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1.
Khandakar M. Iftekharuddaula Muhammad A. Salam Muhammad A. Newaz Helal U. Ahmed Bertrand C. Y. Collard Endang M. Septiningsih Darlene L. Sanchez Alvaro M. Pamplona David J. Mackill 《Breeding Science》2012,62(3):216-222
Marker assisted backcrossing has been used effectively to transfer the submergence tolerance gene SUB1 into popular rice varieties, but the approach can be costly. The selection strategy comprising foreground marker and phenotypic selection was investigated as an alternative. The non-significant correlation coefficients between ranking of phenotypic selection and ranking of background marker selection in BC2F1, BC3F1 and BC3F2 generations indicated inefficiency of phenotypic selection compared to marker-assisted background selection with respect to recovery of the recipient genome. In addition, the introgression size of the chromosome fragment containing SUB1 was approximately 17 Mb, showing the effects of linkage drag. The significant correlation coefficient between rankings of phenotypic selection with the percentage of recipient alleles in the BC1F1 generation suggested that background selection could be avoided in this generation to minimize the genotyping cost. The phenotypically selected best plant of the BC3F1 generation was selfed and backcross recombinant lines were selected in the resulting BC3F4 generation. The selection strategy could be appropriate for the introgression of SUB1 QTL in countries that lack access to high-throughput genotyping facilities. 相似文献
2.
K. M. Iftekharuddaula M. A. Newaz M. A. Salam H. U. Ahmed M. A. A. Mahbub E. M. Septiningsih B. C. Y. Collard D. L. Sanchez A. M. Pamplona D. J. Mackill 《Euphytica》2011,178(1):83-97
Flooding is one of the major hazards of rice production for the rainfed lowland rice ecosystem, and tolerant cultivars are
urgently needed to help protect farmers from submergence damage. A quick and efficient strategy was implemented to introgress
SUB1, a major QTL for submergence tolerance, into a rainfed lowland mega variety BR11 of Bangladesh by only two backcrosses and
one selfing generation. In marker-assisted backcrossing (MABC), one tightly-linked simple sequence repeat (SSR) and two gene-based
markers, four flanking SSR and 116 background SSR markers were used for foreground, recombinant and background selection,
respectively, in backcrosses between a SUB1 donor IR40931-33-1-3-2 and BR11. BR11-Sub1, identified in a BC2F2 plant, possessed BR11 type SSR alleles on all fragments analyzed except the SUB1 QTL. The introgression size in BR11-Sub1 was 800 Kb indicating approximately 99.8% identity to BR11. BR11-Sub1 along with
other introgression lines showed submergence tolerance similar to the tolerant parent. Yield, yield-component parameters and
grain physico-chemical properties showed successful recovery of the BR11 traits in BR11-Sub1, with yield potential ranging
from 5.2 to 5.6 t/ha, not significantly different from the recurrent parent mega variety BR11. Producing a large number (~1000)
of backcross F1 plants was considered essential to achieve recombination on both sides of the gene, limiting linkage drag with only two backcrosses.
A large number of background markers ensured proper recovery of the recurrent parent genome in the BC2F2 generation. The study demonstrates a rapid and highly precise strategy to introgress a major QTL by BC2F2 generation into a modern rice variety using an unadapted donor. The variety can replace BR11 on more than 2 million of ha
in Bangladesh and provide major increases in rice production. 相似文献
3.
Vijayakumar Koraboyana Balwinder Singh Gill Asmita Sirari Gaurav Khosla Shayla Bindra Vineet Kumar 《Plant Breeding》2023,142(2):140-148
Introgression of yellow mosaic disease (YMD) resistance and effect of recurrent parent genome (RPG) on grain yield was studied in 84 soybean genotypes from four populations namely, F2:7, BC1F6, BC2F5 and BC3F4 derived from cross JS335 x SL525. It was observed that in F2:7, BC1F6, BC2F5 and BC3F4 derived lines, RPG contribution was 42.5%, 54.9%, 66.4% and 77.6%, respectively, which is significantly less than expected values. Linkage drag from donor parent with YMD resistance gene may be a possible reason for such deviations. Average grain yield per plant in F2:7, BC1F6, BC2F5 and BC3F4 generations was observed as 13.0, 14.3, 14.9 and 16.1 g, respectively. It was observed that genotypes with more than 80% RPG observed to have both YMD resistance and good yield potential. Graphical genotyping (GGT) analysis revealed that maximum RPG was recovered in chromosomes 8 and 10 and maximum introgression occurred in chromosomes 6 and 19. Our results demonstrated that RPG was positively associated with yield as evident from yield increase with increase in RPG. 相似文献
4.
