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1.
陆地棉12个经济性状配合力及遗传研究   总被引:15,自引:1,他引:14  
按完全双列杂交设计,对7个陆地棉品种的12个经济性状进行了配合力及其遗传的研究。结果表明,单株铃数、子棉产量、皮棉产量、衣分、子指,遗传效应由加性和非加性共同作用;单铃重主要是非加性遗传效应;纤维长度整齐度、比强度、伸长率、麦克隆值,广义遗传力高,狭义遗传力低,非加性效应占主导作用;2.5%跨距长度则主要是加性遗传效应;1%NaCl发芽率遗传效应由加性和非加性共同作用,广义遗传力中偏高,狭义遗传力中。  相似文献   

2.
采用广义法、F_2代群体分离法和回交法估算圆果种黄麻开花期等性状遗传力、遗传进度,遗传变异系数与诸性状的相关系数以及该性状控制基因数目。结果表明,黄麻开花期性状在测试诸性状中遗传力最高,因遗传引起的变化或是环境条件影响程度最小。该性状最小控制基因数目为3对、呈不完全显性,分离规律呈偏斜常态分布,分离群体植株开花期居中间偏早的多,超亲频率约1.5~3%。开花期性状较强的世代传递力和早期稳定性,说明在低世代对该性状的严格选择是有效的。  相似文献   

3.
对杉木全同胞子代林的46个家系8年生和18年生的生长性状进行调查研究,结果表明:树高、胸径、材积及冠幅在不同家系间均存在极显著差异,且均具有较大的广义遗传力,遗传力为0.571 2~0.812 1。树高、胸径、材积及冠幅之间存在极显著的相关性,胸径和材积的相关系数达0.94以上,树高和材积的相关系数达0.80以上。从46个家系中选出2个优良家系,其材积遗传增益分别为44.99%和14.93%。  相似文献   

4.
采用基因型单因素遗传设计,用54份较有代表性的黄麻遗传资源,研究了12个数量性状的相关遗传参数,分析和比较了各性状广义遗传力、狭义遗传力、现实遗传力和相关遗传力;并计算了通过其它性状对产量间接选择的相对效率。本文还进行了相关遗传力通径分析和遗传相关信息与遗传相关贡献的估算,以及主成份等分析。上述研究结果揭示了分枝高度、单株鲜茎重、生长日数等主要数量性状在产量构成及选择中都是至关重要的。  相似文献   

5.
以计算机模拟的方法研究了方差协方差分析法计算的遗传相关系数的抽样分布,以及环境相关和遗传力对抽样分布的影响.遗传力和环境相关对遗传相关系数的绝对值大小和抽样分布有很大的影响。遗传力较高,环境相关较小时,遗传相关系数的分布特征与简单相关系数相似.有关性状的遗传力较低时,遗传相关系数的绝对值趋于增大,有时会出现大于1的异常情况,其分布也比简单相关系数更易出现非正态性.由于遗传力对遗传相关系数抽样标准误的影响,即使自由度相同,遗传相关系数在绝对值上仍无可比性,因此,遗传相关的通径分析是不合理的.  相似文献   

6.
本研究以巴西橡胶树[Hevea brasiliensis (Willd. ex Adr. de Juss) Muell.-Arg.]20个3年生自由授粉后代群体为材料,对其包括产量在内的5个性状(即干胶产量、生长势、树皮厚度、乳管总列数和乳管口径)的遗传变异及选择效果进行了分析评估。试验地点设置在巴西圣保罗州平多拉马(Pindorama)的北部中心试验站。试验采用随机区组设计,重复4次,每小区种植10株。研究结果显示,不同后代群体之间在大多数性状上均存在极显著的遗传差异(p<0.01)。产量、生势、树皮厚度、乳管总列数及乳管口径的基因型方差占各自表型方差的比例分别为13.2%、12.3%、9.4%、3.4%和0.23%,其单株遗传力(h2i)则分别为37%、35%、69%、10%和16%。性状相关分析结果显示,产量与生势、树皮厚度及乳管总列数之间在基因型及表型上均呈极显著正相关。根据以上分析资料,当从20个后代群体中遴选出2个最优群体时,干胶产量及生势2个性状的遗传增益分别为12.3%和6.8%。若从每一后代群体中选出2个最佳的无性系母株,则该2个性状的遗传增益分别为27.7%和9.1%。经过以上2个步骤的选择,该2个性状的遗传增益可分别达到40%和16%。  相似文献   

