共查询到19条相似文献,搜索用时 62 毫秒
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遗传多样性是一种重要的自然资源且在未来育种进展中将起到关键性作用。必须要对收集的遗传多样性种质进行有效利用和管理方面的鉴定研究工作。种质收集的最佳规模是要求保留最大的遗传变异和保持最小的冗余性为好。 相似文献
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玉米种质资源是选育优良品种的遗传物质基础,收集原始素材,拓宽种质基础,开展种质鉴定、创新和利用,在玉米品种改良工作中始终占有重要地位。从全球范围来看,大约有300个玉米地方种族,但广泛开发利用的只有5~6个。种质资源狭窄也是当前我国玉米育种和生产的突出矛盾,杂交玉米育种中每一次突破性品种的诞生,总是以突破性的基础材料和自交系为前提。为了扩大玉米遗传育种的种质基础,自20世纪80年代以来,我国育种家对热带。 相似文献
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新疆地区是中国玉米高产区之一,年玉米面积4万hm2.80年代以前,新疆玉米以农家种为主,籽粒和茎秆产量都很低,经济效益不高. 相似文献
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把热带亚热带玉米种质按25%~75%的不同比例导入温带玉米自交系或育种材料中,进行种质改良和创新研究。选育的热导自交系种质基础较宽;配合力较高;玉米大、小斑病病情指数分别降低61.5%~78.9%和53.8%~69.4%;青枯病、病毒病株率分别降低84.1%~93.2%和86.7%~98.2%;成熟期绿叶数增加2.6~4.4倍;自交系自身产量提高20.0%~55.6%。表明热带亚热带种质导入温带玉米,可能是拓宽温带玉米种质基础、提高综合抗性和丰产性、创造新种质等方面的有效途径之一。 相似文献
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贵州山区玉米种质的改良 总被引:2,自引:0,他引:2
贵州山区玉米种质对贵州省的玉米育种和玉米生产有着重大贡献,但贵州山区玉米种质需要进行遗传改良和扩增,才能发挥良好作用。本文概述了贵州山区玉米种质的特点及其改良情况,并对贵州山区玉米种质的改良发展方向进行了讨论。 相似文献
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TUXPENO种质在玉米育种中的利用张志国(贵州省毕节地区农科所毕节551700)1Tuxpeno种质的特点Tuxpeno玉米种质是国际玉米小麦改良中心(CImmYT)合成的重要群体。Tuxpeno种质与ETO或Suwan等种质构成了热带地区玉米杂交…… 相似文献
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在玉米育种方案中利用外来种质的途径 总被引:4,自引:0,他引:4
热带种质的光周期敏感性所谓外来种质是指那些非本地区原产的种质,它们可能是不适应或不能直接适应本地生长条件的玉米材料。在本文范围内将着重讨论引自玉米多样性中心的种质,即热带和亚热带种质。 相似文献
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十堰市地处湖北省西北部,二高山气候比较典型,山地多、平地少、旱地多、水地少。十堰市农科院立足本地区地理条件,加大玉米新品种选育、推广力度。在各级领导专家关怀、支持、协助下,先后选育出陨单1号、鄂玉10号、鄂玉14号、鄂玉16号、鄂玉25号一系列品种。特别是在鄂玉16号的基础上,成功地把热带种质导入鄂玉16号的父本系,经连续自交获得新系美C,组配后选育出国审新品种鄂玉25号,对常规育种手段是一个很好的创新和补充。 相似文献
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中国玉米种质资源的整理与成就 总被引:16,自引:1,他引:16
玉米种质资源是选育优良品种的遗传物质基础,搜集原始素材,拓宽种质基础,开展种质鉴定,创新和利用,在玉米品种改良工作中中有重要地位。 相似文献
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Summary Relationships between whole-plant and germination NaCl tolerance and two in vitro measures of NaCl tolerance were evaluated in lucerne (Medicago sativa L.). No significant correlations were observed between relative NaCl tolerance of non-regenerating callus cultures, herbage regrowth, seed or pollen germination, and pollen tube growth. Simulated selection using indirect measures of NaCl tolerance produced small expected gains in relative NaCl tolerance during herbage regrowth and seed germination. These gains were less than 30% of those expected with direct selection for regrowth or germination tolerance. Selection based on the apparent NaCl tolerance of callus tissue or male gamephytes would appear unproductive. Direct selection for NaCl tolerance both at germination and during mature plant regrowth would appear to be necessary to rapidly develop lucerne populations with field-relevant levels of tolerance to NaCl stress.Approved by the Arizona Agric. Expt. Stn. as Journal Series no. 5015. 相似文献
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玉米耐低温种质资源的初步鉴定和筛选 总被引:1,自引:0,他引:1
摘要:本试验对654份玉米自交系的耐低温特性进行了鉴定,在常温(25℃)和低温(10℃)胁迫下分别测定种子的发芽率以及低温胁迫下的发芽时间。以相对发芽率和平均发芽时间作为耐低温特性评价指标,通过聚类分析筛选到30份强耐低温自交系和43份对低温胁迫强敏感自交系,为培育耐低温玉米新品种和挖掘耐低温相关基因提供种质资源。 相似文献