本文报道了水稻第1染色体长臂上微效千粒重QTL qTGW1.2的验证和分解。针对前期qTGW1.2定位结果, 应用SSR标记检测, 从籼籼交组合珍汕973/密阳46衍生的1个BC2F7分离群体中, 筛选到杂合区间分别为RM11621-RM297和RM212-RM265的2个单株, 构建了两套BC2F8:9近等基因系, 将qTGW1.2进一步界定在RM212-RM265及其两侧交换区间的区域内。在此基础上, 筛选出5个在目标区间内分离片段缩小且呈阶梯状排列的单株, 衍生了5套BC2F10分离群体, 应用Windows QTL Cartographer 2.5进行QTL分析。结果表明, 每套群体均检测到千粒重QTL, 加性效应为0.13~0.38 g, 来自密阳46的等位基因提高千粒重; 经比较各个群体的分离区间, 将qTGW1.2分解为互引连锁的2个QTL, 其中, qTGW1.2a位于RM11730和RM11762之间934 kb的区域内, 呈加性作用, qTGW1.2b位于RM11800和RM11885之间2.1 Mb的区域内, 呈正向超显性。 相似文献
5.
Jing Li Peng Xu Xianneng Deng Jiawu Zhou Fengyi Hu Jianmin Wan Dayun Tao 《Euphytica》2008,164(3):699-708
To further understand the nature of hybrid sterility between Oryza sativa and Oryza glaberrima, quantitative trait loci (QTL) controlling hybrid sterility between the two cultivated rice species were detected in BC1F1 and advanced backcross populations. A genetic map was constructed using the BC1F1 population derived from a cross between WAB450-16, an O. sativa cultivar, and CG14, an O. glaberrima cultivar. Seven main-effect QTLs for pollen and spikelet sterility were detected in the BC1F1. Forty-four sterility NILs (BC6F1) were developed via successive backcrosses using pollen sterility plants as female and WAB450-16 as the recurrent parent.
Seven NILs, in which the target QTL regions were heterozygous while the other QTL regions as well as most of the reminder
of the genome were homozygous for the WAB450-16 allele, were selected as the QTL identification materials. BC7F1 for the seven NILs showed a continuous variation in pollen and spikelet fertility. The four identified pollen sterility QTLs
were located one each on chromosomes 1, 3, 7 and 7. Pollen sterility loci qSS-3 and qSS-7a were on chromosomes 3 and 7, respectively, which coincides with the previously identified S19, and S20, while loci qSS-1 and qSS-7b on chromosomes 1 and 7L appear distinct from all previously reported loci. An epistatic interaction controlling the hybrid
sterility was detected between qSS-1 and qSS-7a. 相似文献
6.
Maize kernel row number (KRN) is an important agronomic trait. In this study, 13 quantitative trait loci (QTL) for maize KRN were identified in different environments using F2:3 and F2:4 populations developed from two inbred lines. These QTL are distributed on chromosomes 2,3,5,8 and 10, and the genic effects are additive or partially dominant. Using the BC3F2:3 populations developed from the same parental lines, QTL of KRN located on chromosomes 5 and 10 were also identified in two environments. Three BC5F2:3 populations were used to confirm the major QTL for KRN between ssr1430 and umc1077 on chromosome 10(qKRN10). This result will facilitate the fine mapping and map‐based cloning of this major QTL in the future. 相似文献
7.
