共查询到20条相似文献，搜索用时 31 毫秒
1.
Tariq Mahmood Muhammad H. Rahman Gary R. Stringam Francis Yeh Allen Good 《Euphytica》2005,144(1-2):157-167
A population of 112 F1-derived doubled haploid lines was produced from a reciprocal cross of Brassica juncea. The parents differed for seed quality, seed color and many agronomic traits. A detailed RFLP linkage map of this population,
comprising 316 loci, had been constructed, and was used to map quantitative trait loci (QTL) for seed yield and yield components,
viz. siliqua length, number of seeds per siliqua, number of siliques per main raceme and 1000-seed weight. Stable and significant
QTLs were identified for all these yield components except seed yield. For yield components, a selection index based on combined
phenotypic and molecular data (QTL effects) could double up the efficiency of selection compared to the expected genetic advance
by phenotypic selection. Selection indices for high seed yield, based on the phenotypic data of yield and yield components,
could only improve the efficiency of selection by 4% of the genetic advance that can be expected from direct phenotypic selection
for yield alone. Inclusion of molecular data together with the phenotypic data of yield components in the selection indices
did not improve the efficiency of selection for higher seed yield. This is probably due to often negative relationships among
the yield components. Most of the QTLs for yield components were compensating each other, probably due to linkage, pleiotropy
or developmentally induced relationships among them. The breeding strategy for B. juncea and challenges to marker assisted selection are discussed. 相似文献
2.
B. Tar'an T. Warkentin D.J. Somers D. Miranda A. Vandenberg S. Blade D. Bing 《Euphytica》2004,136(3):297-306
Breeding efforts to improve grain yield, seed protein concentration and early maturity in pea (Pisum sativum L.) have proven to be difficult. The use of molecular markers will improve our understanding of the genetic factors conditioning these traits and is expected to assist in selection of superior genotypes. This study was conducted to identify genetic loci associated with grain yield, seed protein concentration and early maturity in pea. A population of 88 recombinant inbred lines (RILs) that was developed from a cross between 'Carneval' and 'MP1401' was evaluated at 13 environments across the provinces of Alberta, Manitoba and Saskatchewan, Canada in 1998, 1999 and 2000. A linkage map consisting of 193 AFLPs (amplified fragment length polymorphism), 13 RAPDs (random amplified polymorphic DNA) and one STS (sequence tagged site) marker was used to identify putative quantitative trait loci (QTL) for grain yield, seed protein concentration and early maturity. Four QTL were identified each for grain yield and days to maturity, and three QTL were identified for seed protein concentration. A multiple QTL model for each trait showed that these genomic regions accounted for 39%, 45% and 35% of the total phenotypic variation for grain yield, seed protein concentration and days to maturity, respectively. The consistency of these QTL across environments and their potential for marker-assisted selection are discussed in this report. 相似文献
3.
4.
Stephen Byrne Emma Guiney Susanne Barth Iain Donnison Luis A. J. Mur Dan Milbourne 《Euphytica》2009,166(1):61-70
Flowering time is a trait which has a major influence on the quality of forage. In addition, flowering and subsequent seed
yields are important traits for seed production by grass breeders. In this study, we have identified quantitative trait loci
(QTL) for flowering time and morphological traits of the flowering head in an F1 mapping population in Lolium perenne L (perennial ryegrass), a number of which have not previously been identified in L. perenne mapping studies. QTL for days to heading (DTH) were mapped in both outdoor and glasshouse experiments, revealing three and
five QTL for DTH which explained 53% and 42% of the total phenotypic variation observed, respectively. Two QTL for DTH were
detected in both environments, although they had contrasting relative magnitudes in each environment. One QTL for spike length
and three QTL for spikelets per spike were also identified explaining, a total of 32 and 33% of the phenotypic variance, respectively.
Furthermore, the QTL for spike length and spikelets per spike generally coincided with QTL for days to heading, implying co-ordinate
regulation by underlying genes. Of particular interest was a region harbouring overlapping QTL for days to heading, spike
length and spikelets per spike on the top of linkage group 4, containing the major QTL for spike length identified in this
population. 相似文献
5.
