WorldWideScience

Sample records for hybrid sunflower species

  1. Genomic In Situ Hybridization (GISH) as a Tool to Identify Chromosomes of Parental Species in Sunflower Interspecific Hybrids

    Science.gov (United States)

    Interspecific hybridization has been widely used to transfer genes from wild species into cultivated sunflower. Fluorescent genomic in situ hybridization (GISH) has been used to identify alien chromosomes or segments in other crops, but an equivalent technique for sunflower is lacking. The objective...

  2. [Genotype peculiarities of crossability of cultivated sunflower with wild species and the use of embryo culture in interspecific hybridization].

    Science.gov (United States)

    Popov, V N; Iushkina, L L; Sharypina, Ia Iu; Kirichenko, V V

    2005-01-01

    Peculiarities of the genotype effect of cultivated and wild sunflower species on crossability indices and in vitro hybrid embryonic development have been investigated. It was shown that selection of initial material can considerably influence seed-setting and in vitro embryonic development in the cross group of cultivated sunflower with annual and perennial wild species. The range of plant hybrids obtained through somatic embryogenesis and induction of adventitious shoots was higher in comparison with direct growth of embryos in in vitro culture.

  3. Microsatellite signature of ecological selection for salt tolerance in a wild sunflower hybrid species, Helianthus paradoxus

    Science.gov (United States)

    EDELIST, CÉCILE; LEXER, CHRISTIAN; DILLMANN, CHRISTINE; SICARD, DELPHINE; RIESEBERG, LOREN H.

    2008-01-01

    The hybrid sunflower species Helianthus paradoxus inhabits sporadic salt marshes in New Mexico and southwest Texas, USA, whereas its parental species, Helianthus annuus and Helianthus petiolaris, are salt sensitive. Previous studies identified three genomic regions — survivorship quantitative trait loci (QTLs) — that were under strong selection in experimental hybrids transplanted into the natural habitat of H. paradoxus. Here we ask whether these same genomic regions experienced significant selection during the origin and evolution of the natural hybrid, H. paradoxus. This was accomplished by comparing the variability of microsatellites linked to the three survivorship QTLs with those from genomic regions that were neutral in the experimental hybrids. As predicted if one or more selective sweeps had occurred in these regions, microsatellites linked to the survivorship QTLs exhibited a significant reduction in diversity in populations of the natural hybrid species. In contrast, no difference in diversity levels was observed between the two microsatellite classes in parental populations. PMID:17107488

  4. Orfej: New NS sunflower hybrid

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    Cvejić Sandra

    2010-01-01

    Full Text Available New sunflower hybrid Orfej was developed by breeding process in the Institute of Field and Vegetable Crops, Novi Sad. Hybrid has high yield potential, excellent seed quality, adaptive to grown in different agro-ecological conditions and highly resistant and tolerant to main diseases and vermin in the region. Hybrid is resistant to all races of downy mildew (Plasmopara halstedii and highly tolerant to root and stem forms of white rot (Sclerotinia sclerotiorum. This work shows the results of seed yield from the trials of the Department for plant variety registration and protection and the results of Small plot trials of the Institute of Field and Vegetable Crops.

  5. Backcrosses in interspecific hybridization in sunflower

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    Atlagić Jovanka

    2003-01-01

    Full Text Available When incorporating desirable traits (resistance to causal agents of various diseases from the wild relatives into the cultivated sunflower, some undesirable ones are introduced too (branching, small head diameter, low oil content, etc. To overcome this problem, backcrosses (F1 interspecific hybrids x cultivated sunflower are used, although very often desirable traits are lost in the process. Cytological analysis (meiosis and pollen viability and molecular markers (RAPD were used to estimate what portion of the parental species genome was present in (be interspecific hybrids of the F1 and BC1F1 generations. The results showed that the percentage of irregularities at meiosis increased from F1 to BC1F1 gen. They also indicated the presence of aneuploids and sterility in the cross between the hexaploid species H.rigidus and cultivated sunflower. The genetic distance between the parents was 83%, that between H.rigidus and the F1 hybrid 54 61%, and that between H.annuus and F1 hybrid 70-76%. In the BC1F1 generation, the genetic distance from Hannuus decreased to 58-66% and that from H.rigidus increased to 69-76%.

  6. New confectionary sunflower hybrids in NS palette

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    Hladni Nada

    2011-01-01

    Full Text Available Sunflower breeding is directed towards the increase of the genetic potential for yield, stability of the yield, health care, and the quality of nutrition along with the increase of the production economy. In accordance with the Serbian market demands there have been efforts in breeding highly productive hybrids for special uses of the confectionary type at the Institute of Field and Vegetable Crops in Novi Sad. In this program, special attention has been given to the increase of the protein content and quality while decreasing the seed oil content, to the increase of 1000 seed weight and the decrease of the hull ratio. New NS confectionary hybrids NS-H-6316, NS-H-6318 and NS-H-6320 are adequate for nutrition, dehulling and core production. They belong to the group of mid-early hybrids while their genetic potential for seed yield is above 4.5 t ha-1 and seed oil content is less than 40%. Protein content in the core is 23-27%, mass of 1000 seeds is above 95 g, and the hull ratio is low. With the creation of the new palette of NS sunflower hybrids for various production purposes and conditions, we have gained higher quality material for the needs of the oil, food and baking industry.

  7. Characterization of the Bulgarian sunflower hybrid Valin

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    G. Georgiev

    2016-09-01

    Full Text Available Abstract. A male sterile two-linear sunflower hybrid was developed at Dobrudzha Agricultural Institute – General Toshevo using the method of inter-linear hybridization. The mother component is line 10517 which possesses cytoplasmic male sterility, and the father component is line 10595R, a fertility restorer of branched type. Both parental forms have very good general and specific combining ability. Hybrid Valin is medium early, with vegetation period of 110 – 115 days, plant height 165 – 175 cm and head diameter 17 – 18 cm. The percent of kernel in seed is within the range of 65 – 73%. Seeds have absolute weight 50 – 55 g, and oil content in seed is 46 – 50%. The hybrid is resistant to lodging and moderately resistant to phoma and phomopsis. The resistance to downy mildew is as high as 95 % up to race 700, and the resistance to the parasite Orobanche is 100% (races A-F. In the breeding fields of DAI the hybrid went through threeyear testing according to a scheme and growing technology approved for this crop. During the first two years of the control testing it exceeded the mean standard by seed yield with 11.0% and 14.4%, respectively. During the third year, hybrid Valin was above the mean standard with 10.9% by seed yield and with 6.6% by oil yield in a unified competitive varietal testing. The maximum yield obtained at DAI was 4483 kg/ha, and the maximum oil content was 50.1%. In 2007 and 2008 hybrid Valin went through official testing within the structure of the Executive Agency of Variety Testing, Field Inspection and Seed Control of Bulgaria. By the index seed yield, the exceeding of the mean standard was 23.6 % in the first year, and in the second the yield was with 1.4 % below the standard. Oil content was a little below the standard in both years. The aim of this investigation was to make as full as possible a characterization of the new registered sunflower hybrid Valin on the base of biological, phytopatological and

  8. Cytogenetic study of hexaploid species Helianthus tuberosus and its F1 and BC1F1 hybrids with cultivated sunflower, H. annuus

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    Atlagić Jovanka

    2006-01-01

    Full Text Available Helianthus tuberosus is a potential source of resistance to many disease-provoking pathogens. Three accessions of H. tuberosus were used in this research and they were crossed with cultivated sunflower. Six F] and two BC1F1 hybrid combinations were obtained. Analysis of meiosis was performed using aceto-carmine method (GEORGIEVA-TODOROVA, 1976 and pollen viability was determined by staining method of ALEXANDER (1969. Meiosis was regular in cultivated sunflower and the pollen viability was high (96.8-98.9%. Low percent of irregularities was found in the meiosis of H. tuberosus. Pollen viability was high (97.2-98.7%. Chromosome pairing was mostly regular in F1 hybrids (34 bivalents, but some meiocytes contained 28-32 bivalents with uni- and quadrivalents present. The percent of meiocytes with fast chromosomes in metaphase was 24.6-87.2, with lagging chromosomes in anaphase I 10.5-81.0 and in telophase 25.0-33.3. Chromosome bridges were detected in 0-9.9% of meiocytes in anaphase. Pollen viability in F1 hybrids ranged from 27.0 to 47.9%. In BC1F1 hybrids number of bivalents was 16-25, univalent 2-18 and multivalent 0-1. Although a triploid set of chromosomes (51 was expected in BC1F1 hybrids, number of chromosomes was 45-57. Pollen viability varied from 0 to 54.3%.

  9. Genomic Prediction of Sunflower Hybrids Oil Content

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    Brigitte Mangin

    2017-09-01

    Full Text Available Prediction of hybrid performance using incomplete factorial mating designs is widely used in breeding programs including different heterotic groups. Based on the general combining ability (GCA of the parents, predictions are accurate only if the genetic variance resulting from the specific combining ability is small and both parents have phenotyped descendants. Genomic selection (GS can predict performance using a model trained on both phenotyped and genotyped hybrids that do not necessarily include all hybrid parents. Therefore, GS could overcome the issue of unknown parent GCA. Here, we compared the accuracy of classical GCA-based and genomic predictions for oil content of sunflower seeds using several GS models. Our study involved 452 sunflower hybrids from an incomplete factorial design of 36 female and 36 male lines. Re-sequencing of parental lines allowed to identify 468,194 non-redundant SNPs and to infer the hybrid genotypes. Oil content was observed in a multi-environment trial (MET over 3 years, leading to nine different environments. We compared GCA-based model to different GS models including female and male genomic kinships with the addition of the female-by-male interaction genomic kinship, the use of functional knowledge as SNPs in genes of oil metabolic pathways, and with epistasis modeling. When both parents have descendants in the training set, the predictive ability was high even for GCA-based prediction, with an average MET value of 0.782. GS performed slightly better (+0.2%. Neither the inclusion of the female-by-male interaction, nor functional knowledge of oil metabolism, nor epistasis modeling improved the GS accuracy. GS greatly improved predictive ability when one or both parents were untested in the training set, increasing GCA-based predictive ability by 10.4% from 0.575 to 0.635 in the MET. In this scenario, performing GS only considering SNPs in oil metabolic pathways did not improve whole genome GS prediction but

  10. Development of sunflower hybrids tolerant to tribenuron methyl

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    Jocić Siniša

    2011-01-01

    Full Text Available Discovery of tribenuron-methyl resistant wild Helianthus annuus L. population (ANN-KAN created an opportunity for expansion of sunflower herbicide resistance breeding program. The aim of this study was development of sunflower hybrids resistant to tribenuron-methyl. Creation of tribenuron-methyl resistant hybrids would enable the use of a wider palette of herbicides for sunflower, more efficient chemical control of Cirsium arvense and more economically profitable post-emergence control of some annual broad-leaves weeds in sunflower. Original populations SURES-1 and SURES-2 are homozygous for resistance to tribenuron-methyl. F1 generations produced from the crossings are completely resistant to tribenuron-methyl, pointing out to dominant way of inheritance of this trait. Studies on the exact number of genes controlling the resistance are in progress. Tribenuron-methyl resistance was transferred from original populations into a number of female and male inbred lines of cultivated sunflower. These inbred lines could enable creation of a number of hybrids resistant to tribenuron-methyl. Hybrids SUMO-1-PR, SUMO-2- OR and SUMO-3 are resistant to doubled application dose of tribenuron-methyl. Agronomical characteristics of these hybrids are on the level with the leading conventional sunflower hybrids.

  11. Transcriptional Dynamics of LTR Retrotransposons in Early Generation and Ancient Sunflower Hybrids

    Science.gov (United States)

    Ungerer, Mark C.; Kawakami, Takeshi

    2013-01-01

    Hybridization and abiotic stress are natural agents hypothesized to influence activation and proliferation of transposable elements in wild populations. In this report, we examine the effects of these agents on expression dynamics of both quiescent and transcriptionally active sublineages of long terminal repeat (LTR) retrotransposons in wild sunflower species with a notable history of transposable element proliferation. For annual sunflower species Helianthus annuus and H. petiolaris, neither early generation hybridization nor abiotic stress, alone or in combination, induced transcriptional activation of quiescent sublineages of LTR retrotransposons. These treatments also failed to further induce expression of sublineages that are transcriptionally active; instead, expression of active sublineages in F1 and backcross hybrids was nondistinguishable from, or intermediate relative to, parental lines, and abiotic stress generally decreased normalized expression relative to controls. In contrast to findings for early generation hybridization between H. annuus and H. petiolaris, ancient sunflower hybrid species derived from these same two species and which have undergone massive proliferation events of LTR retrotransposons display 2× to 6× higher expression levels of transcriptionally active sublineages relative to parental sunflower species H. annuus and H. petiolaris. Implications and possible explanations for these findings are discussed. PMID:23335122

  12. Resistance of sunflower hybrids to imazamox and tribenuron-methyl

    DEFF Research Database (Denmark)

    Bozic, D; Saric, M; Malidza, G

    2012-01-01

    The response of the imazamox resistant and susceptible sunflower hybrids Rimi and S to imazamox and of tribenuron-methyl resistant and susceptible hybrids Rsu and S to tribenuron-methyl was investigated both in a whole-plant bioassay and in field experiments. Plants were treated post-emergence wi...

  13. Characterization of F1 interspecific hybrids between wild Helianthus annuus L. populations and cultivated sunflower

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    Terzić Sreten

    2006-01-01

    Full Text Available Phenotype, chromosomes pairing and pollen vitality were compared between parental populations and F1 hybrids of interspecific cross between Helianthus annuus L. and cultivated sunflower. The investigation of the simple sequence repeats (SSR polymorphism was also used to test the hybrid nature of F1 populations. The phenotypic traits of F1 hybrid plants were either closer to the wild species or intermediate. Irregular chromosome pairing was found in only 0 to 10% of meiocytes in the meiosis of F1 hybrid plants. Interspecific crosses were confirmed with SSR markers in all hybrid combinations. Alleles that were not present in parental DNA were frequently observed in F1 hybrids. That is additional evidence that those hybrid combinations were not produced by self-fertilization. The results suggest that SSR markers can be efficiently used for the F1 hybrid characterization in crosses between closely related species, in which, the changes of phenotype, meiosis and pollen vitality are not always significant.

  14. Response of sunflower hybrids to management practices under ...

    African Journals Online (AJOL)

    user

    2011-03-21

    Mar 21, 2011 ... It was therefore the objective of this study to evaluate the interactive effects of hybrids, planting geometries and nitrogen rates on the ontogeny growth, fraction of inter- cepted radiation, intercepted PAR, yield components and oil quality of sunflower under irrigated arid environmental conditions. MATERIALS ...

  15. Response of sunflower hybrids to management practices under ...

    African Journals Online (AJOL)

    ... (BZU) Multan, Pakistan, during the spring season of 2009 to study the interactive effect of sunflower (Helianthus annuus L.) hybrids in terms of growth, fraction of intercepted radiation (Fi), intercepted photo-synthetically active radiation (PAR), yield components and oil contents to planting geometries and nitrogen rates.

  16. Drought Stress Responses of Sunflower Germplasm Developed after Wide Hybridization

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    Roumiana Dimova Vassilevska-Ivanova

    2016-10-01

    Full Text Available Response of sunflower germplasms viz. cultivated sunflower H. annuus and two breeding lines H. annuus x T. rotundifolia and H. annuus x V. encelioides developed after wide hybridization were used for identification of drought tolerant sunflower genotypes at the seedling growth stage. Three water stress levels of zero (control, -0.4, and -0.8 MPa were developed using polyethyleneglycol-6000 (PEG-6000. Physiological and biochemical stress determining parameters such as root and shoots length, fresh weight, antioxidant enzyme activities (superoxide dismutase (SOD, catalase (CAT, guaiacol peroxidase (GPO, ascorbate peroxidase (APX and antioxidant metabolite content (total antioxidant capacity, total phenols and total flavonoids content were compared between seedlings of all three genotypes. Results revealed that sunflower genotypes have similar responses at two osmotic potentials for shoot and root length and fresh weight. The data also showed that drought stresss could induce oxidative stress, as indicated by the increase level of ascorbate peroxidase and guaiacol peroxidase at -04 MPa in H. annuus cv 1114. Although the activity of ascorbate peroxidase and guaiacol peroxidase was differentially influenced by drought, the changes of antioxidant enzyme activities such as catalase, superoxide dismutase, guaiacol peroxidase, and ascorbate peroxidase subjected to drought stress follow a similar pattern in both breeding lines, indicating that similar defense systems might be involved in the oxidative stress injury in sunflowers. Increase in content of phenols and flavonoids were detected for all three genotypes under stress, which showed that these were major antioxidant metabolites in scavenging cellular H2O2.

  17. Irrigation method does not affect wild bee pollinators of hybrid sunflower

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    Hillary Sardiñas

    2016-09-01

    Full Text Available Irrigation method has the potential to directly or indirectly influence populations of wild bee crop pollinators nesting and foraging in irrigated crop fields. The majority of wild bee species nest in the ground, and their nests may be susceptible to flooding. In addition, their pollination of crops can be influenced by nectar quality and quantity, which are related to water availability. To determine whether different irrigation methods affect crop pollinators, we compared the number of ground-nesting bees nesting and foraging in drip- and furrow-irrigated hybrid sunflower fields in the Sacramento Valley. We found that irrigation method did not impact wild bee nesting rates or foraging bee abundance or bee species richness. These findings suggest that changing from furrow irrigation to drip irrigation to conserve water likely will not alter hybrid sunflower crop pollination.

  18. New sunflower hybrids tolerant to tribenuron-methyl

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    Cvejić Sandra

    2016-01-01

    Full Text Available The creation of sunflower hybrids tolerant to tribenuron-methyl enabled the use of wider palette of herbicides to control effectively weeds during the growing season. Moreover, thanks to this tolerance, chemical control of broad-leaves weeds in sunflower, especially Cirsium arvense, is more efficient. The Institute of Field and Vegetable Crops offers four new hybrids tolerant to tribenuron-methyl: NS SUMO SUN, NS SUMO STAR, NS SUMO SjAj and NS SUMO SOL, released in 2016. Hybrids belong to early and medium-early maturity groups; have high yield potential and high oil content. They are adapted for cultivation in different environmental conditions. All hybrids are resistant to broomrape (Orobanche cumana Wallr races from A-E and have a high level of tolerance to Phomopsis, white rot (Sclerotinia sclorotiorum, rust (Puccinia helianthi and others. The paper presents the results of seed and oil yield from the official trials of the Department of variety registration within the Ministry of Agriculture and Environmental Protection of the Republic of Serbia.

  19. Borneo: The new NS sunflower confectionary type hybrid

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    Hladni Nada

    2009-01-01

    Full Text Available At the Institute of Field and Vegetable Crops in Novi Sad, beside the basic direction in sunflower breeding, the creation of standard hybrids with high oil content with high seed and oil yield, hybrids are being created for special confectionery purposes directed towards the final kernel products. In this program, apart from breeding in order to improve main seed yield components, special attention is given to the increase of protein content and the quality with the decrease of seed oil content, to the increase of the weight of 1000 seeds and to the decrease of content of the shell. Two-line SC hybrid was created by crossing the cytoplasmatic male sterile line of the mother with a father line with fertility restoration genes. Borneo is a high protein confectionary type hybrid that has been registered in Slovakia (EU in 2009. It contains successfully combined genes responsible for high genetic potential for yield and valuable technical and technological seed traits. The hybrid is adequate for nutrition, dehuling and kernel production. Borneo is a medium early hybrid with the genetic potential for yield of over 4,5t/ha and its seed oil content is under 43%. .

  20. Genome-scale transcriptional analyses of first-generation interspecific sunflower hybrids reveals broad regulatory compatibility.

    Science.gov (United States)

    Rowe, Heather C; Rieseberg, Loren H

    2013-05-23

    Interspecific hybridization creates individuals harboring diverged genomes. The interaction of these genomes can generate successful evolutionary novelty or disadvantageous genomic conflict. Annual sunflowers Helianthus annuus and H. petiolaris have a rich history of hybridization in natural populations. Although first-generation hybrids generally have low fertility, hybrid swarms that include later generation and fully fertile backcross plants have been identified, as well as at least three independently-originated stable hybrid taxa. We examine patterns of transcript accumulation in the earliest stages of hybridization of these species via analyses of transcriptome sequences from laboratory-derived F1 offspring of an inbred H. annuus cultivar and a wild H. petiolaris accession. While nearly 14% of the reference transcriptome showed significant accumulation differences between parental accessions, total F1 transcript levels showed little evidence of dominance, as midparent transcript levels were highly predictive of transcript accumulation in F1 plants. Allelic bias in F1 transcript accumulation was detected in 20% of transcripts containing sufficient polymorphism to distinguish parental alleles; however the magnitude of these biases were generally smaller than differences among parental accessions. While analyses of allelic bias suggest that cis regulatory differences between H. annuus and H. petiolaris are common, their effect on transcript levels may be more subtle than trans-acting regulatory differences. Overall, these analyses found little evidence of regulatory incompatibility or dominance interactions between parental genomes within F1 hybrid individuals, although it is unclear whether this is a legacy or an enabler of introgression between species.

  1. The genomic organization of Ty3/gypsy-like retrotransposons in Helianthus (Asteraceae) homoploid hybrid species.

    Science.gov (United States)

    Staton, S Evan; Ungerer, Mark C; Moore, Richard C

    2009-09-01

    The origin of new diploid, or homoploid, hybrid species is associated with rapid genomic restructuring in the hybrid neospecies. This mode of speciation has been best characterized in wild sunflower species in the genus Helianthus, where three homoploid hybrid species (H. anomalus, H. deserticola, and H. paradoxus) have independently arisen via ancient hybridization events between the same two parental species (H. annuus and H. petiolaris). Most previous work examining genomic restructuring in these sunflower hybrid species has focused on chromosomal rearrangements. However, the origin of all three homoploid hybrid sunflower species also is associated with massive proliferation events of Ty3/gypsy-like retrotransposons in the hybrid species' genomes. We compared the genomic organization of these elements in the parent species and two of the homoploid hybrid species using fluorescence in situ hybridization (FISH). We found a significant expansion of Ty3/gypsy-like retrotransposons confined to the pericentromeric regions of two hybrid sunflower species, H. deserticola and H. paradoxus. In contrast, we detected no significant increase in the frequency or extent of dispersed retrotransposon populations in the hybrid species within the resolution limits of our assay. We discuss the potential role that transposable element proliferation and localization plays in the evolution of homoploid hybrid species.

