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91.
将已经通过体外验证能够有效抑制山羊痘病毒复制的shRNA转入山羊体细胞,构建其表达细胞系.将已经通过验证能够靶向抑制山羊痘病毒ORF095基因并有效抑制GTPV的pGPU6/GFP-ORF095-siRNA-70转染山羊原代成纤维细胞,经800μg/mL G418抗性筛选7~8d后,用含200μg/mL G418和10~15ng/mL EGF的培养基进一步单克隆化并将单克隆细胞扩大、传代培养,应用RT-PCR检测及测序鉴定所构建的细胞系.结果表明:本试验获得的1株成纤维细胞系基因组含有ORF095-siRNA-70表达框架,为进一步进行体细胞克隆转基因动物的制备和RNAi体内抗山羊痘病毒的研究奠定了基础. 相似文献
92.
【目的】分离流行于我国南方地区的流行性出血病病毒血清6型毒株(EHDV-6),掌握分离毒株的遗传特征。【方法】对设立于我国云南和广东省的哨兵动物定期采血,进行EHDV感染情况监测与病毒分离培养。通过血清中和试验确定分离EHDV的血清型,采用一步法RT-PCR对分离的EHDV-6毒株基因节段2、3、6(Seg-2、-3、-6)进行扩增与序列分析。【结果】2012—2016年,从云南省和广东省的哨兵动物中分离出25株EHDV毒株,其中,11株为EHDV-6型。中国EHDV-6型毒株的Seg-2、-3与-6均属Eastern型,核酸序列相似性分别为99.1%、98.9%和98.8%,在系统发生树上分别聚为1个独立的中国支系。在日本引起疫病暴发的EHDV-6型毒株与中国EHDV-6型毒株具有最近的亲缘关系。日本EHDV-6型毒株在系统发生树上处于中国支系内部,Seg-2、Seg-3与中国毒株的核酸序列相似性分别为98.5%和93.9%。【结论】云南和广东省流行的EHDV-6型毒株核酸与氨基酸序列高度相似;日本和中国的EHDV-6型毒株具有最近的亲缘关系,提示中日之间可能存在EHDV的流动。研究结果为进一步开展我国EHDV-6型毒株流行病学分析、致病性、病原学诊断与疫苗制备等研究提供了基础。 相似文献
93.
GUAN Rong-xia GUO Xiao-li LIU Dong-cheng CAO Shuang-He ZHANG Ai-min 《中国农业科学(英文版)》2002,1(10):1089-1093
Inter-simple sequence repeat (ISSR) analysis was carried out on a F2 population of 147 plants derived from a cross between a wheat male fertility restorer line 2114 and a male sterile line ND44A. Out of 43 primers examined, 18 primers produced distinguishable, polymorphic bands between the two parents. Linkage analysis in the mapping population showed that two markers UBC-808 and UBC-848 were closely linked with the restorer gene R f6 of the Triticum timopheevii CMS system. The distance between the two markers and the restorer gene was 7.9 cM and 4.9 cM, respectively. Also two parents were screened with 181 pairs of SSR primers, of which, 34.3% showed polymorphisms. But no locus was found linked with the restorer gene.Compared with the SSR technique, the ISSR approach used in the experiment provided more information and proved to be a valuable method to identify alien fragments. 相似文献
94.
不同形态氮素及ABA和6-BA对烟草生长、养分吸收及其在体内分配的影响 总被引:8,自引:0,他引:8
研究表明,铵态氮抑制植物生长可能与植物体内源激素水平的变化有关。为证实不同形态氮在植物体内的作用,通过结合使用植物激素脱落酸(ABA)及6-苄基腺嘌呤(6-BA),研究了NH4^ -N和NO3^--N对烟草生长、叶片蒸腾、养分吸收及在体内分配的影响。与供应NO3^--N不仅抑制了植物生长、阳离子吸收,而且抑制了植物的蒸腾,表明NH4^ -N处理导致至少部分气孔关闭。供应NO3^--N条件下,用ABA喷施叶片也能降低叶片蒸腾,但对烟株生长及养分吸收基本没有影响。6-BA不能明显缓解NH4^ -N对植物生长的抑制作用。 相似文献
95.
