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991.
992.
Sergio Lanteri Ezio Portis Alberto Acquadro Rosario P. Mauro Giovanni Mauromicale 《Euphytica》2012,184(3):311-321
The species Cynara cardunculus includes the globe artichoke (var. scolymus), the cultivated cardoon (var. altilis) and the wild cardoon (var. sylvestris). The three taxa are sexually compatible and originate fertile F
1 progenies, which, given the high heterozygosity of the species, are highly segregating. We report the characterization of
two F
1 populations, one bred from a cross between globe artichoke and cultivated cardoon, and the other between globe artichoke
and wild cardoon. Both populations featured a wide array of phenotypes in relation to several traits, and some of the newly
developed genotypes are of interest for the ornamental market. The two populations were genotyped at 50 microsatellite (SSR)
loci: in the globe artichoke × wild cardoon and globe artichoke × cultivated cardoon progenies 116 and 97 alleles were respectively
detected. SSR pattern scores were used to produce an UPGMA dendrogram and a PCoA plot. A set of nine SSR loci, evenly dispersed
across the genome, was shown to be sufficient to unambiguously identify each segregant. The molecular fingerprinting is useful
for establishing the true to type correspondence of propagative materials in nurseries and ensures the effective correspondence
between the real and the declared identity of a clone. 相似文献
993.
Ploidy manipulations and interspecific crosses have allowed considerable genetic progress in Musa breeding, but estimation
of genetic parameters for parental selection remains a major challenge. This study aimed to determine the components of genetic
variance and the relative contribution of genetic effects to phenotypic variation of yield and phenological traits in secondary
triploid hybrids from tetraploid–diploid crosses. The hybrids were evaluated in two consecutive growth cycles on a tropical
forest site. Non-genetic effects accounted for a large fraction of the variation observed for most traits, except bunch weight.
Partitioning of genetic variance into additive and dominance components confirmed the predominant role of additive genetic
effects on the expression of bunch weight, fruit filling time, fruit length, plant height, and number of leaves while primarily
non-additive effects accounted for suckering behavior and fruit circumference. Maternal general combining ability (GCA) effects
accounted for the additive genetic variation in plant height and number of leaves, suggesting that selection for these traits
should be carried out in tetraploid clones. Conversely, paternal GCA effects were the primary causes of genetic variation
for fruit filling time, bunch weight, and fruit length, suggesting that these characters should be selected for in diploid
clones. Specific combining ability (SCA) effects were observed for all traits, except fruit filling time, suggesting that
additional genetic gain could be achieved through recombinative heterosis for these traits. 相似文献
994.
Zhenchang Liang Min Sang Benhong Wu Aihong Ma Shengjian Zhao Gan-Yuan Zhong Shaohua Li 《Euphytica》2012,186(2):343-356
Variation patterns and inheritance of anthocyanin content in the ripe berries of a tetraploid × diploid table grape cross population were investigated in two successive years. The population segregated for three different ploid levels: dipolids, triploids, and tetraploids. A total of 28 different anthocyanins were detected and quantified in the progeny population. Transgressive segregation for the total anthocyanin content was observed in all the three ploid progeny populations. The total anthocyanin content increased as the ploid level increased. The broad sense heritabilities (H2) of the total anthocyanin content were all relatively high, ranging from 0.53 to 0.98, 0.57 to 0.97 and 0.43 to 0.94 in the diploid, triploid and tetraploid population, respectively. Our results suggested that the total anthocyanin content followed an additive inheritance model in this polyploid segregation population. We also observed that the relative contribution of individual anthocyanins to the total anthocyanin content varied significantly among different ploid populations, suggesting that genetic background has important impact on the accumulation of the individual anthocyanin compounds. These results will help develop better breeding strategies in a polyploid table grape breeding program for improving the content of anthocyanins, an important class of polyphenolics possessing antioxidant activities and many other health-related benefits. 相似文献
995.