  2. Genome-scale transcriptional analyses of first-generation interspecific sunflower hybrids reveals broad regulatory compatibility

    OpenAIRE

    Rowe, Heather C.; Rieseberg, Loren H.

    2013-01-01

    Background Interspecific hybridization creates individuals harboring diverged genomes. The interaction of these genomes can generate successful evolutionary novelty or disadvantageous genomic conflict. Annual sunflowers Helianthus annuus and H. petiolaris have a rich history of hybridization in natural populations. Although first-generation hybrids generally have low fertility, hybrid swarms that include later generation and fully fertile backcross plants have been identified, as well as at l...

  3. Genome-scale transcriptional analyses of first-generation interspecific sunflower hybrids reveals broad regulatory compatibility

    Science.gov (United States)

    2013-01-01

    Background Interspecific hybridization creates individuals harboring diverged genomes. The interaction of these genomes can generate successful evolutionary novelty or disadvantageous genomic conflict. Annual sunflowers Helianthus annuus and H. petiolaris have a rich history of hybridization in natural populations. Although first-generation hybrids generally have low fertility, hybrid swarms that include later generation and fully fertile backcross plants have been identified, as well as at least three independently-originated stable hybrid taxa. We examine patterns of transcript accumulation in the earliest stages of hybridization of these species via analyses of transcriptome sequences from laboratory-derived F1 offspring of an inbred H. annuus cultivar and a wild H. petiolaris accession. Results While nearly 14% of the reference transcriptome showed significant accumulation differences between parental accessions, total F1 transcript levels showed little evidence of dominance, as midparent transcript levels were highly predictive of transcript accumulation in F1 plants. Allelic bias in F1 transcript accumulation was detected in 20% of transcripts containing sufficient polymorphism to distinguish parental alleles; however the magnitude of these biases were generally smaller than differences among parental accessions. Conclusions While analyses of allelic bias suggest that cis regulatory differences between H. annuus and H. petiolaris are common, their effect on transcript levels may be more subtle than trans-acting regulatory differences. Overall, these analyses found little evidence of regulatory incompatibility or dominance interactions between parental genomes within F1 hybrid individuals, although it is unclear whether this is a legacy or an enabler of introgression between species. PMID:23701699

  4. Analysis the parameters of seed quality in ns sunflower hybrid after processing in gravity separator

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    Jokić Goran

    2016-01-01

    Full Text Available This paper analyzed the processed seed of five sunflower hybrid seed developed at the Institute of Field and Vegetable Crops in Novi Sad before and after processing in gravity separator. The cultivars were Pegaz, Duško, NS Fantazija, Sumo 1 PR and NS Oskar. The analysis was conducted on seed lots processed in 2015 and involved the following parameters: seed purity percentage, 1.000-seed weight, germination energy, germination, seed moisture, number of sclerotinia per 1.000. The results showed that all the parameters of seed quality of sunflower hybrids were better after processing seeds in the gravity separator.

  5. Genetic analysis of agro-morphological traits in promising hybrids of sunflower (Helianthus annuus L.

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    Maryam GOLABADI

    2015-11-01

    Full Text Available The main objective underlying sunflower breeding programs is to develop high-yielding productive F1 hybrid cultivars. This study was conducted to investigate the genetic control of some agro-morphological traits of new sunflower F1 hybrids. For this purpose, fourteen inbred lines of sunflower were crossed with three male sterile inbred lines. Their hybrids (14 hybrids were then evaluated against three control cultivars. The data thus obtained were analyzed using the nested model (North Carolina Design І as a completely randomized block design (CRBD with four replications. Analysis of variance showed that the hybrids were significantly different in all the traits studied, except for head and stem diameters. From among the hybrids evaluated, Cms19 × Rn1-81 was found to have the highest seed yield and oil content. Cluster analysis classified the hybrids into four different groups. Genetic analysis showed that days to maturity, seed weight, and oil content (% were under the additive gene action. Breeding strategies based on selection could be suggested for the improvement of these traits. Head angle, head diameter, seed yield, and oil yield were under the dominance gene action; breeding based on hybridization methods is, therefore, proposed for these traits. Finally, both additive and dominance gene actions were observed to play important roles in the genetic control of plant height and stem diameter.

  6. Sorting through the chaff, nDNA gene trees for phylogenetic inference and hybrid identification of annual sunflowers (Helianthus sect. Helianthus).

    Science.gov (United States)

    Moody, Michael L; Rieseberg, Loren H

    2012-07-01

    The annual sunflowers (Helianthus sect. Helianthus) present a formidable challenge for phylogenetic inference because of ancient hybrid speciation, recent introgression, and suspected issues with deep coalescence. Here we analyze sequence data from 11 nuclear DNA (nDNA) genes for multiple genotypes of species within the section to (1) reconstruct the phylogeny of this group, (2) explore the utility of nDNA gene trees for detecting hybrid speciation and introgression; and (3) test an empirical method of hybrid identification based on the phylogenetic congruence of nDNA gene trees from tightly linked genes. We uncovered considerable topological heterogeneity among gene trees with or without three previously identified hybrid species included in the analyses, as well as a general lack of reciprocal monophyly of species. Nonetheless, partitioned Bayesian analyses provided strong support for the reciprocal monophyly of all species except H. annuus (0.89 PP), the most widespread and abundant annual sunflower. Previous hypotheses of relationships among taxa were generally strongly supported (1.0 PP), except among taxa typically associated with H. annuus, apparently due to the paraphyly of the latter in all gene trees. While the individual nDNA gene trees provided a useful means for detecting recent hybridization, identification of ancient hybridization was problematic for all ancient hybrid species, even when linkage was considered. We discuss biological factors that affect the efficacy of phylogenetic methods for hybrid identification.

  7. Patterns of genetic diversity and candidate genes for ecological divergence in a homoploid hybrid sunflower, Helianthus anomalus

    Science.gov (United States)

    SAPIR, YUVAL; MOODY, MICHAEL L.; BROUILLETTE, LARRY C.; DONOVAN, LISA A.; RIESEBERG, LOREN H.

    2008-01-01

    Natural hybridization accompanied by a shift in niche preference by hybrid genotypes can lead to hybrid speciation. Natural selection may cause the fixation of advantageous alleles in the ecologically diverged hybrids, and the loci experiencing selection should exhibit a reduction in allelic diversity relative to neutral loci. Here, we analyzed patterns of genetic diversity at 59 microsatellite loci associated with expressed sequence tags (ESTs) in a homoploid hybrid sunflower species, Helianthus anomalus. We used two indices, ln RV and ln RH, to compare variation and heterozygosity (respectively) at each locus between the hybrid species and its two parental species, H. annuus and H. petiolaris. Mean values of ln RV and ln RH were significantly lower than zero, which implies that H. anomalus experienced a population bottleneck during its recent evolutionary history. After correcting for the apparent bottleneck, we found six loci with a significant reduction in variation or with heterozygosity in the hybrid species, compared to one or both of the parental species. These loci should be viewed as a ranked list of candidate loci, pending further sequencing and functional analyses. Sequence data were generated for two of the candidate loci, but population genetics tests failed to detect deviations from neutral evolution at either locus. Nonetheless, a greater than eight-fold excess of nonsynonymous substitutions was found near a putative N-myristoylation motif at the second locus (HT998), and likelihood-based models indicated that the protein has been under selection in H. anomalus in the past and, perhaps, in one or both parental species. Finally, our data suggest that selective sweeps may have united populations of H. anomalus isolated by a mountain range, indicating that even low gene-flow species may be held together by the spread of advantageous alleles. PMID:17944850

  8. Evaluation of NS sunflower hybrids in small-plot trials via hybrid × location interaction

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    Balalić Igor

    2012-01-01

    Full Text Available The aim of this study was to evaluate NS sunflower hybrids on the basis of the results of seed yield, seed oil content and oil yield obtained in a network of small-plot trials in Serbia in 2011. The trial included 9 hybrids and 14 locations. Seed yield, seed oil content and oil yield were significantly different in small-plot trials in the investigated regions of Serbia. The highest average seed yield was produced by Sremac (3.67 t ha-1, Velja (3.62 t ha-1, Duško (3.56 t ha-1 and Novosađanin (3.55 t ha-1. On the location Rimski šančevi the seed yield (4.48 t ha-1 was significantly highest. Average oil content for hybrids grown in 14 locations was 47.25%. Hybrids Baća (50.26%, NS-H-111 (48.91%, Bačvanin (48.70% and Novosađanin (47.83% showed the highest average seed oil content. The highest average oil yield was produced by Baća (1.71 t ha-1, Novosađanin (1.70, Velja (1.67 t ha-1, Sremac (1.63 t ha-1 and NS-H-111 (1.63 t ha-1. Locations with the highest oil yield were Rimski šančevi (2.03 t ha-1 and Sombor (1.96 t ha-1. In the four-year trials in Vojvodina, the average seed yield of 9 hybrids was 3.35 t ha-1. Seed yield over general mean was reached by three hybrids (Duško, Sremac and Velja. The highest seed yield was reached by hybrid Duško (3.56 t ha-1. AMMI1 biplot showed that most stable and with high seed and oil yield were the hybrids Duško, Sremac and Baća, and for oil content Baća, Bačvanin and NS-H-111.

  9. Minireview: importance of herbicide-tolerant sunflower hybrids in suppressing common ragweed (Ambrosia artemisiifolia pollen production

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    Peter Reisinger

    2014-01-01

    Full Text Available Common ragweed (Ambrosia artemisiifolia is the number one weed in Hungary: it covers ca. 5% of the arable land, causing huge losses in row crops, especially in sunflowers. In addition, because of the high allergenicity of its pollen, common ragweed is a heavy burden on the health care system. This minireview discusses the importance of use of herbicide-tolerant sunflower hybrids in eliminating common ragweed from sunflower fields, with special emphasis on the efficacy of common ragweed control of two acetolactate-synthase inhibitor postemergence herbicides (imazamox and tribenuron methyl in several sunflower hybrids that carry the resistance gene against such herbicides. Common ragweed control by these herbicides was excellent: they suppressed the growth of the weed plant until the canopy closure of the crop (8-leaf stage. Common ragweed plants germinating after this date were unable to compete with the crop: although they survived, they remained small (ca. 70% reduction in height, produced ca. 90% less male inflorescences (source of the allergenic pollen, and caused no significant reduction in the crop yield. In order to stop the seed production by the few late-germinating weed plants we recommend a mechanical common measure (row-cultivator in late August.

  10. IMPORTANCE OF STORAGE CONDITIONS AND SEED TREATMENT FOR SUNFLOWER HYBRIDS SEEDS GERMINATION

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    Goran Krizmanić

    2014-12-01

    Full Text Available In this research we have determined germination energy and germination of seeds of sunflower hybrids ‘Luka’ and ‘Apolon’, at the beginning of storage and 6, 12 and 18 months after of storage period (2011-2012 in the floor concrete storage at two different air temperatures and humidity (S-1: air temperature 15-18°C and relative air humidity 65-70% as well as in climate chamber (S-2: air temperature 10-12°C and relative air humidity 60-65%, stored in four treatments (Control: processed-untreated seed; T-1: treated with A.I. metalaxyl-M; T-2: treated with A.I. metalaxyl-M + A.I. imidacloprid and T-3: treated with A.I. metalaxyl-M + A.I. clothianidin. Based on the obtained results we have determined that sunflower hybrid ‘Luka’, compared to hybrid ‘Apolon’, in the given storage conditions and with the same seed treatment has 5-8% higher germination energy and seed germination and that in climate chamber both hybrids have 5-7% higher germination energy. Seed treatment of both sunflower hybrids with A.I. imidacloprid maximally reduced initial germination energy and seed germination in all tested periods and conditions of storage. On the average, natural seed, after 18 months of storage did not have better seed quality compared to seed treated with A.I. metalaxyl-M while other treatments had more significant influence on reduction of germination energy and seed germination, 6-15%. On the average, compared to other variants, seeds treated with A.I. metalaxyl-M after 18 months of storage in both storage conditions had higher germination energy by 4-15%, and seed germination by 2-12%.

  11. Agronomic and production characteristics of sunflower hybrids: NS Oskar and NS Fantazija

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    Cvejić Sandra

    2014-01-01

    Full Text Available The results of seed and oil yield obtained from the trials and production plots, single out sunflower hybrids NS Oskar and NS Fantazija as very promising and potentially leading in Serbia. They were created by breeding process at the Institute of Field and Vegetable Crops, Novi Sad. Hybrids are medium early ie. late maturity sunflower hybrids, have high yielding potential and high oil content. They are adjusted to different agro ecological conditions because they have wide adaptability to the different conditions of production. They also possess a high degree of tolerance and resistance to major parasites in the region, such as downy mildew, Phomopsis, white rot, broomrape etc. Hybrid seed is of excellent quality and germination. This paper presents the results of seed yield in trials from Department for variety testing of Ministry of Agriculture and environmental protection of the Republic of Serbia, as well as the results achieved in small-plot trials of the Institute of Field and Vegetable Crops and results from farm producers.

  12. Soluble fractions and kinetics parameters of nitrate and ammonium uptake in sunflower (“Neon” Hybrid

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    Luiziene Soares Alves

    Full Text Available ABSTRACT Sunflower plants are source of oilseeds with great importance for agroenergy. Nitrogen deficiency is considered one of the factors limiting growth and yield. The objective of this study was to assess the nitrogen uptake (high and low supply of nitrate and ammonium and to determine the uptake kinetics parameters (Km and Vmax of these ions in sunflower plants (Neon hybrid. The experiment was carried out in a growth chamber using a hydroponic system. The following treatments were applied: 0.2 and 2.0 mmol L-1 of N-NO3- and N-NH4+. The two kinetics parameters (Km and Vmax involved in the uptake of nitrate and ammonium were determined, as well as the soluble fractions (N-NO3-, N-NH4+, amino-N and sugars and total N, in different plant tissues. The plants grown with ammonium showed higher Vmax than those cultivated with nitrate. High ammonium rates caused reduction of root volume and the plants supplied with 2.0 mmol L-1 of N-NO3- produced more biomass from the roots and aerial part. The highest concentrations of NNO3- were found in the petioles. Analyzed together, the data suggest a greater potential for use of nitric-N as a nitrogen source for fertilization in the cultivation of sunflower.

  13. Effects of High Temperature and Water Stress on Seed Germination of the Invasive Species Mexican Sunflower.

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    Wen, Bin

    2015-01-01

    Mexican sunflower is native to Mexico and Central America and was introduced into China early last century. Now it has widely naturalized and is exhibiting increasing invasiveness in South China. As this species often dominates bare ground, a habitat characterized by extreme fluctuation in temperature and water, it is reasonable to hypothesize that it has special adaptations to high temperature and water stress. Using laboratory experiments to simulate these stresses, this study investigated the response of Mexican sunflower seed germination to temperature and water stress, and compared these responses with those previously reported for another invasive, bamboo piper, which is confined to relatively cool and moist habitats in Xishuangbanna. As expected, Mexican sunflower seeds exhibited higher tolerance to these stresses than bamboo piper. Germination of Mexican sunflower seeds was highest at 15-30°C, but significant numbers of seeds germinated and formed seedlings at 10°C and 35°C, at which no bamboo piper seeds formed seedlings, indicating a wider temperature range for germination than the latter. Roughly half the seeds survived 240 h continuous heat treatment and up to 15 h daily periodical heat treatment at 40°C, while bamboo piper seeds were mostly killed by these treatments. About 20% of Mexican sunflower but no bamboo piper seeds germinated after heat treatment for 30 min at 80°C. Germination was completely inhibited in bamboo piper seeds at -0.6 mPa, while 20-60% of Mexican sunflower seeds germinated depending on PEG or NaCl as osmoticum. This higher tolerance in Mexican sunflower seeds accords with its stronger invasiveness in this area. This comparison between two plant invaders demonstrates that invasiveness is not an all-or-nothing situation, and that adaptation to local habitats is a critical determinant of successful invasiveness for an alien plant.

  14. Comparative Research of Qualitative Characteristics in Nowadays Varieties and Hybrids of Sunflower (Helianthus annuus L. by Plant Varieties Examination

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    О. О. Шовгун

    2009-12-01

    Full Text Available A comparative research of qualitative characteristics has been performed on qualitative characteristics of modern varieties and hybrids of Sunflower for the five years of research and technical examination in various soil and climate conditions: Steppe, Forest-Steppe. Regularities have been established of the oil fatty-acid composition variability during examination and varieties and hybrids of improved fatty-acid composition have been detected. High-protein and large-fruit sunflower varieties for confectionary use have  been detected.

  15. Stem cankers on sunflower (Helianthus annuus) in Australia reveal a complex of pathogenic Diaporthe (Phomopsis) species

    NARCIS (Netherlands)

    Thompson, S.M.; Tan, Y.P.; Young, A.J.; Neate, S.M.; Aitken, E.A.B.; Shivas, R.G.

    2012-01-01

    The identification of Diaporthe (anamorph Phomopsis) species associated with stem canker of sunflower (Helianthus annuus) in Australia was studied using morphology, DNA sequence analysis and pathology. Phylogenetic analysis revealed three clades that did not correspond with known taxa, and these are

  16. Somatic embryogenesis from corolla tubes of interspecific amphiploids between cultivated sunflower (Helianthus annuus L.) and its wild species

    Science.gov (United States)

    Somatic embryogenesis in vitro provides an efficient means of plant multiplication, facilitating sunflower improvement and germplasm innovation. In the present study, using interspecific amphiploids (2n=4x=68) between cultivated sunflower and wild perennial Helianthus species as explant donors, soma...

  17. Effect of hybrid, storage conditions and seed protection on sunflower field emergence

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    Mrđa Jelena

    2010-01-01

    Full Text Available Seed emergence under field conditions decisively and directly determines the number of plants per hectare, which is one of three basic components of yield in the plant world. Influence of chemical treatment on field emergence of three commercial sunflower hybrids stored in different conditions was tested in 2007 and 2008 on experimental field of Institute of Field and Vegetable Crops in Novi Sad. On average, hybrid H1 had the highest value of field emergence (88.79% and for chemical treatment fl udioxonil + metalaxyl + imidacloprid (87.71%. Seed kept in common storage had the highest emergence value in fi eld (87.92%. Seed treated with fl udioxonil + metalaxyl + imidacloprid and stored for one year in common storage had the highest field emergence (90.18%. Considering interaction between storage conditions and genotype, hybrid H1 seed sown after chemical treatment had the highest field emergence (91.82% and seed kept in common storage (90.48%. Hybrid H1 seed compared with other two had the highest field emergence treated with fludioxonil + metalaxyl + imidacloprid (91.84%.

  18. Productivity of NS sunflower hybrids in small-plot trials in Serbia in 2010

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    Miklič Vladimir

    2011-01-01

    Full Text Available The objective of this study was the evaluation of NS sunflower hybrids on the basis of the results of seed yield, seed oil content and oil yield obtained in a network of small-plot trials in Vojvodina and central Serbia in 2010, as well as recommendations for the sowing season 2011. Seed yield, seed oil content and oil yield were significantly different in small-plot trials in the investigated regions. In Vojvodina, the highest average seed yield was produced by Duško (3.08 t ha-1, Sremac (2.98 t ha-1, Orfej (2.97 t ha-1 Velja (2.93 t ha-1 and NS-H-111 (2.92 t ha-1. In the region of central Serbia, the highest seed yield was achieved by the hybrids NS-H-111 (2.97 t ha-1 and Duško (2.87 t ha-1. Hybrid Baća showed the highest average seed oil content both in the region of Vojvodina (48.54% and central Serbia (48.80%. The highest average oil yield (over 1.30 t ha-1 was produced by Duško, Bačvanin and NS-H-111 in the Vojvodina region, and in central Serbia oil yield (over 1.30 t ha-1 by NS-H-111, Oskar and Novosađanin. In the three-year trials in Vojvodina four hybrids (Duško, Sremac, Velja and NS-H-111 showed seed yield over general mean. The highest seed yield was reached by hybrid Duško (3.54 t ha-1.

  19. The chemical control of Sorghum halepense species in sunflower culture, in the Danube meadow.

    Science.gov (United States)

    Poienaru, S; Sarpe, N; Sarpe, I

    2005-01-01

    In the latest years, sunflower was cultivated in Romania on an area of 800-900 thousand hectares. On 100 or 150 thousand hectares we find it cultivated also in agricultural farms in the Danube Meadow, because sunflower has favorable conditions on these soils, productions exceeding sometimes over 4000 kg/ha, of course, in irrigation conditions. In the Danube Meadow, the first experiments on Sorghum halepense (Johnson grass) species were performed by Fane Popa and colleagues (1986), at the agricultural station of Braila, using the herbicide Fusilade. In our experiments, the herbicide fusillade was compared with different more recently synthesized herbicides: Super, Pantera, Agil, Select, with the specific purpose of identifying the most favorable dose.