Kuljit Kaur Cheema Navtej S. Bains Gurjit S. Mangat Aparna Das Yogesh Vikal Darshan S. Brar Gurdev S. Khush Kuldeep Singh 《Euphytica》2008,160(3):401-409
Modern rice varieties that ushered in the green revolution brought about dramatic increase in rice production worldwide but
at the cost of genetic diversity at the farmers’ fields. The wild species germplasm can be used for broadening the genetic
base and improving productivity. Mining of alleles at productivity QTL from related wild species under simultaneous backcrossing
and evaluation, accompanied by molecular marker analysis has emerged as an effective plant breeding strategy for utilization
of wild species germplasm. In the present study, a limited backcross strategy was used to introgress QTL associated with yield
and yield components from Oryza rufipogon (acc. IRGC 105491) to cultivated rice, O. sativa cv IR64. A set of 12 BC2F6 progenies, selected from among more than 100 BC2F5 progenies were evaluated for yield and yield components. For plant height, days to 50% flowering and tillers/plant, the introgression
lines did not show any significant change compared to the recurrent parent IR64. For yield, 9 of the 12 introgression lines
showed significantly higher yield (19–38%) than the recurrent parent IR64. Four of these lines originating from a common lineage
showed higher yield due to increase in grain weight and another three also from a common lineage showed yield increase due
to increase in grain number per panicle. For analyzing the introgression at molecular level all the 12 lines were analyzed
for 259 polymorphic SSR markers. Of the total 259 SSR markers analyzed, only 18 (7.0%) showed introgression from O. rufipogon for chromosomes 1, 2, 3, 5, 6 and 11. Graphical genotypes have been prepared for each line and association between the introgression
regions and the traits that increased yield is reported. Based on marker trait association it appears that some of the QTL
are stable across the environments and genetic backgrounds and can be exploited universally. 相似文献
8.
Zhang-Ying Xi Feng-Hua He Rui-Zhen Zeng Ze-Min Zhang Xiao-Hua Ding Wen-Tao Li Gui-Quan Zhang 《Euphytica》2008,160(3):369-377
Backcrossing is a trait introgression method of renewed importance in crops. The evolution of introgressed or substituted
segments through backcross generations has been analyzed theoretically using simulations. In this study, the content of donor
genomes, including donor segment number (DSN), donor segment length (DSL), and donor genome size (DGS), were directly analyzed
in six crosses over three successive backcrosses using a set of single sequence repeat (SSR) markers covering the entire rice
genome. The results of this analysis demonstrated that the average DSN in each genome was 8.39 in BC2F1, 4.13 in BC3F1, and 2.41 in BC4F1, decreasing nearly by half with each backcrossing. The average DSL was 33.43 cM (centiMorgans) in BC2F1, 29.04 cM in BC3F1, and 25.07 cM in BC4F1, display a progressive decrease slightly greater than 10% in each additional backcross generation. Meanwhile the average
DGS was 280.51 cM in BC2F1, 119.97 cM in BC3F1, and 60.53 cM in BC4F1, decreasing 57.2% from BC2F1 to BC3F1 and 50.4% from BC3F1 to BC4F1. This revealed that the reduction in DGS was approximately 50% with each backcrossing. These results provide a guide for
introgression or substitution of target chromosome segments from donors into recipients in backcross programs.
Zhang-Ying Xi and Feng-Hua He contributed equally to this work. 相似文献
9.
Matthias H. Herrmann Jianzhong Yu Steffen Beuch Wilhelm E. Weber 《Plant Breeding》2014,133(5):588-601
Using the advanced backcross quantitative trait loci (AB‐QTL) strategy, we successfully transferred and mapped valuable allelic variants from the high β‐glucan (BG) accession IAH611 (PI 502955), into the genome of cultivar ‘Iltis’. By backcrossing one BC1F1 plant to ‘Iltis’, we developed two BC2F2‐6 populations A and B, comprising 98 and 72 F2‐individuals, respectively. Genotyping of BC2F2 individuals with predominantly AFLP markers resulted in 12 linkage groups with a map size of 455.4 cM for Population A and 11 linkage groups with a map size of 313.5 cM for Population B. Both populations were grown at three sites in Germany over a three‐year period. Individuals were then phenotyped for 13 traits including grain yield (YD) and β‐glucan content (BG). QTL analysis via stepwise regression detected a total of 33 QTLs, most of which were clustered in three linkage groups. Two dense linkage groups A1 and B13 were found to be putatively homologous to groups KO_6 and KO_11 of the ‘Kanota’/‘Ogle’ map, respectively. 相似文献
10.