Varietal seed mixtures tend to increase and stabilize crop yields, yet their application is sparse. Large-scale cultivation of variety mixtures may require a better understanding of how inter-varietal interactions and their interaction with the environment may influence the grain yield of variety mixtures relative to their component varieties. For this purpose, six variety mixtures of spring barley and 14 component varieties were grown in each of 17 trial environments. A total of 28 observed and a priori plant characteristics, including grain yield, disease severity and weed competitiveness, were derived for each component variety in each trial. The relationship between inter-varietal diversity of each characteristic and the mixing effect on grain yield was analysed. Additionally, various types of yield stability were estimated and compared among mixtures and component varieties. One mixture out-yielded all of its component varieties in almost half of the trial environments. Inter-varietal diversity in grain yield potential correlated significantly with mixing effect, as did straw length diversity when weighted with weed pressure. The grain yields of most mixtures were more stable across environments than their component varieties when accounting also for the general response to environmental productivity. Hence, most mixtures adapted slightly better to environmental productivity and were less sensitive to environmental stress than their component varieties. We conclude that the efficacy of variety mixtures may be enhanced by mixing relatively high-yielding varieties differing in responsiveness to environmental productivity. 相似文献
996.
S. Gandhi Doss S. P. Chakraborti S. Roychowdhuri N. K. Das K. Vijayan P. D. Ghosh 《Euphytica》2012,185(2):215-225
Sericulture is an agro-based industry, which heavily depends on mulberry (Morus spp.) for its sustainability, as mulberry leaf is the only available feed for the silkworm Bombyx mori L. Sericulture, in West Bengal and other subtropical regions in India, suffers from lack of adequate quantity of quality
mulberry leaf during the colder months, the best season for rearing the high yielding bivoltine silkworm hybrids. In order
to develop mulberry varieties, which can sustain normal growth during these colder months to yield better, efforts have been
made in different research institutes in India. The present report is part of such an effort in which accessions in germplasm
bank were screened for better growth, leaf retention and leaf yield contributing associated traits. Twenty three selected
parents were crossed, 3,500 seeds were sown, 2,700 seedlings were transplanted to progeny row trail, selected 210 hybrids
were evaluated under primary yield trial and finally nine hybrids along with a control variety were studied in detail for
all leaf yield contributing traits under final yield trial. Stability analysis was adopted to identify hybrids, which can
yield stably across seasons. The hybrids CT-44 and CT-11 out yielding the control by 17.17 and 7.11% were selected as these
hybrids yield 7.93 and 8.15 mt/ha leaf respectively during the colder months (February) for their direct use as cultivars
in West Bengal and other subtropical areas of India to sustain bivoltine sericulture to produce quality and gradable silk
fibers. 相似文献
997.
Chromosome duplication—autopolyploidization—may affect plant morphology and breeding systems, ultimately enabling the production
of improved genotypes. In this study, the autotetraploid lines obtained from the self-incompatible diploid Hylocereus monacanthus and the autooctapolyploid lines obtained from the self-compatible tetraploid H. megalanthus were studied and compared with the donor accessions. The resulting H. monacanthus autotetraploids exhibit lower fruit weight, seed number, and pollen viability than the donor plant, but it has larger pollen
grains. Although the resulting H. megalanthus autooctaploids had larger pollen grains and lower pollen viability compared with the donor plant, only aborted fruits were
obtained from these lines. The most valuable change observed was the breakdown of the self-incompatibility system in the H. monacanthus autotetraploid lines. This research provides important information on the horticultural value of vine cacti autopolyploid
lines. 相似文献
998.