  20. INFLUENCE OF WEATHER CONDITIONS ON GRAIN YIELD, OIL CONTENT AND OIL YIELD OF NEW OS SUNFLOWER HYBRIDS

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    Anto Mijić

    2017-01-01

    Full Text Available With the purpose of determining the influence of weather conditions on the yield components of sunflower, the results of three-year field trials are analysed in the paper. In the trials sown in Osijek in 2013, 2014 and 2015, there were 15 sunflower hybrids: two foreign hybrids and 13 hybrid combinations of the Agricultural Institute Osijek. In the period before sowing (January – March, the highest amount of precipitation was in 2013 (213.1 mm, then in 2015 (167.9 mm, and the lowest in 2014 (109.5 mm. In the growing period (April – September, the highest amount of precipitation (487.3 mm was in 2014, 475.7 mm in 2013, and in 2015 it was the lowest (251.6 mm. In 2013, during the growing period, the mean monthly air temperature was 19.1°C, in 2015 19.9°C, and in 2014 18.6°C. Of these years, statistically significant at the P=0.05, the highest value of the analysed traits was recorded in 2013: grain yield of 6.47 t ha-1, oil content 51.69% and oil yield 3.05 t ha-1. Grain yield, oil content and oil yield were lower in 2015, and the lowest in 2014. Matej, a newly recognized sunflower hybrid of the Agricultural Institute Osijek had the highest values of grain and oil yield (6.95 and 3.39 t ha-1, and by its oil content of 53.44%, it was in the third place. For high grain and oil yields of sunflower, in addition to the optimal air temperature, the amount and distribution of precipitation before and also during the growing season are very important.

  1. Analysis of relations between crop temperature indices and yield of different sunflower hybrids foliar treated by biopreparations

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    Kovár Marek

    2016-04-01

    Full Text Available The application of biological active preparations (BAPs and remote-sensing control in the management of agronomic intervention are an important part of successful crop cultivation. The effects of foliar application of two BAPs (containing amino acids or Abiestins® on yield and yield-forming, as well eco-physiological traits calculated from infrared thermographs data (crop water stress index, CWSI and index of stomatal conductance, Ig of three hybrids of sunflower were studied in field poly-factorial experiments, realised during two years (2012 and 2013. The results showed that the application of selected BAPs has contributed to an increase of the sunflower yield, in particular through an increase in the weight of thousand seeds (rp = 0.761, P < 0.001. Similarly, oil content in achenes was significantly higher in treatments with BAPs, mainly with preparation containing free amino acids. The study describes the quantitative relationship between yield and quality of sunflower production (rp = −0.41, P < 0.01. Selected hybrids of sunflower in two growth stages showed the significant differences in CWSI and Ig (both at P < 0.01, respectively. An analysis of negative linear relation between the yield of achenes and CWSI (rp = −0.654, P < 0.001 confirmed that higher value of plant stress resulted in a smaller yield and vice-versa. The opposite trend was observed between yield and Ig index (rp = 0.576, P < 0.001. The data obtained from IR thermography can be used for monitoring the physiological health of sunflower plants, as well in potential prediction and control of yield.

  2. Nitrogen and phosphorus management strategy for better growth and yield of sunflower (Helianthus annuus L. hybrid

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    Amjed Ali and Ijaz Rasool Noorka

    2013-05-01

    Full Text Available This study conducted during autumn season, 2010 investigated the effect of nitrogen and phosphorus on sunflower hybrid Hysun-33. The experiment was planned in randomized complete block design (factorial arrangement, with three replication, having net plot size of 3 x 7 m. The experiment comprised of 9 treatments, three levels of nitrogen and phosphorus, viz., 85, 135, 185 kg N ha-1, and 50, 75, 85 kg P ha-1. Nitrogen affected all estimated characters significantly, except plant population, while, phosphorus did not show significant effect on plant population and plant height. All other parameters, as leaf area plant-1, head diameter, 1000- achene weight and achene yield were affected significantly by different nitrogen and phosphorus levels. Interactive effects of nitrogen and phosphorus were significant in all these cases. The highest achene’s yield (2584 kg ha-1 was obtained with the application of 135-75 kg NP ha-1as against the lowest (1491kg ha-1 at 85-50 kg NP ha-1.

  3. Selection on leaf ecophysiological traits in a desert hybrid Helianthus species and early-generation hybrids.

    Science.gov (United States)

    Ludwig, Fulco; Rosenthal, David M; Johnston, Jill A; Kane, Nolan; Gross, Briana L; Lexer, Christian; Dudley, Susan A; Rieseberg, Loren H; Donovan, Lisa A

    2004-12-01

    Leaf ecophysiological traits related to carbon gain and resource use are expected to be under strong selection in desert annuals. We used comparative and phenotypic selection approaches to investigate the importance of leaf ecophysiological traits for Helianthus anomalus, a diploid annual sunflower species of hybrid origin that is endemic to active desert dunes. Comparisons were made within and among five genotypic classes: H. anomalus, its ancestral parent species (H. annuus and H. petiolaris), and two backcrossed populations of the parental species (designated BC2ann and BC2pet) representing putative ancestors of H. anomalus. Seedlings were transplanted into H. anomalus habitat at Little Sahara Dunes, Utah, and followed through a summer growing season for leaf ecophysiological traits, phenology, and fitness estimated as vegetative biomass. Helianthus anomalus had a unique combination of traits when compared to its ancestral parent species, suggesting that lower leaf nitrogen and greater leaf succulence might be adaptive. However, selection on leaf traits in H. anomalus favored larger leaf area and greater nitrogen, which was not consistent with the extreme traits of H. anomalus relative to its ancestral parents. Also contrary to expectation, current selection on the leaf traits in the backcross populations was not consistently similar to, or resulting in evolution toward, the current H. anomalus phenotype. Only the selection for greater leaf succulence in BC2ann and greater water-use efficiency in BC2pet would result in evolution toward the current H. anomalus phenotype. It was surprising that the action of phenotypic selection depended greatly on the genotypic class for these closely related sunflower hybrids grown in a common environment. We speculate that this may be due to either phenotypic correlations between measured and unmeasured but functionally related traits or due to the three genotypic classes experiencing the environment differently as a result of

  4. Sunflower propagation.

    Science.gov (United States)

    Mayor, M L; Nestares, G; Vega, T; Zorzoli, R; Picardi, L A

    2010-01-01

    Sunflower (Helianthus annuus L.) has been cultivated both as an oilseed and as an ornamental plant. Several protocols have been described for the micropropagation, direct plant regeneration by organogenesis being acceptable for this plant species. Besides a strong genotype dependency, the type and ontogenic stage of explants, environmental conditions of the culture, and media composition affect sunflower organogenesis. Several problems have hindered the ability to regenerate normal shoots; the most common being hyperhydricity and precocious flowering. This chapter describes a protocol for direct shoot regeneration from cotyledons developed and established in our laboratory, as well as the improvement regenerated shoot quality.

  5. AMMI model in the evaluation of hybrid × sowing date interaction for seed yield and oil content in sunflower

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    Balalić Igor

    2010-01-01

    Full Text Available In the three year experiment (2005, 2006, 2007 the effects of hybrid, sowing date and their interaction for seed yield and oil content in sunflower were investigated. Three hybrids (Miro, Rimi, Pobednik and eight sowing dates were included in the experiment. AMMI (Additive Main effects and Multiple Interaction model was applied (Gauch & Zobel, 1996. AMMI1 biplot, using excel (macro was done according to Lipkovich & Smith (2002. In the three years average, hybrids did not show significant differences in the mean values for seed yield. Sowing dates had significant portion in the yield formation. The highest seed yield was achieved in the earlier sowing dates. From R3 to R6 the seed yield stagnated, and in R7 and R8 the mean values were significantly lowest. Hybrid Pobednik showed significantly highest oil content. Oil content (three years average was highest in R2, R4 and R5, after that mean values decreased and they were lowest in R7 and R8. AMMI ANOVA for seed yield and oil content showed highly significant values for IPC1 (73,8 % of variation for seed yield and 69,4 % for oil content. On the basis of the stability evaluation for seed yield and oil content on AMMI1 biplot can be seen that hybrid Miro was most stable, and hybrids Pobednik and Rimi were less stable. Highly significant positive correlation with IPC1 for seed yield had pa_cv and rv_cv (precipitation and relative air humidity in the flowering stage and significant correlation rv_fz (relative air humidity in the physiological maturity. Highly significant or significant correlation with first bilinear component for oil content showed tmx_cv, tsd_cv and os_cv (maximum decade temperature, mean decade temperature and insolation in the flowering stage. AMMI1 biplot can help in the recommendation of high yielding, stable sunflower hybrids and most convenient sowing dates. .

  6. Influence of growth regulator on plant growth, development and yield formation of sunflower hybrids (F1 under the conditions of Southern Steppe zone of Ukraine

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    О. А. Єременко

    2017-06-01

    Full Text Available Purpose. To study the effect of AKM plant growth regulator on growth, development and yield formation of sunflower (Helianthus annuus L. hybrids in hybridization plots under the conditions of the Southern Steppe zone of Ukraine. Methods. Laboratory tests, field study, statistical evaluation. Results. The results of studies devoted to determining the optimal AKM concentration for the treatment of seeds of the maternal and paternal lines, the effect of AKM on field germination, biometric parameters of sunflower plants, seed quality (F1 and yield are presented. Three hybrids of the Ukrainian selection, such as ‘Alpha’, ‘Logos’ and ‘Persei’ were studied during 2014–2016. Optimal concentration of AKM (0.0015 g/l was defined. The vigor of seeds processed by AKM was higher than in check variety by 0.8–12.8 р.р. (♂; 0.4–10.7 p.p. (♀, laboratory germination – by 2.3–6.1 p.p. (♂; 3.5–6.2 p.p. (♀. In 2016, the sunflower plant height for all variants exceeded this parameter to be obtained for other years of the study. This could be explained by the fact that HTC in 2016 for the BBCH 00–39 period was 1.4 times higher than in 2015. In general, hybrids as the studied factor considerably influenced sunflower yield, and the share of the hybrid (factor A influence is 33%. This should be considered when selecting hybrids for sunflower cultivation technologies in the Steppe zone of Ukraine. Conclusions. Hydrothermal conditions of the year had the maximum impact on the formation of seed quality and yield of sunflower plants of the hybrids under study, but when using AKM growth regulator for presowing seed treatment, this negative impact was reduced by an average of 23%.

  7. GROWTH PERFORMANCE AND FEED CONVERSION RATIO (FCR OF HYBRID FINGERLINGS (CATLA CATLA X LABEO ROHITA FED ON COTTONSEED MEAL, SUNFLOWER MEAL AND BONE MEAL

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    T. SAHZADI, M. SALIM, UM-E-KALSOOM AND K. SHAHZAD

    2006-10-01

    Full Text Available An experiment was conducted in six glass aquaria to study the growth performance and feed conversion ratio (FCR of hybrid fingerlings (Catla catla x Labeo rohita fed on sunflower meal, cottonseed meal and bone meal. Two replicates for each ingredient were followed. The feed was supplied at the rate of 4% of wet body weight of fingerlings twice a day. The hybrid (Catla catla x Labeo rohita fingerlings gained highest body weight (1.62 ± 0.0 g on sunflower meal, followed by cottonseed meal (1.61 ± 0.01 g and bone meal (1.52 ± 0.0 g. The total length obtained by hybrid fish was 6.35 ± 0.05 cm on sunflower meal, 6.12 ± 0.05 cm on cottonseed meal and 5.85 ± 0.05 cm on bone meal. The overall mean values of FCR were lower (better on sunflower meal (1.78 ± 0.05, followed by cottonseed meal (2.17 ± 0.01 and bone meal (2.46 ± 0.01. Thus, The sunflower meal and cottonseed meal, on the basis of growth performance and better FCR, can be included in the feed formulation for hybrid fingerlings.

  8. Local adaptation within a hybrid species.

    Science.gov (United States)

    Eroukhmanoff, F; Hermansen, J S; Bailey, R I; Sæther, S A; Sætre, G-P

    2013-10-01

    Ecological divergence among populations may be strongly influenced by their genetic background. For instance, genetic admixture through introgressive hybridization or hybrid speciation is likely to affect the genetic variation and evolvability of phenotypic traits. We studied geographic variation in two beak dimensions and three other phenotypic traits of the Italian sparrow (Passer italiae), a young hybrid species formed through interbreeding between house sparrows (P. domesticus) and Spanish sparrows (P. hispaniolensis). We found that beak morphology was strongly influenced by precipitation regimes and that it appeared to be the target of divergent selection within Italian sparrows. Interestingly, however, the degree of parental genetic contribution in the hybrid species had no effect on phenotypic beak variation. Moreover, beak height divergence may mediate genetic differentiation between populations, consistent with isolation-by-adaptation within this hybrid species. The study illustrates how hybrid species may be relatively unconstrained by their admixed genetic background, allowing them to adapt rapidly to environmental variation.

  9. Different histories of two highly variable LTR retrotransposons in sunflower species.

    Science.gov (United States)

    Mascagni, Flavia; Cavallini, Andrea; Giordani, Tommaso; Natali, Lucia

    2017-11-15

    In the Helianthus genus, very large intra- and interspecific variability related to two specific retrotransposons of Helianthus annuus (Helicopia and SURE) exists. When comparing these two sequences to sunflower sequence databases recently produced by our lab, the Helicopia family was shown to belong to the Maximus/SIRE lineage of the Sirevirus genus of the Copia superfamily, whereas the SURE element (whose superfamily was not even previously identified) was classified as a Gypsy element of the Ogre/Tat lineage of the Metavirus genus. Bioinformatic analysis of the two retrotransposon families revealed their genomic abundance and relative proliferation timing. The genomic abundance of these families differed significantly among 12 Helianthus species. The ratio between the abundance of long terminal repeats and their reverse transcriptases suggested that the SURE family has relatively more solo long terminal repeats than does Helicopia. Pairwise comparisons of Illumina reads encoding the reverse transcriptase domain indicated that SURE amplification may have occurred more recently than that of Helicopia. Finally, the analysis of population structure based on the SURE and Helicopia polymorphisms of 32 Helianthus species evidenced two subpopulations, which roughly corresponded to species of the Helianthus and Divaricati/Ciliares sections. However, a number of species showed an admixed structure, confirming the importance of interspecific hybridisation in the evolution of this genus. In general, these two retrotransposon families differentially contributed to interspecific variability, emphasising the need to refer to specific families when studying genome evolution. Copyright © 2017 Elsevier B.V. All rights reserved.

  10. Effects of different mycorrhiza species on grain yield, nutrient uptake and oil content of sunflower under water stress

    OpenAIRE

    Mostafa Heidari; Vahid Karami

    2014-01-01

    The role of arbuscular mycorrhizal fungi in alleviating water stress is well documented. In order to study the effects of water stress and two different mycorrhiza species on grain yield, nutrient uptake and oil content of sunflower, a field experiment as split plot design with three replications was conducted in the Research Field Station, Zabol University, Zabol, Iran in 2011. Water stress treatments included control as 90% of field capacity (W1), 70% field capacity (W2) and 50% field capac...

  11. Involvement of reactive nitrogen and oxygen species (RNS and ROS) in sunflower-mildew interaction.

    Science.gov (United States)

    Chaki, Mounira; Fernández-Ocaña, Ana M; Valderrama, Raquel; Carreras, Alfonso; Esteban, Francisco J; Luque, Francisco; Gómez-Rodríguez, María V; Begara-Morales, Juan C; Corpas, Francisco J; Barroso, Juan B

    2009-02-01

    Nitric oxide (.NO) has been shown to participate in plant response against pathogen infection; however, less is known of the participation of other NO-derived molecules designated as reactive nitrogen species (RNS). Using two sunflower (Helianthus annuus L.) cultivars with different sensitivity to infection by the pathogen Plasmopara halstedii, we studied key components involved in RNS and ROS metabolism. We analyzed the superoxide radical production, hydrogen peroxide content, l-arginine-dependent nitric oxide synthase (NOS) and S-nitrosoglutathione reductase (GSNOR) activities. Furthermore, we examined the location and contents of .NO, S-nitrosothiols (RSNOs), S-nitrosoglutathione (GSNO) and protein 3-nitrotyrosine (NO(2)-Tyr) by confocal laser scanning microscopy (CLSM) and biochemical analyses. In the susceptible cultivar, the pathogen induces an increase in proteins that undergo tyrosine nitration accompanied by an augmentation in RSNOs. This rise of RSNOs seems to be independent of the enzymatic generation of .NO because the l-arginine-dependent NOS activity is reduced after infection. These results suggest that pathogens induce nitrosative stress in susceptible cultivars. In contrast, in the resistant cultivar, no increase of RSNOs or tyrosine nitration of proteins was observed, implying an absence of nitrosative stress. Therefore, it is proposed that the increase of tyrosine nitration of proteins can be considered a general biological marker of nitrosative stress in plants under biotic conditions.

  12. Natural selection drives clinal life history patterns in the perennial sunflower species, Helianthus maximiliani.

    Science.gov (United States)

    Kawakami, Takeshi; Morgan, Theodore J; Nippert, Jesse B; Ocheltree, Troy W; Keith, Rose; Dhakal, Preeti; Ungerer, Mark C

    2011-06-01

    In plants, ecologically important life history traits often display clinal patterns of population divergence. Such patterns can provide strong evidence for spatially varying selection across environmental gradients but also may result from nonselective processes, such as genetic drift, population bottlenecks and spatially restricted gene flow. Comparison of population differentiation in quantitative traits (measured as Q(ST) ) with neutral molecular markers (measured as F(ST) ) provides a useful tool for understanding the relative importance of adaptive and nonadaptive processes in the formation and maintenance of clinal variation. Here, we demonstrate the existence of geographic variation in key life history traits in the diploid perennial sunflower species Helianthus maximiliani across a broad latitudinal transect in North America. Strong population differentiation was found for days to flowering, growth rate and multiple size-related traits. Differentiation in these traits greatly exceeds neutral predictions, as determined both by partial Mantel tests and by comparisons of global Q(ST) values with theoretical F(ST) distributions. These findings indicate that clinal variation in these life history traits likely results from local adaptation driven by spatially heterogeneous environments. © 2011 Blackwell Publishing Ltd.

  13. Selection on crop-derived traits and QTL in sunflower (Helianthus annuus) crop-wild hybrids under water stress.

    Science.gov (United States)

    Owart, Birkin R; Corbi, Jonathan; Burke, John M; Dechaine, Jennifer M

    2014-01-01

    Locally relevant conditions, such as water stress in irrigated agricultural regions, should be considered when assessing the risk of crop allele introgression into wild populations following hybridization. Although research in cultivars has suggested that domestication traits may reduce fecundity under water stress as compared to wild-like phenotypes, this has not been investigated in crop-wild hybrids. In this study, we examine phenotypic selection acting on, as well as the genetic architecture of vegetative, reproductive, and physiological characteristics in an experimental population of sunflower crop-wild hybrids grown under wild-like low water conditions. Crop-derived petiole length and head diameter were favored in low and control water environments. The direction of selection differed between environments for leaf size and leaf pressure potential. Interestingly, the additive effect of the crop-derived allele was in the direction favored by selection for approximately half the QTL detected in the low water environment. Selection favoring crop-derived traits and alleles in the low water environment suggests that a subset of these alleles would be likely to spread into wild populations under water stress. Furthermore, differences in selection between environments support the view that risk assessments should be conducted under multiple locally relevant conditions.

  14. Effects of different mycorrhiza species on grain yield, nutrient uptake and oil content of sunflower under water stress

    Directory of Open Access Journals (Sweden)

    Mostafa Heidari

    2014-01-01

    Full Text Available The role of arbuscular mycorrhizal fungi in alleviating water stress is well documented. In order to study the effects of water stress and two different mycorrhiza species on grain yield, nutrient uptake and oil content of sunflower, a field experiment as split plot design with three replications was conducted in the Research Field Station, Zabol University, Zabol, Iran in 2011. Water stress treatments included control as 90% of field capacity (W1, 70% field capacity (W2 and 50% field capacity (W3 assigned to the main plots and two different mycorrhiza species, consisting of M1 = control (without any inoculation, M2 = Glumus mossea and M3 = Glumus etanicatum as sub plots. Results showed that by increasing water stress from control (W1 to W3 treatment, grain yield was significantly decreased. The reduction in the level of W3 was 15.05%. The content of potassium in seeds significantly decreased due to water stress but water stress upto W2 treatment increased the content of phosphorus, nitrogen and oil content of seeds. In between two species of mycorrhiza in sunflower plants, Glumus etanicatum had the highest effect on grain yield and these elements in seeds and increased both.

  15. De novo sequencing of sunflower genome for SNP discovery using RAD (Restriction site Associated DNA) approach

    National Research Council Canada - National Science Library

    Pegadaraju, Venkatramana; Nipper, Rick; Hulke, Brent; Qi, Lili; Schultz, Quentin

    2013-01-01

    Application of Single Nucleotide Polymorphism (SNP) marker technology as a tool in sunflower breeding programs offers enormous potential to improve sunflower genetics, and facilitate faster release of sunflower hybrids to the market place...

  16. Comparative potential of Rhizobium species for the growth promotion of sunflower (Helianthus annuus L.

    Directory of Open Access Journals (Sweden)

    Sana Ullah

    2017-07-01

    Full Text Available Rhizobium besides its nodule formation characteristic with members of Fabaceae family has been recognized for its great root colonizing ability and growth hormone production potential. In addition to nitrogen fixation in legume plants, rhizobia considered as beneficial tools and act as plant growth promoting rhizobacteria (PGPR with many non-legumes. Present study was elucidated to determine the comparative role of Rhizbium sp for growth promotion of sunflower. Rhizobia were isolated from five different legumes (mungbean, barseem, lentil, chickpea, and vegetable pea and checked for their auxin production efficiency. Rhizobial isolates Cp-4 showed maximum auxin potential (5.37 µg mL-1IAA equivalents.Results showed that inoculation of all rhizobial isolates caused significant increase in growth and physiological parameters of sunflower plants. While prominent results were found with inoculation of mungbean rhizobial isolate Mb-2 which increases the chlorophyll a, N, P, fresh and dry matter of sunflower significantly by 8.34, 4.9, 36, 31, and 34%, respectively in comparison to un-inoculated control plants. Hence, present study concluded that Rhizobium sp can be successfully used as PGPR in non-legumes after thorough investigations.

  17. Sunflower breeding for resistance to Fusarium

    OpenAIRE

    Gontcharov S.V.; Antonova T.S.; Saukova S.L.

