Studies on the Nucleic Acid and Protein Content in the Cotyledon Cells of Lotus Using Fluorescent Imaging System with a Scientific grade Charge Coupled Device

Enzyme dissociated cotyledon cells were obtained from red lotus ( Nelumbo sp. ) on the 5th day and 20th day after fertilization respectively. DNA, RNA and total protein content of individual 5 d and 20 d cell were measured correlatively by microfiuorescent imaging system with a cooled scientific-grade Charge coupled deviced (CCD) camera. The results showed that DNA content of the 20 day cell has become polyploidized from 4C to 8C approximately. The window analysis indicated that relative content of RNA and total protein of the 20 day cell was more than 11 times that of the 5 day cell in the same 4C DNA window respectively. The multiple in-creased of RNA and total protein content was about the same as that of DNA in 2 DNA windows (4C and 8C) of the 20 day cell. These data showed that the enormous accumulation of storage proteins in the cotyledon cells of red lotus depends on both DNA ploidy and selective expression of the subunit genes of the storage proteins during the developmental process.     

Genetic diversity of endangered brown bear (Ursus arctos) populations at the crossroads of Europe, Asia and Africa

Aim  Middle East brown bears ( Ursus arctos syriacus Hemprich and Ehrenberg, 1828) are presently on the edge of extinction. However, little is known of their genetic diversity. This study investigates that question as well as that of Middle East brown bear relationships to surrounding populations of the species.
Location  Middle East region of south-western Asia.
Methods  We performed DNA analyses on 27 brown bear individuals. Twenty ancient bone samples (Late Pleistocene to 20th century) from natural populations and seven present-day samples obtained from captive individuals were analysed.
Results  Phylogenetic analyses of the mitochondrial sequences obtained from seven ancient specimens identify three distinct maternal clades, all unrelated to one recently described from North Africa. Brown bears from Iran exhibit striking diversity (three individuals, three haplotypes) and form a unique clade that cannot be linked to any extant one. Individuals from Syria belong to the Holarctic clade now observed in Eastern Europe, Turkey, Japan and North America. Specimens from Lebanon surprisingly appear as tightly linked to the clade of brown bears now in Western Europe. Moreover, we show that U. a. syriacus in captivity still harbour haplotypes closely linked to those found in ancient individuals.
Main conclusion  This study brings important new information on the genetic diversity of brown bear populations at the crossroads of Europe, Asia and Africa. It reveals a high level of diversity in Middle East brown bears and extends the historical distribution of the Western European clade to the East. Our analyses also suggest the value of a specific breeding programme for captive populations.     

Historical presence of the sturgeon Acipenser sturio in the Rhône basin determined by the analysis of ancient DNA cytochrome b sequences

Sturgeon disappeared from the Rhône River in the mid 70’s without certitude about which species it was and about the existence of a sympatry between European sturgeon, Acipenser sturio, and Adriatic sturgeon, A. naccarii, in this watershed. In order to reach a reliable specific determination of this extinct sturgeon population, archaeozoological remains of the Jardin d’Hiver in Arles city, on the Rhône river banks, were genetically analysed, following strict criteria of authentication for the ancient DNA work. The rich collection of Arles sturgeon bone remains stems from human activities between the 6th and the 2nd Century BC. Sequences of 86 bp of the cytochrome b gene were obtained on four bones, from different anatomical parts of the fish and from different archaeological layers. All gave A. sturio diagnostic sequences. This preliminary analysis is an essential first step in the project of sturgeon reintroduction in the Rhône River. Thus, further analyses on a larger sample are necessary to comfort this result and to solve the question of sympatry with A. naccarii.     

Photosystem Development in Dark-grown Lotus (Nelumbo nucifera) Seedlings (in English)

It is well known that no chlorophyll synthesis and photosystem biogenesis have been detected in dark-grown angiosperm seedlings. However, in this report, we showed that both PSⅡ and PSⅠ could be formed in dark-grown lotus ( Nelumbo nucifera Gaertn.) seedlings. Lots of evidence were given: First, during the dark-grown period, the single fluorescence emission peak at 679 nm in lotus embryo red-shifted and transformed into the normal PSⅡ fluorescence emission; Simultaneously, PSⅠ fluorescence emission at 730 nm appeared and increased obviously; Second, with partial denaturing SDS-PAGE method, PSⅠ chlorophyll-protein complex could be clearly separated from 10 days dark-grown lotus seedlings; Third, the existence of Lhca1 was also proved by Western blots. Moreover, measurements of electron transfer rate demonstrated that both PSⅡand PSⅠ core in dark-grown lotus seedlings were photochemically active.     

土家族源流的遗传学初探

通过分析湖北恩施、湖南吉首地区土家族两个人群样本,利用14个Y染色体非重组区(NRY)单倍群分型技术对土家族的遗传结构进行了研究。分型结果结合其他地区土家族两个人群和相关民族群体进行主成分分析,并将分析结果根据不同人群的地理分布展示在地图上。然后对各主成分和单倍群进行偏相关分析来探讨它们之间的相关性。结果显示土家族主体与汉族在父系结构上比较接近,但依然有一定的区别。同时还发现龙山地区唯一保留土家语的土家族与氐羌族群有很明显的相关性,这说明土家族最早的起源可能正是氐羌民族。实验结果表明,恩施和吉首地区的大部分土家族与周边民族群体间的血缘交流频繁;而龙山和永顺的土家族更能代表土家先民的遗传结构,他们与西部氐羌族群密切相关。     

子莲杂交优势的利用及新品种选育的研究

1981—1987年的试验证实,利用杂交优势是子莲新品种选育的重要途径。作者通过杂交选育和引种,筛选培育出13号(白花建莲×红千叶)和2号(百叶莲×红花建莲)杂交子莲,杂交优势明显而稳定,其产鼠比对照品种——红花建莲增加20%以上,经济效益十分显著。为了推广这两种杂交子莲,作者还提出了子莲良种繁育时防杂的技术措施。     

Local versus landscape-scale effects of anthropogenic land-use on forest species richness

The study investigated the effects of human-induced landscape patterns on species richness in forests. For 80 plots of fixed size, we measured human disturbance (categorized as urban/industrial and agricultural land areas), at ‘local’ and ‘landscape’ scale (500 m and 2500 m radius from each plot, respectively), the distance from the forest edge, and the size and shape of the woody patch. By using GLM, we analyzed the effects of disturbance and patch-based measures on both total species richness and the richness of a group of specialist species (i.e. the ‘ancient forest species’), representing more specific forest features. Patterns of local species richness were sensitive to the structure and composition of the surrounding landscape. Among the landscape components taken into account, urban/industrial land areas turned out as the most threatening factor for both total species richness and the richness of the ancient forest species. However, the best models evidenced a different intensity of the response to the same disturbance category as well as a different pool of significant variables for the two groups of species. The use of groups of species, such as the ancient forest species pool, that are functionally related and have similar ecological requirements, may represent an effective solution for monitoring forest dynamics under the effects of external factors. The approach of relating local assessment of species richness, and in particular of the ancient forest species pool, to land-use patterns may play an important role for the science-policy interface by supporting and strengthening conservation and regional planning decision making.     

碗莲新品种选育研究

本文阐述了作者1982—1987年选育碗莲新品种的试验方法和研究结果。通过实生苗选种和杂交育种,1982—1983年获得碗莲F_1代种子,分别在次年将其直接栽植于钵、碗中,从中选育出12个花型新颖、花色艳丽、适宜家庭种植的优良碗莲新品种。几年的试验证明:实生种苗具有方法简便,有利于发展推广的特点。