Isolation,Culture and Identification of Testis Sertoli Cells in Mongolian Horses in vitro

To study a simple and rapid separation of testis Sertoli cells in Mongolian horses and ensure their activity,the testis tissue of two-year-old Mongolian horses was mechanically isolated under a low temperature environment in this experiment,and 1-3 g of testis tissue was chopped,the free red blood cells and interstitial cells were removed by gravity precipitation method.0.1% collagenase Ⅳ and 0.25% trypsin-EDTA were used for tissue digestion, and cells were cultured in medium containing 10% fetal bovine serum.After inoculation,the purified Sertoli cells were isolated and purified by differential sticking method,and the impurity cells were removed by Tris-HCl infiltration method,and were identified by alkaline phosphatase (AKP) staining,HE staining and Real-time quantitative PCR.The results showed that most of the cells began to adhere to the wall after culture 24 h,and the shape of the cells was oval.After culture 48 h,the cytoplasm increased and the refraction became stronger.After culture 3-4 d,the cytoplasm of the cells expanded into tight junction.At this time,the cells were triangular with obvious nucleoli.After culture 6-7 d,the cells entered the stable phase.Real-time quantitative PCR results showed that the expression of GATA4 and GDNF genes were extremely significantly expressed in cultured cells (P<0.01).AKP staining supported the negative expression in Sertoli cells,indicating that the isolated cultured cells were indeed Sertoli cells.In this experiment,tissue was treated by mechanical separation and two-step enzyme digestion,and testicular support cells were obtained quickly and efficiently,the method of culturing Sertoli cells in Mongolian horses testis in vitro was successfully constructed.     

PRATIQUE: a research project to enhance pest risk analysis techniques in the European Union

PRATIQUE is an EC-funded 7th Framework research project designed to address the major challenges for pest risk analysis (PRA) in Europe. It has three principal objectives: (a) to assemble the datasets required to construct PRAs valid for the whole of the EU, (b) to conduct multi-disciplinary research that enhances the techniques used in PRA and (c) to provide a decision support scheme for PRA that is efficient and user-friendly. The research will be undertaken by scientists from 13 institutes in the EU and one each from Australia and New Zealand with subcontractors from institutes in China and Russia. They will produce a structured inventory of PRA datasets for the EU and undertake targeted research to improve existing procedures and develop new methods for (a) the assessment of economic, environmental and social impacts, (b) summarising risk while taking account of uncertainty, (c) mapping endangered areas (d) pathway risk analysis and systems approaches and (e) guiding actions during emergencies caused by outbreaks of harmful organisms. The results will be tested and provided as protocols, decision support systems and computer programs with examples of best practice linked to a computerised European and Mediterranean Plant Protection Organization (EPPO) PRA scheme.     

苜蓿蓟马抗性与生理活性相关性研究

1材料与方法1．1试材与试验地概况供试材料为现蕾期的草原2号紫花苜蓿、敖汉苜蓿、阿尔冈金苜蓿及自选抗蓟马新品系紫花苜蓿。试验地设置在呼和浩特内蒙古农业大学科技园区牧草试验站内种植3年的人工草地。该地位于东经111°48’,北纬40°48’,海拔1063m,属于典型大陆性气候,日气温最高和最低分别为36．9℃和-33℃,年均气温5．4℃,≥10℃年积温2915℃,年平均降水量350-400mm,主要集中在7-9月,无霜期135d：     

蓟马对紫花苜蓿危害的空间分布特征

昆虫空间分布格局是其种群的一种客观属性,对于同一种群,其格局类型是固有的.蓟马为一种体型较小的昆虫,取食时移动性强,易逃逸,所以用危害特征的空间分布来代替其本身的空间分布更具有稳定性和实用性.采用不同尺度研究探讨蓟马对紫花苜蓿危害的空间分布特征.研究表明在现蕾期危害空间分布为聚集分布,危害斑块尺度是40 cm×30 cm～50 cm×30 cm的椭圆型,长轴方向是东西向.因此在这一物候期选择抗蓟马材料时,取样应该按南北方向,尺度距离大于40～50 cm,更具有代表性,在开花期危害空间分布为均匀分布,但是取样尺度也应大于40～50 cm,更具有代表性,而且在开花期取样要比现蕾期取样更好一些,会减少取样误差.     