    2006-01-01

    Fusarium fungi have grown from a minor pathogen of sunflower crop to a major problem of sunflowers in Russia. The aim of this work was breeding for resistance to this new major pathogen, combining field and laboratory testing in the framework of VNIIMK hybrid sunflower breeding program. Four segregated hybrid combinations selected on the basis of their field resistance to different pathogens were used as breeding material. Three of them were doublecross combinations: F3 R-14 × (VK-591 × VK-53...

  18. Utilization of sunflower crop wild relatives for cultivated sunflower improvement

    Science.gov (United States)

    Sunflower (Helianthus annuus L.) is one of the few crops native to the U.S. The current USDA-ARS-NPGS crop wild relatives sunflower collection is the largest extant collection in the world, containing 2,519 accessions comprised of 53 species; 39 perennial and 14 annual. To fully utilize gene bank co...

  19. RESULTS CONCERNING THE MELLIFEROUS CHARACTERISTICS OF THE SUNFLOWER HYBRIDS CULTIVATED IN ROMANIA

    Directory of Open Access Journals (Sweden)

    NICOLETA ION

    2007-10-01

    Full Text Available The present paper presents the melliferous characteristics of thirty three sunflowerhybrids studied in the period 2002-2006 in South Romania. The studied hybridswere the following: Festiv, Florom 350, Alex, Romina, Performer, Turbo, Favorit,Justin, Splendor, Trajano, Hercule, Felix, Select and 20 being foreign hybrids(Melody, Sunko, Sanay, Kasol, NK Dolbi, NK Ferti, NK Armoni, Opera PR, Rigasol,Huracan, Podium, Fleuret OR, Rigasol, OR, Mateol, Lindor, Fly, Arena, Alexandra,Masai, SaxoIn order to evaluate the quantity of sugar per hectare and further the potential yieldof honey per hectare, the nectar secretion (capillaries method, the sugarconcentration of the nectar (refractometer method, the number of flowers per headand the number of plants per hectare were determined during field studies.

  20. Spectacular Sunflowers

    Science.gov (United States)

    McNeece, Molly

    2010-01-01

    In this article, the author illustrates how she shares her love of sunflowers with her kindergarten and first-grade students through an interesting art lesson. Sunflowers are easy to grow, so the author started the lesson four months earlier with inexpensive seed packets. She planted many varieties, but she most likes the colors of the Mexican…

  1. Irrigation of Castor Bean (Ricinus communis L.) and Sunflower (Helianthus annus L.) Plant Species with Municipal Wastewater Effluent: Impacts on Soil Properties and Seed Yield

    OpenAIRE

    Chatzakis, Michalis K.; Tzanakakis, Vasileios A.; Mara, Duncan D.; Angelakis, Andreas N.

    2011-01-01

    The effects of plant species (castor bean (Ricinus communis L.) versus sunflower (Helianthus annus L.)) and irrigation regime (freshwater versus secondary treated municipal wastewater) on soil properties and on seed and biodiesel yield were studied in a three year pot trial. Plant species were irrigated at rates according to their water requirements with either freshwater or wastewater effluent. Pots irrigated with freshwater received commercial fertilizer, containing N, P, and K, applied at ...

  2. Sunflower disease compendium: Sunflower botany

    Science.gov (United States)

    The number one challenge for global sunflower production is diseases. Sunflower is the fifth largest oilseed crop grown in temperate and subtropical areas in 72 countries and on every continent, except Antarctica. This has facilitated the spread of diseases globally. Disease control can be by chemic...

  3. Stability estimation for seed and oil yield of NS sunflower hybrids in small-plot trials and recommendations for 2010 sowing season

    Directory of Open Access Journals (Sweden)

    Miklič Vladimir

    2010-01-01

    Full Text Available The objective of this study was the evaluation of NS sunflower hybrids based on the results of seed yield, oil content and oil yield obtained in a network of small-plot trials in Vojvodina and central Serbia in 2009, as well as recommendations for 2010 sowing season. The hybrid location interaction was evaluated by AMMI model (Additive Main Effects and Multiplicative Interaction. In small plot trials, 19 NS sunflower hybrids on 11 locations in Vojvodina and 3 in central Serbia were included. Seed yield, oil content and oil yield were significantly different in the small-plot trials in the investigated regions. The highest average seed yields in Vojvodina were produced by Duško (3.75 t ha-1, Novosađanin (3.74 t ha-1, Kazanova (3.66 t ha-1, Sremac (3.62 t ha-1, Pobednik (3.59 t ha-1 and NS-H-111 (3.57 t ha-1. In the region of central Serbia seed yield over 3.50 t ha-1 was achieved by the hybrids Branko (3.57 t ha-1 and Duško (3.53 t ha-1. Hybrid Pobednik showed the highest average oil content in the region of Vojvodina (49.37 %, as well as in the region of central Serbia (49.96 %. Highest average oil yield (over 1.70 t ha-1 was produced by Pobednik, Novosađanin, NS-H-111 and Somborac in the Vojvodina region, and in central Serbia oil yield (over 1.60 t ha-1 was produced by Branko and Duško. In three-year trials in Vojvodina, eight hybrids (Duško, Kazanova, Sremac, Velja, Baća, Novosađanin, NS-H-111 and Pobednik showed seed yield over general mean. Highest seed yield was given by hybrid Duško (3.63 t ha-1. AMMI biplot for seed yield showed that hybrids Duško, Novosađanin and NS-H-111 had the highest adaptability at all locations (Region Vojvodina and central Serbia, because the interaction had the lowest values. Pobednik and NS-H-111 showed the highest stability for oil content over all locations. The lowest interaction effects for oil yield were found with Duško and NS-H-111. The hybrid NS-H-111, with average mean value over general

  4. Variability in sunflower oil quality for biodiesel production: A simulation study

    Energy Technology Data Exchange (ETDEWEB)

    Pereyra-Irujo, Gustavo A.; Izquierdo, Natalia G.; Quiroz, Facundo; Aguirrezabal, Luis A.N. [Unidad Integrada Balcarce, Facultad de Ciencias Agrarias, Universidad Nacional de Mar del Plata, Instituto Nacional de Tecnologia Agropecuaria, CC 276, 7620 Balcarce, Buenos Aires (Argentina); Covi, Mauro [Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Intendente Gueiraldes 2160, Ciudad Universitaria, C1428EGA, Buenos Aires (Argentina); Nolasco, Susana M. [Facultad de Ingenieria, Universidad Nacional del Centro de la Provincia de Buenos Aires, Avda. del Valle 7537, B7400JWI, Olavarria (Argentina)

    2009-03-15

    Biodiesel is an alternative fuel made from vegetable oils or animal fats. The fatty acid composition of the feedstock, which varies among and within species, is the main determinant of biodiesel quality. In this work we analyze the variability in biodiesel quality (density, kinematic viscosity, heating value, cetane number and iodine value) obtained from sunflower oil, by means of a validated crop model that predicts the fatty acid composition of one high-oleic, and three traditional (high-linoleic) sunflower hybrids. The model was run with a 10-year average weather data from 56 weather stations in Argentina, and simulation results were compared to the biodiesel standards of Argentina, USA and Europe. We show that biodiesel produced from sunflower oil does not have one fixed quality, but different qualities depending on weather conditions and agricultural practices, and that intraspecific variation in biodiesel quality can be larger than interspecific differences. Our results suggest that (a) sunflower oil from high-oleic hybrids is suitable for biodiesel production (within limits of all analyzed standards), regardless of growing conditions and (b) sunflower oil from traditional hybrids is suitable for biodiesel production under the standards of Argentina and USA, while only certain hybrids grown in warm regions (e.g., Northern Argentina, Southern USA, China, India, Pakistan) are suitable for biodiesel production according to the European standard. (author)

  5. [Polymorphism and inheritance of seed storage protein in sunflower].

    Science.gov (United States)

    Anisimova, I N; Gavrilova, V A; Loskutov, A V; Rozhkova, V T; Tolmachev, V V

    2004-09-01

    The data on polymorphism and inheritance of the seed storage protein helianthinin are presented. The results of hybrid analysis indicate that in the annual sunflower Helianthus annuus, helianthinin synthesis is controlled by at least three loci: HelA, HelB, HelB, and HelC. Codominant alleles controlling different electrophoretic variants of polypeptides were identified at each of the loci. The HelA locus was inherited independently of HelB and HelC in a series of dihybrid crosses. The frequencies of recombination between loci HelB and HelC estimated in F2 and BC of two crossing combinations were respectively 21.8 and 19.0%. Segregation of the Hel-C-controlled variants in the progenies from the crosses of cultured sunflower with annual wild species and forms corresponded to that theoretically expected for Mendelian inheritance. The maternal type of helianthinin inheritance was observed in the progenies from the crosses of inbred H. annuus lines with perennial diploid and polyploid Helianthus species. Altered expression of the HelC locus was detected in some hybrid combinations. These alterations appeared in early (F1, F2) hybrid generations and were similar in different hybrid combinations. They did not depend on the perennial paternal species being more influenced by the maternal genotype and by the mode of obtaining hybrids (in an embryo culture or in the field). These results are explained by "genomic shock" generated by hybridization of genetically incompatible species.

  6. Storage of sunflower seeds

    Directory of Open Access Journals (Sweden)

    Denise de Castro Lima

    Full Text Available The sunflower is among the top five crops in the world for the production of edible vegetable oil. The species displays rustic behavior, with an excellent edaphic and climatic adaptability index, being able to be cultivated throughout Brazil. Seed quality is the key to increasing production and productivity in the sunflower. The objective of this work was to monitor the viability of sunflower seeds with a view to their conservation when stored in different environments and packaging. The seeds were packed in paper bags, multilayered paper, black polyethylene and PET bottles; and stored for a period of twelve months in the following environments: dry cold room (10 ºC and 55% RH, the ambient conditions of Fortaleza, Ceará, Brazil (30-32 ºC and 75% RH, refrigerator (4 ºC and 38-43% RH and freezer (-20 ºC. Every three months, the water content of the seeds was determined and germination, accelerated ageing, speed of emergence index, and seedling dry weight were evaluated. The experimental design was completely randomized, in a scheme of split-lots, with four replications. It can be concluded that the natural environment is not suitable for the storage of sunflower seeds. Sunflower seeds remain viable for 12 months when stored in a dry cold room, refrigerator or freezer, irrespective of the type of packaging used.

  7. Resolving incongruence: Species of hybrid origin in Columnea (Gesneriaceae).

    Science.gov (United States)

    Smith, James F; Clark, John L; Amaya-Márquez, Marisol; Marín-Gómez, Oscar H

    2017-01-01

    Speciation by hybridization has long been recognized among plants and includes both homoploid and allopolyploid speciation. The numbers of presumed hybrid species averages close to 11% and tends to be concentrated in a subset of angiosperm families. Recent advances in molecular methods have verified species of hybrid origin that had been presumed on the basis of morphology and have identified species that were not initially considered hybrids. Identifying species of hybrid origin is often a challenge and typically based on intermediate morphology, or discrepancies between molecular datasets. Discrepancies between data partitions may result from several factors including poor support, incomplete lineage sorting, or hybridization. A phylogenetic analysis of species in Columnea (Gesneriaceae) indicated significant incongruencies between the cpDNA and nrDNA datasets. Tests that examined whether one or both of the datasets had the phylogenetic signal to reject the topology of the alternate dataset (Shimodaira and Hasegawa [SH] and approximately unbiased [AU] tests) indicated significant differences between the topologies. Splitstree analyses also showed that there was support for the placement of the discrepant taxa in both datasets and that the combined data placed the putative hybrid species in an intermediate position between the two datasets. The genealogical sorting index (GSI) implied that coalescence in nrDNA had occurred in all species where more than a single individual had been sampled, but the GSI value was lower for the cpDNA of most of the putative hybrids, implying that these regions have not yet coalesced in these lineages despite being haploid. The JML test that evaluates simulated species pairwise distances against observed distances also implies that observed nrDNA data generate shorter distances than simulated data, implying hybridization. It is most likely that C. gigantifolia, C. rubriacuta, and C. sp. nov. represent a lineage from a hybrid ancestor

  8. Relative susceptibility of sunflower maintainer lines and resistance sources to natural infestations of the banded sunflower moth (Lepidoptera: Tortricidae)

    Science.gov (United States)

    The banded sunflower moth, Cochylis hospes Walsingham (Lepidoptera: Tortricidae), is a significant seed-feeding pest of sunflowers in North America. Though some wild Helianthus spp., interspecific crosses, and H. annuus cultivars (that precede hybrid sunflower breeding) have low susceptibility to ba...

  9. Agronomic characteristic of a dwarf germplasm sunflower line

    OpenAIRE

    Vassilevska-Ivanova Roumiana; Tcekova Zoja

    2005-01-01

    A new sunflower (Helianthus annuus L) dwarf line, HA-ARG-1, has been developed after interspecific hybridization between cultivated sunflower H. annuus and wild annual silver-leaf sunflower H. argophyllus. Plants were selected for reduced height and multiple branching characteristics. The agronomic, morphologic and oil content characteristics of the line were analyzed. Isolation of similar dwarfed lines illustrates the importance of using the wild sunflower germplasms in the development of sp...

  10. Nitrogen stress response of a hybrid species: a gene expression study.

    Science.gov (United States)

    Brouillette, Larry C; Donovan, Lisa A

    2011-01-01

    Low soil fertility limits growth and productivity in many natural and agricultural systems, where the ability to sense and respond to nutrient limitation is important for success. Helianthus anomalus is an annual sunflower of hybrid origin that is adapted to desert sand-dune substrates with lower fertility than its parental species, H. annuus and H. petiolaris. Previous studies have shown that H. anomalus has traits generally associated with adaptation to low-fertility habitats, including a lower inherent relative growth rate and longer leaf lifetime. Here, a cDNA microarray is used to identify gene expression differences that potentially contribute to increased tolerance of low fertility of the hybrid species by comparing the nitrogen stress response of all three species with high- and low-nutrient treatments. Relative to the set of genes on the microarray, the genes showing differential expression in the hybrid species compared with its parents are enriched in stress-response genes, developmental genes, and genes involved in responses to biotic or abiotic stimuli. After a correction for multiple comparisons, five unique genes show a significantly different response to nitrogen limitation in H. anomalus compared with H. petiolaris and H. annuus. The Arabidopsis thaliana homologue of one of the five genes, catalase 1, has been shown to affect the timing of leaf senescence, and thus leaf lifespan. The five genes identified in this analysis will be examined further as candidate genes for the adaptive stress response in H. anomalus. Genes that improve growth and productivity under nutrient stress could be used to improve crops for lower soil fertility which is common in marginal agricultural settings.

  11. Irrigation of Castor Bean (Ricinus communis L. and Sunflower (Helianthus annus L. Plant Species with Municipal Wastewater Effluent: Impacts on Soil Properties and Seed Yield

    Directory of Open Access Journals (Sweden)

    Vasileios A. Tzanakakis

    2011-11-01

    Full Text Available The effects of plant species (castor bean (Ricinus communis L. versus sunflower (Helianthus annus L. and irrigation regime (freshwater versus secondary treated municipal wastewater on soil properties and on seed and biodiesel yield were studied in a three year pot trial. Plant species were irrigated at rates according to their water requirements with either freshwater or wastewater effluent. Pots irrigated with freshwater received commercial fertilizer, containing N, P, and K, applied at the beginning of each irrigation period. The results obtained in this study showed that irrigation with effluent did not result in significant changes in soil pH, soil organic matter (SOM, total kjeldahl nitrogen (TKN, and dehydrogenase activity, whereas soil available P was found to increase in the upper soil layer. Soil salinity varied slightly throughout the experiment in effluent irrigated pots but no change was detected at the end of the experiment compared to the initial value, suggesting sufficient salt leaching. Pots irrigated with effluent had higher soil salinity, P, and dehydrogenase activity but lower SOM and TKN than freshwater irrigated pots. Sunflower showed greater SOM and TKN values than castor bean suggesting differences between plant species in the microorganisms carrying out C and N mineralization in the soil. Plant species irrigated with freshwater achieved higher seed yield compared to those irrigated with effluent probably reflecting the lower level of soil salinity in freshwater irrigated pots. Castor bean achieved greater seed yield than sunflower. Biodiesel production followed the pattern of seed yield. The findings of this study suggest that wastewater effluent can constitute an important source of irrigation water and nutrients for bioenergy crop cultivations with minor adverse impacts on soil properties and seed yield. Plant species play an important role with regard to the changes in soil properties and to the related factors of

  12. POLLEN TRANSFER BY NATURAL HYBRIDS AND PARENTAL SPECIES IN AN IPOMOPSIS HYBRID ZONE.

    Science.gov (United States)

    Campbell, Diane R; Waser, Nickolas M; Wolf, Paul G

    1998-12-01

    Models of hybrid zones differ in their assumptions about the relative fitnesses of hybrids and the parental species. These fitness relationships determine the form of selection across the hybrid zone and, along with gene flow, the evolutionary dynamics and eventual outcome of natural hybridization. We measured a component of fitness, export and receipt of pollen in single pollinator visits, for hybrids between the herbaceous plants Ipomopsis aggregata and I. tenuituba and for both parental species. In aviary experiments with captive hummingbirds, hybrid flowers outperformed flowers of both parental species by receiving more pollen on the stigma. Although hummingbirds were more effective at removing pollen from anthers of I. aggregata, hybrid flowers matched both parental species in the amount of pollen exported to stigmas of other flowers. These patterns of pollen transfer led to phenotypic stabilizing selection, during that stage of the life cycle, for a stigma position intermediate between that of the two species and to directional selection for exserted anthers. Pollen transfer between the species was high, with flowers of I. aggregata exporting pollen equally successfully to conspecific and I. tenuituba flowers. Although this study showed that natural hybrids enjoy the highest quality of pollinator visits, a previous study found that I. aggregata receives the highest quantity of pollinator visits. Thus, the relative fitness of hybrids changes over the life cycle. By combining the results of both studies, pollinator-mediated selection in this hybrid zone is predicted to be strong and directional, with hybrid fitness intermediate between that of the parental species. © 1998 The Society for the Study of Evolution.

  13. Bidirectional introgressive hybridization between a cattle and human schistosome species.

    Directory of Open Access Journals (Sweden)

    Tine Huyse

    2009-09-01

    Full Text Available Schistosomiasis is a disease of great medical and veterinary importance in tropical and subtropical regions, caused by parasitic flatworms of the genus Schistosoma (subclass Digenea. Following major water development schemes in the 1980s, schistosomiasis has become an important parasitic disease of children living in the Senegal River Basin (SRB. During molecular parasitological surveys, nuclear and mitochondrial markers revealed unexpected natural interactions between a bovine and human Schistosoma species: S. bovis and S. haematobium, respectively. Hybrid schistosomes recovered from the urine and faeces of children and the intermediate snail hosts of both parental species, Bulinus truncatus and B. globosus, presented a nuclear ITS rRNA sequence identical to S. haematobium, while the partial mitochondrial cox1 sequence was identified as S. bovis. Molecular data suggest that the hybrids are not 1st generation and are a result of parental and/or hybrid backcrosses, indicating a stable hybrid zone. Larval stages with the reverse genetic profile were also found and are suggested to be F1 progeny. The data provide indisputable evidence for the occurrence of bidirectional introgressive hybridization between a bovine and a human Schistosoma species. Hybrid species have been found infecting B. truncatus, a snail species that is now very abundant throughout the SRB. The recent increase in urinary schistosomiasis in the villages along the SRB could therefore be a direct effect of the increased transmission through B. truncatus. Hybridization between schistosomes under laboratory conditions has been shown to result in heterosis (higher fecundity, faster maturation time, wider intermediate host spectrum, having important implications on disease prevalence, pathology and treatment. If this new hybrid exhibits the same hybrid vigour, it could develop into an emerging pathogen, necessitating further control strategies in zones where both parental species

  14. Neo-sex chromosome inheritance across species in Silene hybrids.

    Science.gov (United States)

    Weingartner, L A; Delph, L F

    2014-07-01

    Neo-sex chromosomes, which form through the major restructuring of ancestral sex chromosome systems, have evolved in various taxa. Such restructuring often consists of the fusion of an autosome to an existing sex chromosome, resulting in novel sex chromosome formations (e.g. X1X2Y or XY1Y2.). Comparative studies are often made between restructured sex chromosome systems of closely related species, and here we evaluate the consequences of variable sex chromosome systems to hybrids. If neo-sex chromosomes are improperly inherited across species, this could lead to aberrant development and reproductive isolation. In this study, we examine the fate of neo-sex chromosomes in hybrids of the flowering plants Silene diclinis and Silene latifolia. Silene diclinis has a neo-sex chromosome system (XY1Y2) that is thought to have evolved from an ancestral XY system that is still present in S. latifolia. These species do not hybridize naturally, and improper sex chromosome inheritance could contribute to reproductive isolation. We investigated whether this major restructuring of sex chromosomes prevents their proper inheritance in a variety of hybrid crosses, including some F2 - and later-generation hybrids, with sex chromosome-linked, species-specific, polymorphic markers and chromosome squashes. We discovered that despite the differences in sex chromosomes that exist between these two species, proper segregation had occurred in hybrids that made it to flowering, including later-generation hybrids, indicating that neo-sex chromosome formation alone does not result in complete reproductive isolation between these two species. Additionally, hybrids with aberrant sex expression (e.g. neuter, hermaphrodite) also inherited the restructured sex chromosomes properly, highlighting that issues with sexual development in hybrids can be caused by intrinsic genetic incompatibility rather than improper sex chromosome inheritance. © 2014 The Authors. Journal of Evolutionary Biology © 2014

  15. Bidirectional introgressive hybridization between a cattle and human schistosome species.

    Science.gov (United States)

    Huyse, Tine; Webster, Bonnie L; Geldof, Sarah; Stothard, J Russell; Diaw, Oumar T; Polman, Katja; Rollinson, David

    2009-09-01

    Schistosomiasis is a disease of great medical and veterinary importance in tropical and subtropical regions, caused by parasitic flatworms of the genus Schistosoma (subclass Digenea). Following major water development schemes in the 1980s, schistosomiasis has become an important parasitic disease of children living in the Senegal River Basin (SRB). During molecular parasitological surveys, nuclear and mitochondrial markers revealed unexpected natural interactions between a bovine and human Schistosoma species: S. bovis and S. haematobium, respectively. Hybrid schistosomes recovered from the urine and faeces of children and the intermediate snail hosts of both parental species, Bulinus truncatus and B. globosus, presented a nuclear ITS rRNA sequence identical to S. haematobium, while the partial mitochondrial cox1 sequence was identified as S. bovis. Molecular data suggest that the hybrids are not 1st generation and are a result of parental and/or hybrid backcrosses, indicating a stable hybrid zone. Larval stages with the reverse genetic profile were also found and are suggested to be F1 progeny. The data provide indisputable evidence for the occurrence of bidirectional introgressive hybridization between a bovine and a human Schistosoma species. Hybrid species have been found infecting B. truncatus, a snail species that is now very abundant throughout the SRB. The recent increase in urinary schistosomiasis in the villages along the SRB could therefore be a direct effect of the increased transmission through B. truncatus. Hybridization between schistosomes under laboratory conditions has been shown to result in heterosis (higher fecundity, faster maturation time, wider intermediate host spectrum), having important implications on disease prevalence, pathology and treatment. If this new hybrid exhibits the same hybrid vigour, it could develop into an emerging pathogen, necessitating further control strategies in zones where both parental species overlap.

