Cryosurvival and pregnancy rates: One‐step protocol for freezing–thawing Shangri‐la Yak (Bos grunniens) Embryos

The yak is one of the most important and economically useful animals for highlanders. The decline in the yak population requires effective measures for the conservation and multiplication of elite germplasm. A standardized protocol will simplify the freezing and warming of yak embryos in straw and facilitate embryo transfer. In this work, we investigated a one‐step protocol that uses a stable basal medium, which comprised a warming medium (1.08 M sucrose) and a freezing medium (EFS40). We also assessed the effects of the new transfer method on embryo survival. A total of 145 yak frozen embryos were thawed in a standard medium system. The one‐step protocol led to a high recovery percentage (84.93) of yak embryos that survived vitrification and warming. The in vitro survival rates of these embryos significantly different from those of embryos frozen–thawed via the conventional method. The 95 embryos frozen–thawed via our one‐step protocol were then implanted in selected recipients. Thirty‐six singleton pregnancies were established. In conclusion, the proposed one‐step method is a simple, safe, and standardized freezing–thawing protocol that ensures embryo survival and quality under field conditions. This study establishes new possibilities for the widespread use of embryo transfer in yaks.     

Vitrification for bovine embryos with low‐quality grade

This study was conducted to examine the utility of vitrification for bovine embryos with low‐quality grade, and simple cryoprotectants dilution method for practitioners. In Experiment 1, survival of frozen embryos was compared with that of vitrified embryos using minimum volume cooling (MVC). Then, vitrified embryos were used to confirm the optimum sucrose concentration in Experiment 2. The survival rates of embryos that had been vitrified following diluted cryoprotectants with the one‐step in‐straw method were compared with those of fresh control embryos in Experiment 3. Frozen‐thawed or vitrified‐warmed blastocysts were cultured with TCM‐199 supplemented with 100 μmol/L beta‐mercaptoethanol +5% fetal bovine serum at 38.5°C in an atmosphere of 5% CO₂ in air, their survival after 24 hr were compared. The development to term of fair quality in vivo embryos after vitrification was examined in Experiment 4. Results show that survival rates of frozen‐thawed embryos were lower (p < .05) than that of vitrified‐warmed ones. When vitrified embryos were warmed in 0.3 mol/L sucrose in straws, their survival rate was 100%. The total cell numbers of vitrified‐warmed embryos were comparable to those of fresh control embryos. The six calves from 13 vitrified embryos were delivered in Experiment 4. These results indicate that MVC vitrification following one‐step cryoprotectants dilution is utilized to preserve low‐quality bovine embryos.     

基于"三网合一"的基层农户信息服务软件的研制

本软件综合运用各种最新的信息技术以及主动武网关技术,将无线通讯网、固定电话网和互联网络连接在一起,实现信息的无缝跨接,拓宽了互联网络上应用系统的服务范围.农业专家或农技推广员利用本软件可以更加方便、快捷地为基层农户提供信息服务,有效的解决了基层农户信息传递的"最后一公里问题".     

鄂温克旗“两行一带”造林模式分析

鄂温克旗在20世纪90年代初根据当地的实际情况开始摸索带状造林经验,以改变在草原牧区进行集中连片造林的不合理模式。退耕还林工程实施以来,两行一带作为一种新的造林模式在全区推广。鄂温克旗林业技术人员经过示范推广应用,获得了初步成效。通过分析对比,认为两行一带造林模式具有实际应用价值,可望在营林生产中继续推广应用。     

基于林地“一张图”的小班自动编号探究

以林地一张图小班排序编号为研究对象,基于ArcGIS10.2浮动版,用简单的Python语句求算小班周界横坐标最小值、纵坐标最大值,在查找相同的工具制作表中,图层与表连接,在横坐标最小值与纵坐标最大值相等的相邻小班顺序值字段中输入从左到右顺序值用于排序,导出图层属性表,采用Excel 2010函数countif自动编号,图层与Excel表连接,用VBScript语言字符串函数left表达式格式化小班号,对横坐标最小值与纵坐标最大值相等出现错误的小班编号,手动修改小班号错误。其操作简单,容易理解,实用,可解决极少数小班号编号不准确的问题,使小班自动编号准确,符合林业调查规划小班编号规则。     

“一事一议”财政政策实施成效及问题分析

总结分析了福建省大田县农村“一事一议”财政奖补工作的成效和存在的问题,提出加大政策宣传力度、健全组织领导、优化配置奖补资金、加强部门协作、强化监督管理等措施.     