Two related segregating populations of Theobroma cacao L. were analysed for their resistance to Phytophthora palmivora. The first F1 population was obtained by crossing two susceptible cacao clones of Catongo (a highly homozygous genotype) and Pound 12(a
highly heterozygous genotype) and the second population was obtained by backcrossing a single F1 tree with Catongo. The genetic maps obtained for each population were compared. The F1 map includes 162 loci and the backcross has 140 loci. The two maps, F1 and BC1, exhibit high co-linear loci organization covering respectively, 772 and 944 cM.Phytophthora resistance was assessed by measuring the size increase of a lesion at five (DL5)and ten days (DL10) after pod inoculation.
Six different QTL were detected in the F1 and BC1 populations. One QTL was found in both populations, and appeared to be a major component of disease resistance, and explaining
nearly 48% of the phenotypic variance in the F1 population. The absence of some yield QTL detection in the BC1 in comparison with the F1 population is due to the lack of transmission of the favouring alleles for these QTL from the single F1 tree used for the backcross. The phenotypic variance explained by the action of the quantitative trait alleles indicated
that genetic factors of both major and minor effects were involved in the control of the character studied. QTL conferring
increased resistance to Phytophthorawere identified in both susceptible parents, suggesting the presence of transgressive traits and the possibility of selection
in cacao. Pleiotropic and epistatic effects for the QTL were also detected. Finally, the use of marker assisted selection
(MAS) in cacao breeding programs is discussed.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
11.
Introgression libraries can be used to localize genomic regions carrying quantitative trait loci (QTL). We used this approach to detect QTL regions affecting the per se performance of agronomic and quality traits with two rye (Secale cereale L.) introgression libraries. Our objectives were to detect candidate introgression lines (pre‐ILs) that have a different per se performance than the recurrent parent and to identify the underlying QTL regions. The introgression libraries containing 40 BC2S3 lines each were established with marker‐assisted backcrossing from crosses of the heterozygous Iranian primitive rye accession Altevogt 14160 and the elite inbred line L2053‐N. To assess the phenotypic effect of the donor chromosome segments (DCS) the pre‐ILs were evaluated for grain yield, plant height, thousand‐kernel weight, test weight, falling number and protein content in replicated field trials at five locations in Germany over 2 years. In total, 58 significant (P < 0.05) differences between pre‐ILs and L2053‐N were observed in each introgression library. The DCS in pre‐ILs differing from the recurrent parent possess most likely the responsible QTL. Genomic regions carrying favourable QTL alleles were detected for test weight, thousand‐kernel weight and protein content. We conclude that Altevogt 14160 can not only be used to enrich the genetic variation of the restricted hybrid rye gene pools but will also allow the breeder to efficiently detect favourable QTL for marker‐assisted selection. 相似文献
12.
Identification of salt tolerance‐improving quantitative trait loci alleles from a salt‐susceptible rice breeding line by introgression breeding
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Xianjin Qiu Zhihua Yuan Huan Liu Xiaojiao Xiang Longwei Yang Wenjing He Bin Du Guoyou Ye Jianlong Xu Danying Xing 《Plant Breeding》2015,134(6):653-660
To improve salt tolerance of two elite rice varieties, Ce258 and Zhongguangxiang1 (ZGX1), two sets of introgression lines (ILs) each comprising 200 BC1F10 lines derived from a common donor, IR75862, and two recipient parents, Ce258 and ZGX1, were used for mapping of QTLs for four salt tolerance‐related traits at the seedling stage. Although the three parents were susceptible to salt, the two IL populations showed transgressive segregations for salt tolerance with 12 and 8 salt tolerance ILs in the Ce258‐ILs and ZGX1‐ILs. Eighteen main‐effect QTLs were identified for the four traits in the two IL populations, and the IR75862 alleles at most loci showed increased and decreased salt tolerance in the ZGX1 and Ce258 backgrounds, suggesting overwhelming genetic background effects on QTL detection for salt tolerance. The qDSS11 simultaneously detected in the two backgrounds was validated in a F2 population derived from a salt tolerance line and ZGX1. Our results indicated that salt tolerance‐enhancing allele could be identified in the elite susceptible breeding lines and that introgression of the favourable alleles could facilitate the development of superior lines with greater salt tolerance levels. 相似文献
13.
