两种硼肥对油菜新品种生长发育及产量的影响

两种不同含量的速溶硼肥，solubor和宽甸硼砂施用于油菜新品种中双9号、华双3号、中油杂2号和华杂3号的田间试验结果表明，施硼增加油菜苗期、越冬期、初花期干物重，增加株高、主花序长度、分枝数、单株角果数、粒数和粒重，而叶数、根茎粗和千粒重变化不明显；不同施硼菜籽产量平均增加5．7％～20．1％，喷施等量0．075％、0．10％、0．15％硼肥溶液，solubor优于宽甸硼砂，增产率分别为13．3％、18．3％、20．1％和5．7％、9．9％、15．2％；喷施等量有效硼时，两种硼肥的油菜单株粒重及菜籽产量均相近。表明两种硼肥对双低常规油菜与双低杂交油菜均有相似的显著增产效果，其增产率取决于有效硼施用量；在低硼土上，可满足双低油菜产量达2500～2800kg／hm^2的硼素需求为每公顷喷施宽甸硼砂5．7kg或solubor硼肥2．85kg。     

Antitumor effects of HSV-tk and cytosine deaminase double suicide gene mediated by adenovirus on cholangiocarcinoma cells in vitro

AIM: To study the antitumor effects of HSV-tk and cytosine deaminase double suicide gene system on cholangiocarcinoma cells in vitro. METHODS: Recombinant adenovirus vector carring HSV-tk and cytosine deaminase double suicide gene was constructed and was transfected into QBC939 huamn cholangiocarcinoma cells. The antitumor effects were observed in vitro in comparison with a single suicide gene system. RESULTS: By transfection, HSV-tk and (or) cytosine deaminase double suicide gene gained high expression in tumor cells. Compared with single suicide gene system, this double gene system presented higher sensitivity, stronger antitumor effect and bystander effect. CONCLUSION: HSV-tk and cytosine deaminase double suicide gene system has a powerful antitumor effect on cholangiocarcinoma cells.     

木本泥炭促进设施番茄生长和改良土壤的效果

针对设施菜田土壤连作障碍、蔬菜品质降低等问题,以北京郊区春大棚番茄为研究对象,通过基施木本泥炭及其他添加物料作土壤调理剂,研究其对番茄产量、品质以及设施土壤改良效果的影响。结果表明:木本泥炭+苛性钾处理较常规施肥处理番茄产量显著增加16.73%,果实VC含量显著增加55.77%,同时明显增加了耕层土壤速效磷、钾养分含量,提高了p H值,而单施木本泥炭、木本泥炭+米糠菌剂处理与常规施肥处理均无显著差异。施用木本泥炭及其他添加物料均有降低土壤表层盐分累积的趋势。综上,施用木本泥炭及其他配合物料对设施番茄生长以及土壤改良有良好的促进作用,其中木本泥炭+苛性钾处理效果最佳。     

‘More crop per drop’: how to make it acceptable for farmers?

In countries facing water scarcity, governmental water agencies try to transfer this constraint to farmers, e.g. by encouraging them to shift from traditional to localized irrigation methods to save water. However, water shortage is often much less a problem for farmers than soil limitations, their objective being mostly to maximize their income per cultivated area (US$ per hectare rather than per cubic meter of water). This discrepancy can only be solved if governments find ways to ‘transfer’ water scarcity, e.g. through economic incentives such as water pricing and/or subsidies. The aim of this study was to address the question of how to match the interest of both water managers and farmers. We aimed particularly at evaluating whether shifting to drip irrigation is a relevant way to save water and increase farmer's income.Our analysis was based on the interactive impacts among economic, environmental, technical and methodological parameters on the net productivity of two crops. We focused on the case study of Turkey considering two crops with contrasted gross productivity, tomato and cotton, characterized by partial vegetation cover during a large part of crop cycle. A 3D crop energy balance model was applied showing that crop transpiration is increased by up to 10% when shifting from furrow to drip irrigation. These results were used to correct the maximal evapotranspiration (ET_m), estimated with the simple “crop coefficient” (K_c) method, and then used to enhance net productivity estimation both for furrow and drip irrigation.The results suggest that water managers and farmers share a common interest in adopting drip irrigation of tomato. Inversely, interests divergence may increase with low/medium value crops as cotton; the combination between water pricing and subsidies could be a way of agreement, but it would require subsidies for irrigation equipment of at least 40%, for low water tariffs, to 60%, for high water tariffs, to make the transfer from furrow to drip irrigation acceptable. This approach appeared generic enough to be applied for other economic, technical or environmental conditions, to modernize irrigation by harmonizing constraints faced by water managers and farmers.     