  16. Monoterpene alcohols release and bioconversion by Saccharomyces species and hybrids.

    Science.gov (United States)

    Gamero, A; Manzanares, P; Querol, A; Belloch, C

    2011-01-31

    Terpene profile of Muscat wines fermented by Saccharomyces species and hybrid yeasts was investigated. The amount of geraniol decreased in most wines with respect to the initial must except for Saccharomyces bayanus wines. On the other hand, alpha-terpineol amount was higher in wines fermented by Saccharomyces cerevisiae and hybrid yeasts. The amount of linalool was similar in all wines and comparable to the amount in the initial must. Lower levels of beta-D-glucosidase activity were found in the hybrid yeasts with respect to S. cerevisiae. Moreover, no relationship between beta-D-glucosidase activity and terpenes profile in Muscat wines fermented with Saccharomyces species and hybrids was found. Growth of yeasts on minimum medium supplemented with geraniol showed bioconversion of geraniol into linalool and alpha-terpineol. Percentages of geraniol uptake and bioconversion were different between Saccharomyces species and hybrids. Strains within S. bayanus, Saccharomyces kudriavzevii and hybrids showed higher geraniol uptake than S. cerevisiae, whereas the percentage of produced linalool and alpha-terpineol was higher in S. cerevisiae and hybrid yeasts than in S. bayanus and S. kudriavzevii. The relationship between geraniol uptake and adaptation of Saccharomyces species to grow at low temperature is discussed. Copyright © 2010 Elsevier B.V. All rights reserved.

  17. Variability in oil tocopherol concentration and composition of traditional and high oleic sunflower hybrids (Helianthus annuus L. in the Pampean region (Argentina

    Directory of Open Access Journals (Sweden)

    Mateo, Carmen

    2006-09-01

    Full Text Available Tocopherols are natural antioxidants that increase the stability of food fat and fulfill an important biological requirement in humans. There are no previous studies on the variability of tocopherol concentration and composition in the oil of sunflower traditional hybrids (TH and high oleic sunflower hybrids (HOH from different environments in Argentina. The objective of this work was to detect and  examine that variability. Seed samples were obtained from i seven TH grown in four locations (Experiment I and, ii five hybrids (three HOH and two traditional ones grown in three locations (Experiment II. Concentrations of total tocopherol in oil ranged from 634 to 1054 μg g oil–1. α-tocopherol accounted for 90.8 to 97% of the total tocopherols. Total and α-tocopherol concentrations were highly genetically determined (more than 80%. In Experiment I, a significant, although low in value, interaction between hybrid and location was found for total and α-tocopherol concentrations. In Experiment II, mean values for total tocopherol concentration in HOH and in each environment were larger than in TH. Significant differences for total and α-tocopherol concentration were not found among HOH and environments. The variation of tocopherol concentration for each hybrid across environments was higher than the variation among hybrids in the same environment. To obtain oil with high tocopherol concentration, both hybrid and environment must be selected.Los tocoferoles son antioxidantes naturales que aumentan la estabilidad de los aceites y cumplen una importante actividad biológica en humanos. No son conocidos estudios sobre la variabilidad del contenido y composición de tocoferoles en el aceite de híbridos de girasol tradicionales (HT y “alto oleico” (HAO sembrados en diferentes ambientes en Argentina. El objetivo de este trabajo fue detectar y examinar esa variabilidad. Las semillas fueron obtenidas de a 7 HT sembrados en 4 localidades

  18. Sunflower (Helianthus annuus L.).

    Science.gov (United States)

    Radonic, Laura M; Lewi, Dalia M; López, Nilda E; Hopp, H Esteban; Escandón, Alejandro S; Bilbao, Marisa López

    2015-01-01

    Sunflower (Helianthus annuus L.) is still considered as a recalcitrant species to in vitro culture and transformation in spite of the publication of different protocols. Here we describe a routine transformation system of this crop which requires mature HA89 genotype seeds and Agrobacterium tumefaciens EHA105 strain for gene delivery, being both easily available. Selection of transformed shoots depends on root development in kanamycin-selective media, instead of shoot color, avoiding selection of escapes. The establishment of this protocol proved successful for the incorporation of both reporter and agronomic important genes and also for the evaluation of the specific expression patterns of different promoters in transgenic sunflower plants. Stable expression of the incorporated transgenes was confirmed by RT-PCR and GUS reporter gene visualization. Stable inheritance of transgenes was successfully followed until T2 generation in several independent lines.

  19. Fine mapping of the sunflower resistance locus Pl(ARG) introduced from the wild species Helianthus argophyllus.

    Science.gov (United States)

    Wieckhorst, S; Bachlava, E; Dussle, C M; Tang, S; Gao, W; Saski, C; Knapp, S J; Schön, C-C; Hahn, V; Bauer, E

    2010-11-01

    Downy mildew, caused by Plasmopara halstedii, is one of the most destructive diseases in cultivated sunflower (Helianthus annuus L.). The dominant resistance locus Pl(ARG) originates from silverleaf sunflower (H. argophyllus Torrey and Gray) and confers resistance to all known races of P. halstedii. We mapped Pl(ARG) on linkage group (LG) 1 of (cms)HA342 × ARG1575-2, a population consisting of 2,145 F(2) individuals. Further, we identified resistance gene candidates (RGCs) that cosegregated with Pl(ARG) as well as closely linked flanking markers. Markers from the target region were mapped with higher resolution in NDBLOS(sel) × KWS04, a population consisting of 2,780 F(2) individuals that does not segregate for Pl(ARG). A large-insert sunflower bacterial artificial chromosome (BAC) library was screened with overgo probes designed for markers RGC52 and RGC151, which cosegregated with Pl(ARG). Two RGC-containing BAC contigs were anchored to the Pl(ARG) region on LG 1.

  20. Fine mapping of the sunflower resistance locus PlARG introduced from the wild species Helianthus argophyllus

    Science.gov (United States)

    Wieckhorst, S.; Bachlava, E.; Dußle, C. M.; Tang, S.; Gao, W.; Saski, C.; Knapp, S. J.; Schön, C.-C.; Hahn, V.

    2010-01-01

    Downy mildew, caused by Plasmopara halstedii, is one of the most destructive diseases in cultivated sunflower (Helianthus annuus L.). The dominant resistance locus PlARG originates from silverleaf sunflower (H. argophyllus Torrey and Gray) and confers resistance to all known races of P. halstedii. We mapped PlARG on linkage group (LG) 1 of (cms)HA342 × ARG1575-2, a population consisting of 2,145 F2 individuals. Further, we identified resistance gene candidates (RGCs) that cosegregated with PlARG as well as closely linked flanking markers. Markers from the target region were mapped with higher resolution in NDBLOSsel × KWS04, a population consisting of 2,780 F2 individuals that does not segregate for PlARG. A large-insert sunflower bacterial artificial chromosome (BAC) library was screened with overgo probes designed for markers RGC52 and RGC151, which cosegregated with PlARG. Two RGC-containing BAC contigs were anchored to the PlARG region on LG 1. Electronic supplementary material The online version of this article (doi:10.1007/s00122-010-1416-4) contains supplementary material, which is available to authorized users. PMID:20700574

  1. Reproductive characterization of interspecific hybrids among Capsicum species

    Directory of Open Access Journals (Sweden)

    Carlos Eduardo da Silva Monteiro

    2011-01-01

    Full Text Available The objective of this study was the reproductive characterization of Capsicum accessions as well as of interspecifichybrids, based on pollen viability. Hybrids were obtained between Capsicum species. Pollen viability was high in most accessions,indicating that meiosis is normal, resulting in viable pollen grains. The pollen viability of species C. pubescens was the lowest (27%. The interspecific hybrids had varying degrees of pollen viability, from fertile combinations (C. chinense x C. frutescens and C.annuum x C. baccatum to male sterile combinations. Pollen viability also varied within the hybrid combination according toaccessions used in the cross. Results indicate that male sterility is one of the incompatibility barriers among Capsicum species sincehybrids can be established, but may be male sterile.

  2. Selection on Crop-Derived Traits and QTL in Sunflower (Helianthus annuus) Crop-Wild Hybrids under Water Stress

    OpenAIRE

    Owart, Birkin R.; Jonathan Corbi; John M Burke; Jennifer M Dechaine

    2014-01-01

    Locally relevant conditions, such as water stress in irrigated agricultural regions, should be considered when assessing the risk of crop allele introgression into wild populations following hybridization. Although research in cultivars has suggested that domestication traits may reduce fecundity under water stress as compared to wild-like phenotypes, this has not been investigated in crop-wild hybrids. In this study, we examine phenotypic selection acting on, as well as the genetic architect...

  3. Inheritance of reduced saturated fatty acid content in sunflower oil

    OpenAIRE

    Vick Brady A.; Jan C.C.; Miller Jerry F.

    2002-01-01

    In recent years, consumers have become concerned with reducing the saturated fat content of their diet. Studies have indicated that high levels of saturated fat consumption are correlated with increased risk of coronary heart disease. The total saturated fat content of oil from current sunflower hybrids averages about 130 g kg-1. To identify sunflower germplasm with reduced saturated fatty acid composition, a total of 884 cultivated sunflower accessions from the USDA-ARS North Central Regiona...

  4. Introgressive hybridization of Schistosoma haematobium group species in Senegal: species barrier break down between ruminant and human schistosomes

    National Research Council Canada - National Science Library

    Webster, Bonnie L; Diaw, Oumar T; Seye, Mohmoudane M; Webster, Joanne P; Rollinson, David

    2013-01-01

    .... Schistosomes undergo a sexual reproductive stage within their mammalian host enabling interactions between different species, which may result in hybridization if the species involved are phylogenetically close...

  5. Seed yield and protein content in sunflower depending on stand density

    Directory of Open Access Journals (Sweden)

    Balalić Igor M.

    2016-01-01

    Full Text Available The aim of this research was to investigate the effect of stand density on seed yield and protein content in sunflower hybrids. The field experiment was carried out at Rimski Šančevi location. Six NS sunflower hybrids were examined. Five hybrids are confectionery (NS Goliat, NS Slatki, NS Gricko, Vranac and Cepko, and one is used for bird food (NS-H-6485. The trial was arranged as randomized complete block design (RCBD with four replications. Sowing was done with six different densities (from 20,000 to 70,000 plants per hectare, with an increment of 10,000 plants per hectare. Analysis of variance (ANOVA showed that the effect of hybrid, stand density and hybrid × stand density interation were highly significant for seed yield and protein content. The highest seed yield, on the basis of average for all densities, was found in NS-H-6485 (4.77 t ha-1 and in NS Gricko (4.43 t ha-1. Average seed yield of hybrids significantly increased up to 50,000 plants per ha-1, when it reached the value of 4.50 t ha-1, and then decreased. Significantly higher protein content, taking into account all stand densities, showed hybrid Cepko (16.94%. Protein content, above the overall average value, was achieved in hybrid Vranac (16.11%. The high­est protein content in the average for all six hybrids was at the lowest stand density (20,000 plants per ha-1, and then decreased up to higher densities. The results showed that stand density had significant effect on seed yield and protein content in sunflower hybrids. [Projekat Ministarstva nauke Republike Srbije, br. TR31025: The development of new cultivars and improving the technology of producing oil plant species for different purposes

  6. Analysis of transposons and repeat composition of the sunflower (Helianthus annuus L.) genome.

    Science.gov (United States)

    Cavallini, Andrea; Natali, Lucia; Zuccolo, Andrea; Giordani, Tommaso; Jurman, Irena; Ferrillo, Veronica; Vitacolonna, Nicola; Sarri, Vania; Cattonaro, Federica; Ceccarelli, Marilena; Cionini, Pier Giorgio; Morgante, Michele

    2010-02-01

    A sample-sequencing strategy combined with slot-blot hybridization and FISH was used to study the composition of the repetitive component of the sunflower genome. One thousand six hundred thirty-eight sequences for a total of 954,517 bp were analyzed. The fraction of sequences that can be classified as repetitive using computational and hybridization approaches amounts to 62% in total. Almost two thirds remain as yet uncharacterized in nature. Of those characterized, most belong to the gypsy superfamily of LTR-retrotransposons. Unlike in other species, where single families can account for large fractions of the genome, it appears that no transposon family has been amplified to very high levels in sunflower. All other known classes of transposable elements were also found. One family of unknown nature (contig 61) was the most repeated in the sunflower genome. The evolution of the repetitive component in the Helianthus genus and in other Asteraceae was studied by comparative analysis of the hybridization of total genomic DNAs from these species to the sunflower small-insert library and compared to gene-based phylogeny. Very little similarity is observed between Helianthus species and two related Asteraceae species outside of the genus. Most repetitive elements are similar in annual and perennial Helianthus species indicating that sequence amplification largely predates such divergence. Gypsy-like elements are more represented in the annuals than in the perennials, while copia-like elements are similarly represented, attesting a different amplification history of the two superfamilies of LTR-retrotransposons in the Helianthus genus.

  7. Multivariate Numerical Taxonomy of Mentha Species, Hybrids, Varieties and Cultivars

    OpenAIRE

    ŠARIĆ-KUNDALIĆ, Broza; FIALOVÁ, Silvia; Dobeš, Christoph; ÖLZANT, Silvester; TEKEĽOVÁ, Daniela; GRANČAI, Daniel; Reznicek, Gottfried; Saukel, Johannes

    2009-01-01

    Hercegovina and Slovakia is presented. Following a population-based approach and using hierarchical cluster analyses the following basic species and hybrids corresponding to exclusive branches, i.e. groups, in the constructed hierarchies were recognized: Mentha aquatica, M. spicata, M. arvensis, M. longifolia, M. rotundifolia, M. × piperita, M. × villosa, M. × verticillata, M. × gentillis, M. × gracilis and M. pulegium. These groups were independently found by separate analyses of the sampled...

  8. SUNFLOWER SUPPLY INFORMATION

    OpenAIRE

    Gineo, Wayne M.; Sundquist, W. Burt

    1981-01-01

    This report is concerned with a discussion of the sunflower production sector. It summarizes and discusses the North American sunflower production sector in terms of area, acreage, total production, yields and prices. In addition, a preliminary evaluation of the potential level of sunflower production is made.

  9. Van Gogh's Sunflowers

    Science.gov (United States)

    Daddino, Michelle

    2010-01-01

    In this article, the author describes an art project wherein kindergarten students painted sunflowers. These beautiful and colorful sunflowers were inspired by the book "Camille and the Sunflowers" by Laurence Anholt, which does an amazing job of introducing young children to the art and life of Vincent van Gogh.

  10. Leaf traits in parental and hybrid species of Sorbus (Rosaceae).

    Science.gov (United States)

    Durkovic, Jaroslav; Kardosová, Monika; Canová, Ingrid; Lagana, Rastislav; Priwitzer, Tibor; Chorvát, Dusan; Cicák, Alojz; Pichler, Viliam

    2012-09-01

    Knowledge of functional leaf traits can provide important insights into the processes structuring plant communities. In the genus Sorbus, the generation of taxonomic novelty through reticulate evolution that gives rise to new microspecies is believed to be driven primarily by a series of interspecific hybridizations among closely related taxa. We tested hypotheses for dispersion of intermediacy across the leaf traits in Sorbus hybrids and for trait linkages with leaf area and specific leaf area. Here, we measured and compared the whole complex of growth, vascular, and ecophysiological leaf traits among parental (Sorbus aria, Sorbus aucuparia, Sorbus chamaemespilus) and natural hybrid (Sorbus montisalpae, Sorbus zuzanae) species growing under field conditions. A recently developed atomic force microscopy technique, PeakForce quantitative nanomechanical mapping, was used to characterize the topography of cell wall surfaces of tracheary elements and to map the reduced Young's modulus of elasticity. Intermediacy was associated predominantly with leaf growth traits, whereas vascular and ecophysiological traits were mainly parental-like and transgressive phenotypes. Larger-leaf species tended to have lower modulus of elasticity values for midrib tracheary element cell walls. Leaves with a biomass investment related to a higher specific leaf area had a lower density. Leaf area- and length-normalized theoretical hydraulic conductivity was related to leaf thickness. For the whole complex of examined leaf traits, hybrid microspecies were mosaics of parental-like, intermediate, and transgressive phenotypes. The high proportion of transgressive character expressions found in Sorbus hybrids implies that generation of extreme traits through transgressive segregation played a key role in the speciation process.

  11. Detecting hybridization in African schistosome species: does egg morphology complement molecular species identification?

    Science.gov (United States)

    Boon, Nele A M; Fannes, Wouter; Rombouts, Sara; Polman, Katja; Volckaert, Filip A M; Huyse, Tine

    2017-06-01

    Hybrid parasites may have an increased transmission potential and higher virulence compared to their parental species. Consequently, hybrid detection is critical for disease control. Previous crossing experiments showed that hybrid schistosome eggs have distinct morphotypes. We therefore compared the performance of egg morphology with molecular markers with regard to detecting hybridization in schistosomes. We studied the morphology of 303 terminal-spined eggs, originating from 19 individuals inhabiting a hybrid zone with natural crosses between the human parasite Schistosoma haematobium and the livestock parasite Schistosoma bovis in Senegal. The egg sizes showed a high variability and ranged between 92·4 and 176·4 µm in length and between 35·7 and 93·0 µm in width. No distinct morphotypes were found and all eggs resembled, to varying extent, the typical S. haematobium egg type. However, molecular analyses on the same eggs clearly showed the presence of two distinct partial mitochondrial cox1 profiles, namely S. bovis and S. haematobium, and only a single nuclear ITS rDNA profile (S. haematobium). Therefore, in these particular crosses, egg morphology appears not a good indicator of hybrid ancestry. We conclude by discussing strengths and limitations of molecular methods to detect hybrids in the context of high-throughput screening of field samples.

  12. Sunflower (Helinathus annuus L.): A potential crop for environmental industry

    OpenAIRE

    Prasad M.N.V.

    2007-01-01

    Sunflower applications in phytotechnologies for the clean-up of inorganic and organic contaminants and pollutants are reviewed in this compilation. There have been several apprehensions on the application of phytoremediation technology. High bioproductivity and biomass yield are a must for the success of this strategy. The phytoextraction coefficient of sunflowers is high compared with many other species. Sunflower is a proven laboratory and field example for the emerging environmental indust...

  13. Genetics and mapping of the R11 gene conferring resistance to recently emerged rust races, tightly linked to male fertility restoration, in sunflower (Helianthus annuus L.)

    Science.gov (United States)

    Sunflower oil is one of the major sources of edible oil. As the second largest hybrid crop in the world, hybrid sunflowers are developed by using the PET1 cytoplasmic male sterility system that contributes a 20% yield advantage over the open-pollinated varieties. However, sunflower production in Nor...

  14. Paternal Mitochondrial Transmission in Intra-Species Caenorhabditis briggsae Hybrids

    Science.gov (United States)

    Ross, Joseph A.; Howe, Dana K.; Coleman-Hulbert, Anna; Denver, Dee R.; Estes, Suzanne

    2016-01-01

    To study mitochondrial–nuclear genetic interactions in the nematode Caenorhabditis briggsae, our three laboratories independently created 38 intra-species cytoplasmic–nuclear hybrid (cybrid) lines. Although the cross design combines maternal mitotypes with paternal nuclear genotypes, eight lines (21%) unexpectedly contained paternal mitotypes. All eight share in common ancestry of one of two genetically related strains. This unexpected parallel observation of paternal mitochondrial transmission, undesirable given our intent of creating cybrids, provides a serendipitous experimental model and framework to study the molecular and evolutionary basis of uniparental mitochondrial inheritance. PMID:27613821

  15. Introgressive hybridization of Schistosoma haematobium group species in Senegal: species barrier break down between ruminant and human schistosomes.