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Pengfei Leng Milena Ouzunova Matthias Landbeck Gerhard Wenzel Thomas Lübberstedt Birte Darnhofer Joachim Eder 《Plant Breeding》2019,138(5):524-533
Improving maize starch content is of great importance for both forage and grain yield. In this study, 13 starch degradability traits were analysed including percentage of the seedling area, floury endosperm, hard endosperm of total grain area, percentage of the floury endosperm surface and vitreousness ratio surface hard: floury endosperm surface, etc. We mapped quantitative trait loci (QTL) in a biparental population of 309 doubled haploid lines based on field phenotyping at two locations. A genetic linkage map was constructed using 168 SSR (simple sequence repeat) markers, which covered 1508 cM of the maize genome, with an average distance of 9.0 cM. Close phenotypic and genotypic correlations were found for all traits, and were all statistically significant (p = 0.01) at two locations. Major QTL for more than two traits were detected, especially in two regions in bins 4.05–4.06 and 7.04–7.05, associated with 13 and 9 traits, respectively. This study contributes to marker‐assisted breeding and also to fine mapping candidate genes associated with maize starch degradability. 相似文献
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Xiaocong Zhang Hongjun Yong Zhiqiang Zhou Chaoshu Zhang Ming Lu Qi Sun Lin Zhang Mingshun Li Degui Zhang Jianfeng Weng Zhuanfang Hao Shihuang Zhang Zhenhua Wang Xinhai Li 《Euphytica》2017,213(2):45
Understanding the combining ability and heterosis of available germplasm is a prerequisite for successful maize improvement and breeding. The objectives of this study were to analyze the combining ability and heterosis of seven representative maize germplasm populations, and further, to evaluate their potential utility in germplasm improvement. A total of 21 crosses were made among these seven populations in a complete diallel without reciprocals. The parental populations and 21 crosses were evaluated for days to silking (DS), ear height (EH), and grain yield (GY) in the Northeast and Yellow and Huai River maize growing areas in China in 2012. Csyn5, Csyn7, Cpop.11, and Cpop.12 had desirable general combining ability (GCA) effects for DS and EH in both the Northeast China mega-environment (NCM) and the Yellow and Huai River Regions of China mega-environment (YHCM). Cpop.11 possessed a favorable GCA effect for GY in the NCM, as did Csyn5, Cpop.17, and Cpop.18 in the YHCM. Csyn6 and Csyn7 exhibited tremendous yield-enhancing potential in both mega-environments. Additionally, six combinations including Csyn7 × Csyn6, Csyn5 × Csyn6, Cpop.11 × Cpop.18, Cpop.12 × Cpop.17, Csyn7 × Cpop.17, and Csyn5 × Csyn7 exhibited better specific combining ability effects for GY, yield performance, and mid-parent heterosis in the appropriate mega-environment. These results indicated that the seven populations would be very useful for the improvement of related agronomic traits, and the six candidate combinations possessed great potential for further improvement and utilization. 相似文献