重组hIL-2表达载体的构建及在毕赤酵母中的表达

本试验根据hIL-2氨基酸序列、三维结构及其与受体IL-2R结合机制,设计并合成IL-2Rα亚基结合位点修饰性hIL-2基因片段。合成的修饰性hIL-2基因序列被插入真核表达载体pPIC9K,并转化入毕赤酵母基因组中。经筛选得到阳性重组子后,通过诱导培养得到了表达产物。对表达产物进行Elisa初步测定,结果成功表达出重组hIL-2,表达水平达0.93g/L。本项研究为进一步开展IL-2Rα结合位点修饰性hIL-2的生物活性研究奠定了基础。     

基于ACO-SVM的粮虫特征提取研究

[目的]研究基于ACO-SVM的粮虫特征提取,探讨粮虫特征提取的可行性。[方法]通过分析储粮害虫图像识别系统中的1个关键环节——特征提取,提出把支持向量机(Support vector machine,简称SVM)算法中交叉验证训练模型的识别率作为储粮害虫特征提取评价准则的1个重要因子,将蚁群优化算法(Ant Colony Optimization,简称ACO)应用于粮虫特征的自动提取。[结果]该算法从粮虫的17维形态学特征中自动提取出面积、周长等7个特征的最优特征子空间,采用参数优化之后的SVM分类器对90个粮虫样本进行分类,识别率达到95%以上。[结论]该研究表明蚁群优化算法在粮虫特征提取中的应用是可行的。     

河北省冬麦北界北移决策支持系统研究

[目的]研究河北省冬麦北移决策支持系统(Decision Support System for"Northing of Winter Wheat"in Hebei,DSSNWWH),为提高农业系统决策的科学性和信息化程度提供方法。[方法]介绍了河北省冬麦北移决策支持系统的功能、开发流程、运行向导以及输入输出方式,并对该系统的相关预测结果进行了实际验证。[结果]该研究建立的决策支持系统可以在以往气象数据或当地气象预报的基础上,对某一冬小麦品种在河北省北部某一地区能否安全越冬及其生长发育状况进行预测,并给出相应的栽培管理措施,用户可根据预测结果来判断该品种在这一地区能否种植。[结论]该研究建立的DSSNWWH可有效地辅助决策者进行决策,为冬小麦的北移提供科学的指导。     

植物品种权入股问题探析

植物品种权入股是农业知识产权与经济的结合,有利于加快品种权的实施应用,增强种子企业的核心竞争力。文章在对植物品种权入股内涵界定的基础上,探讨了植物品种权入股的三种模式,利用植物品种权入股选择模型,揭示植物品种权入股的实现机理,为植物品种权入股提供一种思维方式和理论图示,并提出了植物品种权入股的保障措施。     

Culicoides trapping with Rothamsted suction traps before and during the bluetongue epidemic of 2006 in Belgium

The collection of biting midges was taking place some months before the first bluetongue outbreak in Belgium in August 2006. The Walloon Agricultural Research Centre had been monitoring aphid populations at two sites annually in Belgium (Gembloux and Libramont), using two stationary ‘12-m’ Rothamsted suction traps. For the Gembloux trap, collections of insects captured daily from 11 May 2006 onwards were already available at the time of the outbreak. An examination of these samples revealed the presence of Culicoides, some species of which are considered as potential vectors of the bluetongue virus (BTV). The trapping was therefore extended beyond the normal aphid activity period and the Culicoides captured were identified to species level. From 11 May to 31 December 2006, the Gembloux trap caught 664 Culicoides specimens belonging to 19 species comprising known BTV-vectors. The second trap, at Libramont, was reactivated from 12 September to 13 October and caught 97 specimens belonging to nine species, all of which had been found at the Gembloux site. Among the 19 species identified, four were new to Belgian fauna: Culicoides achrayi, C. deltus, C. lupicaris and C. newsteadi. This paper examines the overall phenology and the physiological status of Culicoides in 2006 before and during the bluetongue epidemic. It discusses the potential of the Rothamsted suction trap to monitor Culicoides.     

