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991.
以张家口弘基牧业开发有限责任公司为典型案例,详细介绍了企业种植业与养殖业相结合,通过绿色循环经济促进蔬菜产销体系发展、提高经济效益、环境效益和社会效益的经营模式,说明了种植与养殖结合的产业经营模式对促进绿色有机蔬菜产业发展及保证食用安全的重要性。在此基础上,提出了以农村合作社为主体,实现和推广种植养殖结合发展绿色有机蔬菜产业模式的建议。 相似文献
992.
Summary The morphology of 12 pachytene bivalents of the dihaploid Solanum tuberosum cv. Gineke is described, and the morphological features which are helpful for a critical chromosome identification are illustrated. The difficulties of identifying the individual chromosomes and the extra chromosomes in trisomics are discussed. 相似文献
993.
黄瓜的分子标记和连锁图谱研究进展 总被引:4,自引:0,他引:4
黄瓜分子标记和遗传连锁图谱的研究工作相对番茄、小麦等作物比较落后,至今开展的分子标记研究多围绕黄瓜遗传关系分析进行,现有的几张遗传连锁图谱基本是由美国Staub研究小组完成,已被定位在图谱上的同工酶、RAPD、RFLP、SSR、AFLP等标记总数达到300多个,各标记间平均距离达到2.1cM,被整合在一起的遗传基因不足10个(F、B、de、ll、dm)。 相似文献
994.
Before the gap enlarging among the areas in the western region, and on the basis of the theory and model of development pole, this paper studies the way of optimizing of industry structure of Chongqing in order to accelerate the rate of progress of the development of the western region, and to advance its economy power during it. By indexing the system's construction and analysing the demonstration, we consider that the instrument manufacturing sector, building, transport equipment manufacturing, general machinery, finance and insurance, and service industry of IT should be cultivated and supported as the cut-in industries in Chongqing. 相似文献
995.
A sequence-specific PCR marker linked with Pm21 distinguishes chromosomes 6AS, 6BS, 6DS of Triticum aestivum and 6VS of Haynaldia villosa 总被引:4,自引:0,他引:4
To develop markers linked with Pm21 located on chromosome 6VS of Haynaldia villosa, a pair of primers (NAU/xibao15F and NAU/xibao15R) were designed according to the sequence of a serine/threonine kinase gene (Contig17515), whose expression was induced by Blumeria graminis and selected from the gene expression experiment using the Barley GeneChip. Using genomic DNA of various genetic stocks including the wheat variety ‘Yangmai#5’, H. villosa, Triticum durum–H. villosa amphiploid, seven T. aestivum–H. villosa addition lines involving chromosomes 1V–7V, the translocation line T6VS·6AL, and 21 nullisomic–tetrasomic and eight deletion lines of T. aestivum‘Chinese Spring’ as templates, four amplicons specific for 6VS, 6AS, 6BS and 6DS, respectively, were produced. F2 individuals derived from the cross of ‘Yangmai#5’ × T6VS·6AL were analysed, and data indicate that NAU/xibao15902 could be used as a co‐dominant marker for selecting Pm21 located on 6VS. 相似文献
996.
M. L. Warburton J. M. Ribaut J. Franco J. Crossa P. Dubreuil F. J. Betrán 《Euphytica》2005,142(1-2):97-106
Characterization of genetic diversity among maize inbred lines can facilitate organization of germplasm and improve efficiency of breeding programs. A set of 218 phenotypically diverse inbred maize lines developed at CIMMYT for hybrid production was characterized using 32 RFLP markers to: (1) analyze the genetic diversity present; (2) define potential heterotic groups based on clusters formed with marker data; and (3) identify the most representative testers for each potential heterotic group. Lines were clustered using five different genetic distance measurements to find consensus non-hierarchical clusters. Dendrograms were produced to study hierarchical classification within smaller groups of lines. A very high average allelic diversity was seen in this germplasm. Lines did not cluster based on phenotype, environmental adaptation, grain color or type, maturity, or heterotic response (as determined based on hybrid performance with testers), but lines related by pedigree usually did cluster together. Previously defined testers from opposite heterotic groups were not genetically differentiated, and did not represent well their heterotic group. Discrete clusters were difficult to find; thus, potential heterotic groups will be difficult to suggest using RFLP markers alone. However, suggestions on how to use molecular markers and cross performance information to refine heterotic groups and select representative testers are presented. 相似文献
997.
Summary In two experiments, using different testing methods, the number of newly formed cysts was determined on nine potato genotypes with resistance from various sources. Ten potato cyst nematode (PCN) populations were used in these experiments. Rank correlation between numbers of cysts over potato genotype-PCN population combinations for both experiments was high (rs = 0.90). Dendrograms for PCN populations and potato genotypes were constructed, based on a simultaneous hierarchical clustering procedure for potato genotype-PCN population interaction terms. Several virulence groups could be identified within Globodera rostochiensis as well as within G. pallida. Host genotypes, derived from the same sources of resistance, were clustered in different resistance groups. 相似文献
998.
999.
用初等方法证明了G≌A5当且仅当πe(G)={1,p,q,r},其中G是有限群,p,q,r是互不相同的素数. 相似文献
1000.
高原鼢鼠的采食造丘活动影响草地植被群落组成和结构,造成草地植被的空间异质性——土丘和植被斑块。本研究以冬季牧场中不同高原鼢鼠种群密度干扰下的植被性状为研究对象,探索植被群落组成结构对高原鼢鼠不同种群密度干扰的功能性响应。结果表明:植被高度随着鼢鼠种群密度的增加呈显著增加趋势(P<0.05),群落盖度和禾草丰富度呈显著下降趋势(P<0.05),而物种丰富度及杂类草丰富度随鼢鼠种群密度的增加表现出单峰曲线格局。地下总生物量随鼢鼠种群密度的增加呈显著下降趋势(P<0.05),杂类草生物量则表现出相反的趋势,而禾草类生物量表现出先降低后增加的趋势。由此可见,适宜密度的鼢鼠干扰有利于物种丰富度的提高,而低密度和高密度的鼢鼠干扰有利于草地中禾草生物量的提高。 相似文献