Development of a complete set of disomic rape-radish chromosome-addition lines

After crosses of multiple rape-radish chromosome additions with rape, nine different monosomic additions (2n = 4x = 38 + 1) of individual radish chromosomes, a–i, were isolated, having the genomic background of winter oil seed rape and radish cytoplasm. Extra chromosomes were identified with RAPD markers, specific for individual radish chromosomes. All radish-plasmic monosomic additions, except that of chromosome f, had low seed production due to pistilloid stamens. Rape cytoplasm was substituted by crossing the monosomic additions as pollinators to rape followed by reselection of the radish chromosome additions. The monosomic additions in rape cytoplasm showed normal male fertility. Average transmission rates of radish chromosomes via egg cells and pollen cells were 37% and 27%, respectively. Lowest male transmission was found for chromosomes e and f with 0.04 and 0.01. Monosomic additions were self-pollinated to produce disomic additions. Monosomic and disomic addition progenies were discriminated by a prescreening with quantitative double primer (dp) RAPDs and cytological confirmation of preselected candidates by FISH analysis using a Raphanus-specific probe. Usability of this complete set of nine disomic rape-radish additions (2n = 4x = 38 + 2) was discussed.     

Ancient diets, ecology, and extinction of 5-million-year-Old horses from florida

Six sympatric species of 5-million-year-old (late Hemphillian) horses from Florida existed during a time of major global change and extinction in terrestrial ecosystems. Traditionally, these horses were interpreted to have fed on abrasive grasses because of their high-crowned teeth. However, carbon isotopic and tooth microwear data indicate that these horses were not all C4 grazers but also included mixed feeders and C3 browsers. The late Hemphillian Florida sister species of the modern genus Equus was principally a browser, unlike the grazing diet of modern equids. Late Hemphillian horse extinctions in Florida involved two grazing and one browsing species.     

Development of phytoplankton communities and common off-flavors in a biofloc technology system used for the culture of channel catfish (Ictalurus punctatus)

The use of biofloc technology production systems continues to increase in the aquaculture industry worldwide. Recent research demonstrated that outdoor biofloc systems can be used to produce high yields of channel catfish (Ictalurus punctatus). However, studies have not yet been performed to determine the development and composition of phytoplankton communities and related off-flavor problems in these biofloc production systems. In this study, water samples were collected biweekly from May to November and channel catfish samples were collected during harvest in November from nine 18.6 m² biofloc culture tanks. Water and fillet samples were analyzed for levels of the common off-flavor compounds geosmin and 2-methylisoborneol (MIB). The development and composition of phytoplankton communities in each culture tank was also monitored. In addition, water and biofloc samples were evaluated to assess the microbial sources of geosmin and MIB within the culture tanks. Phytoplankton (including algae and cyanobacteria attached to bioflocs) biomass, as determined by concentrations of chlorophyll a in the water, gradually increased in all tanks over time. Phytoplankton communities that developed in the culture tanks were dominated by fast-growing, unicellular and small colonial types of green algae (chlorophytes) and diatoms (bacillariophytes) and slower growing, small colonial types of cyanobacteria (cyanophytes). A positive correlation (p < 0.05) between cumulative feed addition and chlorophyll a concentration was found. Although geosmin and MIB were present in the culture water of each tank during most of the study, levels were typically low and only one tank yielded catfish with geosmin and MIB in their flesh at levels high enough to be designated as off-flavor. A positive correlation (p < 0.05) between cumulative feed addition and MIB concentrations in the water of culture tanks indicates a greater potential for MIB-related off-flavor problems at high feed application rates. The microbial sources responsible for production of geosmin and MIB in the culture tanks remain unknown.     