Summary The expected improvement in grain yield if selection was made for plant characters measured between flowering and maturity was evaluated in populations of rapeseed (Brassica campestris and B. napus) grown in a droughted environment. Drought was commenced at flowering in each species and measurements were made on plants at the commencement of the drought stress, during the stress treatment and at crop maturity.Substantial genetic and phenotypic variation was observed in yield as well as the different morphophysiological determinants of yield. In B. campestris no single parameter was found to be a suitable alternative selection criterion to yield since the correlated responses in yield if selection was for another character was lower than if selection was for yield alone. By the use of a selection index however, joint selection for yield, as well as harvest index, 1000 seed weight and seeds per pod, was expected to be 20% more effective than direct selection for yield under drought. In the B. napus population direct selection for flowering time or for harvest index was predicted to result in a genetic advance in yield equal to or greater than that obtained by direct selection for yield, whereas joint selection for flowering time and yield should result in a 16% greater yield increase. Selection for increased yield in these populations grown in droughted conditions is discussed. 相似文献
6.
Lianguang Shang Fang Liu Yumei Wang Abdugheni Abduweli Shihu Cai Kunbo Wang Jinping Hua 《Plant Breeding》2015,134(6):703-712
Plant height served as one of model traits to analyse dynamic development. The objective of this research was to investigate quantitative trait loci (QTL) and dynamic QTL for plant height trait using an intraspecific recombinant inbred line (RIL) population and a constructed genetic map in Upland cotton (Gossypium hirsutum L.). Totally, 41 QTL and 23 conditional QTL controlling plant height were detected at two experimental environments, respectively. Four stable QTL were identified simultaneously in both environments. Some QTL identified at the early stage could not be detected at the final stage at plant maturity. Conditional QTL with different genetic effects were identified at certain stages, demonstrating that the expression of QTL had temporal characteristic during plant growth. Therefore, the study of dynamic QTL could unravel temporal genetic patterns controlling complex developmental quantitative traits. 相似文献
7.
唐山红小豆地方品种资源数量性状的遗传变异分析 总被引：1，自引：0，他引：1
以71份唐山红小豆地方品种资源为研究对像,对资源各数量性状的平均表现、遗传变异、遗传力及预期遗传进度进行了分析。结果表明,唐山红小豆地方品种资源生育期类型单一、株型高大、产量性状较好,子粒大小中等;主茎分枝、单株荚数、单株生产力、小区产量、生育前期、百粒重、单荚粒数具有中等以上的遗传变异系数和遗传进度,对其选择有一定的效果;在选择效果明显的性状中,生育期、百粒重、主茎分枝遗传力较高,可在早代选择;小区产量遗传力中等,可在遗传基础相对稳定的较高世代选择;而株高、单株荚数、单荚粒数、单株生产力的遗传力较低,应在遗传基础纯合稳定的高世代选择。 相似文献
8.
Summary Two hundred genotypes of Coriandrum sativum L. exhibited genetic variation for plant height, primary and effective branches, days to flowering and maturity, umbels and umbellets per plant, grains per umbellet, thousand seed weight, straw yield and grain yield per plant and harvest index. Heritability estimates were high for days to flowering, thousand seed weight and days to maturity; moderate for plant height, straw yield, umbels per plant, umbellets per plant and number of primary branches; and low for harvest index, effective branches, grain yield per plant and grains per umbellet. Phenotypic correlations of grain yield per plant were highly significant and positive with umbellets per plant, umbels per plant, number of effective branches, straw yield per plant, number of primary branches, plant height, number of grains per umbellet and harvest index. Maximum direct contribution to grain yield per plant was made by umbellets per plant, followed by straw yield per plant, umbels per plant and grains per umbellet. Umbellets per plant made sizeable indirect effect via straw yield per plant. Straw yield per plant made sizeable indirect contribution via umbellets per plant. 相似文献
9.
The improvement of energy efficiency in the greenhouse production of cut rose and pot rose can be achieved through the use
of rose cultivars having vigorous growth. A better understanding of the inheritance of vigour and its related traits will
assist the breeding activities. Quantitative trait locus (QTL) analyses were performed with the help of an integrated linkage
map of a diploid rose population originating from a cross between Rosa multiflora-derived genotypes. The underlying datasets for ten vigour-related traits were collected in an evaluation study of this population
in two greenhouse experiments with suboptimal temperatures for growth. We identified ten chromosomal regions, scattered over
the seven linkage groups, containing QTLs for these traits. Considering each trait separately, we detected a total of 42 QTLs.
Among these QTLs, 24 were found in both of the experiments, eight and ten were specific to either of the two experiments.