Feng-Xue Jin Dong-Min Kim Hong-Guang Ju Sang-Nag Ahn 《Journal of Crop Science and Biotechnology》2009,12(1):9-15
An advanced backcross line, HR9118, was produced from a single plant of BC2F3 families derived from a cross between Oryza rufipogon Griff. (IRGC 105491) as a donor parent and the O. sativa subsp. japonica cv. Hwaseongbyeo as a recurrent parent. Although HR9118 resembled Hwaseongbyeo, several traits were different from those
of Hwasoengbyeo, including days to heading, plant height, and awn. These differences between Hwasongbyeo and HR9118 could
be attributed to introgressed O. rufipogon chromosome segments into HR9118. Introgression analysis using 460 SSR markers revealed that three O. rufipogon-specific chromosome segments were detected in HR9118 genome. F2:3 populations derived from the cross between Hwaseongbyo and HR9118, consisting of 340 F2 plants and 137 F3 lines, were used to map and characterize QTLs for 12 traits. QTL analysis identified a total of 17 QTLs in the F2:3 populations. Of these, seven QTLs were shared by the F2 and F3 populations, whereas the other ten QTLs were identified only in the F3 population. In seven (41.2%) QTLs identified in this study, the O. rufipogon-derived alleles contributed desirable agronomic effects despite the overall undesirable characteristics of the wild phenotype.
Each of three O. rufipogon introgressed segments contained multiple QTLs, indicating linkage and/or pleotropic effects. A cluster of eight QTLs was
detected on chromosome 8 including a major QTL for awn. Substitution mapping using F2 population indicated that awn8 was located within an interval between two SSR makers RM23326 and RM23356 which are 590 kb apart. SSR markers tightly linked
to QTLs for yield components detected in this study will facilitate cloning of the gene underlying this QTL as well as marker-assisted
selection for variation in grain weight in an applied breeding program. 相似文献
14.
Construction and characterization of 3-S Lines, an alternative population for mapping studies in rice (Oryza sativa L.) 总被引:1,自引:0,他引:1
Most traits of agronomic importance in rice are quantitative in nature and are controlled by polygenes, called quantitative
trait loci (QTL). Understanding the nature and effect of QTLs are important for rice breeding to achieve higher yield and
stability. Single segment substitution lines (SSSLs or 3-S Lines) were developed through simple sequence repeats (SSR) marker-facilitated
backcrossing methods for Hua-Jing-Xian 74 (HJX74) with the donor segment from six elite germplasm and was characterized. Complete
genome survey was carried out with 258 polymorphic SSR markers. Polymorphism of the donors with the recurrent parent varied
between 32.98 and 60.73% with an average of 47.81%. Japonica donors were more polymorphic than indica donors. Number of substitution segments per plant decreased with the advancement of backcross generations. In BC2F1, BC3F1, BC3F2 and BC3F3 the average number of substitution segment per plant were 12.5, 5.98, 1.69 and 1.46, respectively. Average size of substitution
segments also decreased with the number of times plants were backcrossed and selfed. In BC2F1, BC3F1, BC3F2 and BC3F3, average size of the segments was 25.43, 22.38, 20.78 and 18.15 cM, respectively. The rate of reduction of segment size was
more in backcross (11.99%) than selfing (7.15%) generations. Percent recovery of recurrent parent genome in BC2F1, BC3F1, BC3F2 and BC3F3 was 82.24, 92.55, 98.04 and 98.52%, respectively. A total of 111 SSSLs comprising of 43 unique types were developed in BC3F2 and BC3F3. The estimated length of the segments in SSSLs ranged from 2.00 to 64.80 cM with an average of 21.75 cM, and 6.05 to 48.90 cM
with an average of 20.95 cM in BC3F2 and BC3F3, respectively. Total length of all substitution segments was 2367.5 cM that covered 704.50 cM (39.25%) of the entire rice
genome. Effective development and successful utilization of 3-S Lines for analysis of QTLs and mapping of genes established
the suitability of the SSR marker facilitated backcross breeding approach for 3-S Lines development and its utilization. 相似文献
15.
