Isozyme analysis of genetic diversity in wild Sicilian populations of Brassica sect. Brassica in view of genetic resources management

In Sicily and in the small surrounding islands the section Brassica of the genus Brassica comprises five species, B. insularis Moris, B. incana Ten., B. macrocarpa Guss., B. rupestris Raf. and B. villosa Biv. These taxa represent a genetic resource as relatives of kale crops but some populations are endangered or threatened, thus isozyme analyses were performed to assess the genetic diversity degree at population and species levels in order to assist the design of conservation management programs.Eleven loci from five enzyme systems (aconitase, leucine aminopeptidase, 6-phosphogluconate dehydrogenase, phosphoglucoisomerase phosphoglucomutase) were analyzed in sixteen natural population (fifteen from Sicily, one from Calabria). Mean within-population genetic diversity was moderate (P = 41%, A = 1.54, H = 0.16). In some cases a great number of heterozygous individuals were detected, in other cases fixation index (F) deviated significantly from Hardy-Weinberg genotypic expectations.A total of 37 alleles was recognized, six of which resulted exclusive to single populations. The among-population component of the total genetic diversity (Gst mean values) for each species was 0.30–0.37, indicating genetic differentiation among populations.Among B. villosa and B. rupestris populations genetic distance values resulted rather low and they resulted high with B. incana and B. macrocarpa populations.The results are discussed with regard to the distribution of the genetic diversity level and the genetic resources management.     

Decomposition in five woodland soils: relationships with some invertebrate populations and with weather

Summary In two alluvial forests, a beech forest, an oakhazel-wood and a spruce forest, correlations between abiotic factors and the different groups of soil animals on the one hand and the decomposition rate (mean rate of disappearance) on the other hand have been the subject of investigation. There is a positive correlation between Lumbricidae and Brachycera imagines and the pH and the decomposition rate, but a negative one with Enchytraeidae and Nematocera imagines.Varying weather conditions are of great importance for decomposition processes. The influence of temperature seems to be insignificant. In the deciduous forests fluctuations of precipitation correlate fairly well with fluctuations in rates of decomposition, because of the high abundance of lumbricids. The spruce forest has very few lumbricids and the influence of weather on the course of decomposition is insignificant. Yet there is only a very loose relationship with the annual fluctuations of weather conditions. Only a major event such as the relatively low temperature and precipitation of 1980 is capable of inhibiting the development of sciarid larvae and enchytraeids and hence reducing the ensuing decomposition rate in 1981 and possibly even in 1982. The reason for this is that sciarid larvae and imagines, for example, go through critical periods during their development, which are influenced by the weather, frequently with a time lag of 1 year.Long-term investigations in the spruce forest have established a high correlation between sciarid larvae and enchytraeids and the decomposition rate.Dedicated to the late Prof.Dr. M.S. Ghilarov     

Clinical disorders observed in anteaters (Myrmecophagidae,Edentata) in captivity

The major health problems found in 103 captive lesser anteaters (Tamandua tetradactyla) and giant anteaters (Myrmecophaga tridactyla), family Myrmecophagidae, are presented and correlated with management. The most common of 200 recorded clinical disorders involved the digestive system (26%), nutritional deficiency (20%), injury (15.5%), respiratory system (10%), skin (7%) and circulatory system (4.5%), but 13% of the cases were inconclusive. Parasites were identified in 48.5% of faecal samples, mainly the eggs of nematodes (40%), of which the commonest wereTrichuris spp (28%) andStrongyloides spp (11%); protozoa (16%), of which the commonest wereEimeria spp (10%),Entamoeba spp (5%) andGiardia spp (1%); and cestodes (8%) and acanthocephalids (1%). Bacteria cultured from the various materials includedSalmonella enteritidis, S. cholerasuis, Escherichia coli, Enterobacter aerogenes, Streptococcus spp andStaphylococcus spp. The ectoparasites found wereAmblyomma spp andOtodectis spp (Arthropoda, Acaridae).     