The number of QTLs for individual traits varied from three to five with a respective contribution to the phenotypic variation
from 12 to 35%. QTLs for highly correlated traits frequently co-localized, indicating a common genetic basis. Clustering of
QTLs for different traits was noted in some chromosome regions, for instance, one on chromosome 2 included major QTLs for
eight of ten traits under study, suggesting co-localization of several separate genes or/and the occurrence of various genes
having pleiotropic effects. The discovery of markers associated to QTL regions is in roses the first step towards marker-assisted
selection for vigour improvement enabling the transfer of useful QTL-alleles of R. multiflora to pot and cut roses. 相似文献
10.
A diverse panel of 96 genotypes of lentil was used in this study to identify QTL for nine agronomic traits through marker-trait association analysis. This study showed significant genetic variability among the lentil genotypes for nine agronomic traits and had medium to large broad sense heritability estimates (h2 =?0.58–0.95). Screening of 534 SSR markers resulted in 266 polymorphic loci that generated 697 alleles ranging from 2 to 16 alleles per locus across the genotypes. The model-based population structure analysis identified two distinct subpopulations among lentil genotypes and each subpopulation did not show any admixture. Marker trait association (MTA) analysis following ML model resulted in the identification of 24 MTAs for nine traits at P?<?0.01. The per cent of phenotypic variation explained by each associated marker with particular agronomic trait ranged from 7.3 to 25.8%. The highest proportion of total phenotypic variation (23.1–25.8%) was explained by the QTLs controlling the primary branches/per plant. In the present study, few EST-SSR markers showed significant association with days to maturity, pods/plant, secondary branches/plant, 100 seed weight, yield/plant and reproductive duration and explained large phenotypic variation (7.3–23.8%). Hence, these markers can be used as functional markers in lentil breeding program for developing improved cultivars. 相似文献
11.
Weixian Liu Moon Young Kim Kyujung Van Yeong-Ho Lee Hulin Li Xianhu Liu Suk-Ha Lee 《Journal of Crop Science and Biotechnology》2011,14(1):65-70
Two soybean recombinant inbred line populations, Jinpumkong 2 × SS2-2 (J × S) and Iksannamulkong × SS2-2 (I x S) showed population-specific
quantitative trait loci (QTLs) for days to flowering (DF) and days to maturity (DM) and these were closely correlated within
population. In the present study, we identified QTLs for six yield-related traits with simple sequence repeat markers, and
biological correlations between flowering traits and yield-related traits. The yield-related traits included plant height
(PH), node numbers of main stem (NNMS), pod numbers per plant (PNPP), seed numbers per pod (SNPP), 100-seed weight (SW), and
seed yield per plant (SYPP). Eighteen QTLs for six yield-related traits were detected on nine chromosomes (Chrs), containing
four QTLs for PH, two for NNMS, two for PNPP, three for SNPP, five for SW, and two for SYPP. Two highly significant QTLs for
PH and NNMS were identified on Chr 6 (LG C2) in both populations where the major flowering gene, E1, and two DF and DM QTLs were located. One other PNPP QTL was also located on this region, explaining 12.9% of phenotypic
variation. Other QTLs for yield-related traits showed population-specificity. Two significant SYPP QTLs potentially related
with QTLs for SNPP and PNPP were found on the same loci of Chrs 8 (Satt390) and 10 (Sat_108). Also, highly significant positive
phenotypic correlations (P < 0.01) were found between DF with PH, NNMS, PNPP, and SYPP in both populations, while flowering was negatively correlated
with SNPP and SW in the J × S (P < 0.05) and I × S (P < 0.01) populations. Similar results were also shown between DM and yield-related traits, except for one SW. These QTLs identified
may be useful for marker-assisted selection by soybean breeders. 相似文献
12.
Tissue culture-derived variation in crop improvement 总被引：30，自引：3，他引：30
S. Mohan Jain 《Euphytica》2001,118(2):153-166
Tissue culture generates a wide range of genetic variation in plant species which can be incorporated in plant breeding programmes.
By in vitro selection, mutants with useful agronomic traits, e.g. salt or drought tolerance or disease resistance, can be isolated in
a short duration. The successful use of somaclonal variation is very much dependent on its genetic stability in the subsequent
generations for which molecular markers such as RAPDs, AFLPs, SSRs and others can be helpful. The potential of somaclonal
variation has yet to be fully exploited by breeders, even though a few cultivars have been developed in crops such as Brassica juncea, rice and others.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
13.