渐渗系IL6的遗传评价和渗入片段的鉴定 总被引:1,自引:1,他引:0
用海岛棉3-79的6号染色体渐渗系(简称IL6)和背景亲本TM-1构建了F2、F2:3群体,在2年的田间重复实验中调查了18个重要农艺性状,作遗传评价。并获得F2群体的分子数据,进行QTL定位和单标记分析。结果表明:亲本IL6中的渐渗片段,组成有3-79的6号染色体,3-79的非6号染色体和大部分的TM-1片段。IL6的产量、品质性状都优于受体亲本TM-1,遗传分析也发现产量、品质性状增效基因位点来自IL6,说明所渗入片段起着关键作用。亲本农艺性状表现和遗传分析结果表明,IL6渗入片段含有总铃数、单株铃数、衣分、果枝数、比强度、麦克隆值等性状的主基因。而QTL定位和单标记分析结果显示,IL6渗入片段含有单株铃数、衣分、果枝数、株高、子指、整齐度等性状的QTLs。 相似文献
16.
Hari S. Gupta Babu Raman Pawan K. Agrawal Vinay Mahajan Firoz Hossain Nepolean Thirunavukkarasu 《Plant Breeding》2013,132(1):77-82
Vivek Maize Hybrid 9‐ a popular single‐cross hybrid developed by crossing CM 212 and CM 145 was released for commercial cultivation in India. The parental lines, being deficient in lysine and tryptophan, were selected for introgression of opaque‐2 allele using CML 180 and CML 170 as donor lines through marker‐assisted backcross breeding. The opaque‐2 homozygous recessive genotypes with >90% recovery of the recurrent parent genome were selected in BC2F2, and the seeds with <25% opaqueness in BC2F3 were forwarded for seed multiplication. Vivek Quality Protein Maize (QPM) 9, the improved QPM hybrid, showed 41% increase in tryptophan and 30% increase in lysine over the original hybrid. The grain yield of the improved hybrid was on par with the original hybrid. The newly improved QPM maize hybrid released in 2008 will help in reducing the protein malnutrition because its biological value is superior over the normal maize hybrids. This short duration QPM maize hybrid has been adopted in several hill states of North Western and North Eastern Himalayan regions. 相似文献
17.
利用染色体片段代换系定位陆地棉株高QTL 总被引:4,自引:0,他引:4
以陆地棉中棉所36为轮回亲本和海岛棉海1为供体亲本, 构建染色体片段代换系。为了能检测到稳定的株高QTL,将三个代换系群体(BC5F3, BC5F3:4和BC5F3:5)在5个环境中种植,2009年和2010年分别在河南安阳种植BC5F3单株、BC5F3:4株行, 2011年分别在河南安阳、辽宁辽阳和新疆石河子种植BC5F3:4株系。结果表明,在不同群体环境中株高的超亲比例为53.43%~88.97%。从早期构建的总图距为5088.28 cM, 含有2280个SSR标记位点,覆盖26条染色体的遗传连锁图谱中筛选标记,对408个单株进行的SSR鉴定,结果检测到16个株高QTL,分布在10条染色体上。单个QTL解释的表型变异为7.35%~13.17%。有7个QTL在2个以上环境被检测到。与标记MUSS563紧密连锁的qPH-15-19在一个环境中被检测到,在前人的研究中也有报道。这些结果为进一步精细定位QTL、基因克隆、分子辅助选择等研究奠定基础。 相似文献
18.
Comparing mating designs to restore seed production of interspecific hybrids between Trifolium repens (white clover) and Trifolium uniflorum
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Muhammad Naeem Isabelle Marjorie Verry Peter D. Kemp James P. Millner Warren Mervyn Williams 《Plant Breeding》2017,136(3):420-426
Interspecific hybrids between Trifolium uniflorum and cultivated white clover (Trifolium repens) have highly useful characteristics for temperate pastoral systems derived from both parent species. However, the early hybrids (F1 and BC1) also have unacceptably poor seed production for commerce. This study analysed the basis for the poor seed production and investigated breeding strategies for overcoming the problem. The BC1F1 generation produced lower‐than‐expected numbers of heads per plant and seeds per floret. Backcrossing of selected hybrids to white clover corrected these deficiencies and created new variation. Seed numbers were also returned to near target levels by recurrent selection within the BC1 generation. Thus, it was possible to retain a theoretical average of 25% of T. uniflorum genome and still achieve high seed production per plant. The BC1F2 and BC2F1 generations produced high seed numbers per plant, along with reasonable variation. Both of these second‐generation hybrid forms have high reproductive potential and should be the focus for the selection of the desired combinations of agronomic and seed production traits. 相似文献
19.
