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大垄窄行密植栽培是指以垄作为基础,将原两垄合成一垄,垄上种植6行的窄行密植栽培方法。选用适宜品种是大豆大垄窄行密植栽培的核心技术。本试验的目的就是要筛选出适合大垄窄行密植栽培的大豆新品系。通过本试验我们认为,大垄窄行密植宜选择半矮秆抗倒伏品种,最适合的品系是绥98—6027和绥98—6007,建议示范利用。 相似文献
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为研究新余地区镉污染稻田治理方法,筛选稻田替代种植经济作物,以赣葛1号为试验材料,设置2种栽培方式(平作、垄作),分析起垄栽培对土壤理化性质、镉含量、粉葛葛根产量、生物量及其对重金属镉富集的影响。结果表明,与平作栽培相比,垄作栽培增加了粉葛块根产量(13.96%)和地上部生物量(7.02%)。垄作栽培增加了土壤pH、有机质、阳离子交换量、全镉和有效态镉含量,增幅分别为7.34%、11.48%、0.97%、16.67%和8.00%。垄作栽培还提高了粉葛块根、葛渣、葛头和叶片中镉含量,分别增加了67.74%、52.24%、20.51%和5.43%,但减轻了葛粉、主藤和侧枝中镉含量,分别降低了20.00%、10.13%和3.54%。粉葛不同部位中镉含量表现为:侧枝>主藤>葛头>叶片>块根。综上,起垄栽培可改善土壤环境,提高粉葛产量和生物量,但有增加土壤和粉葛中镉含量的风险。 相似文献
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本文利用三种根癌农杆菌(Agrobacterium tumefaciens)分别感染我国的野生、半野生和栽培大豆的子叶,诱发产生肿瘤.结果发现根癌农杆菌,A281、Chry5,Chry5C对我国的栽培大豆均有致瘤作用,且A_(281)对栽培大豆具有超毒作用.这一结果与其对美国栽培大豆的作用结果是一致的.而A281对半野生大豆的致瘤作用较差,对野生大豆的致瘤作用最弱.而根癌农杆菌Chry5C尽管其毒性已被弱化,但对我国的栽培大豆仍具有致瘤作用,这一结果与它对美国栽培大豆的致瘤作用是有差异的.说明我国的栽培大豆与美国的栽培大豆之间在致瘤方面存在差异.Chry和5Chry5C对我国的野生大豆和半野生大豆几乎是不致瘤的,说明了野生大豆和半野生大豆在Ti质粒致瘤方面与栽培大豆存在区别.这为进一步研究我国的大豆品质和野生大豆、半野生大豆的特性提供了另一种有效的途径,也为今后进行大豆遗传工程选择适当的受体材料提供了基础. 相似文献
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"增强子陷阱"技术是建立果蝇脑全基因组表达图谱及其数据库的重要方法.筛选获得新特异表达的GAL4品系,可为进一步研究果蝇脑神经在学习记忆功能提供强有力的基因工具.通过"增强子陷阱"技术来获得果蝇突变体,并与报告转基因果蝇(UAS-EGFP)杂交,用荧光显微镜观察成年果蝇脑内荧光分布,从而获得该突变体的脑基因表达图谱,在此基础上利用JavaScript来建立果蝇脑全基因组表达数据库.目前获得基因突变体果蝇2 677种,大部分在果蝇脑中有表达,其中在果蝇嗅觉学习记忆相关脑区蘑菇体表达的基因有368个,且有部分基因特异地表达在某些传导通路上.这些果蝇基因突变体库及其表达图谱为进一步研究各基因的功能及作为遗传工具来研究各脑区结构和功能提供极大方便. 相似文献
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栽培稻×大颖野生稻F~2 多倍现象的细胞遗传学研究 总被引:3,自引:0,他引:3
A栽培稻(Oryza sativa)×大颖野生稻(Oryza grandiglumis)F2经细胞学鉴定为2n=4x=48, 即已由杂种F1的ACD异源三倍体变成了异源四倍体。研究了从粗线期到末期Ⅱ的染色体行为,结果表明,F2的染色体构型为异源节段异段类型,且异常染色体频率极高,合计为87.13%。各类异常染色体频率变化按比例大小依次为: 单价体,染色体拖曳,落后染色体,多价体,邻接型易位,不均等分离,桥,不分离和松散配对等。邻接型易位是本研究的中心论题。因邻接型易位的存在是F2花粉不育的一个重要原因, 也是产生节段异段染色体构型的重要原因;因邻接型易位带来相互易位,可供育种利用。
Abstract:The chromosome number in F2 of O.sativa×O.grandiglumis were 2n=4x=48.This showed that the allotriploid of hybrid F1 had been changed into allotetraploid in F2.The chromosome constitution of this allotetraploid remained to be determined.The chromosome behavior was studied during meiosis from pachytene to telophase II.Results showed that the chromosome configuration of F2 belonged to the type of the nodal section-allosection,and possessed very high rate of anomalous chromosome,the total rate of anomalous chromosome accounting for 87.13%.The frequency of anomalous chromosome were ranked as follows:univalent,chromosome straggling,lagging chromosome,polyvalent,adjoin translocation,unequal division,chromosome bridge,non-disjunction and loose pairing in descent order.The adjoin translocation was the topic in this study.With this translocation,no vitality gamentes were produced in F2.However,this is a mutual translocation,hence that is very useful for breeding. 相似文献
