管蚜蝇Ｅｒｉｓｔａｌｏｌｅｓｔａｅｎｉｏｐｓ（Ｗｉｅｄｅｍａｎｎ，１８１８）为中国首次记录，在文中首次对该种的雄性外生殖器进行了描述并绘制了特征图。给出了２种的检索表和分布范围。