7.
本研究以巴西橡胶树[Hevea brasiliensis (Willd. ex Adr. de Juss) Muell.-Arg.]20个3年生自由授粉后代群体为材料,对其包括产量在内的5个性状(即干胶产量、生长势、树皮厚度、乳管总列数和乳管口径)的遗传变异及选择效果进行了分析评估。试验地点设置在巴西圣保罗州平多拉马(Pindorama)的北部中心试验站。试验采用随机区组设计,重复4次,每小区种植10株。研究结果显示,不同后代群体之间在大多数性状上均存在极显著的遗传差异(p<0.01)。产量、生势、树皮厚度、乳管总列数及乳管口径的基因型方差占各自表型方差的比例分别为13.2%、12.3%、9.4%、3.4%和0.23%,其单株遗传力(h2i)则分别为37%、35%、69%、10%和16%。性状相关分析结果显示,产量与生势、树皮厚度及乳管总列数之间在基因型及表型上均呈极显著正相关。根据以上分析资料,当从20个后代群体中遴选出2个最优群体时,干胶产量及生势2个性状的遗传增益分别为12.3%和6.8%。若从每一后代群体中选出2个最佳的无性系母株,则该2个性状的遗传增益分别为27.7%和9.1%。经过以上2个步骤的选择,该2个性状的遗传增益可分别达到40%和16%。  相似文献   

8.
本文用拓广表型方差(P)、拓广遗传方差(g)、拓广遗传力(h~2和拓广遗传相关系数(λ)综合地分析了二棱皮大麦形态、生理性状组(株高、剑叶面积、剑叶功能期、剑叶比重、倒二叶面积)、产量性状组(穗数、粒数、千粒重、生物学产量、经济产量)以及籽粒酿造品质组(籽粒蛋白质、千粒重、籽粒皮壳率、粒型指数、籽粒浸出率)的综合遗传力以及性状组间的综合遗传相关关系.遗传力分析表明,性状组的遗传力依次是形态、生理性技组>品质性状组>产量性状组.性状组间遗传相关分析表明,形态生理性状与产量性状组的遗传相关高于与品质性状的遗传相关。  相似文献   

9.
亚麻主要性状遗传力和遗传相关的初步研究   总被引:1,自引:0,他引:1  
遗传力和遗传相关是数量性状遗传研究的主要内容之一。亚麻主要经济性状均属数量性状。在当前亚麻育种工作中,对于数量性状的选择,一般是根据表现型的优劣进行单株选择或系统选择。由于表型效应中包含着不能遗传,而又直接影响选择效果的环境效应部分,因此,研究亚麻数量性状的遗传力和遗传相关,  相似文献   

10.
五十年代以来,欧美及日本学者在提高选择效果方面,对遗传力、遗传相关和遗传进度进行了不少研究。对于这些参数,我国学者庄巧生、沈锦骅已作了系统而简要的阐述。 研究作物数量性状的遗传力、遗传相关和遗传进度可以提高育种效率。因为这些遗传参数能够为育种提供较准确的信息,使系统选育和杂交育种工作能较好地选配亲本和确定杂种的选择时代、方式和进度。我国学者对这些遗传参数的研究,在水稻、小麦等作物方面报导较多,而在油菜作物方面报导较少。李栒、官春云曾用7个甘蓝型品种对油菜主要性状的遗传力和遗传相关进行了研究。  相似文献   