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在2003-2005年间,对604份玉米种质进行了抗弯孢菌叶斑病和玉米螟鉴定,筛选出抗弯孢菌叶斑病的材料93份,抗玉米螟材料22份。2006-2009年间,对836份玉米种质进行了抗大斑病、茎腐病、穗腐病和瘤黑粉病的鉴定与评价,筛选出一批高抗和多抗的资源。在836份资源中,对大斑病1、2和N号3个生理小种具有抗性的材料均为50%左右;抗茎腐病材料为41.3%,高抗和抗性种质分别为264和81份;穗腐病高抗和抗性种质分别为5和171份,占比为21.1%;瘤黑粉病高抗和抗性种质各261和14份,占总鉴定材料的32.9%。上述结果表明抗大斑病、茎腐病和瘤黑粉病的种质资源较为丰富。通过对抗性结果进行对比分析,发现不同生态区玉米种质的抗性强弱以及抗性多样性存在明显差异,黑龙江和内蒙的种质对病虫害的抗性强弱及多样性程度明显高于四川种质。此外,玉米自交系对病虫害的抗性强弱以及多抗性程度高于农家种。 相似文献
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玉米种质资源对六种重要病虫害的抗性鉴定与评价 总被引:11,自引:0,他引:11
在2003-2005年间,对604份玉米种质进行了抗弯孢菌叶斑病和玉米螟鉴定,筛选出抗弯孢菌叶斑病的材料93份,抗玉米螟材料22份。2006-2009年间,对836份玉米种质进行了抗大斑病、茎腐病、穗腐病和瘤黑粉病的鉴定与评价,筛选出一批高抗和多抗的资源。在836份资源中,对大斑病1、2和N号3个生理小种具有抗性的材料均为50%左右;抗茎腐病材料为41.3%,高抗和抗性种质分别为264和81份;穗腐病高抗和抗性种质分别为5和171份,占比为21.1%;瘤黑粉病高抗和抗性种质各261和14份,占总鉴定材料的32.9%。上述结果表明抗大斑病、茎腐病和瘤黑粉病的种质资源较为丰富。通过对抗性结果进行对比分析,发现不同生态区玉米种质的抗性强弱以及抗性多样性存在明显差异,黑龙江和内蒙古的种质对病虫害的抗性强弱及多样性程度明显高于四川种质。此外,玉米自交系对病虫害的抗性强弱以及多抗性程度高于农家种。 相似文献
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小麦种质对麦长管蚜的抗性鉴定与评价 总被引:11,自引:0,他引:11
2002-2005年连续4年,选用蚜情指数法对小麦种质进行麦长管蚜田间自然感蚜抗性鉴定,从2000份小麦种质中筛选出不同抗性材料34份,占总鉴定材料的1.7%,其中高抗种质5份、抗性种质9份、中抗种质20份。利用苗期室内接虫法,对部分抗感小麦种质进行鉴定,结果表明,苗期的抗性表现与成株期基本一致。对杂交组合临远207(抗)×Witchita(感)的F1、F2的抗性遗传分析表明,临远207对麦长管蚜的抗性由1对显性单基因控制。 相似文献
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Pollen and phytolith evidence for rice cultivation during the Neolithic at Longqiuzhuang, eastern Jianghuai, China 总被引:8,自引:0,他引:8
Phytolith and pollen analyses were carried out at the archaeological site at Longqiuzhuang in Gaoyou, Jiangsu, southern China. The results indicate that the key morphological phytolith types associated with cultivated rice (Oryza) are common in the Neolithic cultural layers at this site. The evidence strongly suggests that cultivated rice (mainlyO. japonica) was grown locally during the Neolithic. The archaeopalynological record provides information about the impact of human activity and, in particular, farming on the natural vegetation. The evergreen and deciduous broad-leaved forest was substantially altered, and herbaceous taxa, including ruderals, expanded. Based on the results from the phytolith and pollen analyses, two distinct phases of human activity have been recognized, namely (1) phase A (7000-6300 B.P., i.e. early Neolithic) a warm and humid period when arable farming, including rice cultivation, was pursued but the variation in the size of the carbonized rice grains was low, and (2) phase B (6300-5500 B.P., late Neolithic age), a period of relatively cold and/or arid climate when cultivated rice was of major importance and was morphologically similar to present-day rice. Environment, and in particular climate change in the late Neolithic, were important factors affecting the development of rice as a cultivated crop. It was mainly during this period that artificial selection favoured the emergence of forms similar to those of today. 相似文献
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Bretz K Ilijevic S Grüneberg M Becker U Syldatk C 《Biotechnology and bioengineering》2006,95(6):1023-1031
