SSR分子标记鉴定铁皮石斛与霍山石斛的正反交后代

以铁皮石斛与霍山石斛的正、反交F1代共63株为试验材料,利用SSR标记鉴定杂种真实性。结果表明,在21对石斛基因组引物中,筛选出双亲多态性引物3对,多态性引物占比为14.3%。用此3对引物可鉴定出铁皮石斛×霍山石斛杂交苗中25株真杂种,比例为78.1%,可鉴定出霍山石斛×铁皮石斛杂交苗中28株真杂种,比例为90.3%。     

钢/聚丙烯/钢复合板拉深中钢板变形有限元分析

用弹塑性大变形有限元方法模拟钢／聚丙烯／钢复合层板的拉深成形过程，揭示了两层钢板的塑性应变发展过程，分析了不同变形区域的塑性变形特征。对内层钢板，从板料中心沿径向依次处于非塑性变形状态、径向伸长类变形、周向压缩类变形状态。而对外层钢板，从板料中心沿径向则依次处于非塑性变形状态、周向压缩类变形状态、径向伸长类变形状态、周向压缩类变形状态。     

地市级农科所以科技创新推动地方产业发展的实践与思考 ——以江苏里下河地区农业科学研究所为例

文章以江苏里下河地区农业科学研究所为例,总结了其以科技创新推动地方产业发展的实践经验,分析了地市级农科所以科技创新推动地方产业发展存在的问题,如农业科技创新投入强度偏低、科研成果与市场脱节、农业科研与科技推广不能有效衔接等,并从加大对基层科研单位的科研投入力度、发挥市场和政府等多元化主体作用、优化农技推广服务体系、转变传统科技创新思路等方面提出了有针对性的建议,以期推动科技创新与产业发展深度融合。     

日粮中使用低纤维饲料对奶牛消化情况影响的研究

【目的】研究在日粮中使用10 kg饲用甜菜替代3 kg玉米青贮、在日粮中使用1/3开花期和现蕾期苜蓿干草对奶牛消化情况的影响。【方法】试验采用单因素设计。根据泌乳天数、胎次、年龄、产奶量相近的原则,选取荷斯坦奶牛51头,随机分为3组,分别饲喂对照组(甜菜粕+玉米青贮+1/3开花期苜蓿干草)、试验1组(饲用甜菜+玉米青贮+1/3开花期苜蓿干草)、试验2组(饲用甜菜+玉米青贮+现蕾期苜蓿干草)3种粗饲料组合的日粮,每组混合精料相同。试验预饲期7 d,正式期43 d。【结果】日粮中使用饲用甜菜和现蕾期苜蓿干草饲喂奶牛可以提高有机物、粗蛋白、粗脂肪和无氮浸出物的消化情况,但差异不显著(P>0.05)。【结论】现蕾期苜蓿干草的品质优于1/3开花期苜蓿干草,饲用甜菜是一种低纤维多汁饲料,日粮中使用饲用甜菜和现蕾期苜蓿干草可以提高奶牛的消化情况。     

中国美利奴羊(新疆型)皮肤组织GAPDH基因实时荧光定量PCR方法的建立

【目的】建立GAPDH内参基因实时荧光定量PCR方法,为进一步研究中国美利奴羊(新疆型)相关基因的定量表达奠定基础。【方法】采用中国美利奴羊(新疆型)皮肤组织为试材,根据Genebank中绵羊GAPDH基因序列,设计并合成一对引物,建立基于SYBR Green I染料技术的Real-Time PCR检测体系,绘制出标准曲线并对其熔解曲线分析。【结果】以cDNA为模板建立的标准曲线循环阈值(Ct)与标准cDNA模板在一定浓度范围内呈良好的线性关系,GAPDH基因标准曲线中模板拷贝数(X)与Ct值的关系为Ct=一3.679 51g/X+35.648,相关系数R=0.999 8;试验重复性好,批内和批间变异系数(CV%)分别为0.22%～3.45%和1.30%～4.89%。【结论】所建立的方法具有快速、线性范围广、重复性强等特点,GAPDH可作为内参基因用于绵羊相关基因的定量表达研究。     

饲用玉米生物产量和籽粒产量与相关因素的灰色关联分析

运用灰色关联分析方法对13个饲用玉米品种生物学产量和籽粒产量与相关因素关系的研究分析,结果表明,饲用玉米生物学产量与主要性状间的关联度顺序为:株高>穗位高>成熟期保绿度>穗行数>行粒数>结实长>吐丝期>穗长>穗粗>籽粒产量>千粒重;籽粒产量与主要性状间的关联度顺序为:千粒重>穗长>结实长>行粒数>穗粗>行数>生物产量>株高>穗位高>成熟期保绿度>吐丝期。     

