家蚕黑尾病及其防治方法研究

家蚕黑尾病主要是由曲霉菌在蚕尾部寄生引起的一种真菌病 ,从病蚕中分离到病原菌有两种 ,一种孢子表面棘多而长、黄褐色 ,孢子大 ,直径 4～ 6 μm ;一种孢子表面棘短而少、蓝绿色 ,孢子小 ,直径 2～ 3μm。黑尾病在高温多湿条件下多发 ,多发生于 4龄中期至 5龄中期。黑尾病病原菌侵染寄生家蚕的过程是 :病原菌分生孢子附着在蚕尾部背板与节间的三角形节间膜处 ,分生孢子发芽侵入蚕体产生黑色小病斑 ,随病情加重病斑加大 ,甚至在病斑处出现节间断裂 ,直至形成黑尾症状。使用药剂防治黑尾病以 5 %亚迪蚕保最佳     

Heterosis, direct and maternal genetic effects on semen quality traits of rabbits

A complete diallel cross involving two rabbit sire lines (C and R) was carried out to estimate the crossbreeding genetic parameters of seminal traits. 2140 ejaculates from 153 males were analyzed. The traits studied were: presence of gel plugs (G), urine (U), and calcium carbonate deposits (CC), number of useful ejaculates (UE), pH, volume (V), mass and individual motility (Mm, Mi), useful Mi (UM), concentration (Cn), number of spermatozoa per ejaculate (TSE), percentage of viable spermatozoa (Vi), spermatozoa with normal apical ridge (NAR), normal spermatozoa (Nr), spermatozoa with morphological abnormalities of head (H), neck-midpiece (Nm), and tail (T), presence of proximal and distal cytoplasmic droplet (Dp, Dd).

Estimates of heterosis, direct and maternal genetic effects were obtained from the solutions of the mixed model. There were major differences in direct genetic effects between lines, which were favourable to line C for Cn and TSE, and unfavourable for CC, Nm and Dp. Smaller differences were also observed in Vi and NAR favourable to line R. Differences between lines with respect to the maternal genetic effects were relevant and favourable to line C for V and to line R for U, UM, Cn, TSE, Nm, Mi, and Mm. Individual heterosis was high for Dp and Dd.     

四倍体高粱与约翰逊草杂交种饲用品质分析

利用四倍体高粱品系"四沈甜"、不育系"四6A"和约翰逊草,配置"四沈甜"×约翰逊草、"四6A"×约翰逊草和"四6A"×"四沈甜"杂交种,分析了杂交种及杂种分离世代的不同生长阶段的杂种优势及饲草品质。结果表明,在孕穗期各供试材料粗蛋白质含量最高,杂交种蛋白质含量达到10%～15%,随着发育期的推进,含量有所下降。抽穗期,粗脂肪含量达到6.1%～7.9%。各材料的粗纤维含量都在30%以上,不同生长阶段差异不显著。单位能量值在抽穗期最高,达到18MJ/kg左右。综合各营养成分含量和单位能量分析,初步认为四倍体高粱与约翰逊草杂交种可以作为饲草应用,抽穗期为刈割和利用的最佳时期。     

科学养狐 走出困境

本文详细介绍了新源良种狐繁育场引进国内外科研成果,改良提高国产蓝狐质量,加大科技投入,保持和发挥优良种狐的遗传潜力和抓好基础建设,提高饲养管理的科技含量的成功经验。     

Differentiation of human umbilical cord mesenchymal stem cell into germ-like cell under effect of co-culture with testicular cell tissue

Supplements produced by mouse testicular cells (mTCs) and the interaction between cells can increase the differentiation rate of human umbilical cord mesenchymal stem cells (hUCMSCs) into the germ-like cells. We studied the differentiation rate of hUCMSCs into the germ-like cells under effect of mTCs co-culturing. Isolated hUCMSCs from postpartum human umbilical cords were cultured. Then, the expression of mesenchymal (CD73, CD90 and CD105) and haematopoietic (CD34 and CD45) markers of hUCMSCs were confirmed by flow cytometry. Then, the hUCMSCs were cultured in four distinct groups: (a) control, (b) co-culture until D0, (c) co-culture until D5 and (d) co-culture until D10, in order to differentiate into the germ-like cells. After 10 days, the expression of OCT4, VASA, Fragilis and SYCP3 genes were examined by Real-Time qPCR. The flow cytometry indicated a high expression of mesenchymal markers and a low expression of haematopoietic markers (CD73:98.6%, CD90: 99.1%, CD105: 99.5%, CD34: 4.22% and CD45: 2.54%). The expression of OCT4 decreased during the time while the expression of VASA, Fragilis and SYCP3 markers increased in the co-culture with testicular cells (p value <.05). Co-culture with mTCs may be used as an effective method to differentiate hUCMSCs into germ-like cells.     

