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1.
Suwan种质的特点及在玉米育种中的利用   总被引:3,自引:0,他引:3  
Suwan种质包括Suwan-1群体及含有其基础种质的改良群体、自交系等玉米种质资源.具有适应性好、抗逆性强、配合力高、品质优良等特点,热带、亚热带的许多国家和地区在玉米生产和育种上广泛利用,有合成群体、选育品种间杂交种、改良温带种质等。  相似文献   

2.
导入热带种质的温带玉米自交系的利用潜力   总被引:3,自引:0,他引:3  
用5个热带及亚热带玉米自交系和5个导入热带种质并经连续回交改良的温带玉米自交系, 采用Griffing双列杂交方法III杂交, 共配制90个杂交组合。2008年、2009年以大面积推广杂交种云瑞6号为对照, 对供试自交系进行配合力、杂种优势及利用潜力研究。结果表明, 导入热带种质并经连续回交改良的温带玉米自交系YML598、YML58的多数性状一般配合力效应为极显著正值, 在杂交育种中具有较大的利用潜力;单株产量配合力效应值与诸多产量影响因素的配合力效应值密切相关, 雌雄间隔期、秃尖与单株产量呈负相关, 而其他性状与单株产量呈正相关;产量对照优势H≥10%的组合大多为热带、亚热带种质×改良温带种质, 单株产量特殊配合力效应为极显著正值的组合均为热带、亚热带种质×改良温带种质, 说明热带、亚热带玉米种质与经热带种质改良后的温带玉米种质之间仍具有较强的杂种优势, 且导入热带种质的温带系与热带、亚热带供体系的杂种优势仍然存在, 其所属的杂种优势群并未改变。以热带、亚热带玉米种质为供体, 采用连续回交的方法改良温带玉米自交系是利用热带、亚热带玉米种质的有效方法。  相似文献   

3.
利用113对SSR多态性引物研究了来源比较广泛的56个爆裂玉米自交系的遗传多样性,并初步进行了杂种优势群划分。结果表明:供试自交系问存在较丰富的SSR多态性;56个爆裂玉米自交系可划分为6个杂种优势群,其中Ⅰ,Ⅴ,Ⅵ类群以国内种质选系为主,Ⅱ,Ⅲ,Ⅳ类群主要为外引杂交种选系,第1类群又可分为3个亚群。该分群结果与杂交组合的组配效果相吻合,高优势组合的亲本均属于不同的优势类群(亚群),而在类群(亚群)内未组配出优良组合。SSR标记可以用于研究爆裂玉米自交系的种质基础。  相似文献   

4.
试验采用NCⅡ遗传交配设计,以分属于5个杂种优势群的自交系吉853、S122、龙抗11、铁C 8605-2、丹599为测验种,与5个美国玉米种质改良系组配25个杂交组合,分析5个美国玉米种质改良系的主要农艺性状的配合力及杂种优势.结果表明,自交系WY1和WY3单株产量及相关性状一般配合力表现较好,在玉米育种中有较大的利用潜力;组合WY 3×龙抗11、WY5×吉853、WY4×S122是产量及相关性状特殊配合力综合表现优良的前3个组合;WY3×S122、WY1×S122、WY1×丹599、WY4×S122、WY1×吉853是单株产量总配合力和杂种优势表现突出的组合;美国玉米种质改良自交系可与旅大红骨、塘四平头、温带Ⅰ群类群的玉米自交系杂交组配出强优势的玉米杂交种.  相似文献   

5.
近年来在育种工作中处于种质扩增的需要,很多育种单位引进热带亚热带种质资源进行群体改良和杂交、回交选择,培育出了一批遗传基础丰富的优良自交系,并以这些自交系配制了一批优良杂交种推广应用于生产实践.但在利用热带亚热带玉米种质资源过程中也存在很多问题,本文就这些问题和解决对策作初步阐明.  相似文献   

6.
陈洪梅  番兴明 《种子》2001,(2):57-58,65
热带、亚热带玉米杂交种项目十分重视优良杂交种种质材料的选育,育过程中特别强调种质的耐自交能力,用SD轮回选择法改良耐自交能力是可行的,自交系的选育常用穗行选或系谱法,近几自交系测验种的使用明显增加。世界上广泛利用的热带、亚热带玉米杂种优势群有Tuxpeno,Cubanflints,Coastaltropical flints,ETO和Tuson,把带来、亚热带玉米种质引入温带,可以拓宽温带种质的遗传基础,提高杂种优势潜力,云南省农科院已成功改良了一部分热带、亚热带玉米种质,并在生产中利用。  相似文献   

