小麦面粉沉淀值的微量快速测定(简报)

沉淀值(sedimentation value)是衡量小麦面粉蛋白质品质的一个重要指标。研究表明,沉淀值与面包的体积及面包得分有最密切的相关性。可用沉淀值测定法来估价小麦面粉的品质。许多育种单位都采用沉淀值测定法作为蛋白质品质育种的早代筛选法。按照 ICC-116标准,沉淀值测定需要最少3.2g 面粉,如果要在 F_2对单株进行测定,样品量显得大了些。因而有人发展了一些微量的沉淀值测定法。作者在联邦德国进修期间,对一私人育种公司发展的一种微量测定法进行了研究,现将结果简报如下。     

笃斯越桔硬枝扦插繁殖技术研究

采用笃斯越桔硬枝扦插,用生根剂处理插穗,并在不同的基质上进行扦插试验,结果表明:笃斯越桔硬枝扦插用河沙作为基质最好,生根剂ABT处理的插穗生根率最高。     

浅议我国绿色旅游

文章探讨了我国绿色旅游的兴起、内涵、特点和功能等,讨论了绿色旅游、生态旅游、自然旅游的区别与联系,分析了我国绿色旅游的发展现状和对策。     

沙门氏菌鞭毛蛋白属共同抗原表位的定位

用淋巴细胞杂交瘤技术研制成４株沙门氏菌属特异单抗ＣＢ８，ｄｅ７，ｃｃ６，ＤＤ４，在免疫转印试验中，证实它们所识别的抗原表位位于鞭毛蛋白上，ＥＬＩＳＡ相加试验及竞争试验显示，ＣＢ８和ｃｃ６与ｄｅ７，ＤＤ４识别的抗原表位不同，表明鞭毛蛋白的属共同抗原具有多种表位的特性。用胰蛋白酶消化鞭毛蛋白，ＳＤＳ－ＰＡＧＥ结果出现两条新带，分子量分别为４２０００（Ｆ４２），２７０００（Ｆ２７），长时间消化，最终只剩下Ｆ２７条带，它可抵制该酶的消化。对该酶切样品的免疫转印结果表明，沙门氏菌鞭毛蛋白属共同抗原表位出现于Ｆ４２和Ｆ２７上，而相应的沙门氏菌分型Ｈ抗原单抗或因子血清识别的表位也在Ｆ４２和Ｆ２７上都得到了证实。这为沙门氏菌鞭毛蛋白抗原的多样性及结构和功能研究提供了证据。     

一类空间分解问题

讨论了一类与区域分解算法有关的空间分解问题，将二阶问题的已有的空间分解结果推广到四阶问题的相应空间中。还证明了一致重迭性条件与Ｂａｄｅａ条件的等价性。     

中国姜瘟病的研究进展

姜瘟病是中国生姜生产上发生较为普遍的病害,是由青枯劳尔氏菌(Ralstoniasolanacearum)引起的。此病原菌寄主范围广,可侵染44个科300多种植物。菌体短杆状,在TZC选择性培养基上培养出现白边较宽和白边较窄的两种菌落。菌系划分为5个生理小种和5个生化型,中国的姜瘟菌主要属生理小种1号,生物型属II、III、IV。此病害是一种较难防治的土传病害,在高温、高湿、雨水多、氮肥过量的情况下发生较为严重。中国植病工作者对此病害作了大量的研究工作,对中国姜瘟病的病原菌、发病规律、及防治等研究进展作一综述。     

温柔欺诈何时休

在美国费城，有一位名叫John Wanamaker的大老板曾说过这样一句话：“我敢肯定我花在广告上的钱，有一半是被浪费掉了。但问题是，我不知道是哪一半。”     

芒萁马尾松林下可燃物分布及其燃烧性

2004年春季,在福建省闽清县白樟林业站辖区,对刚发生不久的火烧迹地进行调查,并在火烧迹地四周选择与过火区域林分状况相似的芒萁马尾松林,对林下芒萁及主要灌木的负荷量进行了调查。在此基础上,对芒萁马尾松林下可燃物分布及其燃烧性进行了分析,计算了一旦发生火灾林下可燃物可能释放的能量,并将芒萁马尾松林下地表可燃物的潜在能量与其他林分进行了比较。提出了降低此类林分火险等级的几种技术措施。     

GIS在生态土地分类中的作用

This paper depicted the physiographic landscape features and natural vegetation situation of study area (the eastern Jilin Province), and expatiates the definition, basic characters and its development of Ecological Land Classification (ELC). Based on the combination of relief map, satellite photography for study area and vegetation inventory data of 480 sample sites, a 5-class and a 15-class ecological land type map was concluded according to 4 important factors including slope, aspect, vegetation and elevation. Ecological Classification System (ECS) is a method to identify, characterize, and map ecosystems. The Ecological Land Type (ELT) was examined and applied initially in eastern Jilin Province. Foundation item: This paper was supported by Chinese Academy of Sciences “100 people” project and the Open Research Station of Changbai Mountain Forest Ecosystem. Biography: XIAO Bao-ying (1974-), female, postgraduate in Institute of Applied Ecology, Chinese Academy of Sciences, Shenyang 110016, P. R. China Responsible editor: Zhu Hong     

Seroprevalence of porcine and human influenza A virus antibodies in pigs between 1986 and 1988 in Hassia

1,268 sera collected from slaughtered pigs in Hassia (FRG) from 1986 to 1988 were tested for antibodies against porcine and human influenza A virus strains using the single radial haemolysis test (SRHT). Antibodies against the porcine strains (subtype H1N1) A/Swine/Arnsberg/1/81, A/Swine/Iowa/15/30 and A/New Jersey/7/76 were detected in 411 (32.4%), 318 (25.1%) and 304 (24.0%) of sera, respectively. Up to 1988 a slight increase (10%) in the seroprevalence to A/Swine/Arnsberg/1/81 was noticed, whereas the results obtained with the other strains showed little variation. Antibodies against the human H1N1 strain A/Singapore/6/86 were only found in sera collected 1987 and 1988 in rates of 1.6% and 3.0%. Serological indication of infections with the human H3N2 strains A/Victoria/1/75, A/Hong Kong/1/68 and A/Philippines/2/82 could be shown in 286 (22.6%), 178 (14.4%) and 135 (10.6%) of the serum samples. Within the three year period the rate of sera positive for antibodies against A/Philippines/2/82 increased from 6.5% to 23.0%, whereas no variation in the rates were found using the other H3N2 strains. Antibodies simultaneously against porcine (H1N1) and human (H3N2) virus strains were detected in 9.9% of all sera tested.