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野生稻与栽培稻体细胞杂交第4代特性研究初报 总被引：1，自引：0，他引：1
通过对D3代体细胞杂交后代进行白叶枯病检测,获得67份高抗白叶枯病体细胞杂交材料,并对D4代体细胞杂交材料人工白叶枯病接种和稻瘟病重发病区的田间自然诱发发病及大田种植结果分析.结果表明有86.6%的植株表现为抗白叶枯病,有16个株系较抗稻瘟病,有5个株系还存在分离现象,分离率为7.5%,有10个株系丰产性较好. 相似文献
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为了检验狐米草低能重离子各诱变株系在表型、生物量和内部生理生化状态发生变化的同时,其遗传物质DNA是否发生改变,试验检测了狐米草对照株系与各诱变株系的ITS序列.结果发现,所检测的狐米草10个诱变株系的ITS序列与对照株系完全一致,仅与美国德克萨斯州和路易斯安那州的狐米草株系差别1-2个碱基,显示低能重离子束诱变并没有导致狐米草株系在ITS区段发生变异. 相似文献
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叶盘共培养法介导的基因转移与两种转基因植物的鉴定 总被引：3，自引：0，他引：3
本文以共整合型Ti质粒载体pGV3850:1103neo中pNOS-NPTⅡ(Km~R)嵌合基因为遗传标志,应用改良的叶盘共培养法对烟草和番茄进行了遗传转化。通过施加选择压力,筛选出具有Km~R表型的愈伤组织,并由此获得转基因烟草和番茄植株。通过胭脂碱的高压电泳检测和生物素探针的尼龙膜印迹杂交,分别从侧面(间接)和正面(直接)证实了Km~R基因在上述两种转化细胞中的整合和表达。还探讨了转化、培养和筛选过程中的一些细节,并对改进技术的原理及其效果进行了讨论。 相似文献
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从83个菌株中筛选出瓜类炭疽病菌弱致病株系C3、C5分别用其活体接种和其灭活物浇根,成功诱导了两瓜对疽病菌强致病株系C2的抗病性,并证明了弱致病株系的灭活物与其活体本身具有相近的诱导能力,同时试蛉得出了C2灭活物诱导抗性的持续期和诱导处理的最佳间隔期． 相似文献
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野生稻与栽培稻体细胞杂交第4代特性研究初报 总被引：1，自引：0，他引：1
通过对D3代体细胞杂交后代进行白叶枯病检测，获得67份高抗白叶枯病体细胞杂交材料，并对D4代体细胞杂交材料人工白叶枯病接种和稻瘟病重发病区的田间自然诱发病及大田种植结果分析。结果表明有86．6％的植标表现为抗白叶枯病，有16个株系较抗稻瘟病，有5个株系还存在分离现象，分离率为7．5％，有10个株系丰产性较好。 相似文献
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从峨眉山采集健康的一把伞南星(Arisaema erubescens(Wall)Schott)植株,采用稀释涂布平板法从植物的组织液中分离内生细菌,采用牛津杯法筛选对大肠杆菌(Escherichia coli)有拮抗作用的抗性菌株。研究结果表明,从一把伞南星中分离得到内生细菌23株,经过初筛和复筛共得到2株对大肠杆菌有较强抑菌活性的内生细菌:YC06、YC09,这两个菌株的发酵产物对大肠杆菌也有抑菌作用,抑菌圈直径均在13.0 mm以上。 相似文献
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云南优质白肋烟配套技术研究 总被引：4，自引：5，他引：4
从引进品种中筛选出产质兼优、抗病性强、适合云南生态区种植的优良品种TN86．围绕调碱增香提高白肋烟质量目标，开展栽培、晾制技术研究，总结出云南优质白肋烟生产技术规范，生产示范，田间长势整齐清秀，晾制颜色均匀，烟碱量适宜，成份比例协调，内外在质量明显提高．杂交育种先后组配组合66个，优中选优，选出F2单株材料35个、F6单株或株系材料29个、遗传性状稳定株系25个，优良品系11个，为白肋烟新品种的继续筛选及配套技术在生产上的推广应用奠定了基础． 相似文献
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抗CMV病毒外壳蛋白CP基因导入黄瓜的研究 总被引：3，自引：0，他引：3
将CMV-CP基因经农杆菌感染介导转化黄瓜子叶,将CMV-CP基因导入黄瓜细胞,在含有卡那霉素和羧卡青霉素的MS培养基上诱导子叶分化,获得一批转化处理的黄瓜再生苗,分化率为23%左右,转基因黄瓜试管苗移栽在蔬菜种植土沙有机质为541的混合土中,其移栽成活率可达56%;委托省农科院品种引进中心进行转基因黄瓜再生植株对CMV的抗性接种试验结果表明7号株系为高抗,2、4号株系为中抗. 相似文献
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从皖北不同地区采集土壤样品,利用宿主结瘤法获得大豆根瘤,并采用平板划线法分离不同地区大豆根瘤菌株,共31株,对其进行染料及化学药物抗性、耐酸碱性、生长温度范围、耐盐性、抗生素抗性等性状的研究。结果表明,从31个菌株中筛选出总体抗性水平最为突出的菌株AWCS 13-4,其表现抗染料及化学药物能力最强;在pH4-pH12条件下生长良好,具有较广的酸碱度适应范围;在50℃条件下,仍可以缓慢生长;在6.0%NaCl处理下仍能生长,显示出很强的耐盐能力;并且在供试5种抗生素的不同浓度条件下均生长良好,表现出极强耐抗生素的能力。 相似文献
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以新鲜桑葚浆果作为酵母菌的分离源,从桑葚自然发酵过程中分离酵母菌,进而对所选菌株进行两级筛选.经过初步分离共得到了50株酵母,进一步TTC染色分离,共得到可产酒精的酵母28株,其中发酵前期14株,发酵中期8株,发酵后期6株. 相似文献
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《海外英语》2007,(5):10-11
Many college freshmen arrive woefully unprepared to do college work, and as disadvantaged populations continue to grow, the share of the American work force that has made it through college is expected to plummet. Many experts blame that educational failure not just on high schools but also on colleges. School & College, a special report by The Chronicle, looks at efforts to fix the system. What reforms would better prepare students for college? What should schools and colleges be doing differently? How should state and federal officials help? 相似文献
