金针菇菌丝生长量与可溶性蛋白含量变化比较研究

对6株金针菇菌丝在发育过程中的生长变化规律作了比较研究。结果表明,不同菌株在不同培养时期菌丝的生长量与各自的可溶性蛋白含量的变化有密切的关系;而在同一培养时期,各菌株的菌丝生长量与可溶性蛋白含量无明显的关系。杂交菌株Z_(76)的菌丝生长量和可溶性蛋白含量高于双亲,可与杂交19号相媲美。     

“耳螨净”滴液治疗狐耳痒螨病的试验研究

用“耳螨净”滴液,对自然感染耳痒螨的狐只进行治疗试验。结果：离体杀螨试验,螨虫平均麻痹时间为１５ｍｉｎ,平均死亡时间为５１ｍｉｎ;狐体杀螨试验中,耳内给药后１ｈ狐开始变为安静,第３ｄ搔痒症状消失。间隔７ｄ两次给药,不仅可以杀死成虫,而且能够杀死由螨卵继续孵出的幼虫和茧虫。同时对继发的细菌感染引起的耳内炎症有显著疗效。     

月季黑斑病的流行与防治

本试验采用对样枝分级,且不断更替的取样方法,进行了14个月的月季黑斑病流行的系统调查。月季黑斑病在广州地区周年发生,有2个主要的流行时期,分别在4月下旬至7月上旬及9月下旬至10月下旬。其流行与温度、湿度、降雨量及降雨次数密切相关,在适宜的温度(20—27℃)下,降雨或相对湿度高峰10—20天内出现病叶率高峰。田间10种药剂防病试验,敌力脱效果最高,达91.2％;施保克次之,为86.7％。百菌清也具有良好的防效,3年均在70％以上;如果与营养液1号混合喷雾,不仅防效提高,还可以促进月季生长、增加花枝数量和提高切花质量。     

白背飞虱生活史观察及其在测报技术上的应用

贵州惠水地区白背飞虱Sogatella furcifera(Horvath),在室内自然变温条件下,1980—1983年饲养结果均可完成6个完整世代,其中1年可繁殖7代。从6010头个体中加权法算出在不同温度下的卵历期6.16—16.67天,若虫期11.17—20.7天,成虫历期变幅较大6.05—36.32天。本试验计算的白背飞虱温度与发育时间的理论公式,验证了惠水4年来多点系统调查的田间实际发生期。根据田间发生规律,一般以第二代为主害代,预报的重点应放在成虫迁入大田高峰期和迁入量,用本理论公式和田间繁殖系数,即可计算出下一代初龄若虫高峰期和发生量,做到准确及时和经济有效地进行防治。     

氮抑制剂对蔬菜产量和硝态氮含量的影响

在单施化肥的基础上,分别添加5种氮抑制剂,研究其对蔬菜硝酸盐、亚硝酸盐含量及产量的影响。结果表明吡啶、咪唑和双氰胺3种氮抑制剂的施用对降低蔬菜硝酸盐含量效果明显,降低幅度为9.6%～31.1%,而对蔬菜产量的影响不大;各处理的亚硝酸盐含量均很低;氢醌、儿茶酚两种氮抑制剂的施用效果不明显。     

均匀设计在无籽西瓜快繁研究中的应用

采用均匀设计U9(96)方案研究农友新 1号无籽西瓜组培增殖培养基配方的植物激素用量 ,在 6-BA、IBA、IAA等 3因素 9水平试验方案中 ,只用 9个处理的较少试验次数便获得成功。分析结果认为 ,获得≥ 0 5cm正常芽的增殖培养基优化配方为改良MS + 6-BA1 80 2 8(mg·L- 1,下同 ) +IAA1 6。     

粉锈宁缓释剂防治玉米丝黑穗病

玉米丝黑穗病是贵州省玉米的主要病害之一,每年都造成严重损失。按常规使用0.08％粉锈宁农药直接拌干玉米种防治此病,防效差,易产生药害。将粉锈宁与聚乙烯醇等复配成缓释剂后拌萌动的玉米种,解决了药害问题,还提高了防效。     

Evaluation of a multiplex real-time RT-PCR for quantitative and differential detection of wild-type viruses and C-strain vaccine of Classical swine fever virus

Classical swine fever virus (CSFV) is the causative agent of classical swine fever (CSF), one of OIE listed diseases. Most of the currently available detection methods do not allow discrimination between wild-type CSF viruses and the vaccine strains. This study was designed to develop a multiplex real-time RT-PCR for the quantitative and differential detection of wild-type viruses and C-strain vaccine widely used in China. CSFV specific primers and two differently labeled TaqMan probes for the differentiation of wild-type viruses from C-strain vaccine were designed in the 5'-untranslated region of the viral genome of CSFV. The two TaqMan probes specifically hybridize wild-type viruses of different subgroups and C-strain vaccine, respectively, in the multiplex real-time RT-PCR, with no cross-reaction to a number of non-CSFV porcine viruses. The sensitivity of the assay for detecting wild-type and C-strain-type vaccine viruses was determined to be 41.8 and 81.5copies/microL viral RNA, respectively. Completely correct differentiation of wild-type viruses from C-strain vaccine was achieved when testing reference strains and characterized field isolates of CSFV in China. The multiplex real-time RT-PCR was able to detect the viral RNA in the whole blood samples of experimentally infected pigs as early as 2 days post-infection, 3 to 4 days prior to the onset of clinical signs in co-housed pigs. The agreements between the multiplex real-time RT-PCR and a multiplex RT-nested PCR for detection of wild-type and C-strain-type viruses were 96.9% and 100%, respectively, when detecting 106 different field samples. There is a positive correlation between the titers of C-strain vaccines titrated in rabbits and RNA copies quantitated by the multiplex real-time RT-PCR. The novel assay described here is rapid and sensitive, and is useful for differentiating field strains and C-strain of CSFV in China.     

Expression and significance of PTEN in canine mammary gland tumours

To explore the expression and clinical importance of the anti-oncogene phosphatase and tensin homologue deleted on chromosome 10 (PTEN) in canine mammary gland tumours, PTEN expression was compared in 50 cases of canine mammary tumour and four examples of normal mammary tissue using real-time quantitative PCR. PTEN expression was similar in benign mammary tumours and normal mammary tissues (P>0.05), but was lower in malignant tumours than in normal mammary tissues or benign mammary tumours (P<0.001). PTEN expression was also low in the lymph node metastases of malignant mammary tumours. The expression profile of PTEN in malignant mammary tumours compared to those without lymph node metastasis varied significantly. Low-level PETN expression might play an important role in carcinogenesis and the progression of canine mammary tumours, and PTEN protein detection might be useful in evaluating tumour development and prognosis.     

纸浆模塑餐具热压干燥过程的研究

该文对纸浆模塑餐具热压干燥工艺过程进行了分析,在此基础上建立了模具热传导方程,采用分离变量法推导出模具热传导方程的解析解,同时应用Matlab软件进行数值求解。根据热传导方程的解析解、数值解计算的模具表面温度值与与实测值较为吻合。对模具的传热分析为模具结构设计及加热管布置提供了理论依据。根据热传导方程并结合生产实际经验,推导出相应的湿坯热压时间,为热压过程的控制提供了基础。