Jiwen Yu Shuxun Yu Shuli Fan Meizhen Song Honghong Zhai Xingli Li Jinfa Zhang 《Euphytica》2012,187(2):191-201
Cotton is one of the most important oil-producing crops and the cottonseed meal provides important protein nutrients as animal feed. However, information on the genetic basis of cottonseed oil and protein contents is lacking. A backcross inbred line (BIL) population from a cross between Gossypium hirsutum as the recurrent parent and G. barbadense was used to identify quantitative trait loci (QTLs) for cottonseed oil, protein, and gossypol contents. The BIL population of 146 lines together with the two parental lines was tested in the same location for three years in China. Based on a genetic map of 392 SSR markers and a total genetic distance of 2,895.2 cM, 17 QTLs on 12 chromosomes for oil content, 22 QTLs on 12 chromosomes for protein content and three QTLs on two chromosomes for gossypol content were detected. Seed oil content was significantly and negatively correlated with seed protein content, which can be explained by eight QTLs for both oil and protein contents co-localized in the same regions but with opposite additive effects. This research represents the first report using a permanent advanced backcross inbred population of an interspecific hybrid population to identify QTLs for seed quality traits in cotton in three environments. 相似文献
999.
Maraisa Crestani Solange Ferreira da Silveira Silveira Elisane Weber Tessmann Itamara Mezzalira Henrique de Souza Luche José Antonio Gonzalez da Silva Luiz Carlos Gutkoski Fernando Irajá Félix de Carvalho Antonio Costa de Oliveira 《Euphytica》2012,185(1):139-156
There has been a strong demand for oat genotypes that contain caryopsis with high chemical quality which can suit the different market niches. Therefore, the objectives of this study were to assess the general (GCA) and specific combining ability (SCA) of white oat cultivars through diallelic crosses providing information about the genetic effects on expression of grain chemical quality components. Also, it was aimed to estimate the heterosis on F1 and F2 generations and the vigor loss due to inbreeding. During 2008, 21 hybrid populations F1 and F2 were obtained from artificial crossing among seven Brazilian white oat cultivars, following the complete diallel design, without considering the reciprocals. These populations and their parents were evaluated in the 2009 season in the experimental field in Capão do Leão, RS, Brazil. The higher values of mean squares associated to GCA indicates a strong contribution of additive genetic effects to the expression of grain chemical components. The parents tested showed a tendency to develop progeny with negative heterosis regarding protein, lipid, β-glucan and soluble dietary fiber in the grain, and positive for the content of nitrogen-free extract, total and insoluble dietary fiber. IAC 7 features a potential parent for obtaining grains with high protein and dietary fiber content, and low caloric content, fit to human diet. Meanwhile, UPF 15 and FAPA Louise can represent donors of alleles to increase lipid contents, while FAPA Louise and URS Guapa can be used to raise the grain nitrogen-free extract contents of lines intended for animal feeding. 相似文献
1000.
Grzegorz Bartoszewski Cezary Waszczak Piotr Gawroński Iwona Stępień Hanna Bolibok-Brągoszewska Alain Palloix Véronique Lefebvre Aleksandra Korzeniewska Katarzyna Niemirowicz-Szczytt 《Euphytica》2012,186(2):453-461
The nuclear male sterility gene ms8 is expected to facilitate the production of sweet pepper (Capsicum annuum L.) hybrids as it provides means for hybridization without the labor-intensive hand emasculation of female inbred lines.
The development of molecular markers linked to ms8 locus will help the breeding practice for the selection of hybrid parental lines. In this study, F2 population resulting from a cross between the sweet pepper male sterile line 320 and the male fertile variety Elf was used
to identify DNA markers linked to the ms8 locus. With the use of RAPD–BSA technique, seven markers linked to the ms8 locus were found. Four of them were converted into SCAR markers. In addition, two COSII/CAPS markers linked to the ms8 locus were identified. Comparative mapping with reference pepper maps indicated that the ms8 locus is located on the lower arm of the pepper chromosome P4. Identified markers are useful for molecular breeding, however,
at present markers tightly linked to ms8 locus are still lacking. Identification of molecular markers linked to the ms8 locus and determination of its chromosomal localization are useful for fine mapping and also provide the perspective for
ms8 gene cloning. 相似文献