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罗艳萍 《读与写:教育教学刊》2008,5(6)
The communication of people partially is the communication of cultures. Culture has a direct effect on international commercial activities in all aspects. Different conceptions about time, space, equality, law and the like, lead people to deal with things in different ways. So to know cultures of the counterpart is to facil-itate our enterprises so as to have a smooth and successful communication in commercial activity. 相似文献
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《海外英语》2007,(4):36
There are numbers of crossroads on our long and unpredictable life journey where we totally have no idea about which direction to choose. No matter what our decision is, we should not turn back, but face the music and go ahead instead. I am this kind of girl who always does try without regretting, one example is how I dealt with my love. 相似文献
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Migration occurs behind a variety of reasons and has a great effect on the whole world. People may migrate in order to improve their economic situation, or in order to escape civil strife, persecution, and environmental disasters. The impact of migration is complex, bringing both benefits anddisadvantages. This paper briefly talks about the causes of migration, the allocation of benefits, and the ways in which individual countries and the international community deal with this important subject. 相似文献
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Richard Denner 《海外英语》2007,(4):14-15
Rosco and I wait for the fishermen to return.I sit at a wooden bench near the store at Mt.Baker Resort and watch the clouds change shape. Rosco has my belt around his neck and an eight foot tow chain hooked to a tree. Dogs must be on a leash. Ducks and rabbits are loose. 相似文献
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Sister Carrie is one of the most controversial characters in American literature.Thought as a "fallen woman" firstly,she was defined as a "new woman" by some critics later. However, by digging into the motivaton behind the whole process of Carrie's "success", the relationship between Carrie and her creator (the author), the social conditions of then American, it can be found that Carrie has never been free-standing on her thought and she has never found her real-sdf even after becoming a famous actress. In a society dominated by mass consumerism Carrie is only an adherent of her own desires. She also is a representative of all those country girls flooded into cities, a symbol and a sacrifice of the urbanization of America in a time countryside was overcome by cities. 相似文献
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RUZBEHANI Mohsen 《重庆大学学报(英文版)》2004,3(1):20-25
1.IntroductionOne-cyclecontrolmethod,whichwasproposedaboutonedecadeago[1],hasbecomeanattractivemethodinspecialfieldssuchaspowerfactorcorrection[2-6],switchingamplifiers[7,8],etc.Themainideaofthiscontrollerisbasedonintegrationofdiodevoltageinone-cycleandforcesittobeexactlyequaltothereferencevalue.Themainadvantageofthiscontrollerisitsrealtimeabilitytorejectthevariationofinputvoltage[1].Despitethisgreatability,ithasnogoodperformancesinrejectingofloaddisturbanceandfollowingreferencecommands.Espec… 相似文献