利用酵母单杂交筛选拟南芥AtSTK基因表达调控蛋白的研究

拟南芥丝氨酸/苏氨酸蛋白激酶基因AtSTK的过量表达可以明显提高拟南芥的耐盐性。为进一步研究AtSTK基因表达的调控机制,以拟南芥基因组DNA为模板设计引物,扩增获得AtSTK基因的启动子序列,并构建到报告载体pAbAi,将重组报告载体质粒pAbAi-HYT利用BstbⅠ进行单酶切线性化,转化酵母菌株Y1H Gold,线性化的pAbAi-HYT整合到基因组中。然后,将纯化的拟南芥双链cDNA、pGADT7-Rec载体共转化含有报告载体pAbAi-HYT的酵母菌,将菌液涂布到含有100 ng/m L Ab A的SD/-Leu培养基上进行阳性克隆的酵母单杂交筛选。通过回复鉴定、序列测定,最终筛选获得了可能参与AtSTK基因表达调控的4个拟南芥基因。测序结果表明,酵母单杂交筛选获得的拟南芥基因AT3G32090含有WRKY转录因子保守结构域,为WRKY类转录因子的一员。因此,AtSTK基因的表达很可能接受MAPK信号传导途径中AT3G32090基因编码的WRKY类转录因子的调控,从而影响拟南芥植株的耐盐性。     

The role of sensitivity to abscisic acid and gibberellin in pre-maturity α-amylase formation in wheat grains

To study the role of abscisic acid (ABA) and gibberellin (GA) sensitivity in regulating pre-maturity α-amylase (PMA) in wheat grains, plants were grown in a glasshouse under cold-shock and ambient conditions. α-amylase activity in response to applied ABA and GA was measured in detached-grains with the embryo removed (in vitro) and in intact-grains attached to the plant (in situ). The in vitro experiment was conducted using Spark (low PMA-susceptible genotype) and Rialto (highly PMA-susceptible genotype), with the aim of defining the time point for GA-sensitivity. The results showed an increase in GA-sensitivity at about 640 degree days after anthesis (DAA) in Rialto. There was no evidence for a change in ABA-sensitivity in either variety. The in situ experiments were conducted using genotypes from a Spark × Rialto doubled haploid population segregating for the Rht-D1a (tall) or Rht-D1b allele and for the presence or absence of 1BS/1RS. For Rht-D1a (tall) or Rht-D1b genotypes with or without 1BS/1RS, the cold-shock significantly increased GA-sensitivity, whereas there was no significant change in ABA-sensitivity. These results show PMA is related to an increase in GA-sensitivity that occurs in the aleurone at around 640 degree DAA, and can be enhanced by environmental factors (e.g. cold-shock).     

林业政务信息化发展与研究

阐明了我国电子政务建设的发展特点,就林业政务信息化的架构建设及存在的问题进行了论述。建设我国政务信息化的核心工作、依托基础是建设以“三网一库”为基本架构的全国政府系统办公自动化网络,林业政务信息化建设围绕国家“三网一库”建设的要求,搭建了技术先进、运行稳定、功能相对齐全的网络平台,建设了国家林业局门户网站、办公业务网、办公业务资源网和各类管理信息系统及专业数据库。文章最后根据国家信息化建设的总体要求,结合林业信息化发展现状和行业管理工作的需要,提出了林业政务信息化“十一五”工作的核心内容。