不同种源山杏光合生理特性日进程研究

以12个种源的山杏为试材,采用LI-6400便携式光合作用测定仪,在自然条件下对内蒙古林木良种繁育中心,对山杏种质资源库中的12个种源的山杏光合速率日进程变化进行了测定研究,进而研究了其光合日进程变化特征和对该区环境的适应性。结果表明:各种源光合速率、气孔导度和蒸腾速率日变化都具有单峰、双峰和多峰3种类型,第1峰一般出现在10:00—12:00。除凉城种源外东部区各种源光合速率日均值都大于西部区各种源,科左后旗最大(4.772 5μmol·m~(-2)·s~(-1)),而气孔导度和蒸腾速率日均值没有东部和西部种源的差异。万家沟种源光合速率、气孔导度和蒸腾速率日均值都低于其它种源,分别为1.665 5、0.041 5、0.817 8mmol·m~(-2)·s~(-1)。依据水分利用效率大小12个种源可分为3类:水分利用效率较高的种源有克什克腾旗、科左后旗、阿鲁科尔沁;其次为扎鲁特旗、科右中旗、扎赉特旗、巴林右旗、乌兰浩特,较小的为乌拉山、凉城、敖汉、万家沟。克什克腾旗最大(4.180 7mmol/mol),万家沟最小(1.893 5mmol/mol)。根据光合能力、水分消耗和水分利用效率综合分析指出,在呼和浩特地区推广栽植的山杏种源首选克什克腾旗种源,其次为科左后旗和阿鲁科尔沁种源,其光合能力大、水分消耗小,能适应该区干旱气候条件,为该区山杏引种选育和栽培提供理论依据。     

Immunogenicity and haemagglutination of recombinant Avibacterium paragallinarum HagA

Inactivated vaccines of Avibacterium paragallinarum provide protection and reduce the economic losses caused by infectious coryza. However, inactivated bacterins provide protection only against the Page serovars included in the vaccine. In this study, we investigated the immunological properties of a functional recombinant haemagglutinin protein (rHagA) derived from a Taiwan isolate strain A9 as the immunogen for vaccination. The rHagA subunit vaccine protected 71% of immunized chickens against 10(10) colony-forming units (CFU) of viable A9. Vaccinated chickens which showed no clinical signs of coryza developed haemagglutination inhibition (HI) titers of 1:10 or greater. Haemagglutination (HA) of serovars A and C was not affected by the presence of rHagA specific antiserum. The HA of rHagA could only be induced against formaldehyde-fixed chicken red blood cells (FA-RBCs). These results suggested that HagA is a moderate immunogen and might not be a major haemagglutinin in vivo. However, HagA might be involved in haemagglutination when treated serovar C aggregates fixed RBCs in vitro.     

收获期对玉米茎秸产量和营养价值的影响

研究适于云南亚热带地区的玉米品种.结果表明:玉米青秸产量以蜡熟期最高,干秸产量以完熟期最高;粗蛋白质产量和产奶净能量(NEL)均以蜡熟期最高;专用青贮玉米、粮饲玉米和普通玉米蜡熟期鲜秸产量分别为108.9、111.7和127.5 t/hm2,干秸产量为33.4、36.4和40.7 t/hm2,粗蛋白质产量为2.7、2.9和3.4 t/hm2,产奶净能量为49825.8、57789.4和64430.3 Mcal/t/hm2;高产优质玉米品种为京科9号、樱红和路单4号.     

浮床种植草坪草对富营养化水体的净化作用研究

采用浮床种植草坪草技术,研究了高羊茅Festuca arundinacea、匍匐翦股颖Agrostis stolonifera 2种草坪草对富营养化水体的净化能力.试验结果表明,2种草坪草对富营养化水体中的氮(N)、磷(P)、化学需氧量(CODcr)等具有明显的净化效果,尤其对总磷(TP)的净化能力最强,能有效改善富营养化水体的水质;2种草坪草之间,匍匐翦股颖对TP的去除效果显著高于高羊茅对TP的去除效果.研究结果显示浮床种植草坪草技术可能是一条有效的修复富营养化水域的新途径.     

葡萄VvSUC12基因启动子的克隆及上游调控因子鉴定

枝干病害葡萄溃疡病近年来严重限制了葡萄产业发展。研究表明葡萄蔗糖转运蛋白参与寄主植物和病原菌的互作过程。为解析蔗糖转运蛋白VvSUC12在葡萄免疫反应过程中的功能,本研究克隆了VvSUC12基因翻译起始位点上游1 500 bp的启动子区,通过生物信息学分析发现该区域包含4个Dof转录因子结合序列(A/TAAAG)及多种激素调节与防御相关的顺式元件。实时荧光定量分析显示,接种可可毛色二孢菌显著诱导VvSUC12和VvDof19基因的表达。通过酵母单杂交实验筛选得到与VvSUC12启动子互作的转录因子VvDof19。酵母双杂交实验证实VvDof19具有自激活活性;进一步通过烟草瞬时表达发现Dof19-GFP的相对GUS活性约为对照GFP的9倍,表明转录因子VvDof19能够激活VvSUC12基因的表达。研究结果为深入研究蔗糖转运蛋白在葡萄免疫反应中的功能奠定基础。     

农牧交错带灌溉和旱作模式下马铃薯耗水差异

为揭示北方农牧交错带地区马铃薯“水改旱”种植对其产量和水分利用的影响,选取中国北方农牧交错带地区27个站点,基于站点的气象数据、土壤数据和管理数据驱动充分验证的APSIM-Potato模型,模拟分析农牧交错带地区灌溉和雨养马铃薯的耗水差异。结果表明：北方农牧交错带地区马铃薯种植连续灌溉10、20 a和30 a的产量分别为15 900～35 600、16 400～34 800 kg·hm^-2和16 600～34 800 kg·hm^-2,改为旱作后对应的产量分别为12 800～30 600、13 900～29 100 kg·hm^-2和12 700～25 500 kg·hm^-2;灌溉马铃薯产量均表现为西部较高,旱作马铃薯产量则为东部较高。连续灌溉10、20 a和30 a的播前1 m土层土壤含水量分别为163～388、161～394 mm和154～398 mm,改为旱作后分别下降31.8%、35.3%和36.9%。连续灌溉10、20 a和30 a后的地下水消耗量分别为5 360～21 330、8 910～4...     

