猪传染性胃肠炎病毒南京株纤突S蛋白基因的克隆与序列分析     

张素芳  何孔旺  贾云  倪艳秀  华荣虹  赵玉军 《动物医学进展》2003,24(3):93-97

参考 Genbank收录的 TGEV- Miller株的基因序列 ,自行设计合成 1对引物 (TGEVP5 /P6 ) ,对不同代次的 TGEV疫苗弱毒 STC3及种毒 、种毒 进行了 RT- PCR扩增 ,产物经琼脂糖凝胶电泳分析 ,均出现 1条大约 12 6 2 bp的目的条带 ,经 Eco R 酶切 ,都产生了 871bp和391bp左右的两个片段 ,与预期大小相符。将种毒 RT- PCR扩增目的条带回收纯化后克隆入PMD18- T载体中 ,转化宿主菌 DH5 α,挑选阳性克隆 (命名为 PTs) ,提取重组质粒 ,用 Hpa 、Eco R 对重组质粒进行酶切鉴定以及 PCR扩增 ,然后进行序列测定 ,并进行了序列分析 ,证实与国外标准毒株 Miller、Fs772 / 70、Purdue、TO14等有较高的同源性  相似文献   

CCC对葡萄试管苗生长的影响     

廖康  李疆 《新疆农业大学学报》1995,(2)

ＣＣＣ对葡萄试管苗的茎叶生长有显著的抑制作用，茎的高度、节数及节间长度均有明显减少；ＣＣＣ对生根率没有明显影响，但对插段的生根数量有较大的影响，在一定浓度范围内（２０～８０ｍｇ／Ｌ）ＣＣＣ处理的生根数量有所增加，其中以４０ｍｇ／Ｌ时增加最多，为８．６７～８．９５条／段。但ＣＣＣ对根系伸长有明显的抑制作用，随着ＣＣＣ浓度的升高根长逐渐变短；从干、鲜重的变化来看，ＣＣＣ处理后墓叶的干、鲜重是随着浓度的升高而减少，但根系的干、鲜重在０～４０ｍｇ／Ｌ范围内呈略增加的趋势，４０ｍｇ／Ｌ以后则大幅度减少。  相似文献   

激素诱乳技术推广应用及其效益分析   总被引：1，自引：0，他引：1  

郭锁链  孙树春 《畜牧与兽医》1995,27(1):6-7

１９８７～１９９３年７年间用＂诱乳激素＂处理空怀奶牛１３０２头次，诱乳成功率达８６．ｌ％，并有８１．６％的牛恢复正常的生理周期，配种后的受胎率达７７．４％，直接经济效益为１５０余万元。本试验表明，对因饲养管理，生殖疾病等原因引起不孕及无乳的成年母牛，用＂诱乳激素＂进行人工诱乳是完全可行的且经济效益是十分显著的。  相似文献   

抗霉菌素“120”与杀灭菊酯混用防治效果试验     

谢德龄  倪楚芳 《中国生物防治》1985,(2)

抗霉菌素“120”是一种新的农用抗菌素,防治农作物上多种病害都有效。实验室试验证明;本剂与杀灭菌酯混用,对防治病害和虫害的效果没有不良影响,因此可以减少打药次数,有一定经济意义。  相似文献   

Regulation of early flowering in Pinus banksiana     

Cecich RA  Kang H  Chalupka W 《Tree physiology》1994,14(3):275-284

Seedlings of three families of jack pine (Pinus banksiana Lamb.) were subjected to 16 combinations of photoperiod, growth environment (outdoors, greenhouse and biotron) and gibberellin (GA(4/7)) treatment. After 14 months, which included two dormancy induction periods, ovulate flowering was observed. There was a strong positive correlation between flowering and seedling height; female flower production was stimulated by both a declining photoperiod during bud development and GA(4/7) treatment; and there was an interaction between GA(4/7) treatment and family, such that the difference in flowering intensity between a late-flowering and an early-flowering family was eliminated by GA(4/7) treatment. The results suggest that the genetic control over the time of onset of flowering, and GA(4/7)-induction of flowering depend on a common mechanism.  相似文献   

以电导法配合Log istic方程确定茶梅‘小玫瑰’的抗寒性   总被引：31，自引：4，他引：31  

徐康  夏宜平  徐碧玉  林田  杨霞 《园艺学报》2005,32(1):148-153

 摘　要: 以不同处理时间、不同低温处理下茶梅‘小玫瑰’叶片的电解质外渗率(REC) 变化作曲线,并结合Logistic方程分别计算茶梅的半致死温度(LT50 ) , 结果发现在低温处理6 h以上, 茶梅叶片的REC均随着处理温度的降低而呈“S”形上升, 由此计算出“S”形拐点对应的温度即为茶梅叶片的LT50 , 其温度值在- 1215℃至- 14℃之间, 这可认为是茶梅抗寒能力的重要指标。关键词:  相似文献   