11.
主要介绍甘蔗田间管理机械化作业的术语和定义,作业条件、质量、技术规程,机具要求、保养及安全规则等,旨在为相关甘蔗田间管理作业提供参考。  相似文献   

12.
Arable farmers and their suppliers, consultants and procurers are increasingly dealing with gathering and processing of large amounts of data. Data sources are related to mandatory and voluntary registration (certification, tracing and tracking, quality control). Besides data collected for registration purposes, decision support systems for strategic, tactical and operational tasks yield enormous amounts of mainly digital information. Data of similar nature but with often varying definitions are collected and processed separately for different purposes. This paper describes for an important arable crop – the processing potato – which data requirements and flows exist at present and how they could possibly be described in a unifying ontology. An ontology describes the concepts, attributes and relations in a specific knowledge domain using a standardized representation language. Important concepts in this domain are for example crop, parcel, soil, treatment and farm. The ontology – once elaborated – will reduce the overlap between information models and helps to overcome the problem of data definition and representation. It is a key element for the development of systems that can automatically learn either with the help of expert knowledge or through adequate numerical techniques.  相似文献   

13.
The definitions of the grass growing and grazing seasons as climatic parameters are investigated using a grass growth model. Taking a mean air temperature of 6°C to define the start and end of the growing season at nine UK stations, the model indicates the following: (1) dry matter growth rates at the start are 6 to 9 times greater than those at the end; (2) growth rates at the start of the growing season are higher in those areas where it begins late (i.e. late March/ early April) than in areas where it begins earlier (i.e. late February/ early March). When defining the grazing season in terms of a delay after the start of the growing season, the model indicates that (3) growth rates at the start of the grazing season are higher in upland areas and in areas where the growing season begins late than in lowland areas and in areas where the growing season begins early.
A definition of growing season in terms of growth rates shows that 5 and 8°C are more suitable temperatures to define the start and end than 6°C.
Grazing season was more adequately described using growth rates than in terms of a delay after the start of the growing season.  相似文献   

14.
This informal tutorial is intended for investigators and students who would like to understand the workings of information retrieval systems, including the most frequently used search engines: PubMed and Google. Having a basic knowledge of the terms and concepts of information retrieval should improve the efficiency and productivity of searches. As well, this knowledge is needed in order to follow current research efforts in biomedical information retrieval and text mining that are developing new systems not only for finding documents on a given topic, but extracting and integrating knowledge across documents.  相似文献   

15.
吴平 《茶叶》2015,(2):86-92
通过对《地理标志产品六堡茶》标准与《六堡茶》标准在编写依据和方法、适用范围、术语和定义、分类、等级、要求、试验方法、检验规则等方面的对比,指出两标准的异同。结果显示,《地理标志产品六堡茶》是在《六堡茶》基础上增加六堡茶地理标志产品保护的内容制定而成,增加的内容主要有产品保护范围、原料种植的立地条件和气候条件、茶树品种、栽培技术、采摘、毛茶感官品质和理化指标等,产品等级从7个等级缩减至5个等级,前者比后者要求更宽广、更严格。《地理标志产品六堡茶》标准对保证六堡茶质量特色、提高质量水平,推动六堡茶产业持续健康发展具有引领作用。  相似文献   

16.
随着花生收获机械的推广及其机械种类的日益增多,我国花生收获机械种类和类型的划分以及概念术语等局限性与欠规范性问题日益突出,常常使人概念混淆与功能不清。结合我国花生主产区特别东北花生收获实际并借鉴美国花生收获机械术语,在对我国典型的干花生和鲜食花生收获工艺流程及其主要工艺环节内容研究基础上,对花生收获机械种类、类型、功能和术语等进行了系统分析,论述了我国花生收获机械内涵与种类,提出了花生起挖机、花生起收机、花生捡拾收获机等机械种类和类型划分的主要依据和系列名称等,对人们科学准确地理解花生收获机械相关概念术语、合理选用机械具有重要意义。  相似文献   