饲用型玉米陕单8806高产栽培密度研究

通过对饲用型玉米陕单8806进行37500、48000、58500和69000株/hm2等4个密度试验,结果表明:陕单8806的适宜栽培密度为63000株/hm2左右,其吐丝期的合理叶面积指数为5.8左右,该密度下陕单8806拔节至成熟的物质净同化率可达14.3g/(d·m2)左右。     

利用隶属函数法综合评价冬小麦的抗旱性

选取9个抗旱性不同的冬小麦材料，在水旱两种条件下测定了各最佳测定时期的脯氨酸含量、丙二醛含量、叶片相对含水量、切叶失水率、叶绿素含量及a/b比值等抗旱生理指标。利用隶属函数法对材料进行了抗旱性综合评价。     

Effect of cell mediated immunity regulation of duck enhanced by duck IFN-α eukaryon expression plasmid and inoculated with DPV attenuated vaccine by gene-gun

In order to study the effect of cell mediated immunity regulation of duck IFN-α eukaryon expression plasmid (pcDNA-SDIFN-α) on duck plague virus (DPV) attenuated vaccine in ducks, pcDNA-SDIFN-α was administered to 28-day-old ducks at doses of 1, 3 and 6 μg per duck, respectively, by gene-gun. PBS and empty vector pcDNA were used as control. Fifteen days later, all ducks were injected with DPV attenuated vaccine and blood samples were collected at 3, 7, 14, 21, 28, 35, 49, 63 and 84 days after injection. T-lymphocyte proliferation tests (MTT) were used to detect the T-lymphocyte proliferation in the peripheral blood (PBL) of ducks. Blood samples collected at 7, 14, 21, 28, 35 and 49 days after injection were detected by fluorescence-activated cell sorter (FACS) for recording the number of CD₃ ⁺ T-lymphocytes of ducks. Results were as follows: (1) Reaction of T-lymphocytes in PBL to ConA (OD value) of ducks treated with pcDNA-SDIFN-α was higher than that of PBS and pcDNA control groups in 3–84 days. There were highly significant differences between the 1 μg per duck group and the two control groups in 3–84 days (P ⩽ (0.01), between the 3 μg per duck group and the two control groups in 3–84 days (P ⩽ 0.01, P ⩽ 0.05), and between the 6 μg per duck group and the two control groups in 7–49 days (P ⩽ 0.01, P ⩽ 0.05). The significant difference was also present between the groups of 1, 3 and 6 μg per duck in 3–35 days (P ⩽ 0.05). However, there was no significant difference between the 3 and 6 μg per duck groups (P ⩾ 0.05). The pcDNA control group was higher than PBS control group, but no difference was detected (P ⩾ 0.05). (2) Change of the number of CD₃ ⁺ T-lymphocytes in ducks administered with different doses of pcDNA-SDIFN-α was higher than that of PBS and pcDNA control groups in 7–49 days. The change in the 1 μg per duck group was significantly higher than that in PBS and pcDNA control groups in 14–49 days (P ⩽ 0.01). There were significant differences between the 3 μg per duck group and the two control groups in 21–49 days (P ⩽ 0.01, P ⩽ 0.05) and between the 6 μg per duck group and the two control groups in 7–49 days (P ⩽ 0.01, P ⩽ 0.05). However, no significant differences among the groups of 1, 3, and 6 μg per duck groups (P ⩾ 0.05) and between the two control groups (P ⩾ 0.05) were found. The results indicated that pcDNA-SDIFN-α administered 15 days before injection of DPV-attenuated vaccine could significantly enhance cellular immunity induced by DPV-attenuated vaccine. pcDNA-SDIFN-α is an excellent DPV-attenuated vaccine molecular adjuvant and the best result can be obtained with the dose of 1 μg per duck of pcDNA-SDIFN-α inoculated by gene-gun. __________ Translated from Acta Veterinaria et Zootechnica Sinica, 2007, 38 (10): 1066–1071 [译自: 畜牧兽医学报]     

Review of the Methods for Developing SSR Molecular Markers

Microsatellite marker （or Simple Sequence Repeate, SSR） is a marker technology based on DNA molecular length poly morphism. It is also one of the most commonly used molecular markers. Traditional SSR marker development methods are relatively time-consuming and mostly relying on the known genome sequence information while recently developed methods of SSR marker based on RAPD, ISSR-PCR SSR, the use of hybrid options, sequence tag SSR library access and screening EST-SSR have been widely used. This paper gave an overview of the methods mentioned above for the development of SSR markers.