野生老芒麦种质资源鉴定与基部叶鞘绒毛变异分析

为更好地利用老芒麦(Elymus sibiricus L.)野生资源,本研究从我国青藏高原、西北、华北、东北地区以及国外部分地区共采集了1 723份野生披碱草属种质资源,通过表型特征观测和流式细胞仪检测,共鉴定出了990份野生老芒麦种质,246份垂穗披碱草种质,并测得老芒麦的DNA含量在5.86～7.30 Gb之间,平均DNA含量为6.66 Gb;垂穗披碱草材料的DNA含量在9.50～10.36 Gb之间,平均DNA含量为9.97 Gb。研究结果显示,在西北、华北以及东北地区的部分野生老芒麦材料在苗期基部叶鞘出现了绒毛,分析发现该表型出现的概率与经度和纬度呈极显著正相关关系(P<0.01),与海拔、年年均气温以及年平均降雨量呈极显著负相关关系(P<0.01)。表明老芒麦苗期基部叶鞘绒毛的有无与环境因子之间存在着必然的联系,可能是老芒麦种质应对不同环境类型的适应性机制之一。本研究为老芒麦的形态鉴定提供了新的依据,为老芒麦种质资源挖掘和育种应用提供了材料基础。     

Intra- and interobserver assessments of intestinal wall thickness and segmentations from transverse sections of feline abdominal ultrasound images

Measurements of intestinal wall thicknesses from ultrasound imaging (US) are routinely used to support diagnoses of intestinal disorders in cats, however published studies describing observer agreement are currently lacking. The aim of this retrospective, observer agreement study was to quantify inter- and intraobserver repeatability and agreement in the measurement of intestinal wall layer thicknesses and the segmentation of transverse sections of small intestines in US images of 20 cats. Intestinal wall layer thickness measurements of the mucosa, submucosa, muscularis, serosa layer, and total thickness of these layers were performed on five cats with small cell epitheliotropic lymphoma, five with inflammatory bowel disease, and 10 with other conditions. Thickness measurements and the segmentation encompassing the serosa layer were obtained from five observers four times non-sequentially. The average standard deviation in thickness measurements (95% confidence interval) in the mucosa, submucosa, muscularis, serosa, and total thickness were 0.35 (0.07–0.95), 0.24 (0.07-0.52), 0.22 (0.06-0.49), 0.20 (0.05-0.49), and 0.57 (0.11-1.60) mm, respectively. The average intraclass correlation coefficients, which estimates the degree of consistency in thickness measurements and segmentation areas for each observer, ranged from 0.355 to 0.870 and 0.850 to 0.993, respectively. The interclass correlation coefficient, which estimates the degree of consistency when measuring a thickness or segmentation area over all observers ranged from 0.115 to 0.753, and 0.811 to 0.902, respectively. The overall average Dice Coefficient, which estimates the extent of overlap of the segmentations for all observers was 0.957 (0.933 to 0.972). Our results suggest segmentations of small intestines have a higher interobserver agreement than measurements of intestinal wall thicknesses.     

植物对磷饥饿的反应研究进展

磷是构成生命的重要元素之一,也是土壤中有效性最低的一种营养元素。我国是世界上最大的小麦生产国。但是我国耕地中有59%的土壤缺磷。农作物的产量常受到缺磷的影响而受损。土壤缺磷并不是土壤中总磷量低,而是土壤中可供植物直接吸收利用的有效态磷含量低。植物在磷饥饿时会发生各种各样的变化,以尽最大可能满足自身对磷的需求。植物对缺磷的反应是一个复杂的网络过程。大约有100多个基因参与了植物对缺磷的反应。其中主要的有磷转运蛋白基因、核糖核酸酶基因、磷酸酶基因等。植物在吸收外界的磷的过程中磷转运蛋白发挥了重要作用。植物磷转运蛋白基因按照序列相似性可以划分为H+/Pi共转运家族(Pht1家族)和Na+/Pi共转运家族(Pht2家族)。按照吸收动力学的标准可以分为高亲和力磷转运蛋白和低亲和力磷转运蛋白两种。磷饥饿时植物对磷吸收能力的增强的原因之一是增加了磷转运蛋白分子的合成数目。目前尽管人们对植物吸收磷的理解已经有了长足的进步,但是在植物对磷的具体调控机制、磷的跨液泡膜运输等重要方面仍然没有明确的结果。     

Fault Section Diagnosis Algorithm of Distribution Networks Based On Topology Identification

An algorithm of fault section diagnosis based on topology identification for distribution networks is presented. By decomposing the topologic matrix which describing the distribution network into two parts,one part only contain the complex coupling factor ,and the other ignore the complex coupling factor. Using this method, the fault zones in distribution network can be identified and isolated efficiently, and the vertexes of the zones can also be identified automatically. This approach adapts to the changefully network structures.