成年小鼠雄性生殖细胞的冷冻保存

在含10％小牛血清（NBS）的DMEM培养基中，分别各添加5％，10％，15％，20％和25％的二甲基亚砜（DMSO）,丙二醇（PG），乙二醇（EG）和甘油（G），对成年小鼠睾丸生殖细胞冷冻保存；复苏后台盼蓝染色测定细胞复苏率。结果显示，5％－25％DMSO冻存液组的细胞复苏率分别为88.5%,88.0%,65.6%及51.3%;5%-25%PG冻存液组的细胞复苏率分别为87.2%,86.4%,79.0%,73.4%及40.1%.;5%-25%EG冻存液组的细胞复苏率分别为6.6%,80.9%,60.8%,51.3%及30.0%;5%-25%G冻存液组的细胞复苏率分别为86．5％，86．3％，65．3％，36．0％及31．4％。其中各抗冻剂5％和10％组的细胞复苏率最高，与15％组相比均存在显著或极显著差异。4种抗冻剂的最高细胞复苏率之间无显著差异。DMSO，PG，EG和G分别冷冻保存成年小鼠睾丸生殖细胞对的最小损失率分别为4．8％，6．1％，6．7％，6．8％。结果表明，采用慢速冷冻时，DMSO，PG，EG及G均适宜用作成年小鼠睾丸生殖细胞的抗冷冻剂，最佳使用含量均为5％－10％。成年小鼠睾丸生殖细胞分别在含5％－10％的DMSO，PG，EG和G的DMEM（含10％NBS）冻存液中，2步慢速降温，液氮储存，37℃水浴复苏，是一种具有较高复苏率的冷冻保存方法。     

北方蚕区第五批桑品种鉴定（山西点）试验报告

2011—2013年,山西省蚕业科学研究院对北方蚕区3个单位7个桑品种进行了鉴定。田间调查和实验室鉴定结果表明,7个参鉴桑品种生长势强、产叶量高,品质特性良好,在形态特征和生物学特性方面与对照存在不同程度的差异,而昌盛、9330两个品种的表现比较突出。     

杂种优势理论研究的回顾与展望

杂种优势是生物界的普遍现象，目前，其遗传理论的发展远落后实践中所取得的成就，这就限制了杂种优势的进一步利用和预测。本文在论述杂种优势遗传理论研究现状的基础上，对今后的发展作了展望。     

野生硬雀麦栽培驯化研究

通过硬雀麦Bromus rigidus与3种一年生黑麦草Lolium multiflorum和莜麦Avena nuda的品种比较试验,结果表明:硬雀麦产草量达76 095.0 kg/hm2,仅次于阿伯德多花黑麦草(77 589.0 kg/hm2),略高于邦德一年生黑麦草(74 212.5 kg/hm2),三者之间差异不显著(P>0.05);高于赣选1号多花黑麦草(67 033.5 kg/hm2)和莜麦(66 697.5 kg/hm2),差异极显著(P<0.01)。硬雀麦的播种量以73.3125 kg/hm2,行距15 cm为最佳,平均产量可达98 227.5 kg/hm2。硬雀麦可作为过渡带冬闲田种植的优良牧草。     

箭筈豌豆新品种DUS测试指南研制—测试性状评价和参照品种筛选

以国际植物新品种保护联盟(UPOV)制定的植物新品种DUS(distinctness, uniformity and stability)测试指南总则(TG/1/3)、箭筈豌豆DUS测试指南(TG/32/7)等技术文件为指导,对箭筈豌豆DUS测试指南的核心技术内容:测试性状和参照品种等开展了研究。在国内外共收集到51个箭筈豌豆品种,并进行连续2年的田间观测。观测性状总计31个,包括UPOV箭筈豌豆DUS测试指南中的23个性状,以及本实验发现有特异性的8个新增性状。对每个测试性状的表达状态、观测时期、测定方法、观测数量等进行了分级和详尽描述。共筛选出32个参照品种(国际21个, 我国11个),确定了123个表达状态。并对UPOV 箭筈豌豆DUS测试指南中“外种皮底色”和“种子形状”表达状态的分级进行了补充。本研究结果可为我国箭筈豌豆新品种 DUS 测试指南的制定奠定技术基础,对促进我国箭筈豌豆品种保护、审定和育种工作具有重要的意义。