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41.
《国际木业》:上海红虹木业有限公司作为一家拥有悠久历史的家族企业,自从事木材行业至今已发展为在北美、欧洲、东南亚等地区都有力量分布的规模供应商,整个过程中企业对自己的理念和战略有怎样的发展? 相似文献
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利用雄性不育选育辣椒新品种农大082 总被引:1,自引:0,他引:1
农大082是以雄性不育系S200243A为母本,恢复系S200244C为父本配制而成的微辣型辣椒一代杂种。中早熟,从定植到始收30d(天)左右,果实羊角形,果纵径17—20cm,横径3-4cm,嫩果深绿色,成熟果红色,味微辣,果肉脆嫩,平均单果质量40—60g,667m^2产量3200-4600kg,抗TMV,耐CMV。已在北京、河北、四川、黑龙江等地示范推广逾400hm^2。 相似文献
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山西省蚜虫消长与玉米矮花叶病流行关系 总被引:4,自引:0,他引:4
玉米矮花叶病是非持久性病毒——MDMV 引起。病毒介体是蚜虫,在山西省主要是麦二叉蚜(Schizaphis graminum Rond)、禾缢管蚜(Rhopalo-siphum padi Linnaeus)、玉米蚜(Rhopalosiphum maidis Fitch)、桃蚜(Myzus persicae Sulzer)和棉蚜(Aphis gossypii Glover),麦无网长管蚜[Acythosiphum dirhodum(Walker)]的传毒能力未定。实验表明,传毒蚜虫饲毒最适时间5~30分钟,接毒最适时间30~60分钟,持毒期限6~7小时,有效传毒蚜数3~5头。气温20℃麦二叉蚜的传毒效能最高,是春播玉米的主要传毒蚜虫。传毒蚜的高峰期后16~30天是发病高峰,以玉米拔节至孕穗间发病最快,抽雄后渐缓。病害的发生流行取决于毒源量、传毒蚜的虫口密度及其自然带毒率的提高,这过程进展的快慢是受时间和空间的影响。 相似文献
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A. Schots J. De Boer A. Schouten J. Roosien J. F. Zil Verentant H. Pomp L. Bouwman-Smits H. Overmars F. J. Gommers B. Visser W. J. Stiekema J. Bakker 《European journal of plant pathology / European Foundation for Plant Pathology》1992,98(2):183-191
Engineering resistance against various diseases and pests is hampered by the lack of suitable genes. To overcome this problem we started a research program aimed at obtaining resistance by transfecting plants with genes encoding monoclonal antibodies against pathogen specific proteins. The idea is that monoclonal antibodies will inhibit the biological activity of molecules that are essential for the pathogenesis. Potato cyst nematodes are chosen as a model and it is thought that monoclonal antibodies are able to block the function of the saliva proteins of this parasite. These proteins are, among others, responsible for the induction of multinucleate transfer cells upon which the nematode feeds. It is well documented that the ability of antibodies to bind molecules is sufficient to inactivate the function of an antigen and in view of the potential of animals to synthesize antibodies to almost any molecular structure, this strategy should be feasible for a wide range of diseases and pests.Antibodies have several desirable features with regard to protein engineering. The antibody (IgG) is a Y-shaped molecule, in which the domains forming the tips of the arms bind to antigen and those forming the stem are responsible for triggering effector functions (Fc fragments) that eliminate the antigen from the animal. Domains carrying the antigen-binding loops (Fv and Fab fragments) can be used separately from the Fc fragments without loss of affinity. The antigen-binding domains can also be endowed with new properties by fusing them to toxins or enzymes. Antibody engineering is also facilitated by the Polymerase Chain Reaction (PCR). A systematic comparison of the nucleotide sequence of more than 100 antibodies revealed that not only the 3′-ends, but also the 5′-ends of the antibody genes are relatively conserved. We were able to design a small set of primers with restriction sites for forced cloning, which allowed the amplification of genes encoding antibodies specific for the saliva proteins ofGlobodera rostochiensis. Complete heavy and light chain genes as well as single chain Fv fragments (scFv), in which the variable parts of the light (VL) and heavy chain (VH) are linked by a peptide, will be transferred to potato plants. A major challenge will be to establish a correct expression of the antibody genes with regard to three dimensional folding, assembly and intracellular location. 相似文献
47.
早生桑品种育151、育237的育成 总被引:1,自引:1,他引:0
采用杂交方法育成早生桑品种育151、育237,具有发芽早、产叶量高,叶质较优、抗黄化型萎缩病较强等特性,发芽期比早青桑捉早2-3天.比湖桑32号早8天左右.产叶量提高6-41%. 相似文献
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Shohei MATSUURA Shigeru HOSHINO Hideaki HAYASHI Tetsuyuki KOHGUCHI Kyoji HAGIWARA Toshihiro OMURA 《Journal of General Plant Pathology》2002,68(1):99-102
DAS-ELISA proved to be reliable enough to detect a latent infection by Tomato spotted wilt virus (TSWV) in asymptomatic stock plants of chrysanthemum. A high density of Frankliniella occidentalis, the predominant vector, in the presence of latently infected stock plants resulted in a high incidence of disease in the chrysanthemum
production field. The incidence of disease was low when the vector thrips were not abundant in spite of the presence of latently
infected stock plants. These results suggest that an infestation of the vector thrips causes severe secondary spread of TSWV
originating from latently infected stock plants in chrysanthemum production fields.
Received 27 July 2001/ Accepted in revised form 27 November 2001 相似文献