    Directory of Open Access Journals (Sweden)

    Bonnie L Webster

    Full Text Available BACKGROUND: Schistosomes are dioecious parasitic flatworms, which live in the vasculature of their mammalian definitive hosts. They are the causative agent of schistosomiasis, a disease of considerable medical and veterinary importance in tropical and subtropical regions. Schistosomes undergo a sexual reproductive stage within their mammalian host enabling interactions between different species, which may result in hybridization if the species involved are phylogenetically close. In Senegal, three closely related species in the Schistosoma haematobium group are endemic: S. haematobium, which causes urogenital schistosomiasis in humans, and S. bovis and S. curassoni, which cause intestinal schistosomiasis in cows, sheep and goats. METHODOLOGY/PRINCIPAL FINDINGS: Large-scale multi-loci molecular analysis of parasite samples collected from children and domestic livestock across Senegal revealed that interactions and hybridization were taking place between all three species. Evidence of hybridization between S. haematobium/S. curassoni and S. haematobium/S. bovis was commonly found in children from across Senegal, with 88% of the children surveyed in areas of suspected species overlap excreting hybrid miracidia. No S. haematobium worms or hybrids thereof were found in ruminants, although S. bovis and S. curassoni hybrid worms were found in cows. Complementary experimental mixed species infections in laboratory rodents confirmed that males and females of each species readily pair and produce viable hybrid offspring. CONCLUSIONS/SIGNIFICANCE: THESE DATA PROVIDE INDISPUTABLE EVIDENCE FOR: the high occurrence of bidirectional hybridization between these Schistosoma species; the first conclusive evidence for the natural hybridisation between S. haematobium and S. curassoni; and demonstrate that the transmission of the different species and their hybrids appears focal. Hybridization between schistosomes has been known to influence the disease epidemiology

  16. Introgressive hybridization of Schistosoma haematobium group species in Senegal: species barrier break down between ruminant and human schistosomes.

    Science.gov (United States)

    Webster, Bonnie L; Diaw, Oumar T; Seye, Mohmoudane M; Webster, Joanne P; Rollinson, David

    2013-01-01

    Schistosomes are dioecious parasitic flatworms, which live in the vasculature of their mammalian definitive hosts. They are the causative agent of schistosomiasis, a disease of considerable medical and veterinary importance in tropical and subtropical regions. Schistosomes undergo a sexual reproductive stage within their mammalian host enabling interactions between different species, which may result in hybridization if the species involved are phylogenetically close. In Senegal, three closely related species in the Schistosoma haematobium group are endemic: S. haematobium, which causes urogenital schistosomiasis in humans, and S. bovis and S. curassoni, which cause intestinal schistosomiasis in cows, sheep and goats. Large-scale multi-loci molecular analysis of parasite samples collected from children and domestic livestock across Senegal revealed that interactions and hybridization were taking place between all three species. Evidence of hybridization between S. haematobium/S. curassoni and S. haematobium/S. bovis was commonly found in children from across Senegal, with 88% of the children surveyed in areas of suspected species overlap excreting hybrid miracidia. No S. haematobium worms or hybrids thereof were found in ruminants, although S. bovis and S. curassoni hybrid worms were found in cows. Complementary experimental mixed species infections in laboratory rodents confirmed that males and females of each species readily pair and produce viable hybrid offspring. THESE DATA PROVIDE INDISPUTABLE EVIDENCE FOR: the high occurrence of bidirectional hybridization between these Schistosoma species; the first conclusive evidence for the natural hybridisation between S. haematobium and S. curassoni; and demonstrate that the transmission of the different species and their hybrids appears focal. Hybridization between schistosomes has been known to influence the disease epidemiology and enhance phenotypic characteristics affecting transmission, morbidity and drug

  17. Complete genome sequence of sunflower ring blotch virus, a new potyvirus infecting sunflower in Argentina.

    Science.gov (United States)

    Cabrera Mederos, Dariel; Bejerman, Nicolás; Trucco, Verónica; de Breuil, Soledad; Lenardon, Sergio; Giolitti, Fabián

    2017-06-01

    The complete genome sequence of sunflower ring blotch virus (SuRBV), a previously undescribed potyvirus infecting sunflower in Argentina, is reported. The SuRBV genome comprises 9555 nucleotides (nt) and encodes a polyprotein of 3061 amino acids, flanked by 5' and 3' untranslated regions of 117 and 255 nt, respectively. Phylogenetic analysis showed that SuRBV belongs to the potato virus Y (PVY) subgroup and clusters together with sunflower chlorotic mottle virus and bidens mosaic virus. Percentage nucleotide identity between the whole genomes of SuRBV and BiMV was 70.6%, suggesting SuRBV should be considered a distinct species in the genus Potyvirus.

  18. Comparative Genetics of Hybrid Incompatibility: Sterility in Two Solanum Species Crosses

    OpenAIRE

    Moyle, Leonie C.; Nakazato, Takuya

    2008-01-01

    The genetic basis of hybrid sterility can provide insight into the genetic and evolutionary origins of species barriers. We examine the genetics of hybrid incompatibility between two diploid plant species in the plant clade Solanum sect. Lycopersicon. Using a set of near-isogenic lines (NILs) representing the wild species Solanum pennellii (formerly Lycopersicon pennellii) in the genetic background of the cultivated tomato S. lycopersicum (formerly L. esculentum), we found that hybrid pollen ...

  19. Hybrid-Lambda: simulation of multiple merger and Kingman gene genealogies in species networks and species trees.

    Science.gov (United States)

    Zhu, Sha; Degnan, James H; Goldstien, Sharyn J; Eldon, Bjarki

    2015-09-15

    There has been increasing interest in coalescent models which admit multiple mergers of ancestral lineages; and to model hybridization and coalescence simultaneously. Hybrid-Lambda is a software package that simulates gene genealogies under multiple merger and Kingman's coalescent processes within species networks or species trees. Hybrid-Lambda allows different coalescent processes to be specified for different populations, and allows for time to be converted between generations and coalescent units, by specifying a population size for each population. In addition, Hybrid-Lambda can generate simulated datasets, assuming the infinitely many sites mutation model, and compute the F ST statistic. As an illustration, we apply Hybrid-Lambda to infer the time of subdivision of certain marine invertebrates under different coalescent processes. Hybrid-Lambda makes it possible to investigate biogeographic concordance among high fecundity species exhibiting skewed offspring distribution.

  20. Hybridization may facilitate in situ survival of endemic species through periods of climate change

    Science.gov (United States)

    Becker, Matthias; Gruenheit, Nicole; Steel, Mike; Voelckel, Claudia; Deusch, Oliver; Heenan, Peter B.; McLenachan, Patricia A.; Kardailsky, Olga; Leigh, Jessica W.; Lockhart, Peter J.

    2013-12-01

    Predicting survival and extinction scenarios for climate change requires an understanding of the present day ecological characteristics of species and future available habitats, but also the adaptive potential of species to cope with environmental change. Hybridization is one mechanism that could facilitate this. Here we report statistical evidence that the transfer of genetic information through hybridization is a feature of species from the plant genus Pachycladon that survived the Last Glacial Maximum in geographically separated alpine refugia in New Zealand's South Island. We show that transferred glucosinolate hydrolysis genes also exhibit evidence of intra-locus recombination. Such gene exchange and recombination has the potential to alter the chemical defence in the offspring of hybridizing species. We use a mathematical model to show that when hybridization increases the adaptive potential of species, future biodiversity will be best protected by preserving closely related species that hybridize rather than by conserving distantly related species that are genetically isolated.

  1. Strongly asymmetric hybridization barriers shape the origin of a new polyploid species and its hybrid ancestor.

    Science.gov (United States)

    Vallejo-Marín, Mario; Cooley, Arielle M; Lee, Michelle Yuequi; Folmer, Madison; McKain, Michael R; Puzey, Joshua R

    2016-07-01

    Hybridization between diploids and tetraploids can lead to new allopolyploid species, often via a triploid intermediate. Viable triploids are often produced asymmetrically, with greater success observed for "maternal-excess" crosses where the mother has a higher ploidy than the father. Here we investigated the evolutionary origins of Mimulus peregrinus, an allohexaploid recently derived from the triploid M. ×robertsii, to determine whether reproductive asymmetry has shaped the formation of this new species. We used reciprocal crosses between the diploid (M. guttatus) and tetraploid (M. luteus) progenitors to determine the viability of triploid M. ×robertsii hybrids resulting from paternal- vs. maternal-excess crosses. To investigate whether experimental results predict patterns seen in the field, we performed parentage analyses comparing natural populations of M. peregrinus to its diploid, tetraploid, and triploid progenitors. Organellar sequences obtained from pre-existing genomic data, supplemented with additional genotyping was used to establish the maternal ancestry of multiple M. peregrinus and M. ×robertsii populations. We found strong evidence for asymmetric origins of M. peregrinus, but opposite to the common pattern, with paternal-excess crosses significantly more successful than maternal-excess crosses. These results successfully predicted hybrid formation in nature: 111 of 114 M. ×robertsii individuals, and 27 of 27 M. peregrinus, had an M. guttatus maternal haplotype. This study, which includes the first Mimulus chloroplast genome assembly, demonstrates the utility of parentage analysis through genome skimming. We highlight the benefits of complementing genomic analyses with experimental approaches to understand asymmetry in allopolyploid speciation. © 2016 Botanical Society of America.

  2. The repetitive component of the sunflower genome

    Directory of Open Access Journals (Sweden)

    T. Giordani

    2014-08-01

    Full Text Available The sunflower (Helianthus annuus and species belonging to the genus Helianthus are emerging as a model species and genus for a number of studies on genome evolution. In this review, we report on the repetitive component of the H. annuus genome at the biochemical, molecular, cytological, and genomic levels. Recent work on sunflower genome composition is described, with emphasis on different types of repeat sequences, especially LTR-retrotransposons, of which we report on isolation, characterisation, cytological localisation, transcription, dynamics of proliferation, and comparative analyses within the genus Helianthus.

  3. Sesquiterpene Lactone Composition of Wild and Cultivated Sunflowers and Biological Activity against an Insect Pest.

    Science.gov (United States)

    Prasifka, Jarrad R; Spring, Otmar; Conrad, Jürgen; Cook, Leonard W; Palmquist, Debra E; Foley, Michael E

    2015-04-29

    Sesquiterpene lactones in sunflowers, Helianthus spp., are important to interactions with pathogens, weeds, and insects. Across a broad range of Helianthus annuus, differences in composition of sesquiterpene lactones extracted from disc florets were found between wild and cultivated sunflowers and also between distinct groups of inbreds used to produce sunflower hybrids. Discriminant function analysis showed the presence and relative abundance of argophyllone B, niveusin B, and 15-hydroxy-3-dehydrodesoxyfruticin were usually (75%) effective at classifying wild sunflowers, cultivated inbreds, and hybrids. Argophyllone B reduced the larval mass of the sunflower moth, Homeosoma electellum, by >30%, but only at a dose greater than that found in florets. Low doses of mixed extracts from cultivated florets produced a similar (≈40%) reduction in larval mass, suggesting combinations of sesquiterpene lactones act additively. Although the results support a role for sesquiterpene lactones in herbivore defense of cultivated sunflowers, additional information is needed to use these compounds purposefully in breeding.

  4. Multifaceted, cross-generational costs of hybridization in sibling Drosophila species.

    Directory of Open Access Journals (Sweden)

    Erin M Myers

    Full Text Available Maladaptive hybridization, as determined by the pattern and intensity of selection against hybrid individuals, is an important factor contributing to the evolution of prezygotic reproductive isolation. To identify the consequences of hybridization between Drosophila pseudoobscura and D. persimilis, we estimated multiple fitness components for F1 hybrids and backcross progeny and used these to compare the relative fitness of parental species and their hybrids across two generations. We document many sources of intrinsic (developmental and extrinsic (ecological selection that dramatically increase the fitness costs of hybridization beyond the well-documented F1 male sterility in this model system. Our results indicate that the cost of hybridization accrues over multiple generations and reinforcement in this system is driven by selection against hybridization above and beyond the cost of hybrid male sterility; we estimate a fitness loss of >95% relative to the parental species across two generations of hybridization. Our findings demonstrate the importance of estimating hybridization costs using multiple fitness measures from multiple generations in an ecologically relevant context; so doing can reveal intense postzygotic selection against hybridization and thus, an enhanced role for reinforcement in the evolution of populations and diversification of species.

  5. Plant Regeneration and Somatic Embryogenesis from Immature Embryos Derived through Interspecific Hybridization among Different Carica Species

    OpenAIRE

    Azad, Md. Abul; Rabbani, Md. Golam; Amin, Latifah

    2012-01-01

    Plant regeneration and somatic embryogenesis through interspecific hybridization among different Carica species were studied for the development of a papaya ringspot virus-resistant variety. The maximum fruit sets were recorded from the cross of the native variety C. papaya cv. Shahi with the wild species C. cauliflora. The highest hybrid embryos were recorded at 90 days after pollination and the embryos were aborted at 150 days after pollination. The immature hybrid embryos were used for pla...

  6. The sunflower downy mildew pathogen Plasmopara halstedii.

    Science.gov (United States)

    Gascuel, Quentin; Martinez, Yves; Boniface, Marie-Claude; Vear, Felicity; Pichon, Magalie; Godiard, Laurence

    2015-02-01

    Downy mildew of sunflower is caused by Plasmopara halstedii (Farlow) Berlese & de Toni. Plasmopara halstedii is an obligate biotrophic oomycete pathogen that attacks annual Helianthus species and cultivated sunflower, Helianthus annuus. Depending on the sunflower developmental stage at which infection occurs, the characteristic symptoms range from young seedling death, plant dwarfing, leaf bleaching and sporulation to the production of infertile flowers. Downy mildew attacks can have a great economic impact on sunflower crops, and several Pl resistance genes are present in cultivars to protect them against the disease. Nevertheless, some of these resistances have been overcome by the occurrence of novel isolates of the pathogen showing increased virulence. A better characterization of P. halstedii infection and dissemination mechanisms, and the identification of the molecular basis of the interaction with sunflower, is a prerequisite to efficiently fight this pathogen. This review summarizes what is currently known about P. halstedii, provides new insights into its infection cycle on resistant and susceptible sunflower lines using scanning electron and light microscopy imaging, and sheds light on the pathogenicity factors of P. halstedii obtained from recent molecular data. Kingdom Stramenopila; Phylum Oomycota; Class Oomycetes; Order Peronosporales; Family Peronosporaceae; Genus Plasmopara; Species Plasmopara halstedii. Sunflower seedling damping off, dwarfing of the plant, bleaching of leaves, starting from veins, and visible white sporulation, initially on the lower side of cotyledons and leaves. Plasmopara halstedii infection may severely impact sunflower seed yield. In spring, germination of overwintered sexual oospores leads to sunflower root infection. Intercellular hyphae are responsible for systemic plant colonization and the induction of disease symptoms. Under humid and fresh conditions, dissemination structures are produced by the pathogen on all

  7. Density Distribution Sunflower Plots

    Directory of Open Access Journals (Sweden)

    William D. Dupont

    2003-01-01

    Full Text Available Density distribution sunflower plots are used to display high-density bivariate data. They are useful for data where a conventional scatter plot is difficult to read due to overstriking of the plot symbol. The x-y plane is subdivided into a lattice of regular hexagonal bins of width w specified by the user. The user also specifies the values of l, d, and k that affect the plot as follows. Individual observations are plotted when there are less than l observations per bin as in a conventional scatter plot. Each bin with from l to d observations contains a light sunflower. Other bins contain a dark sunflower. In a light sunflower each petal represents one observation. In a dark sunflower, each petal represents k observations. (A dark sunflower with p petals represents between /2-pk k and /2+pk k observations. The user can control the sizes and colors of the sunflowers. By selecting appropriate colors and sizes for the light and dark sunflowers, plots can be obtained that give both the overall sense of the data density distribution as well as the number of data points in any given region. The use of this graphic is illustrated with data from the Framingham Heart Study. A documented Stata program, called sunflower, is available to draw these graphs. It can be downloaded from the Statistical Software Components archive at http://ideas.repec.org/c/boc/bocode/s430201.html . (Journal of Statistical Software 2003; 8 (3: 1-5. Posted at http://www.jstatsoft.org/index.php?vol=8 .

  8. The cultivated sunflower - a source of renewable resources for the future. Die Sonnenblume - eine 'nachwachsende Rohstoffquelle' mit Zukunft

    Energy Technology Data Exchange (ETDEWEB)

    Friedt, W. (Giessen Univ. (Germany). Inst. fuer Pflanzenbau und Pflanzenzuechtung 1)

    1992-02-01

    Our institute has been dealing with breeding of oil crops for more than four decades, now. In this context, the cultivated sunflower (Helianthus annuus) in one of our favorite subjects. This plant has long been considered as a species very recalcitrant to various methods of biotechnology. However, substantial progress has been made in recent years, e.g. with regard to the characterization and description of wild Helianthus species, including their biochemical and molecular genetics, and optimization of tissue and embryo culture techniques for rapid propagation and screening for stress tolerance or disease resistance in vitro, an establishment of methods for the reproducible regeneration of androgenetic haploids for an accelerated development of doubled haploids, i.e. inbred lines, the development of improved techniques of chromosome doubling as a prerequisite for an application of doubled haploids and interspecific hybrids in a sunflower breeding programme, the development of applicable techniques for a successful and stable genetic transformation of sunflower. Nowadays, these techniques can be considered highly valuable complements for classical breeding methods in order to provide valuable basic material. In particular, new sunflower lines and hybrids with modified oil quality, i.e. fatty acid composition, have been developed recently. Such types of novel seed oil are highly appreciated by our chemical industry, e.g. for the production of new oleochemicals. (orig.).

  9. Outcomes of extensive hybridization and introgression in Epidendrum (Orchidaceae): can we rely on species boundaries?

    Science.gov (United States)

    Vega, Yesenia; Marques, Isabel; Castro, Sílvia; Loureiro, João

    2013-01-01

    Hybridization has the potential to contribute to phenotypic and genetic variation and can be a major evolutionary mechanism. However, when hybridization is extensive it can also lead to the blurring of species boundaries and the emergence of cryptic species (i.e., two or more species not distinguishable morphologically). In this study, we address this hypothesis in Epidendrum, the largest Neotropical genus of orchids where hybridization is apparently so common that it may explain the high levels of morphological diversity found. Nonetheless, this hypothesis is mostly based on the intermediacy of morphological characters and intermediacy by itself is not a proof of hybridization. Therefore, in this study, we first assessed the existence of hybrids using cpDNA and AFLP data gathered from a large-scale sampling comprising 1038 plants of three species of Epidendrum (E. calanthum, E. cochlidium and E. schistochilum). Subsequently, a Bayesian assignment of individuals into different genetic classes (pure species, F1, F2 or backcross generations) revealed that hybrid genotypes were prevalent in all sympatric populations. In most cases, parental species were not assigned as pure individuals, rather consisting in backcrossed genotypes or F1 hybrids. We also found that reproductive barriers are apparently very weak in Epidendrum because the three species largely overlapped in their flowering periods and interspecific crosses always produced viable seeds. Further, hybridization contributed to enhance floral variability, genome size and reproductive success since we found that these traits were always higher in hybrid classes (F1, F2 and backcrosses) than in pure parental species, and offer an explanation for the blurring of species boundaries in this genus of orchids. We hypothesize that these natural hybrids possess an evolutionary advantage, which may explain the high rates of cryptic species observed in this genus.

  10. Outcomes of extensive hybridization and introgression in Epidendrum (Orchidaceae: can we rely on species boundaries?

    Directory of Open Access Journals (Sweden)

    Yesenia Vega

    Full Text Available Hybridization has the potential to contribute to phenotypic and genetic variation and can be a major evolutionary mechanism. However, when hybridization is extensive it can also lead to the blurring of species boundaries and the emergence of cryptic species (i.e., two or more species not distinguishable morphologically. In this study, we address this hypothesis in Epidendrum, the largest Neotropical genus of orchids where hybridization is apparently so common that it may explain the high levels of morphological diversity found. Nonetheless, this hypothesis is mostly based on the intermediacy of morphological characters and intermediacy by itself is not a proof of hybridization. Therefore, in this study, we first assessed the existence of hybrids using cpDNA and AFLP data gathered from a large-scale sampling comprising 1038 plants of three species of Epidendrum (E. calanthum, E. cochlidium and E. schistochilum. Subsequently, a Bayesian assignment of individuals into different genetic classes (pure species, F1, F2 or backcross generations revealed that hybrid genotypes were prevalent in all sympatric populations. In most cases, parental species were not assigned as pure individuals, rather consisting in backcrossed genotypes or F1 hybrids. We also found that reproductive barriers are apparently very weak in Epidendrum because the three species largely overlapped in their flowering periods and interspecific crosses always produced viable seeds. Further, hybridization contributed to enhance floral variability, genome size and reproductive success since we found that these traits were always higher in hybrid classes (F1, F2 and backcrosses than in pure parental species, and offer an explanation for the blurring of species boundaries in this genus of orchids. We hypothesize that these natural hybrids possess an evolutionary advantage, which may explain the high rates of cryptic species observed in this genus.

  11. Naturally occurring hybrids of coral reef butterflyfishes have similar fitness compared to parental species.

    Science.gov (United States)

    Montanari, Stefano R; Hobbs, Jean-Paul A; Pratchett, Morgan S; Bay, Line K; van Herwerden, Lynne

    2017-01-01

    Hybridisation can produce evolutionary novelty by increasing fitness and adaptive capacity. Heterosis, or hybrid vigour, has been documented in many plant and animal taxa, and is a notable consequence of hybridisation that has been exploited for decades in agriculture and aquaculture. On the contrary, loss of fitness in naturally occurring hybrid taxa has been observed in many cases. This can have negative consequences for the parental species involved (wasted reproductive effort), and has raised concerns for species conservation. This study evaluates the relative fitness of previously documented butterflyfish hybrids of the genus Chaetodon from the Indo-Pacific suture zone at Christmas Island. Histological examination confirmed the reproductive viability of Chaetodon hybrids. Examination of liver lipid content showed that hybrid body condition was not significantly different from parent species body condition. Lastly, size at age data revealed no difference in growth rates and asymptotic length between hybrids and parent species. Based on the traits measured in this study, naturally occurring hybrids of Chaetodon butterflyfishes have similar fitness to their parental species, and are unlikely to supplant parental species under current environmental conditions at the suture zone. However, given sufficient fitness and ongoing genetic exchange between the respective parental species, hybrids are likely to persist within the suture zone.