青蛤不同地理群体遗传结构差异的AFLP分析

[目的]探讨青蛤种群遗传多样性水平和遗传分化特征。[方法]采用AFLP技术对我国山东潍坊(WF)、江苏南通(NT)、浙江宁波(NB)、浙江温州(WZ)沿海共4个青蛤地理群体的遗传结构差异进行了分析。[结果]5对引物共得到261个位点,4个群体的多态位点比例平均为82.95%,其中WZ群体最高(86.97%),NT群体最低(78.93%);4个群体Nei’s基因多样性指数分别为0.258 1、0.252 6、0.271 3和0.277 6,香农多样性指数分别为0.394 7、0.383 0、0.412 0和0.421 4;群体遗传变异主要来自于群体内,占96.39%;WF和NT群体、NB和WZ群体遗传关系较近,聚类分析分别先聚在一起。[结论]研究的青蛤4个群体遗传基础较好,且尚未有明显的遗传分化。     

基于SSR标记的山西省辽东栎自然居群遗传多样性分析

利用SSR分子标记对山西省8个辽东栎天然群体进行遗传多样性分析,并与北京东灵山小龙门林场群体进行地理距离和遗传距离相关关系的对比分析,旨在为辽东栎遗传多样性保护提供一定的依据。研究使用11对SSR引物进行遗传多样性分析,得到平均等位基因数为10.272 7,平均有效等位基因数为5.185 9;得出山西省辽东栎群体的平均期望杂合度为0.753 8,Nei多样性指数为0.752 1,Shannon多样性指数为1.754 3。这一结果表明辽东栎的遗传多样性水平是相对较高的。研究还表明,辽东栎群体的绝大部分遗传变异是发生在群体内的（95.99%）,仅有4.01%的遗传变异发生在群体间,并且遗传距离和地理距离之间具有显著的正相关关系（r=0.752 2,P0.05）。      

陕西黄河湿地鸟类资源调查分析与研究

陕西黄河湿地是我国中、西部国际候鸟的主要栖息地之一和内陆候鸟迁徙通道上的重要驿站,区内生境多样,鸟类资源十分丰富。通过对湿地内高生芦苇区、低矮芦苇区、盐碱地、农田、鱼塘、莲池、滩涂、林地等不同生境类型的鸟类分布情况进行的调查分析,结果共记录到16目39科132种,较2005年增加了3科13种,为陕西黄河湿地鸟类资源保护提供了科学依据。     

Behavioural response of a trophic specialist, the Iberian lynx, to supplementary food: Patterns of food use and implications for conservation

Prey scarcity compromises population survival, especially for specialist predators. Supplementary feeding is a management tool that can be applied to reverse the decline of food-limited populations. We analyse how a population of Iberian lynx, a threatened food specialist, initially reacted to, and subsequently used, supplementary food. Twenty-seven feeding stations (FS) with domestic rabbits were placed in the Doñana Biological Reserve, SW Spain, between 2002 and 2005. We recorded lynx tracks inside and around stations to analyse spatio-temporal patterns of use, as well as the performance of several station designs. Iberian lynx used 62% of the FS installed, and consumed most of the supplied food. All station designs were used and food provision apparently covered the energetic needs of the lynx inhabiting the reserve. There was spatial aggregation in the use of the FS. Fourteen weeks were needed on average for lynx to become familiar with feeding stations and making a regular use of the supplementary food. Seasonal variations in consumption frequency appeared to be modulated by fluctuations of wild rabbit numbers throughout its annual cycle as well as by variation in energy demand of breeding females. The Iberian lynx responded positively to our supplementary feeding programme. We show that this technique allows the persistence of lynx populations during long periods in areas where wild rabbits are extremely scarce. Supplementary food may be used to sustain lynx whenever rabbit populations need recovery, as well as in the context of lynx restocking or reintroduction programmes.     

Temperature Before Cold Acclimation Affects Cold Tolerance and Photoacclimation in Timothy (Phleum pratense L.), Perennial Ryegrass (Lolium perenne L.) and Red Clover (Trifolium pratense L.)

The expected temperature rise in late summer/early autumn can change the conditions for acclimation and affect the winter survival of perennial crops. This study examined the effect of the temperature just before the onset of cold acclimation (pre‐acclimation) on freezing tolerance of timothy (Phleum pratense L.), perennial ryegrass (Lolium perenne L.) and red clover (Trifolium pratense L.) populations (both cultivars and breeding populations) adapted to either northern or southern parts of Norway. Using phytotron experiments, we studied whether increasing pre‐acclimation temperature delays growth cessation, affects photoacclimation and reduces freezing tolerance. Furthermore, we assessed whether these effects were related to the latitudinal adaptation of the plant material. The results showed that a rise in pre‐acclimation temperature decreased both cold acclimation capacity and photoacclimation in these species. This affected the freezing tolerance, which was reduced significantly more in northern‐adapted population of timothy and perennial ryegrass compared with southern‐adapted populations. Red clover was less affected by temperature changes than the grasses.