大棚作物-水稻种植模式对稻谷产量和氮素面源污染的影响

通过田间试验,分析了常规施肥的麦茬稻与不施肥的大棚作物茬稻的产量、田面水氮素含量的差异和不同施氮肥期对大棚作物茬水稻的产量效应.结果表明:在水稻生育前期,常规施肥的麦茬稻田田面水总氮量为不施肥的大棚作物茬的6.02倍,水稻增产10.64%;前茬为大棚作物时,水稻全季不施基肥、仅在叶龄余数4或5时一次追肥(施氮量75 kg/hm2)可比不施肥增产23%以上,此氮素管理模式有使大棚作物茬水稻增产和降低氮素面源污染的正向作用.     

“胰岛素-转铁蛋白-硒钠”对山羊卵母细胞体外成熟及胚胎发育的影响(英文)

[Objective] The research aimed to enhance culture efficiencies of oocyte and embryo of goat in vitro and to explore serum-free culture system in vitro.[Method] At present,the conventional solutions of oocyte maturation and embryo development in vitro were always added into 1% ITS(Insulin-transferrin-selenium) or using 1% ITS to replace FBS in 2 kinds culture solutions for conducting in vitro cultures of goat oocyte and parthenogenetic embryo.The influences of ITS on their developments were detected.[Result] ITS in maturation liquid of oocytes could not increase oocytes maturation rate but significantly increased blastocyst rate (58.06% vs. 48.19%)of parthenogenetic embryo.If FBS in maturation liquid of oocytes was replaced by ITS, the maturation rate, cleavage rate and blastocyst rate were basically unchanged.Adding ITS into embryo medium could increase blastocyst rate (68.30% vs. 56.82%)of parthenogenetic embryo of goat.If FBS in embryo medium was replaced by ITS,the cleavage rate didn’t change basically,while the blastocyst rate in ITS was obviously lower than that in FBS group(42.33% vs.56.82%).[Conclusion] ITS could promote maturation of oocyte in vitro and early embryonic development, in addition,ITS could replace serum in maturation medium of oocyte as serum-free culture system for conducting relevant researches.     

体细胞核移植法获得转人乳铁蛋白基因克隆山羊妊娠的研究(英文)

[Objective] The aim of this study is to understand the effects of donor cell type,embryo stage,number and transfer position on the efficiency of goat transgenic clone.[Method] Using somatic cell nuclear transfer technology,the single goat fetal fibroblasts(GFF)and mammary gland epithelial cells(GMGE)harboring human lactoferrin(hLF)gene were transferred to the enucleated oocyte.Reconstructed karyoplast-cytoplast couplets were fused,activated,and cultured in vitro.Embryos at 2-8 cell stage were transferred into oviduct of synchronized recipients,and blastocysts were transferred into uterine horn.[Result] The pregnancy rate was similar between GFF and GMGE(oviduct transfer:26.47% vs.20.00%),and between oviduct transfer and uterine horn transfer(26.47% vs.25.00%)for GFF group;pregnancy rate in the group with the mean number of embryo transferred per recipient of 21.2 was significantly higher than in those the 5.93 group and 9.64 group(40.00% vs.26.67% and 21.43%).[Conclusion] These results indicate that pregnancy rate of goat transgenic clone couldn’t be affected by donor cell type,embryo stage and transfer position but be done by the number of embryo transferred per recipient.In addition,the study also suggests the feasibility of making transgenic goat using GMGE as donor cells.     

小麦免耕高产栽培技术

旱地春小麦是克什克腾旗的主要粮食作物之一,常年播种面积在30万亩左右,占本地播种面积的22%,大都分布在旱地高原漫甸近年来,由于市场化进程的加快,粮食价格的回升,农民种植积极性提高,克什克腾旗小麦种植面积开始回升,仅次于玉米,在农业增效、农民增收中起着重要作用。为了提高小麦单产,节约成本,减轻劳动强度及规范种植技术,克什克腾旗引进了小麦免耕栽培技术。     

冬枣开甲技术及配套管理措施

文章从冬枣开甲适宜的树龄、树势、时间、温度、湿度、开甲的方法及甲口保护等方面介绍了冬枣开甲技术,并从开甲前、开甲期、开甲后3个时段介绍了与开甲相对应的配套管理措施,以期为生产者提供参考,提高冬枣坐果率,达到优质、丰产、稳产的目的。     

遮阳网覆盖对夏白菜产量和硝酸盐含量的影响

夏白菜生产使用遮阳网对产量和品质有较大影响,对决定安全品质的硝酸盐的影响更要引起重视.夏白菜生产宜选用黑色、遮光率较高的遮阳网.本试验选用遮光率为75%的黑色遮阳网,3种处理方法、4个处理水平,以不使用遮阳网为对照,经过对植株形态、产量以及硝酸盐含量的比较得出:遮阳网浮面覆盖测定前6 d揭掉的处理最理想,其次为遮阳网浮面覆盖测定前4 d揭掉的处理.     

人溶菌酶基因cDNA的克隆和序列分析

根据GenBank中的人溶菌酶(hLYZ)mRNA序列设计引物,以人胎盘组织总RNA为模板,通过RT-PCR方法扩增出长度为0.85 kb的hLYZ cDNA序列,经过序列测定表明所克隆的片段与已发表的hLYZ cDNA序列的同源性为99%。推导的氨基酸序列经blastp分析与人溶菌酶蛋白质前体的同源性为97%,成熟肽的同源性为99%,为进一步构建人溶菌酶基因乳腺特异性表达载体奠定了基础。     

我国农机市场的历史演变及其特征

农机市场是农机工业和农业机械化发展的重要影响因素。文中系统地分析了农机市场的形成和发展，对阶段的划分、对每个阶段的市场特征作了归纳和总结，把市场发展的一般性与农机市场发展的特殊性统一起来。对全面认识、完善农机市场，促进农机市场健康发育，保证农业生产、农机工业的发展等有借鉴意义。     

山羊卵母细胞的显微受精及胚胎培养

采用胞质内精子注射（ICSI）构建山羊显微受精胚，在两种培养液（CR1aa和SOFaa）与颗粒细胞共培养条件下，分别添加不同浓度的牛卵泡液（BFF）和胎牛血清（FBS），研究其对山羊卵母细胞显微受精胚体外发育的影响。结果表明：①在CR1aa培养液与颗粒细胞共培养条件下，添加10％BFF的ICSI胚的囊胚发育率最高（22．2％），显著高于添加5％（13．1％）和15％（2．7％）组。②在SOFaa培养液与颗粒细胞共培养条件下，添加10％BFF的ICSI胚的囊胚发育率（25．1％）显著高于添加5％（12．9％）和15％（3．0％）组。③在两种培养液中，分别添加10％BFF和10％FBS，ICSI胚的囊胚率分别为22．6％和26．9，5．8％和6．1％。表明：CR1aa和SOFaa两种培养液都适宜山羊的1CSI胚体外培养；在早期胚胎培养中，添加10％BFF可显著提高ICSI胚的囊胚发育率：添加10％BFF比添加10％FBS对提高早期胚胎培养质量更为有效。     

电液气门机构在汽车发动机上的初步应用

自主开发了一套电液气门机构并进行了气门试验研究,试验结果表明,该机构能够实现各气门参数的独立可变。在此基础上,将该机构应用于实际发动机,在火花点火(SI)模式下发动机能够正常运行,其性能达到并略优于原气门机构的发动机。通过进气门晚开、排气门早关策略捕捉缸内热残余废气形成内部EGR,实现了汽油可控自燃(CAI)燃烧。