Vector analysis in the study of the nutritional status of Philodendron cultivated in compost-based media

Compost (CP) made from 70% ligno-cellulosic compounds and 30% sewage sludge was studied as a component of growing media in a 6-month Philodendron cultivation. CP's agronomic viability was evaluated via four plant-growth media containing 25–50–75–100% CP and white sphagnum peat (WP) in comparison to a commercial substrate with white and black peat. Plant nutrition conditions were investigated by determining macro- (TKN, P, K, Ca, Mg and micronutrients (Mn, Fe, Cu, Zn, Na) and heavy metals (Ni, Cd, Cr, Pb) in roots and shoot tissues. Data were compared by vector analysis against control. Even if no leaf injuries were visible after 6-months’ growth, a CP ratio of up to 50% caused growth depression of canopy tissues, as attested by the 37 and 36% reduction in total leaf dry weight and leaf area, respectively. Root growth decline was also notable at 25% CP, where 38% root dry weight reduction implied a significant increase (46%) in shoot–root dry weight ratio. The investigation on nutrient tissue content showed high accumulation of Ni, Fe, Cr, Zn, Cd, Mn, Mg and P in roots; Mg appeared related to K deficiency. Above-ground nutritional status showed a severe lack of P, Mg and Mn. Vector analysis suggests the sewage sludge CP in Philodendron pot cultivation produces many such effects like direct toxic action and antagonistic action, resulting in a general nutrient imbalance in plants.     

棉花生长素应答因子ARF3功能的初步分析

生长素应答因子(auxin response factor,ARF)是转录因子的一个家族,在生长素信号传导途径中起着关键的作用。通过GenBank上登录的序列设计引物,利用RT-PCR技术扩增得到了陆地棉生长素应答因子ARF3的全长序列,并构建到植物表达载体pCAMBIA1301上,借助真空渗透转化技术,在农杆菌GV3101介导下转化模式植物拟南芥,经潮霉素筛选,得到了批量的转基因植株。通过PCR技术,检测到目的基因成功整合到拟南芥基因组中,RT-PCR检测到了目的基因在转基因植株中得到表达。     

水稻隐花色素基因Cry1a/Cry2/Cry1bRNAi表达载体构建及遗传转化研究

构建一个包含3个水稻隐花色素基因片段的RNAi表达载体pSC 1301-347-Cry1aCry2Cry1b并转化水稻,以期导致Cry1a、Cry1b与Cry2集体沉默,观察它们对水稻重要农艺性状的影响.结果表明,转基因水稻开花期显著延迟,结实率骤降,株高增加,剑叶变短,谷粒变长、变宽；而剑叶宽、穗长与对照无显著差异.     

甘蔗锌指蛋白基因ShSAP1的RNAi载体构建及对甘蔗的转化

植物中具有A20/AN1锌指结构域的蛋白参与了逆境应答,为研究甘蔗A20/AN1型锌指蛋白基因ShSAP1的功能及在甘蔗抗逆育种方面的价值,本研究通过构建ShSAP1基因的RNAi载体并进行甘蔗的遗传转化,以期通过反向遗传学进行ShSAP1的功能分析。将ShSAP1锌指编码区片段分别以正向和反向插入到中间载体pTCK303内含子的两侧,构建中间载体pTCK-iShSAP1,而后把干扰片段连入pCAMBIA-GUS中,获得RNAi表达载体pCAMBIA-iShSAP1,将该载体转导根癌农杆菌EHA105,通过农杆菌介导法侵染甘蔗胚性愈伤组织,并对部分转化幼苗进行了初步的PCR鉴定。经过限制性内切酶分析和测序验证,RNAi载体pCAMBIA-iShSAP1构建成功;转化幼苗经PPT抗性筛选后,获得了58株抗性植株,对抗性幼苗进行了Bar基因的PCR检测,得到6株PCR阳性植株。本研究完成了ShSAP1的RNAi载体构建及对甘蔗的遗传转化,为ShSAP1的功能研究打下了一定的基础。     

解决农村养老中的非物质福利——基于M庄老人协会的实证研究

目前,农村老人越来越重视非物质福利。当前要改变农村老人的弱势群体地位、增强非物质老人福利,其中投入相对较低且有效的方式莫过于将农村老人组织起来建立老人协会。福利需求、村庄共同体的存续、第三种力量及农村精英的呼吁与领导等因素是老人协会得以建立的条件。对于"原子化状态"的村庄,则需要通过外部力量的介入解决老人协会建立过程中村民集体行动的初试成本问题。