Autolysis of riboflavin-producing B. subtilis can be induced by pH, lack of carbon source, and the buffer system. Stress factors like temperature shift or oxygen dearth enhance the autolysis process. After cultivation of a riboflavin-producing strain, the pH of the whole culture broth was adjusted to 6.5-7.5. At a temperature of 40 degrees C, autolysis started after 1 h. Adding a defined amount of commercially available endo- and exo-proteases enhanced both auto- and proteo-lysis. Optimization of endo- and exo-protease concentrations and of the time increased the degree of proteolysis. Additionally, the amount of DNA and Protein trapped in the riboflavin crystals could be significantly reduced by autolysis. After autolysis, the cultivation broth was centrifuged and the supernatant was cross-flow filtrated with a cut off of 10 kDa. Using this autolysate instead of yeast extract as a medium component for riboflavin production with B. subtilis, a riboflavin yield of 77% was obtained in comparison with the standard cultivation on yeast extract. 相似文献
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José Renato Pereira Cavallazzi Osmar Klauberg Filho Sidney Luiz Stürmer Paul T. Rygiewicz Margarida Matos de Mendonça 《Plant Cell, Tissue and Organ Culture》2007,90(2):117-129
Santa Catarina state is the largest producer of apples in Brazil. Soils in this region have low pH and high levels of aluminum and manganese, requiring high inputs of fertilizers and amendments increasing costs of apple production. Inoculation of arbuscular mycorrhizal fungi can improve the establishment of micropropagated apple plants in such adverse soil conditions. Soil samples were collected from apple orchards in the Caçador, Fraiburgo and São Joaquim regions to develop a corn bioassay to identify mycorrhizal communities with high infectivity. Eleven fungal species were identified from one Caçador soil with the highest infectivity. Glomus etunicatum SCT110, Scutellospora pellucida SCT111, Acaulospora scrobiculata SCT112 and Scutellospora heterogama SCT113 were brought into single-species culture and used in a plant growth and nutrient uptake experiment using micropropagated apple (Malus prunifolia), cultivated at three soil pH. Colonization by fungal isolates significantly affected plant height, shoot and root dry weights, and root:shoot ratio. Soil pH also significantly affected all growth parameters except shoot dry weight. Mycorrhizal inoculation also significantly altered tissue concentrations of P, Zn, Cu, Ca, S, Na, N, K, Fe and Al. Association with mycorrhizal fungi increased P concentration and also decreased Al concentrations in the shoots. Overall, G. etunicatum and S. pellucida were the most effective isolates to promote plant growth and nutrient uptake. Inoculation of apple rootstock with selected fungal isolates during the acclimatization stage represents a useful strategy for producing micropropagated apples that can withstand acidic soil conditions. 相似文献