瓜实蝇国内研究概况

瓜实蝇是一种世界性检疲害虫,在我国属二类检疫害虫,可危害100多种蔬菜和水果.综述了瓜实蝇在我国的研究现状,包括瓜实蝇的分布、寄主、危害程度、分类鉴定、生物学、生态学、生理生化、经济重要性评价、综合防治等,并对瓜实蝇的综合防治进行了展望.     

Improved methods for quantifying potential nutrient interception by riparian buffers

Efforts to quantify the effects of riparian buffers on watershed nutrient discharges have been confounded by a commonly used analysis, which estimates buffer potential as the percentage of forest or wetland within a fixed distance of streams. Effective landscape metrics must instead be developed based on a clear conceptual model and quantified at the appropriate spatial scale. We develop new metrics for riparian buffers in two stages of increasing functional specificity to ask: (1) Which riparian metrics are more distinct from measures of whole watershed land cover? (2) Do functional riparian metrics provide different information than fixed-distance metrics? (3) How do these patterns vary within and among different physiographic settings? Using publicly available geographic data, we studied 503 watersheds in four different physiographic provinces of the Chesapeake Bay Drainage. In addition to traditional fixed-distance measures, we calculated mean buffer width, gap frequency, and measures of variation in buffer width using both “unconstrained” metrics and “flow-path” metrics constrained by surface topography. There were distinct patterns of relationship between watershed and near-stream land cover in each physiographic province and strong correlations with watershed land cover confounded fixed-distance metrics. Flow-path metrics were more independent of watershed land cover than either fixed-distance or unconstrained measures, but both functional metrics provided greater detail, interpretability, and flexibility than the fixed-distance approach. Potential applications of the new metrics include exploring the potential for land cover patterns to influence water quality, accounting for buffers in statistical nutrient models, quantifying spatial patterns for process-based modeling, and targeting management actions such as buffer restoration.     

水杨酸对切花栀子生理效应的影响

研究了不同浓度水杨酸(SA)对栀子花插瓶期间的保鲜效应,测定了瓶插寿命、鲜重变化率、花朵直径、水分平衡值、开花级数等指标。结果表明:D配方(3%S+100mg/LSA)对栀子花的保鲜效果最好。     

无籽冰淇淋西瓜新品种的选育

无籽冰淇淋（454-S×HY1）是湖南省瓜类研究所最新育成的优质、抗病耐湿、黄瓤且具奶油味的中小果型特色无籽西瓜新品种。全生育期92d左右,果实发育期33d左右,易坐果,单瓜质量3.5~5kg,一般产量3000~3500kg/667m2,果实中心折光糖含量12%左右。2009年4月通过湖南省农作物品种审定委员会审定。     

六种兰属植物的核型分析

 利用染色体压片技术对五种兰属原生种和一种杂交种的染色体数和核型进行了研究。结果如下：多花兰（Cymbidium floribundum Lindl.）2n=2x=40=36m+4sm;冬凤兰（Cymbidium dayanum Rchb.f ）2n=2x=40=36m+4sm;硬叶兰（Cymbidium bicolor Lindl. subsp.obtusum Du Puy et Cribb）2n=2x=40=40m（4SAT）;美花兰（Cymbidium insigne Rolfe）2n=2x=40=2M+36m+2sm;独占春（Cymbidium eburneum Lindl.）2n=2x=40=32m+8sm;小金童（Cymbidium golden Elf.‘Sundust’）2n=2x=40=34m+6sm（2SAT）。并对其的亲缘关系及在兰花育种中的作用进行了讨论。     

保护地西瓜根际线虫种群调查

本文对保护地西瓜根际线虫进行了抽样调查.结果表明,西瓜根际线虫分属8科16个属.其中绝大部分为腐生类线虫,寄生类线虫较少;西瓜根际线虫的时空动态表现为随西瓜根系的生长发育而分布的现象[1];西瓜不同生育期线虫数量呈现先升后降的趋势,抽蔓期线虫数量最多,拔秧期线虫数量下降.降至低于幼苗期;西瓜根际线虫主要集中在10～30cm土层.0～10cm和30～40cm土层线虫数量明显减少.     

适于SSR-PCR的农作物基因组总DNA高通量提取方法的建立

[目的]建立一种新的、通用、快速的农作物基因组总DNA提取方法,为应用分子标记技术研究遗传多样性及变异提供方便.[方法]分别从甘蔗、水稻、玉米、花生和大豆5种作物中提取基因组DNA,用琼脂糖凝胶电泳对所提取的DNA质量进行检测,然后每种作物分别选取两对SSR引物进行PCR扩增,用聚丙烯酰胺凝胶电泳检测扩增结果.[结果]采用该提取方法,不同作物产生的纯DNA在100.0~160.0 g/g,提取DNA的A260/A280比率在1.80~1.95.此外,电泳凝胶未出现可见的RNA污染,每个作物基因组DNA单一条带非常清晰,DNA结构完整,质量较高,适用于分子标记的研究.应用SSR分子标记进行PCR扩增,重复性、稳定性好,经琼脂糖凝胶电泳检测,条带清晰且分辨率较高.[结论]建立的DNA提取方法为直接将叶片剪碎后装入EP管中,加入提取缓冲液进行DNA提取,省去了用液氮研磨的过程.与传统的DNA分离方法相比,新建立的DNA提取方法具有高通量、简单、快速、经济效益高等优点.     

Surveillance of amyloidosis and other diseases at necropsy in captive trumpeter swans (Cygnus buccinator).

The purpose of this study was to characterize the incidence and diagnostic features of amyloidosis and other diseases found at necropsy in captive trumpeter swans (Cygnus buccinator). A search of Iowa State University's Department of Veterinary Pathology and Veterinary Diagnostic Laboratory databases yielded 31 trumpeter swan (C. buccinator) necropsy cases from captive swans in protected habitats. Eleven of the 31 birds had amyloid deposition most commonly in the spleen (8 of 11), liver (7 of 11), and kidney (6 of 11) and less often in the pancreas (2 of 11) and adrenal gland (2 of 11). Amyloid deposition effaced normal tissue with adjacent necrosis and hemorrhage in severe cases. Amyloidosis was most often diagnosed in February and March. Other disease diagnoses in the trumpeter swans included aspergillosis (5 of 31, 16%); bacterial infection (5 of 31, 16%); lead toxicosis (3 of 31, 10%); gout (2 of 31, 6%); parasitic infection (2 of 31, 6%); vitamin E deficiency (1 of 31, 3%); trauma (1 of 31, 3%); and ventricular foreign body (1 of 31, 3%). Histopathologic, toxicologic, and microbiologic analyses did not define an etiologic diagnosis in the deaths of 9 trumpeter swans. In these cases, necropsy lesions included emaciation (5 of 9), enteritis (1 of 9), pulmonary hemorrhage (1 of 9), and no lesions (3 of 9). The number of trumpeter swan case submissions was greatest in January and February. This study provides a reference for veterinary diagnosticians concerning incidence and diagnostic features of amyloidosis and other diseases in captive trumpeter swans of the midwestern United States.