17.
蒋敏  章传政 《茶叶通讯》2020,(1):145-151
泛文化现象在中国茶文化界的突出表现为在茶文化学术研究和实际应用领域存在的对有关茶文化概念的混淆模糊、区分不清、认识不足,从而导致茶文化相关概念的严重“泛化”。茶文化本身所具有的边缘性、开放性、综合性特征和各种商业行为对茶文化的过度消费和过度开发,以及茶文化理论研究的不足,严重滞后于茶文化实践的发展等是引起茶文化概念“泛化”现象产生的主要原因。当前,学界需进一步对茶文化、茶艺、茶道等概念及其内涵加以区分、界定,以期达成共识,从而促进茶文化事业的可持续健康发展。  相似文献   

18.
Protected horticulture production represents one of the most important agricultural businesses in Southern Europe. However, many problems related to the lack of mechanisation, intensive use of pesticides, and, in some cases, undesirable residues on food, have not been solved yet. In this context, application technology is a key factor for the improvement of the efficacy and efficiency of plant protection products. Spray guns and knapsack sprayers are the most common technologies that have been used for this purpose. However, several studies have demonstrated that, compared with spray guns, the use of vertical boom sprayers in greenhouses improves spray distribution and reduces labour costs and operator exposure. The main objective of this study was to evaluate the influence of air-assistance on spray application in conventional tomato greenhouses. For this purpose three different spray conceptions were evaluated: 1) a modified commercial handheld trolley sprayer with two air assistance concepts; 2) a self-propelled sprayer; and 3) an autonomous self-propelled sprayer with remote control. All the sprayers considered were evaluated in terms of absolute and normalised canopy deposition, uniformity of distribution, and losses to the ground. In addition, the vertical liquid and air velocity distributions of the sprayers were assessed and compared with the canopy profiles and spray depositions. Yellow tartrazine (E-102 yellow) was used as a tracer for deposition evaluation. The results indicated that increasing the air velocity does not increase the efficiency of a spray application. In general, the modified handheld trolley sprayer showed the best results in terms of deposition and uniformity of distribution, especially at the lowest air assistance rate. These results were confirmed with evaluation of the uniformity of the air and liquid distribution.  相似文献   

19.
The System of Rice Intensification (SRI), developed in Madagascar almost 30 years ago, modifies certain practices for managing plants, soil, water, and nutrients with the effect of raising the productivity of the land, labor, and capital devoted to rice production. Certain production inputs are reduced—seeds, inorganic fertilizer, water, and fuel where water is pumped—with increased yield as a result. This paper introduces the subject of SRI, which is then addressed variously in the articles that follow. SRI is gaining interest and application in over 40 countries around the world. Its practices make soil conditions more aerobic and promote greater root growth, as well as larger, more diverse communities of beneficial soil biota. These below-ground changes support more productive phenotypes above-ground for practically all rice genotypes (cultivars) tested so far, with supportive evidence accumulating both from scientific institutions and field applications. SRI methodology remains controversial in some circles, however, because of the transformational change it introductions into traditional lowland rice production systems. This issue of PAWE brings together the results of formal research on SRI in a number of countries (Part I) and also reports on initiatives by government agencies, NGOs, universities, or the private sector, bringing knowledge of SRI to farmers in a wide range of agroecological circumstances (Part II). This introduction presents the basic principles that underlie SRI and discusses the nature of this innovation as well as considers some of the issues in contention. SRI continues to evolve and expand, being a work in progress. Its concepts and methods are being extended also to upland (rainfed) rice production, as well to other crops. Accordingly, SRI should not be regarded or evaluated in conventional terms as if it were a typical component technology. It is understood more appropriately in terms of a paradigm shift for rice production. In particular, it calls into question the long-standing belief that rice is best produced under continuously flooded conditions.  相似文献   

20.
植物品种保护与品种审定、品种认定虽然在某些方面有共同点,但之间在许多方面存在着不同,且不可替代。本文从几个方面来进行比较,以供参考。  相似文献   

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