成型参数对有粘结剂成型玉米秸秆燃料密度与强度的影响

为探讨高钙粉煤灰复合粘结剂对玉米秸秆原料成型密度和强度的影响,采用闭式冲压成型装置对添加高钙粉煤灰复合粘结剂的玉米秸秆进行成型实验研究,分别考察压力、温度、粒度和含水率对成型燃料的影响,并给出了最佳的成型压力范围。结果表明:玉米秸秆在压力为32～50MPa的范围内,加热温度85℃,物料含水率在12%以下,平均粒度为2mm的颗粒,能实现较好的有粘结剂成型,密度和强度基本符合工业要求。     

高剂量性信息素环境对草地贪夜蛾求偶和交配行为的影响

本文在风洞中模拟形成高浓度性信息素Z7-12:Ac、Z9-14:Ac和 Z11-16:Ac 环境,研究草地贪夜蛾Spodoptera frugiperda (Smith)的求偶和交配行为,为进一步开发交配干扰技术提供技术参数和依据。研究结果表明,在高剂量性信息素环境下,草地贪夜蛾雄蛾的暗期活动时间延后,而雌蛾的活动节律则没有变化,雌雄蛾之间产生了活动节律的时间差。同时,雌雄交配率和交配持续时间显著下降,交配日龄则显著延迟2 d。由于交配日龄延迟,产卵量及其孵化率也相应降低。性信息素喷射时间间隔对草地贪夜蛾性信息素释放滴度有显著影响,当间隔时间为5、10、20 min时,雌蛾释放的性信息素滴度显著下降,以5 min为最低。因此,高剂量性信息素环境不仅影响雄蛾对性信息素的定向,对雌雄蛾间化学通讯和交配也有显著影响。     

鸭病毒性肝炎研究进展

鸭病毒性肝炎是由鸭肝炎病毒(DHV)引起雏鸭的一种传染病,具有发病急、传播迅速、病程短、病死率高等特点,临床上主要表现为食欲减退、神经症状、突然死亡和肝脏肿大出血.病原有3种,其中Ⅰ型鸭肝炎病毒在世界范围内流行,Ⅱ型和Ⅲ型鸭肝炎病毒分别局限于英国和美国.不同血清型毒株具有不同的理化和生物学特性,且无免疫交叉反应.近年来国内外报道了Ⅰ型鸭肝炎病毒的变异株,且已完成了病毒基因组的测序工作,并随之出现RT-PCR诊断技术,对雏鸭病毒性肝炎的诊断和防控具有重要意义.     

美国大流域长时间序列水土保持减沙效果分析

 为借鉴美国开发治理比较早的一些河流的经验教训,选择密苏里河上游的Willow、佐治亚州LloydShoals水库、韦科、田纳西河一级支流渡科河、科罗拉多河上游等5条较大的流域进行水土保持减沙效果分析。通过前后长达1032年的大流域、长时间序列的水土流失治理,在排除降雨和水利工程影响的因素,其下游河道减沙效果都很显著,减沙分别在38%～55%之间。     

绿色荧光蛋白基因与猪瘟兔化弱毒疫苗株E2基因在杆状病毒中的融合表达

为了研究猪瘟病毒E2糖蛋白的立体结构及生物学特性，将增强型荧光蛋白基因（EGFP）和猪瘟兔化弱毒疫苗株（HCI.V）E2基因经PCR扩增后克隆至pBlueBacHis2A质粒，与杆状病毒DNA共转染后经PCR鉴定获得了含有EGFP和HCLVE2融合基因（GFPTE2）的重组杆状病毒rBACTE2-339，并将其感染sf9细胞后在荧光显微镜下观察到了亮绿色荧光．说明融合基因已初步表达。