  12. Naturally occurring hybrids of coral reef butterflyfishes have similar fitness compared to parental species.

    Directory of Open Access Journals (Sweden)

    Stefano R Montanari

    Full Text Available Hybridisation can produce evolutionary novelty by increasing fitness and adaptive capacity. Heterosis, or hybrid vigour, has been documented in many plant and animal taxa, and is a notable consequence of hybridisation that has been exploited for decades in agriculture and aquaculture. On the contrary, loss of fitness in naturally occurring hybrid taxa has been observed in many cases. This can have negative consequences for the parental species involved (wasted reproductive effort, and has raised concerns for species conservation. This study evaluates the relative fitness of previously documented butterflyfish hybrids of the genus Chaetodon from the Indo-Pacific suture zone at Christmas Island. Histological examination confirmed the reproductive viability of Chaetodon hybrids. Examination of liver lipid content showed that hybrid body condition was not significantly different from parent species body condition. Lastly, size at age data revealed no difference in growth rates and asymptotic length between hybrids and parent species. Based on the traits measured in this study, naturally occurring hybrids of Chaetodon butterflyfishes have similar fitness to their parental species, and are unlikely to supplant parental species under current environmental conditions at the suture zone. However, given sufficient fitness and ongoing genetic exchange between the respective parental species, hybrids are likely to persist within the suture zone.

  13. Natural hybridization in heliconiine butterflies: the species boundary as a continuum

    Directory of Open Access Journals (Sweden)

    Beltrán Margarita

    2007-02-01

    Full Text Available Abstract Background To understand speciation and the maintenance of taxa as separate entities, we need information about natural hybridization and gene flow among species. Results Interspecific hybrids occur regularly in Heliconius and Eueides (Lepidoptera: Nymphalidae in the wild: 26–29% of the species of Heliconiina are involved, depending on species concept employed. Hybridization is, however, rare on a per-individual basis. For one well-studied case of species hybridizing in parapatric contact (Heliconius erato and H. himera, phenotypically detectable hybrids form around 10% of the population, but for species in sympatry hybrids usually form less than 0.05% of individuals. There is a roughly exponential decline with genetic distance in the numbers of natural hybrids in collections, both between and within species, suggesting a simple "exponential failure law" of compatibility as found in some prokaryotes. Conclusion Hybridization between species of Heliconius appears to be a natural phenomenon; there is no evidence that it has been enhanced by recent human habitat disturbance. In some well-studied cases, backcrossing occurs in the field and fertile backcrosses have been verified in insectaries, which indicates that introgression is likely, and recent molecular work shows that alleles at some but not all loci are exchanged between pairs of sympatric, hybridizing species. Molecular clock dating suggests that gene exchange may continue for more than 3 million years after speciation. In addition, one species, H. heurippa, appears to have formed as a result of hybrid speciation. Introgression may often contribute to adaptive evolution as well as sometimes to speciation itself, via hybrid speciation. Geographic races and species that coexist in sympatry therefore form part of a continuum in terms of hybridization rates or probability of gene flow. This finding concurs with the view that processes leading to speciation are continuous, rather than

  14. Reconstructing the History of Selection during Homoploid Hybrid Speciation

    Science.gov (United States)

    Karrenberg, Sophie; Lexer, Christian; Rieseberg, Loren H.

    2008-01-01

    This study aims to identify selection pressures during the historical process of homoploid hybrid speciation in three Helianthus (sunflower) hybrid species. If selection against intrinsic genetic incompatibilities (fertility selection) or for important morphological/ecological traits (phenotypic selection) were important in hybrid speciation, we would expect this selection to have influenced the parentage of molecular markers or chromosomal segments in the hybrid species’ genomes. To infer past selection, we compared the parentage of molecular markers in high-density maps of the three hybrid species with predicted marker parentage from an analysis of fertility selection in artificial hybrids and from the directions of quantitative trait loci effects with respect to the phenotypes of the hybrid species. Multiple logistic regression models were consistent with both fertility and phenotypic selection in all three species. To further investigate traits under selection, we used a permutation test to determine whether marker parentage predicted from groups of functionally related traits differed from neutral expectations. Our results suggest that trait groups associated with ecological divergence were under selection during hybrid speciation. This study presents a new method to test for selection and supports earlier claims that fertility selection and phenotypic selection on ecologically relevant traits have operated simultaneously during sunflower hybrid speciation. PMID:17479459

  15. Heterosis profile of sunflower leaves: a label free proteomics approach.

    Science.gov (United States)

    Mohayeji, Mehdi; Capriotti, Anna Laura; Cavaliere, Chiara; Piovesana, Susy; Samperi, Roberto; Stampachiacchiere, Serena; Toorchi, Mahmood; Lagana, Aldo

    2014-03-17

    Heterosis is the superior performance of heterozygous F1-hybrid plants compared with their homozygous genetically distinct parents. The proteome of leaves of one sunflower hybrid and its parental inbred lines was analyzed by label free LC-MS/MS. A total of 1998 proteins were identified. Among them 38 proteins indicated heterosis pattern in hybrid compared with midparents. The results showed an increment of photosynthesis capacity, assimilation rate, nitrogen fixation, cell growth and reducing in some energy-consuming processes like protein production, response to stresses and respiration. These results suggest that heterosis mechanisms increase input energy of plant with reinforcement of carbon fixation pathway and reduction in consumed energy toward production of superior hybrid. This study could help to better elucidate what mechanisms are involved in heterosis of sunflower leaves and what happens at proteome level. The current work describes the first study in which gel-free shotgun proteomics was used to compare the proteome of leaves of one sunflower hybrid to its parental inbred lines. In this study 1998 proteins were identified from sunflower leaves with label free nano LC-MS/MS. The numbers of 38 proteins significantly showed heterosis pattern. The comparison between hybrid and parental inbred lines showed that hybrid vigor is actually linked by emphasizing the assimilation rate and low energy consumption. Copyright © 2014 Elsevier B.V. All rights reserved.

  16. Silky Sunflowers & Swirly Skies

    Science.gov (United States)

    Welling, Linda

    2012-01-01

    In this article, second-graders create a sunflower drawing using pastel techniques that produce similar effects to Vincent van Gogh's brushstrokes. They also learn how layering colors and using white to lighten colors creates depth in their flowers.

  17. A Homoploid Hybrid Between Wild Vigna Species Found in a Limestone Karst

    Science.gov (United States)

    Takahashi, Yu; Iseki, Kohtaro; Kitazawa, Kumiko; Muto, Chiaki; Somta, Prakit; Irie, Kenji; Naito, Ken; Tomooka, Norihiko

    2015-01-01

    Genus Vigna comprise several domesticated species including cowpea and mungbean, and diverse wild species. We found an introgressive hybrid population derived from two wild species, Vigna umbellata and Vigna exilis, in Ratchaburi district, Thailand. The hybrid was morphologically similar to V. umbellata but habituated in a limestone rock mountain, which is usually dominated by V. exilis. Analyzing simple sequence repeat loci indicated the hybrid has undergone at least one round of backcross by V. umbellata. We found the hybrid acquired vigorous growth from V. umbellata and drought tolerance plus early flowering from V. exilis, and thus has taken over some habitats of V. exilis in limestone karsts. Given the wide crossability of V. umbellata, the hybrid can be a valuable genetic resource to improve drought tolerance of some domesticated species. PMID:26648953

  18. Widespread hybridization among species of Indian major carps in hatcheries, but not in the wild

    DEFF Research Database (Denmark)

    Simonsen, V.; Hansen, Michael Møller; Mensberg, Karen-Lise Dons

    2005-01-01

    Twenty-one allozyme loci in samples of wild-caught and hatchery-reared Indian major carps from Bangladesh were analysed. Bayesian model-based clustering analysis revealed the presence of four taxa, corresponding to the three known species along with a fourth unknown taxon present in two hatchery...... samples. Individual admixture coefficients showed that 24% of all hatchery-reared fishes were hybrids, whereas a single hybrid was observed in the wild-caught samples. Only catla Catla catla x rohu Labeo rohita and mrigal Cirrhinus cirrhosus x rohu hybrids were observed, the vast majority of which were F......-hybrids in hatchery samples, reproductive barriers among species have so far precluded widespread introgression. Continued hybridization may eventually lead to a breakdown of species barriers, thereby compromising the genetic integrity of the species in the wild, and leading to production losses...

  19. Antibacterial activity of ozonized sunflower oil (Oleozon).

    Science.gov (United States)

    Sechi, L A; Lezcano, I; Nunez, N; Espim, M; Duprè, I; Pinna, A; Molicotti, P; Fadda, G; Zanetti, S

    2001-02-01

    To evaluate the antimicrobial effect of the ozonized sunflower oil (Oleozon) on different bacterial species isolated from different sites. The effect of Oleozon on Mycobacteria, staphylococci, streptococci, enterococci, Pseudomonas and Escherichia coli was tested. The sunflower oil was ozonized at the Centro de Investigaciones del Ozone (CENIC, Havana, Cuba) by an ozone generator. MICs were determined by the agar dilution method. For Mycobacteria, the MIC of Oleozon was determined on solid medium by a microdrop agar proportion test. Oleozon showed antimicrobial activity against all strains analysed, with an MIC ranging from 1.18 to 9.5 mg ml-1. Oleozon showed a valuable antimicrobial activity against all micro-organisms tested. Results suggest that Mycobacteria are more susceptible to Oleozon than the other bacteria tested. The wide availability of sunflower oil makes Oleozon a competitive antimicrobial agent. These results should prompt the setting up of some clinical trials to compare Oleozon with other antimicrobial agents.

  20. Hybridization among Three Native North American Canis Species in a Region of Natural Sympatry

    OpenAIRE

    Hailer, Frank; Leonard, Jennifer A.

    2008-01-01

    BACKGROUND: Population densities of many species throughout the world are changing due to direct persecution as well as anthropogenic habitat modification. These changes may induce or increase the frequency of hybridization among taxa. If extensive, hybridization can threaten the genetic integrity or survival of endangered species. Three native species of the genus Canis, coyote (C. latrans), Mexican wolf (C. lupus baileyi) and red wolf (C. rufus), were historically sympatric in Texas, United...

  1. Genome skimming reveals the origin of the Jerusalem Artichoke tuber crop species: neither from Jerusalem nor an artichoke.

    Science.gov (United States)

    Bock, Dan G; Kane, Nolan C; Ebert, Daniel P; Rieseberg, Loren H

    2014-02-01

    The perennial sunflower Helianthus tuberosus, known as Jerusalem Artichoke or Sunchoke, was cultivated in eastern North America before European contact. As such, it represents one of the few taxa that can support an independent origin of domestication in this region. Its tubers were adopted as a source of food and forage when the species was transferred to the Old World in the early 1600s, and are still used today. Despite the cultural and economic importance of this tuber crop species, its origin is debated. Competing hypotheses implicate the occurrence of polyploidization with or without hybridization, and list the annual sunflower H. annuus and five distantly related perennial sunflower species as potential parents. Here, we test these scenarios by skimming the genomes of diverse populations of Jerusalem Artichoke and its putative progenitors. We identify relationships among Helianthus taxa using complete plastomes (151 551 bp), partial mitochondrial genomes (196 853 bp) and 35S (8196 bp) and 5S (514 bp) ribosomal DNA. Our results refute the possibility that Jerusalem Artichoke is of H. annuus ancestry. We provide the first genetic evidence that this species originated recursively from perennial sunflowers of central-eastern North America via hybridization between tetraploid Hairy Sunflower and diploid Sawtooth Sunflower. © 2013 The Authors. New Phytologist © 2013 New Phytologist Trust.

  2. Hybridization and genome evolution II: Mechanisms of species divergence and their effects on evolution in hybrids

    Directory of Open Access Journals (Sweden)

    Richard I. BAILEY, Fabrice EROUKHMANOFF, Glenn-Peter SæTRE

    2013-10-01

    Full Text Available Recent genomic studies have highlighted the importance of hybridization and gene exchange in evolution. We ask what factors cause variation in the impact of hybridization, through adaptation in hybrids and the likelihood of hybrid speciation. During speciation, traits that diverge due to both divergent and stabilizing selection can contribute to the buildup of reproductive isolation. Divergent directional selection in parent taxa should lead to intermediate phenotypes in hybrids, whereas stabilizing selection can also produce extreme, transgressive phenotypes when hybridization occurs. By examining existing theory and empirical data, we discuss how these effects, combined with differences between modes of divergence in the chromosomal distribution of incompatibilities, affect adaptation and speciation in hybrid populations. The result is a clear and testable set of predictions that can be used to examine hybrid adaptation and speciation. Stabilizing selection in parents increases transgression in hybrids, increasing the possibility for novel adaptation. Divergent directional selection causes intermediate hybrid phenotypes and increases their ability to evolve along the direction of parental differentiation. Stabilizing selection biases incompatibilities towards autosomes, leading to reduced sexual correlations in trait values and reduced pleiotropy in hybrids, and hence increased freedom in the direction of evolution. Directional selection causes a bias towards sex-linked incompatibilities, with the opposite consequences. Divergence by directional selection leads to greater dominance effects than stabilizing selection, with major but variable impacts on hybrid evolution [Current Zoology 59 (5: 675-685, 2013].

  3. Isolation of three diterpenoid acids from sunflowers, as oviposition stimulants for the banded sunflower moth, Cochylis hospes.

    Science.gov (United States)

    Morris, Bruce D; Charlet, Laurence D; Foster, Stephen P

    2009-01-01

    The banded sunflower moth (BSFM), Cochylis hospes Walshingham (Lepidoptera: Cochylidae) is a specialist insect, the larvae of which feed on sunflowers, Helianthus spp., and a few other species of Compositae. It is one of the most important pests of sunflower in the USA. Previous work on H. annuus, the cultivated sunflower, revealed two diterpenoids that function as oviposition stimulants for female BSFM, and that other, more polar compounds also stimulated oviposition. Using a bioassay-guided approach, we isolated three additional diterpenoids, grandifloric acid (1), 15beta-hydroxy-ent-trachyloban-19-oic acid (2), and 17-hydroxy-16alpha-ent-kauran-19-oic acid (3), from polar fractions of pre-bloom sunflower head extracts. In laboratory bioassays, purified natural samples of each of these compounds stimulated oviposition by female BSFM. Structure-activity relationships of the five diterpenoids known to stimulate oviposition by female BSFM are discussed.

  4. Does genetic distance between parental species influence outcomes of hybridization among coral reef butterflyfishes?

    Science.gov (United States)

    Montanari, Stefano R; Hobbs, Jean-Paul A; Pratchett, Morgan S; Bay, Line K; Van Herwerden, Lynne

    2014-06-01

    Christmas Island is located at the overlap of the Indian and Pacific Ocean marine provinces and is a hot spot for marine hybridization. Here, we evaluate the ecological framework and genetic consequences of hybridization between butterflyfishes Chaetodon guttatissimus and Chaetodon punctatofasciatus. Further, we compare our current findings to those from a previous study of hybridization between Chaetodon trifasciatus and Chaetodon lunulatus. For both species groups, habitat and dietary overlap between parental species facilitate frequent heterospecific encounters. Low abundance of potential mates promotes heterospecific pair formation and the breakdown of assortative mating. Despite similarities in ecological frameworks, the population genetic signatures of hybridization differ between the species groups. Mitochondrial and nuclear data from C. guttatissimus × C. punctatofasciatus (1% divergence at cyt b) show bidirectional maternal contributions and relatively high levels of introgression, both inside and outside the Christmas Island hybrid zone. In contrast, C. trifasciatus × C. lunulatus (5% cyt b divergence) exhibit unidirectional mitochondrial inheritance and almost no introgression. Back-crossing of hybrid C. guttatissimus × C. punctatofasciatus and parental genotypes may eventually confound species-specific signals within the hybrid zone. In contrast, hybrids of C. trifasciatus and C. lunulatus may coexist with and remain genetically distinct from the parents. Our results, and comparisons with hybridization studies in other reef fish families, indicate that genetic distance between hybridizing species may be a factor influencing outcomes of hybridization in reef fish, which is consistent with predictions from terrestrially derived hybridization theory. © 2014 John Wiley & Sons Ltd.

  5. Hybridization of several Aerides species and in vitro germination of ...

    African Journals Online (AJOL)

    Administrator

    2011-09-14

    Sep 14, 2011 ... Continuing loss of native orchids has lead to an increased emphasis on orchid conservation. The loss of diversity in orchid population is worrying and conser- vation method including hybridization and in-vitro propagation are essential. Hybridization of orchids intro- duces a new dimension in the floriculture ...

  6. Combination of Multiple Resistance Traits from Wild Relative Species in Chrysanthemum via Trigeneric Hybridization

    Science.gov (United States)

    Deng, Yanming; Jiang, Jiafu; Chen, Sumei; Teng, Nianjun; Song, Aiping; Guan, Zhiyong; Fang, Weimin; Chen, Fadi

    2012-01-01

    Background With the objective of combining multiple resistant traits from wild relative species in florist’s chrysanthemums, trigeneric hybridization was conducted by crossing two intergeneric F1 hybrids Chrysanthemum grandiflorum × Artemisia vulgaris and Chrysanthemum crassum × Crossostephium chinense. Methodology/Principal Findings To assess post-pollination phenomena, we investigated pollen germination on the stigma and embryo development, using fluorescence and scanning electron microscopy and paraffin-embedded sections, respectively. We selected eight putative trigeneric hybrid lines that showed the greatest morphological differences from the parents from among the progeny derived via embryo rescue. The hybridity of one trigeneric hybrid was further confirmed by fluorescent genomic in situ hybridization; in addition, the aphid resistance and salt tolerance of this hybrid were higher than those of the chrysanthemum parent and the C. grandiflorum × A. vulgaris F1 hybrid, respectively. Conclusions/Significance The enhanced aphid resistance of the hybrid line reflects the inheritance of chromosomes from A. vulgaris, which carries genes that encode bioactive components. The enhanced salt tolerance of the trigeneric hybrid is attributable to inheritance of genetic materials from Chrysanthemum crassum and Crossostephium chinense, which act to maintain the compartmentation of Na+ and K+ ions and their selective transportation among different organs to avert deleterious effects and protect the photosynthetic apparatus. The results indicate that trigeneric hybridization between different bigeneric hybrids is a promising method for combination of multiple stress-resistance traits for improvement of chrysanthemum. PMID:22952958

  7. Combination of multiple resistance traits from wild relative species in Chrysanthemum via trigeneric hybridization.

    Science.gov (United States)

    Deng, Yanming; Jiang, Jiafu; Chen, Sumei; Teng, Nianjun; Song, Aiping; Guan, Zhiyong; Fang, Weimin; Chen, Fadi

    2012-01-01

    With the objective of combining multiple resistant traits from wild relative species in florist's chrysanthemums, trigeneric hybridization was conducted by crossing two intergeneric F(1) hybrids Chrysanthemum grandiflorum × Artemisia vulgaris and Chrysanthemum crassum × Crossostephium chinense. To assess post-pollination phenomena, we investigated pollen germination on the stigma and embryo development, using fluorescence and scanning electron microscopy and paraffin-embedded sections, respectively. We selected eight putative trigeneric hybrid lines that showed the greatest morphological differences from the parents from among the progeny derived via embryo rescue. The hybridity of one trigeneric hybrid was further confirmed by fluorescent genomic in situ hybridization; in addition, the aphid resistance and salt tolerance of this hybrid were higher than those of the chrysanthemum parent and the C. grandiflorum × A. vulgaris F(1) hybrid, respectively. The enhanced aphid resistance of the hybrid line reflects the inheritance of chromosomes from A. vulgaris, which carries genes that encode bioactive components. The enhanced salt tolerance of the trigeneric hybrid is attributable to inheritance of genetic materials from Chrysanthemum crassum and Crossostephium chinense, which act to maintain the compartmentation of Na(+) and K(+) ions and their selective transportation among different organs to avert deleterious effects and protect the photosynthetic apparatus. The results indicate that trigeneric hybridization between different bigeneric hybrids is a promising method for combination of multiple stress-resistance traits for improvement of chrysanthemum.

  8. Hybridization between two cestode species and its consequences for intermediate host range

    Directory of Open Access Journals (Sweden)

    Henrich Tina

    2013-02-01

    Full Text Available Abstract Background Many parasites show an extraordinary degree of host specificity, even though a narrow range of host species reduces the likelihood of successful transmission. In this study, we evaluate the genetic basis of host specificity and transmission success of experimental F1 hybrids from two closely related tapeworm species (Schistocephalus solidus and S. pungitii, both highly specific to their respective vertebrate second intermediate hosts (three- and nine-spined sticklebacks, respectively. Methods We used an in vitro breeding system to hybridize Schistocephalus solidus and S. pungitii; hybridization rate was quantified using microsatellite markers. We measured several fitness relevant traits in pure lines of the parental parasite species as well as in their hybrids: hatching rates, infection rates in the copepod first host, and infection rates and growth in the two species of stickleback second hosts. Results We show that the parasites can hybridize in the in vitro system, although the proportion of self-fertilized offspring was higher in the heterospecific breeding pairs than in the control pure parental species. Hybrids have a lower hatching rate, but do not show any disadvantages in infection of copepods. In fish, hybrids were able to infect both stickleback species with equal frequency, whereas the pure lines were only able to infect their normal host species. Conclusions Although not yet documented in nature, our study shows that hybridization in Schistocephalus spp. is in principle possible and that, in respect to their expanded host range, the hybrids are fitter. Further studies are needed to find the reason for the maintenance of the species boundaries in wild populations.

  9. Hybridization between two cestode species and its consequences for intermediate host range.

    Science.gov (United States)

    Henrich, Tina; Benesh, Daniel P; Kalbe, Martin

    2013-02-07

    Many parasites show an extraordinary degree of host specificity, even though a narrow range of host species reduces the likelihood of successful transmission. In this study, we evaluate the genetic basis of host specificity and transmission success of experimental F(1) hybrids from two closely related tapeworm species (Schistocephalus solidus and S. pungitii), both highly specific to their respective vertebrate second intermediate hosts (three- and nine-spined sticklebacks, respectively). We used an in vitro breeding system to hybridize Schistocephalus solidus and S. pungitii; hybridization rate was quantified using microsatellite markers. We measured several fitness relevant traits in pure lines of the parental parasite species as well as in their hybrids: hatching rates, infection rates in the copepod first host, and infection rates and growth in the two species of stickleback second hosts. We show that the parasites can hybridize in the in vitro system, although the proportion of self-fertilized offspring was higher in the heterospecific breeding pairs than in the control pure parental species. Hybrids have a lower hatching rate, but do not show any disadvantages in infection of copepods. In fish, hybrids were able to infect both stickleback species with equal frequency, whereas the pure lines were only able to infect their normal host species. Although not yet documented in nature, our study shows that hybridization in Schistocephalus spp. is in principle possible and that, in respect to their expanded host range, the hybrids are fitter. Further studies are needed to find the reason for the maintenance of the species boundaries in wild populations.

