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991.
A total of 4,681 accessions of Hordeum vulgare landrace material from Ethiopia, East Mediterranean, Near East, Nepal and China
were sown in the field and subjected to the natural powdery mildew epidemic in Denmark. Apparently resistant accessions were
selected. Selfed progeny from them were retested and reselected in subsequent years at four locations in Denmark. Finally,
16 promising donors of resistance were retained. They were characterized in the field and tested in the seedling stage for
reaction to up to 72 different isolates of the powdery mildew fungus. The absence of the corresponding virulences in the Danish
airborne powdery mildew population was ascertained in five years. The resistances in the 16 donors are apparently mutually
different and from known sources of powdery mildew resistance in barley.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
992.
Based on the analysis of expert experience on generation system planning(GPS), the theory of knowledge based method is introduced into GPS to express the constraints of engineering(viz. Expert experience of engineering), and to discard abundant improper program during the earlier stage of GPS. In this situation, the difficulty degree of optimizing calculation in the later stage of GPS is lessened. And then, integrating expert system with production simulation in a method of GPS is proposed and is verified with an example. The results show that the method presented is effective. 相似文献
993.
On the basis of the character and feature interpretation of tomato disease,the prognosticate, prediction and diagnosis of tomato are researched. Thus,it may be widely applied in the developing research of the expert system about the prognosticate,prediction and diagnosis of tomato desease. 相似文献
994.
995.
The GIS function and technique characteristics are introduced. With Client/Server and Browser/Server structure, the paper developed the soil information system based on GIS by using MapInfo to manager spatial data and SQL Server attribute data. The system realizes the inquire, retrieve and statistical analysis of soil fertility and classify information. The function of thematic map making, output and renew are also supported. The system does good to make better use of soil information. 相似文献
996.
997.
998.
This paper aims at analysis on essence of urban public space from viewpoint of energy aggregation and puts forward the conception of potential energy field through the study on universal significance of energy exchange, reflection of important characteristics of energy exchange in urban public space form, static state and development about typical urban pubic space-street and square. Corresponding methods of urban design and conception of planning under the contemporary era are studied. 相似文献
999.
为了解北方白菜型冬油菜膜脂脂肪酸和ATPase活性与抗寒性的关系,以抗寒性强的冬油菜品种陇油7号和抗寒性弱的品种天油2号为材料,研究了不同温度处理(25°C、10°C、2°C、–5°C)后叶片和根系膜脂脂肪酸组分和ATPase酶活性的变化。结果表明,低温胁迫下2个冬油菜品种叶片和根系膜脂脂肪酸组分相同,叶片中不饱和脂肪酸以亚麻酸为主,根系不饱和脂肪酸以亚油酸为主。随处理温度的降低,2个冬油菜品种叶片不饱和脂肪酸含量呈先降低(10°C,2°C)后增加(–5°C)的趋势;陇油7号根中不饱和脂肪酸含量逐步增加,天油2号则逐步降低;在低温条件下(2°C,–5°C),陇油7号膜脂U/S比值、IUFA值高于天油2号;ATPase活性表现为陇油7号逐渐高于天油2号。说明2个冬油菜品种的膜脂在低温响应上存在一定差异,低温下不饱和脂肪酸含量和ATPase活性的提高是强抗寒冬油菜品种在北方旱寒区严酷环境条件下能安全越冬的重要原因。 相似文献
1000.
利用染色体片段代换系定位陆地棉株高QTL 总被引:4,自引:0,他引:4
以陆地棉中棉所36为轮回亲本和海岛棉海1为供体亲本, 构建染色体片段代换系。为了能检测到稳定的株高QTL,将三个代换系群体(BC5F3, BC5F3:4和BC5F3:5)在5个环境中种植,2009年和2010年分别在河南安阳种植BC5F3单株、BC5F3:4株行, 2011年分别在河南安阳、辽宁辽阳和新疆石河子种植BC5F3:4株系。结果表明,在不同群体环境中株高的超亲比例为53.43%~88.97%。从早期构建的总图距为5088.28 cM, 含有2280个SSR标记位点,覆盖26条染色体的遗传连锁图谱中筛选标记,对408个单株进行的SSR鉴定,结果检测到16个株高QTL,分布在10条染色体上。单个QTL解释的表型变异为7.35%~13.17%。有7个QTL在2个以上环境被检测到。与标记MUSS563紧密连锁的qPH-15-19在一个环境中被检测到,在前人的研究中也有报道。这些结果为进一步精细定位QTL、基因克隆、分子辅助选择等研究奠定基础。 相似文献