Selection of oat genotypes combining earliness and short plant height could stimulate oat cultivation worldwide. However, the mechanisms involved with the genetic control of heading date and plant height traits are not fully understood to date. This study aimed to identify genomic regions controlling heading date and plant height in two hulled by naked oat populations and to compare these genomic regions with that of other grass species. Recombinant inbred lines of each population and their parents were genotyped by a 6 K BeadChip Illumina Infinium array and assessed for heading date and plant height in two sowing dates. The quantitative trait loci (QTL) affecting these traits were detected by simple interval mapping. The two oat populations showed different genetic mechanisms controlling heading date. A major QTL was identified in one of the populations, mapped into the ‘Mrg33’ consensus linkage group from the current oat map. Two other QTL were detected into the ‘Mrg02’ and ‘Mrg24’ groups, in the second population. On the other hand, both populations presented the same genomic region controlling plant height. Six SNP markers, mapping on the same linkage group within each population, were associated with the trait, regardless the sowing date, explaining more than 20% of the phenotypic variation. Five of these six markers were mapped into three different linkage groups on the oat consensus map. Genomic regions associated with heading date and plant height in oat seem to be conserved in Oryza sativa L. and Brachypodium distachyon. Our results provide valuable information for marker-assisted selection in oats, allowing selection for earliness and plant height on early segregating generations. 相似文献
14.
A 2-year study of autumn-sown white lupin (Lupinus albus L.) was conducted under rainfed Mediterranean conditions in southern Spain. 108 landraces were evaluated for yield and major
phonological and plant structural characteristics. Path coefficient and Genotype-Trait (GT) biplot analysis were used. Applying
both types of analyses to the multiple trait data revealed that GT biplot graphically displayed the interrelationships among
traits and facilitated visual comparison of accessions and selection. Wide variation was observed for trait phenology (dates
of flowering and maturity), plant structure (plant and first order inflorescence height) and yield characters (first order
branches, first order inflorescence and total yield). It was found that the accessions with the highest yields were the tallest
and the latest to flower, both on the mainstem and on the lowest first order branch, and also were the latest to mature. GT
biplots also had suggested as the accessions have been displayed according to their origins. The results showed that foreign
germplasm may be an important material for improving some yield components such as number of pods and seeds per plant of locally
adapted lupins in Spain.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
15.
Responses to divergent selection for cob color in maize 总被引：1，自引：1，他引：0
Previous studies showed that in materials derived from maize (Zea mays L.) single cross A632 × Mu195 there is association between agronomic traits and cob color (affected by P1 gene). Objectives of this study were to evaluate the responses to divergent selection for cob color in F2-Syn 0 (obtained by selfing A632 × Mu195), estimate the genetic parameters of the involved putative quantitative trait loci
(QTL), and evaluate the responses to divergent selection for cob color in A632 and Mu195 backgrounds. The populations selected
in F2-Syn 0 for red (R0) or white cob (W0) were tested in four trials. Differences between R0 and W0 were found for grain yield
(85.0 vs. 75.0 g/plant) and other traits; most of these differences were related to leaf number/plant. Then, population F2-Syn 1, derived after one random mating generation, was divergently selected for cob color, thus producing R1 and W1. Populations
R0, W0, R1, and W1 were tested in two trials, allowing the estimate of genetic effects and recombination frequencies for putative
QTL of several traits. Finally, a divergent selection for cob color was conducted in segregating materials of A632 and Mu195
backgrounds. The two pairs of selected populations were compared in two trials; the responses were similar to those detected
by comparing R0 and W0. We conclude that divergent selection for cob color in F2-Syn 0 is effective for several traits, that such responses are due to putative QTL linked to P1, and that selection is also effective in different genetic backgrounds. 相似文献
16.
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
17.
For a better understanding of the inheritance of seed yield traits in Quinoa (Chenopodium quinoa) Willd., a half-diallelic crossing experiment with six diverse but uniform breeding lines was conducted. True hybrid plants
were detected by means of differences in panicle colour in 14 out of the 15 crosses performed. The agronomic performance of
14 F2 populations and six parental lines was evaluated in field trials on fertile clay soil. General and specific combining ability
of the lines (GCA and SCA) were estimated. Highly significant differences in GCA effects were found between the lines for
plant height at maturity, early flowering, early maturity, seed yield and thousand seed weight. Significant SCA effects were
only found for plant height at maturity. However, SCA effects were rather small and accounted for 7% of the total variance.