Construction of a chromosome-assigned,sequence-tagged linkage map for the radish,Raphanus sativus L. and QTL analysis of morphological traits

The radish displays great morphological variation but the genetic factors underlying this variability are mostly unknown. To identify quantitative trait loci (QTLs) controlling radish morphological traits, we cultivated 94 F₄ and F₅ recombinant inbred lines derived from a cross between the rat-tail radish and the Japanese radish cultivar ‘Harufuku’ inbred lines. Eight morphological traits (ovule and seed numbers per silique, plant shape, pubescence and root formation) were measured for investigation. We constructed a map composed of 322 markers with a total length of 673.6 cM. The linkage groups were assigned to the radish chromosomes using disomic rape-radish chromosome-addition lines. On the map, eight and 10 QTLs were identified in 2008 and 2009, respectively. The chromosome-linkage group correspondence, the sequence-specific markers and the QTLs detected here will provide useful information for further genetic studies and for selection during radish breeding programs.     

蒙古马睾丸支持细胞的体外分离培养与鉴定

为研究一种简单快速分离蒙古马睾丸支持细胞并保证其活性的基本方法,本试验采集2岁蒙古马睾丸组织于低温环境下进行机械分离,将1~3 g睾丸组织剪碎,采用重力沉淀法去除游离的红细胞和间质细胞;使用0.1%胶原酶Ⅳ和0.25%胰蛋白酶+EDTA逐步进行组织消化,并用含有10%胎牛血清的培养基进行细胞培养;在接种后采用差异贴壁法分离纯化支持细胞,使用Tris-HCl低渗法去除杂质细胞,并采用碱性磷酸酶（AKP）染色、HE染色、实时荧光定量PCR方法进行鉴定。结果显示,支持细胞贴壁性能较强,培养24 h后大多数细胞开始贴壁,细胞形状呈椭圆形;培养48 h后胞质增多,折光性变强;培养3~4 d细胞胞质展开紧密连接,此时细胞呈三角形,有明显的核仁,培养6~7 d细胞生长状态进入稳定期。实时荧光定量PCR结果显示,GATA4和GDNF基因在培养细胞中极显著表达（P<0.01）,AKP染色支持细胞呈阴性表达,表明分离培养的细胞确为支持细胞。本试验使用机械分离法与两步酶消化法处理组织,可快速高效地获得睾丸支持细胞,成功构建了蒙古马睾丸支持细胞体外培养方法。     

Earthworms promote the reduction of Fusarium biomass and deoxynivalenol content in wheat straw under field conditions

A field experiment was conducted to elucidate ecosystem services provided by earthworms on the repression of phytopathogenic and toxinogenic fungi. The study focussed on decomposing Fusarium culmorum-infected and deoxynivalenol (DON)-contaminated wheat straw remaining on the soil surface as part in conservation tillage. Mesocosms were established in the topsoil of a winter wheat field located in Northern Germany, where conservation tillage has been practised for 20 years. Besides a non-earthworm treatment, two earthworm species were inoculated in the mesocosms either separately or combined: Lumbricus terrestris (anecic, detritivorous) and Aporrectodea caliginosa (endogeic, geophagous). The earthworms were exposed either to artificially Fusarium-infected wheat straw highly contaminated with DON or to non-infected straw serving as a control. The experiment was conducted during an eight week period after harvest from mid August to mid October. For both species, the artificially Fusarium-infected and DON-contaminated wheat straw was a more attractive food source than the non-infected control. In contrast to A. caliginosa, L. terrestris incorporated infected straw faster into the soil compared to control straw. Furthermore, the reduction of Fusarium biomass and DON concentration in wheat straw was significantly higher in the presence of L. terrestris than in treatments with A. caliginosa and without earthworms. Here, no significant differences could be measured between the Fusarium biomass and DON concentration in wheat straw. A. caliginosa seems not to be relevant for the reduction of Fusarium biomass and DON concentration. We concluded that amongst earthworms, anecic detritivorous species are the drivers to compensate possible negative consequences (like crop infection) of conservation tillage. They take an important role in the control of phytopathogenic and toxinogenic fungi surviving on plant residues and in the degradation of their mycotoxins.