Lijun Meng Xiuyun Lin Jinming Wang Kai Chen Yanru Cui Jianlong Xu Zhikang Li 《Plant Breeding》2013,132(6):604-612
To combine high yield and improved cold tolerance (CT) in a japonica rice variety, ‘Chaoyou1’ (CY1), 324 BC2F5 introgression lines (ILs) selected for CT from 11 CY1 BC2F4 populations were evaluated in replicated experiments for their CT at the reproductive and seedling stages. A mean realized heritability of 0.747 was achieved in this study for CT. Evaluation of 116 ILs from five BC populations in replicated experiments under stress and normal conditions identified 18 promising ILs that had greatly improved CT and yield compared with CY1. Detailed comparisons between the ILs and CY1 for CT and yield‐related traits under stress and non‐stress conditions provided useful information and better understanding of important issues such as donor selection, selection efficiency and associated changes in non‐target traits in the BC breeding process. The large numbers of CT ILs developed provide useful materials for genetic, physiological and molecular dissection of CT and yield traits using DNA markers and ‐omic tools, and as parents for further improving these traits by designed QTL pyramiding. 相似文献
20.
Identifying QTL for fiber quality traits with three upland cotton (Gossypium hirsutum L.) populations 总被引:2,自引:0,他引:2
Qianshun Shao Fengjiao Zhang Shiyi Tang Yong Liu Xiaomei Fang Dexin Liu Dajun Liu Jian Zhang Zhonghua Teng Andrew H. Paterson Zhengsheng Zhang 《Euphytica》2014,198(1):43-58
Cotton fiber quality was quantitative trait, controlled by multiple genes. Identification of stable quantitative trait loci (QTL) effectively contributing to favorable fiber quality traits would provide the key basis for marker-assisted selection used in molecular breeding projects. Three upland cotton F2 populations were established with a common parent Chinese cultivar Yumian 1 and three American commercial cultivars/lines (Acala Maxxa, CA3084 and TAM94L-25), each of which had unique fiber quality characteristic that was favorable economically. Three whole genome genetic maps were constructed with 323, 302 and 262 SSR loci for population (Yumian 1 × Acala Maxxa), (Yumian 1 × CA3084), and (Yumian 1 × TAM 94L-25) respectively, spanning 1,617.2, 1,639.9 and 1,441.4 cM. Based on these genetic maps and three generation phenotypic data of fiber quality traits (F2, F2:3 and F2:4), 77 QTL were detected, including 19 for fiber length, 14 for fiber uniformity, 17 for micronaire, 10 for fiber elongation, and 17 for fiber strength. Among these QTL, 46 QTL were significant QTL and 31 were putative QTL, including that one QTL (qFL05.1) and four QTL (qFL23.1, qFM06.1, qFM06.2 and qFE25.1) were detected across three and two populations respectively; two QTL qFL10.1 (Yumian 1 × TAM 94L-25) and qFL15.1 (Yumian 1 × Acala Maxxa) were detected in three generations; qFM23.1, qFE18.1 and qFS21.2 detected in population (Yumian 1 × CA3084), qFE10.1, and qFS10.2 detected in population (Yumian 1 × TAM 94L-25), and qFS15.1 detected in population (Yumian 1 × Acala Maxxa), were all detected in two generations. Alleles underlying these stable QTL were valuable candidate gene for fine mapping, cloning, and favorable gene pyramiding projects. Our study also verified that QTL mapping of fiber quality traits using multiple populations with a common parent had higher efficiency compared to single population crossed with two parents and favorable alleles contributed to QTL effect could be conferred by parents with inferior fiber quality traits. 相似文献