Renhui Zhao Bingliang Liu Zhengning Jiang Tiantian Chen Ling Wang Yaoyong Ji Zhubing Hu Huagang He Tongde Bie 《Plant Breeding》2019,138(5):503-512
Wheat‐Dasypyrum villosum translocations T6V#2S·6AL and T6V#4S·6DL, carriers of Pm21 and PmV, respectively, confer high resistance to wheat powdery mildew. For better understanding of the difference in genetic effect between them, a RIL population was constructed based on the cross between “Yangmai 18” carrying T6V#2S·6AL and “Yangmai 22” carrying T6V#4S·6DL. Analysis of distribution of the translocations showed that T6V#2S·6AL is much more transmittable than T6V#4S·6DL. By comparing their effects on main agronomic traits, we firstly found that T6V#2S·6AL contributes greatly to top spikelet fecundity, but causes a decrease of 6.7%–10.5% of spike number. No stable effects of T6V#4S·6DL on agronomic traits were found, except for positive effect on plant height. Excitingly, a new recombinant, T6V#4S‐6V#2S·6AL carrying PmV, was screened and proved to have a higher transmission rate than the original translocation T6V#4S·6DL, which will greatly promote the utilization of PmV. The above conclusions of this research will provide important guidance for utilization of Pm21 and PmV more effectively, in wheat powdery mildew resistance breeding. 相似文献
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98.
巴丰6号是内蒙古巴彦淖尔市农业科学院选育的中熟、多穗、丰产、优质型小麦品种。该文从农艺性状、产量、品质、抗逆性等方面对该品种的品种特征特性进行了介绍,并分析了该品种的综合利用前景。 相似文献
99.
J.A. Lucas B. Ramos Solano F. Montes J. Ojeda M. Megias F.J. Gutierrez Mañero 《Field Crops Research》2009
Biocontrol capacity of two plant growth-promoting rhizobacteria (PGPR) strains, against blast disease in rice paddy fields in Southern Spain was studied in three cropping seasons. Both strains (Pseudomonas fluorescens Aur 6 and Chryseobacterium balustinum Aur 9) had already shown biocontrol capacity against pathogens, ability to induce systemic resistance against leaf pathogens and against salt stress in different plant species. Bacterial treatments were carried out on seeds and/or on leaves. Strains were inoculated individually and in combination. Protection against natural disease incidence was evaluated, and rice production and quality measured in 2005 and 2006 trials. In 2004, natural disease incidence was low (between 0.1% and 0.35% of damaged leaf surface) due to environmental conditions; under these conditions, both strains significantly protected plants against rice blast. In 2005, disease incidence was higher than in 2004, reaching higher values of affected leaf surface in controls. In these conditions, each strain individually protected rice against rice blast, although the combination of both strains was the most effective treatment. All three treatments (Aur 6, Aur 9 and Aur 6 + Aur 9) reached 50% protection in panicles, with Aur 9 being the most effective. In 2006, the most effective treatment was the combination of both strains on leaves in three physiological stages, suggesting a biocontrol mediated protection. On the other hand, when bacteria were applied to seeds, disease incidence decreased up to 50%, suggesting induction of systemic resistance. Finally, a direct relation between protection mediated by the PGPR and the increase in rice productivity (mT/ha) and quality (weight of 1000 seeds and number of intact grains after milling) was found. 相似文献
100.
播量和施肥对甘啤6号产量和品质的影响 总被引:2,自引:0,他引:2
为筛选出河西地区啤酒大麦高产优质栽培的适宜播量和施肥组合,以当地啤酒大麦主栽品种甘啤6号为材料,采用正交设计,研究了播量、氮肥、磷肥对该品种产量、籽粒品质及麦芽品质的影响。结果表明,播量、氮肥、磷肥组合对大麦产量、籽粒品质和麦芽品质影响显著。就产量而言,最佳播量为525 万粒·hm-2,施氮最佳水平为180 kg·hm-2,P2O5最佳水平为90 kg·hm-2;对产量的影响表现为播量>氮肥>磷肥。播量在375万~525万粒·hm-2范围内,籽粒蛋白质含量随播量的增加而下降,但播量达到600万粒·hm-2时蛋白质含量又有所增加。籽粒蛋白质含量随着氮肥施用量的增加呈直线上升趋势,适量施磷可以在保证产量的同时,抑制蛋白质含量的增加;对蛋白含量的影响表现为氮肥>播量>磷肥,对千粒重的影响表现为播量>磷肥>氮肥。综合来看,在播量为525万粒·hm-2、施氮量为120 kg·hm-2、P2O5施用量为210 kg·hm-2条件下,甘啤6号具有较高的籽粒产量和较低的蛋白质含量,且千粒重、整齐度和主要麦芽品质均达国家优级水平,因此该处理可作为河西地区甘啤6号实现高产优质的适宜播量与施肥组合。 相似文献