7.
本研究以分属于5个杂种优势群的自交系B503、B121、B17、B511、B198为测验种,采用不完全双列杂交,与5个先锋玉米种质改良系A101、A203、A302、A306和A425组配25个杂交组合,分析先锋玉米种质改良系的主要农艺性状的配合力及杂种优势。结果表明,改良系A101和A302单株产量及相关性状一般配合力表现较好,在玉米育种方面具有广阔的应用前景;组合A302×B17、AJ425×B503、A306×B121是与产量相关的性状的特殊配合能力综合最优的三种组合;A302×B121、A101×B121、A101×B198、A306×B121、A101×B503是单株产量综合配合力和杂种优势突出的组合。先锋玉米种质改良自交系可与旅大红骨类群、塘四平头、PN78599热带种质玉米自交系杂交组配出强优势玉米杂交种。  相似文献   

8.
热带亚热带玉米引入温带 ,表现出的不适应和许多不良的农艺性状 ,经过观察鉴评—淘汰—选择—温热种质互导—再选择利用 ,能够选获具有新质遗传因素的材料在温带玉米育种中应用 ,可以在一定程度上解决因长期利用地方品种和温带杂交种选系及有限的杂交亲本优势类群 ,造成的杂交种种质遗传基础狭窄的问题。基于这种认识 ,我们继续坚持了 1 978年在国外开始的温热带玉米种质互导选系的研究。“七五”正式申请列入国家玉米育种攻关子专题 ,作为玉米育种素材改良创新方法研究。经2 0年的研究实践 ,选获的优良自交系及组配的新杂交种 ,表明温热带…  相似文献   

9.
基于SSR分子标记的玉米自交系遗传多样性分析   总被引:3,自引:1,他引:2  
了解新选育自交系遗传背景,确定其所属的杂种优势群,是组配杂交组合,选育新的杂交种的关键措施。此研究利用SSR标记技术分析了46份玉米自交系的遗传多样性,结果表明:12对稳定的SSR引物共检测出45个等位基因变异,每个SSR的多态性信息量(PIC)的变幅为0.31~0.76,平均为0.57,显示了较高的多态性。聚类分析显示46个玉米自交系可划分为5个类群,每一类群内所包含的自交系与系谱分析的结果基本一致。研究结果还表明,快捷、准确鉴定种质资源亲缘关系的SSR分子标记技术可以广泛应用于育种实践,提高玉米优势组合选配的效率。  相似文献   

10.
《种子》2021,(4)
采用NCⅡ遗传交配设计,以10份玉米自选系为母本,6份中早熟类玉米自选系为父本,对其进行组配,共得到60份玉米杂交组合,并对F_1代主要农艺性状进行配合力分析。结果表明,JK 83、JK 72、JK 90三个自交系的产量GCA都较高,可选择与其有高配合力的自交系组配出杂种优势强、制种产量和大田产量都很高的组合;JK 36、JK 57出籽率GCA值都较大,有利于产量的提高;JK 36、JK 57可与JK 83、JK 72、JK 90杂交改良,增强自交系产量的优势。JK 302、JK 99散粉-吐丝间隔期(ASI)GCA值较大,说明此自交系抗旱性较强;JK 145×JK 83、JK 206×JK 72、JK 302×JK 66、JK 302×JK 36的SCA值较大,表明这些组合具有较强的杂种优势,有较大利用价值;但是需要进一步进行多年多地区的田间鉴定以确定其是否稳定高产;JK 83、JK 49的抗倒性较强,JK 28、JK 57的水分GCA值较低,以上述自交系组配杂交种有利于大田机械收获和方便干燥仓储。综合农艺性状分析,16份供试美国玉米种质自交系有较大利用价值,但仍需要在品种抗性、适应性等方面进一步改良,以丰富本地区玉米种质基础。  相似文献   

11.
玉米杂种优势的研究对于提高玉米产量和品质有重要意义。对2013年海南三亚种植收获的89份温带自交系、59份热带/亚热带自交系和由这148份自交系随机组配的179份杂交组合进行当代子粒性状的测定。分析了温带玉米与热带/亚热带玉米自交系子粒性状的多样性与差异性,同时依据亲本来源的不同,探索了不同组合的杂交当代子粒性状的差异性。结果表明:温带来源的玉米自交系粒长和百粒重比热带/亚热带材料的粒长和百粒重显著偏长偏重;不同来源的自交系组配的杂交当代F1,母本来源于温带的杂交当代F1粒长显著长于母本来源于热带/亚热带材料;杂种优势分析结果说明,杂交当代F1在粒厚和百粒重性状上表现的相对高亲和相对中亲优势强于粒长和粒宽。  相似文献   