桃果实絮败机理及减缓措施   总被引：5，自引：2，他引：5  

邵兴锋  屠康  曹燕  李一青 《果树学报》2005,22(2):149-153

桃果实在8℃以下的低温环境中贮藏2周以上极易受冷害,后熟过程中表现出果肉质地发绵、汁液减少等 絮败现象。絮败的产生主要是果胶甲酯酶(PE)和多聚半乳糖醛酸酶(PG)活性变化不平衡导致果胶质正常降解受 阻,形成凝胶所致。综述了近年来对于桃和油桃絮败机理方面的研究成果,从絮败发生的机理、絮败程度检测以及在 低温贮藏中如何减缓絮败发生的措施等方面进行了论述。认为影响桃果实絮败的主要因素是贮藏温度、品种、成熟 度等。絮败的评价主要用出汁率等方法,在贮藏中可以采用气调、中途加温、外源乙烯处理、延期贮藏等措施减缓絮 败发生。提出了需要近一步研究的内容。  相似文献   

Effect of cGMP on voltage-gated potassium channel in pulmonary artery smooth muscle cells from rats exposed to chronic hypoxia     

ZHANG Yong-chang  NI Wang  ZHEN Guo-hua  ZHANG Zhen-xiang  XU Yong-jian 《园艺学报》2003,19(8):1012-1015

AIM: To investigate the effect of cGMP on voltage-gated potassium channel in pulmonary artery smooth muscle cells (PASMCs) from rats exposed to chronic hypoxia. METHODS: (1) Wistar rats were randomly divided into control group (group A) and chronic hypoxia group (group B). Then group B received hypoxia 8 hours per day for 4 consecutive weeks. (2) Single PASMC was obtained via acute enzyme separation method. (3) Conventional whole-cell patch clamp technique was used to record resting membrane potential (Em) and ion currents of voltage-gated potassium channel. The changes of ion currents of voltage-gated potassium channel before and after applying cGMP (1 mmol/L), an agonist of protein kinase G (PKG), and cGMP plus H-8 (1 mmol/L), an inhibitor of PKG were compared between two groups. RESULTS: The Em of group B were significantly lower than that of group A. The ion currents of voltage-gated potassium channel in group A and group B were all significantly inhibited by cGMP [control group: from (118.0±5.0) pA/pF to (89.9±16.5) pA/pF, n=6, P＜0.05;chronic hypoxia group: from (81.0±5.0) pA/pF to (56.8±9.1) pA/pF, n=6, P＜0.05]and these effects were reversed by H-8 [control group: from (119.2±10.3) pA/pF to (117.8±9.1) pA/pF, n=6, P＞0.05;chronic hypoxia group: from (96.8±6.2)　pA/pF to (98.0±2.2)　pA/pF, n=6, P＞0.05]. CONCLUSIONS: The currents of voltage-gated potassium channel was inhibited by chronic hypoxic. The inhibitory effect of cGMP on currents of voltage-gated potassium channel in PASMCs from both normal and chronic hypoxic rats may be probably through the phosphorylation of voltage-gated potassium channel.  相似文献   

Importance of Cell Wall Degrading Enzymes Produced by Fusarium graminearum during Infection of Wheat Heads     

Wanyoike Mary Wanjiru  Kang Zhensheng  Heinrich Buchenauer 《European journal of plant pathology / European Foundation for Plant Pathology》2002,108(8):803-810

Cytological studies were carried out to elucidate the importance of cell wall degrading enzymes (CWDE) during infection of wheat spikes by Fusarium graminearum. Scanning electron micrographs revealed that at 6–24 hours after inoculation (hai) of single spikelets with macroconidia of F. graminearum, the fungus germinated by forming several germ tubes and developed a dense hyphal network in the cavity of the spikelet. At 24–36hai, the fungus formed infection hyphae which invaded the ovary and inner surface of the lemma and palea. Transmission electron microscopical studies revealed that the fungus extended inter- and intracellularly in the ovary, lemma and rachis and caused considerable damage and alterations to the host cell walls. In different tissues of healthy and F. graminearum-infected wheat spikes the cell wall components cellulose, xylan and pectin were localized by means of enzyme-gold and immuno-gold labelling techniques. Localization of cellulose, xylan and pectin showed that host cell walls which were in direct contact with the pathogen surface had reduced gold labelling compared to considerable higher labelling densities of walls distant from the pathogen–host interface or in non-colonized tissues. The reduced gold labelling densities in the infected host cell walls indicate that these polysaccharide degrading enzymes might be important pathogenicity factors of F. graminearum during infection of wheat spikes. The results revealed that, infection and colonization of wheat spikes by F. graminearum and reactions of infected host tissue were similar to those reported for F. culmorum.  相似文献   

枯草芽孢杆菌B—916防治水稻纹枯病的田间试验   总被引：35，自引：4，他引：35  

陈志谊  高太东 《中国生物防治》1997,13(2):75-78

１９９２～１９９４年在田间小区试验比较两个拮抗细菌（Ｂ－９１６、Ｐ－９１）和井岗霉素对水稻纹枯病的防治效果。１９９４～１９９５年在江苏省３个基点上进行了Ｂ－９１６防治纹枯病的大面积示范试验。Ｂ－９１６发酵液在田间对水稻纹枯病的为害有较强的控制能力，发酵含菌量为２．５４×１０１１～２．５４×１０１２ｃｆｕ／ｍＬ时，用量３．７５Ｌ／ｈｍ２的防治效果为５０．０％～８１．０％。  相似文献