昆虫生态学问题及植物害虫数量消长的条件

1.环境因子及其分类 所有的动物有机体都是其生活环境的不可分离的一部份。因之决不能把有机体和代表其生活环境的条件总和脱离来看。 环境条件的总和是由各项因子综合影响的结果而形成的;这些因子共同作用於有机体,同时也就造成生活环境的某些特点:这些环境因子或生态因子可以分为下列几方面: (1)与影响有机体的自然现象有关的自然因子或原始因子。这类环境因子可分为下列三类:     

生物原生长刺激物对植物产量和化学组成的影响

我们在研究農作物的植物性蛋白质方面,应用了各种刺激物,目的是要查明这些刺激物对植物中蛋白质的累積和转化,以及对可能提高植物的籽实和绿色體产量的影响。所用刺激物为:1/7000M的天门冬酸和琥珀酸的水溶液,以及按下列方法调制的稀释後的种苗浸出液。把每种作物的种子置於黑暗中湿润的滤纸上,在室温下经5天即已发芽。将发芽的种苗放在带有浸於水中的排水管並蓋有软木塞的玻璃瓶中,将此瓶放入冰箱,在+2°的温度下放上12—15天。此後     

用RAPD法研究火炬松愈伤组织发生的遗传特性(英文)

体外培养对于植物的快速繁殖是非常有效的。和其它一些松果类硬木植物一样,火炬松的体外培养成功率却一直很低。本工作研究了不同的基本培养基和低温条件对于火炬松Ｊ－５６, Ｓ－１００３, ａｎｄ Ｅ－４４０等三个品系的成熟合子胚形成愈伤组织、分化出芽、成苗的影响。在不同的基本培养基条件下芽分化的程度差异很大。合子胚经过９－１２周培养,开始分化,形成具有器官发生的愈伤组织（Ｆｉｇ．２ａ）。分化后３周,开始诱导出芽（Ｆｉｇ．２ｂ）,芽的生长快慢不同（Ｆｉｇ．２ｃ,ｄ）。同一个愈伤组织上会生出几个芽来（Ｆｉｇ．２ｅ）。在添加有ＩＢＡ和ＢＡ的ＴＥ培养基上芽生长最快（Ｆｉｇ．１）。低温条件持续 １５天,能增加芽的数量和分化的程度（Ｔａｂｌｅ１）。上述培养基中增加ＧＡ３时表明,ＧＡ３对于根的诱导有决定性的作用。将９８株再生苗转移到特殊的混合土壤上;成活了７５株苗（Ｆｉｇ．２ｆ）。以这三种火炬松的再生苗尖为材料制备ＤＮＡ。用２０个引物进行ＲＡＰＤ分析,结果表明：这三种火炬松苗的扩增产物是相同的（Ｆｉｇ．２ｇ,ｈ＆ｉ）。这说明：用愈伤组织克隆植株的过程中没有引起植物遗传变异。     

用琼脂糖凝胶制备电泳— 冻融法纯化质粒DNA

随着基因工程研究的不断发展，DNA 做 为一种实验材料要求纯化方法更加简便，质量 更高。目前关于质粒DNA的纯化方法已有许 多报道fs-5I。国外多采用氯化艳密度梯度离心 法，国内则限于条件，很少应用此法。我们建 立了琼脂糖制备电泳— 冻融法，以纯化质粒 DNA及DNA的酶切片段。方法简便易行，而 且效果良好。     

用琼脂糖凝胶制备电泳——冻融法纯化质粒DNA

随着基因工程研究的不断发展,DNA做为一种实验材料要求纯化方法更加简便,质量更高。目前关于质粒DNA的纯化方法已有许多报道。国外多采用氯化铯密度梯度离心法,国内则限于条件,很少应用此法。我们建立了琼脂糖制备电泳——冻融法,以纯化质粒DNA及DNA的酶切片段。方法简便易行,而且效果良好。     

An integrated database on ticks and tick-borne zoonoses in the tropics and subtropics with special reference to developing and emerging countries

Tick-borne zoonoses (TBZ) are emerging diseases worldwide. A large amount of information (e.g. case reports, results of epidemiological surveillance, etc.) is dispersed through various reference sources (ISI and non-ISI journals, conference proceedings, technical reports, etc.). An integrated database-derived from the ICTTD-3 project ( http://www.icttd.nl )-was developed in order to gather TBZ records in the (sub-)tropics, collected both by the authors and collaborators worldwide. A dedicated website ( http://www.tickbornezoonoses.org ) was created to promote collaboration and circulate information. Data collected are made freely available to researchers for analysis by spatial methods, integrating mapped ecological factors for predicting TBZ risk. The authors present the assembly process of the TBZ database: the compilation of an updated list of TBZ relevant for (sub-)tropics, the database design and its structure, the method of bibliographic search, the assessment of spatial precision of geo-referenced records. At the time of writing, 725 records extracted from 337 publications related to 59 countries in the (sub-)tropics, have been entered in the database. TBZ distribution maps were also produced. Imported cases have been also accounted for. The most important datasets with geo-referenced records were those on Spotted Fever Group rickettsiosis in Latin-America and Crimean-Congo Haemorrhagic Fever in Africa. The authors stress the need for international collaboration in data collection to update and improve the database. Supervision of data entered remains always necessary. Means to foster collaboration are discussed. The paper is also intended to describe the challenges encountered to assemble spatial data from various sources and to help develop similar data collections.