12.
The traditional process of obtaining maize hybrids involves the generation of inbred lines through successive generations of selfing and subsequent testcrosses in order to identify the best combining ability by allelic complementation. A fast alternative to obtain inbred lines is to induce the formation of haploids followed by chromosome doubling. However, even with the aid of haploid-inducing genetic sources, this strategy has not been widely used in maize breeding programs, partly due to difficulties inherent to haploid generation and identification. In order to evaluate the possibility of using dihaploids to generate homozygous maize tropical lines, we used the androgenetic haploid inducer line W23 as a female parent in crosses with the tropical single-cross hybrid BRS1010. Within the progeny of these crosses, 462 seeds were phenotypically selected as putative haploids by the purple-colored endosperm and colorless embryo conditioned by the R1-nj gene. Among these, only four individuals were confirmed as being haploids using SSR markers, chromosome counting and flow cytometry, showing that the phenotypic marker was not efficient in detecting haploids in the tropical maize genotype used. All four haploids as well as some diploid plants presented reduced size, corroborating the difficulties for haploid identification by phenotypic evaluation. Genetic diversity analysis revealed by SSR markers divided the haploids in two groups represented by flint and dent maize inbred lines, which could be helpful in identifying complementary dihaploid lines. The present article demonstrates that a combination of haploid production and SSR fingerprinting is a feasible strategy for maize hybrid development in tropical germplasm.  相似文献   

13.
玉米自交系遗传关系的SSR标记分析   总被引:8,自引:1,他引:7  
选用系谱明确的和系谱来源复杂的38个玉米自交系为材料,在玉米基因组上均匀选取62个SSR引物进行遗传关系分析:(ⅰ)分析SSR引物在这些自交系中的差异程度;(ⅱ)进行自交系的类群划分;(ⅲ) 明确SSR标记在不同来源类型玉米自交系的类群划分和遗传关系分析上的应用价值。62对SSR引物共检测到238个等位基因变异,平均每个位点的等位基因数4.08个,平均多态性信息量(PIC)0.612,平均标记索引系数(MI)2.58,三个指标对标记多态性的分析不完全一致。UPGMA聚类分析将38个玉米自交系分为瑞德、旅大红骨、塘四平头、兰卡斯特、P1、P2和热带素湾7个类群,划群结果与系谱基本吻合,同时对系谱来源复杂的自交系进行分析,明确了它们的归属。  相似文献   

14.
Future maize (Zea mays L.) genetic gains are dependent on the incorporation of unique and useful genetic diversity to breeding programs actively improving germplasm and developing cultivars. Our ultimate goal is to increase the genetic diversity currently available in early maturing maize hybrids by developing novel lines that can be utilized competitively in the northern US Corn Belt. A long-term breeding project (EarlyGEM) was initiated to move US Germplasm Enhancement Maize (GEM) germplasm northward and westward. Nine out of 152 breeding crosses were adapted and data from one breeding cross is presented. Five hundred BC1:S1 lines derived from (AR16026:S17-66-1-B × ND2000) × ND2000 were advanced, selected, and crossed to several commercial testers for early and late generation hybrid testing. Experiments were arranged in various partially balanced lattice designs and grown across 23 North Dakota (ND) environments. Data showed experimental GEM-derived hybrids had better grain yield (10.4 vs. 9.2 t ha?1), test weight (72.5 vs. 70.1 kg h L?1), extractable starch (67.8 vs. 64.2%) and fermentable starch, grain oil (4.3 vs. 3.5%), and grain protein (10.5 vs. 9.4%) when compared to popular hybrids at similar grain moisture at harvest. This is the first research incorporating GEM-derived tropical and late-temperate genetic materials for inbred line development representing a relative maturity (RM) below 90 days. As a consequence of these breeding efforts GEM materials were adapted to the northern US Corn Belt and are not only sources of useful and unique novel genetic diversity but also competitive products for industry use as requests for experimental EarlyGEM lines have been extensive. This research has practical implications with regards to new ways of conducting maize breeding for high latitudes.  相似文献   

15.
Drought stress is thought to promote epicuticular wax accumulation on maize leaves, which reduces plant water loss. We evaluated 62 maize inbred lines and their hybrid testcross progeny for epicuticular wax accumulation on flag leaves at flowering under full and limited irrigation regimes. Extracted wax was measured as a percentage of wax weight to leaf weight (WLW) and leaf area (WLA). Eleven genotypes had above average WLW as both inbred lines and hybrid testcrosses. Thirteen genotypes had above average WLA as either inbred lines or hybrid testcrosses. The drought treatment did not significantly alter WLW or WLA. Heritability of WLW was 0.17 (inbred lines) and 0.58 (hybrid testcrosses). Heritability of WLA was 0.41 (inbred lines) and 0.59 (hybrid testcrosses), suggesting it is a better trait than WLW for epicuticular wax screening. Correlations (r) between inbred lines and their testcross progeny were 0.44 and 0.18, for WLW and WLA, respectively. Heritability of grain weight per ear and plot yield was highest in hybrid testcrosses, with no correlation between inbred and hybrid germplasm. It is not warranted to evaluate epicuticular wax accumulation as the sole drought tolerance mechanism. However, it may be a good secondary trait to observe in relation to grain yield production in hybrids tested under water‐limiting conditions.  相似文献   