The finding of large GCA effects and low SCA effects suggests that best selection results could be expected from crosses between
the agronomic best performing genotypes.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
18.
Association of isozyme markers with quantitative trait loci in random single seed descent derived lines of lentil (Lens culinaris Medik.) 总被引：1，自引：0，他引：1
Summary Polymorphism at isozyme loci was used to locate factors responsible for variation in quantitative traits of lentil. Eight sets of random single seed descent (RSSD) derived lines were developed by advancing individual F3 plants of interspecific (L. culinaris Medik. × L. orientalis Boiss.) hybrids to the F6. The RSSD lines in each of the eight sets differed for alleles at 2–8 isozyme loci. In each set, association of isozyme loci with variation in seven quantitative traits (days to flower, days to mature, plant height, biomass, seed yield, harvest index, seed weight) was determined for each pairwise combination of a quantitative trait with a marker locus. Loci affecting variation in all seven quantitative traits were detected by their association with 14 isozyme markers (Aat-c, Aat-m, Aat-p, Adh-1, Fk, Gal-1, Gal-2, Lap-1, Lap-2, Pgd-p, Pgi, Pgm-c, Pgm-p, Skdh). The known position of 10 the 14 isozyme loci on the lentil genetic map was used to mark the genomic regions for possible location of associated quantitative trait loci (QTL). Detected QTL were found to be located in six of the seven linkage groups on lentil genetic map. Regions of the genome represented by linkage groups, 1, 5 and 7 appeared to affect a greater number of traits than other genomic regions represented by linkage groups 2, 3 and 4. Results indicated that the mean expression of quantitative traits at segregating marker locus classes can be used to locate the genetic factors in lentil which influence the behavior of economically important traits. 相似文献
19.
S. Shanmugasundaram 《Euphytica》1979,28(2):495-507
Summary The photoperiodic response on 12 characters in 40 soybean, Glycine max (L.) Merrill, cultivars were investigated using 10-hour (short day) and 16-hour (long day) photoperiods. Seventeen cultivars showed no significant difference between photoperiods for all 12 characters. Seven cultivars showed significant difference for only one trait. Phenotypic changes in 17 cultivars may be due to factors other than photoperiod. Number of pods per plant, days to maturity, and number of nodes per plant were highly correlated with yield per plant in both photoperiods. Invariably, the cultivars which had significant differences in the numbers of flowers produced per plant between the two photoperiods also had significant differences in the numbers of pods per plant and yield. First node to flower, plant height at flowering, days to flowering, nodes at flowering, and the 100-seed weight were least influenced by the photoperiods in most of the cultivars, while the height at maturity, number of nodes at maturity, number of days to maturity, and yield were most influenced.AVRDC Journal paper 46 (78–88). 相似文献
20.
Interspecific hybridization is an important tool to elucidate intergenomic relationships, transfer characters across species and develop synthetic amphidiploids, and it has been widely applied for improving Brassicas. The objective of the present study was to create genetic variability in Brassica through interspecific hybridization. Crosses between Brassica juncea (AABB, 2n= 36), and Brassica rapa (AA, 2n = 20) vars toria, yellow sarson, and brown sarson were attempted, and the hybrid derivatives were advanced to the F4 generation. Hybrids were obtained from the crosses B. juncea× toria and B. juncea× yellow sarson. The F1 plants were vigorous and intermediate to the parents in many morphological traits. The meiotic study of AAB hybrids showed 10 II + 8 I in the majority (71.8%) of cells analysed. A maximum of 12 and a minimum of seven bivalents were also observed in a few cells. The occurrence of multivalent associations (trivalents to pentavalents) at diakinesis/metaphase I and a bridge‐fragment configuration at anaphase I were attributed to homoeology between A and B genomes. A high percentage of plants resembling B. juncea was observed in the F2 generation. Transgressive segregation in both directions was found for plant height, primary branches, main raceme length, siliquae on main raceme, siliqua intensity, seeds per siliqua and seed yield. There were significant differences for the 14 characters in the F4 derivatives. Moderate to high estimates of phenotypic and genotypic coefficients of variation, broad‐sense heritability, and expected genetic advance were found for seed yield, 1000‐seed weight, siliquae per plant, seeds per siliqua and days to flowering. Intergenomic recombination, reflected as wide variation in the hybrid progenies, permitted the selection of some useful derivatives. 相似文献