16.
为筛选抗粗缩病的糯玉米种质及糯玉米品种,选用64份糯玉米自交系和江苏沿江地区生产上常用的25个鲜食糯玉米品种连续2年进行粗缩病抗性鉴定,结果表明:60%左右的自交系和品种对粗缩病表现为感或高感,且不同的年份、不同的品种、同一品种在不同的年份,对粗缩病的抗性均存在极显著的差异;通系5血统的自交系对粗缩病的抗性要优于其他3类种质;2个糯玉米品种田间鉴定对粗缩病达抗性水平。  相似文献   

17.
墨白种质在黔西北地区玉米育种应用中成效显著。从墨白1号选育了自交系大19,从墨白94号选育了自交系449和405,由449育成了毕单3号等5个玉米杂交种,由405育成了玉米杂交种毕单4号,由大19育成了玉米杂交种黔西4号;由改良自交系449育成了W260和216,由W260育成了毕单10号,由216育成了毕单13号。对墨白种质的改良主要是对骨干代表自交系449和大19进行改良,并育成了一批新选自交系,较自交系449和大19有了质的跨越。  相似文献   

18.
Characterization of genetic diversity among maize inbred lines can facilitate organization of germplasm and improve efficiency of breeding programs. A set of 218 phenotypically diverse inbred maize lines developed at CIMMYT for hybrid production was characterized using 32 RFLP markers to: (1) analyze the genetic diversity present; (2) define potential heterotic groups based on clusters formed with marker data; and (3) identify the most representative testers for each potential heterotic group. Lines were clustered using five different genetic distance measurements to find consensus non-hierarchical clusters. Dendrograms were produced to study hierarchical classification within smaller groups of lines. A very high average allelic diversity was seen in this germplasm. Lines did not cluster based on phenotype, environmental adaptation, grain color or type, maturity, or heterotic response (as determined based on hybrid performance with testers), but lines related by pedigree usually did cluster together. Previously defined testers from opposite heterotic groups were not genetically differentiated, and did not represent well their heterotic group. Discrete clusters were difficult to find; thus, potential heterotic groups will be difficult to suggest using RFLP markers alone. However, suggestions on how to use molecular markers and cross performance information to refine heterotic groups and select representative testers are presented.  相似文献   

19.
Zea mays ssp. mexicana, an annual wild relative of maize, has many desirable characteristics for maize improvement. To transfer alien genetic germplasm into maize background, F1 hybrids were generated by using Z. mays ssp. mexicana as the female parent and cultivated maize inbred line Ye515 as the male parent. Alien introgression lines, with a large range of genetic diversity, were produced by backcross and successive self-pollinations. A number of alien introgression lines with the predominant traits of cultivated maize were selected. Genomic in situ hybridization (GISH) proved that small chromosome segments of Z. mays ssp. mexicana had been integrated into the maize genome. Some outstanding alien introgression lines were evaluated in performance trials which showed 54.6% hybrids had grain yield greater than that of hybrid check Yedan12 which possessed 50% Ye515 parentage, and 17.1, 9.9% hybrids had grain yield competitive or greater than those of Nongda108 and Zheng958, which were elite commercial hybrids in China, respectively. The results indicated that some of the introgression lines had excellent agronomic traits and combining ability for maize cultivar, and demonstrated that Z. mays ssp. mexicana was a valuable source for maize breeding, and could be used to broaden and enrich the maize germplasm.  相似文献   

20.
为了解糯玉米种质的遗传基础,利用29对SSR标记对87份糯玉米自交系进行遗传多样性分析,共检测出180个等位变异,平均每个位点6个等位变异,多态性信息含量变幅为0.308~0.915,平均为0.572。材料间遗传相似系数为0.49~0.93,平均为0.66。通过聚类分析UPGMA (unweighted pair-group method with arithmetic means)方法在遗传相似系数0.64处将87份糯玉米自交系划分为4个类群,分别包含9、66、10和2份材料。此外,利用Structure群体遗传结构分析也将87份糯玉米自交系分为4个类群,分别包含24、25、19和19份材料;进一步分析表明,供试群体中大部分糯玉米自交系的遗传变异较单一。本研究为糯玉米新品种选育和遗传进化分析提供了种质基础和理论依据。  相似文献   

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