  10. Triploid Production from Interspecific Crosses of Two Diploid Perennial Helianthus with Diploid Cultivated Sunflower (Helianthus annuus L.).

    Science.gov (United States)

    Liu, Zhao; Seiler, Gerald J; Gulya, Thomas J; Feng, Jiuhuan; Rashid, Khalid Y; Cai, Xiwen; Jan, Chao-Chien

    2017-04-03

    Wild Helianthus species are a valuable genetic resource for the improvement of cultivated sunflower. We report the discovery and characterization of a unique high frequency production of triploids when cultivated sunflower was pollinated by specific accessions of diploid Helianthus nuttallii T. & G. and H. maximiliani Schr. Genomic in situ hybridization (GISH) analyses indicated that the triploid F1s had two genomes from the wild pollen sources and one from the cultivated line. Mitotic chromosome analyses indicated that the frequency of triploid progenies from the crosses of cultivated lines × H. nuttallii accession 102 (N102) was significantly higher than those of unexpected polyploid progenies from the crosses of wild perennial species × N102, and no unexpected polyploids were obtained from the reverse crosses. Pollen stainability analysis suggested the existence of a low percentage of unreduced (2n) male gametes in some accessions, especially N102 and H. maximiliani accession 1113 (M1113), which were generated at the telophase II and tetrad stages of meiosis. The triploid F1s could be the results of preferred fertilization of the low frequency of 2n male gametes with the female gametes of the cultivated sunflower, due to the dosage factors related to recognition and rejection of foreign pollen during fertilization. The triploids have been used to produce amphiploids and aneuploids. Future studies of the male gametes' fate from pollination through fertilization will further uncover the mechanism of this whole genome transmission. Studies of the genetic control of this trait will facilitate research on sunflower polyploidy speciation and evolution, and the utilization of this trait in sunflower breeding. Copyright © 2017 Liu et al.

  11. First artificial hybrid of the eel species Anguilla australis and Anguilla anguilla

    NARCIS (Netherlands)

    Burgerhout, E.; Brittijn, S.A.; Kurwie, T.; Decker, P.; Dirks, R.; Palstra, A.P.; Spaink, H.P.; Thillart, G.E.E.J.M.

    2011-01-01

    Background: Studies on artificial hybridization of different Anguilla species were conducted recently, i.e. female A. australis with male A. dieffenbachii, and female A. japonica with male A. anguilla. The existence of these artificial hybrids was however not demonstrated by independent genetic

  12. Selection against recombinant hybrids maintains reproductive isolation in hybridizing Populus species despite F1 fertility and recurrent gene flow.

    Science.gov (United States)

    Christe, Camille; Stölting, Kai N; Bresadola, Luisa; Fussi, Barbara; Heinze, Berthold; Wegmann, Daniel; Lexer, Christian

    2016-06-01

    Natural hybrid zones have proven to be precious tools for understanding the origin and maintenance of reproductive isolation (RI) and therefore species. Most available genomic studies of hybrid zones using whole- or partial-genome resequencing approaches have focused on comparisons of the parental source populations involved in genome admixture, rather than exploring fine-scale patterns of chromosomal ancestry across the full admixture gradient present between hybridizing species. We have studied three well-known European 'replicate' hybrid zones of Populus alba and P. tremula, two widespread, ecologically divergent forest trees, using up to 432 505 single-nucleotide polymorphisms (SNPs) from restriction site-associated DNA (RAD) sequencing. Estimates of fine-scale chromosomal ancestry, genomic divergence and differentiation across all 19 poplar chromosomes revealed strikingly contrasting results, including an unexpected preponderance of F1 hybrids in the centre of genomic clines on the one hand, and genomically localized, spatially variable shared variants consistent with ancient introgression between the parental species on the other. Genetic ancestry had a significant effect on survivorship of hybrid seedlings in a common garden trial, pointing to selection against early-generation recombinants. Our results indicate a role for selection against recombinant genotypes in maintaining RI in the face of apparent F1 fertility, consistent with the intragenomic 'coadaptation' model of barriers to introgression upon secondary contact. Whole-genome resequencing of hybridizing populations will clarify the roles of specific genetic pathways in RI between these model forest trees and may reveal which loci are affected most strongly by its cyclic breakdown. © 2016 John Wiley & Sons Ltd.

  13. Natural and Anthropogenic Hybridization in Two Species of Eastern Brazilian Marmosets (Callithrix jacchus and C. penicillata).

    Science.gov (United States)

    Malukiewicz, Joanna; Boere, Vanner; Fuzessy, Lisieux F; Grativol, Adriana D; de Oliveira E Silva, Ita; Pereira, Luiz C M; Ruiz-Miranda, Carlos R; Valença, Yuri M; Stone, Anne C

    2015-01-01

    Animal hybridization is well documented, but evolutionary outcomes and conservation priorities often differ for natural and anthropogenic hybrids. Among primates, an order with many endangered species, the two contexts can be hard to disentangle from one another, which carries important conservation implications. Callithrix marmosets give us a unique glimpse of genetic hybridization effects under distinct natural and human-induced contexts. Here, we use a 44 autosomal microsatellite marker panel to examine genome-wide admixture levels and introgression at a natural C. jacchus and C. penicillata species border along the São Francisco River in NE Brazil and in an area of Rio de Janeiro state where humans introduced these species exotically. Additionally, we describe for the first time autosomal genetic diversity in wild C. penicillata and expand previous C. jacchus genetic data. We characterize admixture within the natural zone as bimodal where hybrid ancestry is biased toward one parental species or the other. We also show evidence that São Francisco River islands are gateways for bidirectional gene flow across the species border. In the anthropogenic zone, marmosets essentially form a hybrid swarm with intermediate levels of admixture, likely from the absence of strong physical barriers to interspecific breeding. Our data show that while hybridization can occur naturally, the presence of physical, even if leaky, barriers to hybridization is important for maintaining species genetic integrity. Thus, we suggest further study of hybridization under different contexts to set well informed conservation guidelines for hybrid populations that often fit somewhere between "natural" and "man-made."

  14. Natural and Anthropogenic Hybridization in Two Species of Eastern Brazilian Marmosets (Callithrix jacchus and C. penicillata)

    Science.gov (United States)

    Malukiewicz, Joanna; Boere, Vanner; Fuzessy, Lisieux F.; Grativol, Adriana D.; de Oliveira e Silva, Ita; Pereira, Luiz C. M.; Ruiz-Miranda, Carlos R.; Valença, Yuri M.; Stone, Anne C.

    2015-01-01

    Animal hybridization is well documented, but evolutionary outcomes and conservation priorities often differ for natural and anthropogenic hybrids. Among primates, an order with many endangered species, the two contexts can be hard to disentangle from one another, which carries important conservation implications. Callithrix marmosets give us a unique glimpse of genetic hybridization effects under distinct natural and human-induced contexts. Here, we use a 44 autosomal microsatellite marker panel to examine genome-wide admixture levels and introgression at a natural C. jacchus and C. penicillata species border along the São Francisco River in NE Brazil and in an area of Rio de Janeiro state where humans introduced these species exotically. Additionally, we describe for the first time autosomal genetic diversity in wild C. penicillata and expand previous C. jacchus genetic data. We characterize admixture within the natural zone as bimodal where hybrid ancestry is biased toward one parental species or the other. We also show evidence that São Francisco River islands are gateways for bidirectional gene flow across the species border. In the anthropogenic zone, marmosets essentially form a hybrid swarm with intermediate levels of admixture, likely from the absence of strong physical barriers to interspecific breeding. Our data show that while hybridization can occur naturally, the presence of physical, even if leaky, barriers to hybridization is important for maintaining species genetic integrity. Thus, we suggest further study of hybridization under different contexts to set well informed conservation guidelines for hybrid populations that often fit somewhere between “natural” and “man-made.” PMID:26061111

  15. Hybridization, agency discretion, and implementation of the U.S. Endangered Species Act.

    Science.gov (United States)

    Lind-Riehl, Jennifer F; Mayer, Audrey L; Wellstead, Adam M; Gailing, Oliver

    2016-12-01

    The U.S. Endangered Species Act (ESA) requires that the "best available scientific and commercial data" be used to protect imperiled species from extinction and preserve biodiversity. However, it does not provide specific guidance on how to apply this mandate. Scientific data can be uncertain and controversial, particularly regarding species delineation and hybridization issues. The U.S. Fish and Wildlife Service (FWS) had an evolving hybrid policy to guide protection decisions for individuals of hybrid origin. Currently, this policy is in limbo because it resulted in several controversial conservation decisions in the past. Biologists from FWS must interpret and apply the best available science to their recommendations and likely use considerable discretion in making recommendations for what species to list, how to define those species, and how to recover them. We used semistructured interviews to collect data on FWS biologists' use of discretion to make recommendations for listed species with hybridization issues. These biologists had a large amount of discretion to determine the best available science and how to interpret it but generally deferred to the scientific consensus on the taxonomic status of an organism. Respondents viewed hybridization primarily as a problem in the context of the ESA, although biologists who had experience with hybridization issues were more likely to describe it in more nuanced terms. Many interviewees expressed a desire to continue the current case-by-case approach for handling hybridization issues, but some wanted more guidance on procedures (i.e., a "flexible" hybrid policy). Field-level information can provide critical insight into which policies are working (or not working) and why. The FWS biologists' we interviewed had a high level of discretion, which greatly influenced ESA implementation, particularly in the context of hybridization. © 2016 Society for Conservation Biology.

  16. Evidence for the robustness of protein complexes to inter-species hybridization.

    Directory of Open Access Journals (Sweden)

    Jean-Baptiste Leducq

    Full Text Available Despite the tremendous efforts devoted to the identification of genetic incompatibilities underlying hybrid sterility and inviability, little is known about the effect of inter-species hybridization at the protein interactome level. Here, we develop a screening platform for the comparison of protein-protein interactions (PPIs among closely related species and their hybrids. We examine in vivo the architecture of protein complexes in two yeast species (Saccharomyces cerevisiae and Saccharomyces kudriavzevii that diverged 5-20 million years ago and in their F1 hybrids. We focus on 24 proteins of two large complexes: the RNA polymerase II and the nuclear pore complex (NPC, which show contrasting patterns of molecular evolution. We found that, with the exception of one PPI in the NPC sub-complex, PPIs were highly conserved between species, regardless of protein divergence. Unexpectedly, we found that the architecture of the complexes in F1 hybrids could not be distinguished from that of the parental species. Our results suggest that the conservation of PPIs in hybrids likely results from the slow evolution taking place on the very few protein residues involved in the interaction or that protein complexes are inherently robust and may accommodate protein divergence up to the level that is observed among closely related species.

  17. Shift in precipitation regime promotes interspecific hybridization of introduced Coffea species.

    Science.gov (United States)

    Gomez, Céline; Despinoy, Marc; Hamon, Serge; Hamon, Perla; Salmon, Danyela; Akaffou, Doffou Sélastique; Legnate, Hyacinthe; de Kochko, Alexandre; Mangeas, Morgan; Poncet, Valérie

    2016-05-01

    The frequency of plant species introductions has increased in a highly connected world, modifying species distribution patterns to include areas outside their natural ranges. These introductions provide the opportunity to gain new insight into the importance of flowering phenology as a component of adaptation to a new environment. Three Coffea species, C. arabica, C. canephora (Robusta), and C. liberica, native to intertropical Africa have been introduced to New Caledonia. On this archipelago, a secondary contact zone has been characterized where these species coexist, persist, and hybridize spontaneously. We investigated the impact of environmental changes undergone by each species following its introduction in New Caledonia on flowering phenology and overcoming reproductive barriers between sister species. We developed species distribution models and compared both environmental envelopes and climatic niches between native and introduced hybrid zones. Flowering phenology was monitored in a population in the hybrid zone along with temperature and precipitation sequences recorded at a nearby weather station. The extent and nature of hybridization events were characterized using chloroplast and nuclear microsatellite markers. The three Coffea species encountered weak environmental suitability compared to their native ranges when introduced to New Caledonia, especially C. arabica and C. canephora. The niche of the New Caledonia hybrid zone was significantly different from all three species' native niches based on identity tests (I Similarity and D Schoener's Similarity Indexes). This area appeared to exhibit intermediate conditions between the native conditions of the three species for temperature-related variables and divergent conditions for precipitation-related ones. Flowering pattern in these Coffea species was shown to have a strong genetic component that determined the time between the triggering rain and anthesis (flower opening), specific to each species

  18. Widespread hybridization and bidirectional introgression in sympatric species of coral reef fish

    KAUST Repository

    Harrison, Hugo B.

    2017-10-28

    Coral reefs are highly diverse ecosystems, where numerous closely related species often coexist. How new species arise and are maintained in these high geneflow environments have been long-standing conundrums. Hybridization and patterns of introgression between sympatric species provide a unique insight into the mechanisms of speciation and the maintenance of species boundaries. In this study, we investigate the extent of hybridization between two closely related species of coral reef fish: the common coral trout (Plectropomus leopardus) and the bar-cheek coral trout (Plectropomus maculatus). Using a complementary set of 25 microsatellite loci, we distinguish pure genotype classes from first- and later-generation hybrids, identifying 124 interspecific hybrids from a collection of 2,991 coral trout sampled in inshore and mid-shelf reefs of the southern Great Barrier Reef. Hybrids were ubiquitous among reefs, fertile and spanned multiple generations suggesting both ecological and evolutionary processes are acting to maintain species barriers. We elaborate on these finding to investigate the extent of genomic introgression and admixture from 2,271 SNP loci recovered from a ddRAD library of pure and hybrid individuals. An analysis of genomic clines on recovered loci indicates that 261 SNP loci deviate from a model of neutral introgression, of which 132 indicate a pattern of introgression consistent with selection favouring both hybrid and parental genotypes. Our findings indicate genome-wide, bidirectional introgression between two sympatric species of coral reef fishes and provide further support to a growing body of evidence for the role of hybridization in the evolution of coral reef fishes.

  19. Hybridization in the Ensatina Ring Species, Strong selection against hybrids at a hybrid zone in the ensatina ring species complex and its evolutionary implications

    Energy Technology Data Exchange (ETDEWEB)

    Alexandrino, Joao; Baird, Stuart J.E.; Lawson, Lucinda; Macey, J. Robert; Moritz, Craig; Wake, David B.

    2005-04-22

    The analysis of interactions between lineages at varying levels of genetic divergence can provide insights into the process of speciation through the accumulation of incompatible mutations. Ring species, and especially the Ensatina eschscholtzii system exemplify this approach. The plethodontid salamanders Ensatina eschscholtzii xanthoptica and Ensatina eschscholtzii platensis hybridize in the Central Sierran foothills of California. We compared the genetic structure across two transects (southern and northern Calaveras Co.), one of which was re-sampled over 20 years, and examined diagnostic molecular markers (eight allozyme loci and mitochondrial DNA) and a diagnostic quantitative trait (color pattern). Key results across all studies were: (i) cline centers for all markers were coincident and the zones were narrow, with width estimates of 730m to 2000m; (ii) cline centers at the northern Calaveras transect were coincident between 1981 and 2001, demonstrating repeatability over 5 generations; (iii) there are very few if any putative F1's, but a relatively high number of backcrossed individuals (57-86 percent) in the central portion of transects; (iv) we found substantial linkage disequilibrium in all three studies and strong heterozygote deficit both in northern Calaveras, in 2001, and southern Calaveras. Both linkage disequilibrium and heterozygote deficit show maximum values near the center of the zones (R and Fis, approx. equal to 0.5). Using estimates of cline width and dispersal, we infer strong selection against hybrids (s* approx. equal to 46-75 percent). This is sufficient to promote accumulation of differences at loci that are neutral or under divergent selection, but would still allow for introgression of adaptive alleles. The evidence for strong, but incomplete isolation across this centrally located contact is consistent with theory suggesting a gradual increase in postzygotic incompatibility between allopatric populations subject to divergent

  20. Species by environment interactions affect pyrrolizidine alkaloid expression in Senecio jacobaea, Senecio aquaticus, and their hybrids.

    Science.gov (United States)

    Kirk, Heather; Vrieling, Klaas; Van Der Meijden, Eddy; Klinkhamer, Peter G L

    2010-04-01

    We examined the effects of water and nutrient availability on the expression of the defense pyrrolizidine alkaloids (PAs) in Senecio jacobaea and S. aquaticus. Senecio jacobaea, and S. aquaticus are adapted to different natural habitats, characterized by differing abiotic conditions and different selection pressures from natural enemies. We tested if PA concentration and diversity are plastic over a range of water and nutrient treatments, and also whether such plasticity is dependent on plant species. We also tested the hypothesis that hybridization may contribute to PA diversity within plants, by comparing PA expression in parental species to that in artificially generated F(1) hybrids, and also in later generation natural hybrids between S. jacobaea and S. aquaticus. We showed that total PA concentration in roots and shoots is not dependent on species, but that species determines the pattern of PA diversification. Pyrrolizidine alkaloid diversity and concentration are both dependent on environmental factors. Hybrids produce a putatively novel PA, and this PA is conserved in natural hybrids, that are backcrossed to S. jacobaea. Natural hybrids that are backcrossed several times to S. jacobaea are with regard to PA diversity significantly different from S. jacobaea but not from S. aquaticus, while F(1) hybrids are in all cases more similar to S. jacobaea. These results collectively suggest that PA diversity is under the influence of natural selection.

  1. Rape and the prevalence of hybrids in broadly sympatric species: a case study using albatrosses

    Directory of Open Access Journals (Sweden)

    Sievert Rohwer

    2014-06-01

    Full Text Available Conspecific rape often increases male reproductive success. However, the haste and aggression of forced copulations suggests that males may sometimes rape heterospecific females, thus making rape a likely, but undocumented, source of hybrids between broadly sympatric species. We present evidence that heterospecific rape may be the source of hybrids between Black-footed and Laysan Albatrosses (Phoebastria nigripes, and P. immutabilis, respectively. Extensive field studies have shown that paired (but not unpaired males of both of these albatross species use rape as a supplemental reproductive strategy. Between species differences in size, timing of laying, and aggressiveness suggest that Black-footed Albatrosses should be more successful than Laysan Albatrosses in heteropspecific rape attempts, and male Black-footed Albatrosses have been observed attempting to force copulations on female Laysan Albatrosses. Nuclear markers showed that the six hybrids we studied were F1s and mitochondrial markers showed that male Black-footed Albatrosses sired all six hybrids. Long-term gene exchange between these species has been from Black-footed Albatrosses into Laysan Albatrosses, suggesting that the siring asymmetry found in our hybrids has long persisted. If hybrids are sired in heterospecific rapes, they presumably would be raised and sexually imprinted on Laysan Albatrosses, and two unmated hybrids in a previous study courted only Laysan Albatrosses.

  2. Sunflower seed allergy.

    Science.gov (United States)

    Ukleja-Sokołowska, Natalia; Gawrońska-Ukleja, Ewa; Żbikowska-Gotz, Magdalena; Bartuzi, Zbigniew; Sokołowski, Łukasz

    2016-09-01

    Sunflower seeds are a rare source of allergy, but several cases of occupational allergies to sunflowers have been described. Sunflower allergens on the whole, however, still await precise and systematic description. We present an interesting case of a 40-year-old male patient, admitted to hospital due to shortness of breath and urticaria, both of which appeared shortly after the patient ingested sunflower seeds. Our laryngological examination revealed swelling of the pharynx with retention of saliva and swelling of the mouth and tongue. During diagnostics, 2 months later, we found that skin prick tests were positive to mugwort pollen (12/9 mm), oranges (6/6 mm), egg protein (3/3 mm), and hazelnuts (3/3 mm). A native prick by prick test with sunflower seeds was strongly positive (8/5 mm). Elevated concentrations of specific IgE against weed mix (inc. lenscale, mugwort, ragweed) allergens (1.04 IU/mL), Artemisia vulgaris (1.36 IU/mL), and Artemisia absinthium (0.49 IU/mL) were found. An ImmunoCap ISAC test found an average level of specific IgE against mugwort pollen allergen component Art v 1 - 5,7 ISU-E, indicating an allergy to mugwort pollen and low to medium levels of specific IgE against lipid transfer proteins (LTP) found in walnuts, peanuts, mugwort pollen, and hazelnuts. Through the ISAC inhibition test we proved that sunflower seed allergen extracts contain proteins cross-reactive with patients' IgE specific to Art v 1, Art v 3, and Jug r 3. Based on our results and the clinical pattern of the disease we confirmed that the patient is allergic to mugwort pollen and that he had an anaphylactic reaction as a result of ingesting sunflower seeds. We suspected that hypersensitivity to sunflower LTP and defensin-like proteins, both cross-reactive with mugwort pollen allergens, were the main cause of the patient's anaphylactic reaction. © The Author(s) 2016.

  3. Evidence for hybridization and introgression within a species-rich oak (Quercus spp. community

    Directory of Open Access Journals (Sweden)

    Finkeldey Reiner

    2007-11-01

    Full Text Available Abstract Background Analysis of interspecific gene flow is crucial for the understanding of speciation processes and maintenance of species integrity. Oaks (genus Quercus, Fagaceae are among the model species for the study of hybridization. Natural co-occurrence of four closely related oak species is a very rare case in the temperate forests of Europe. We used both morphological characters and genetic markers to characterize hybridization in a natural community situated in west-central Romania and which consists of Quercus robur, Q. petraea, Q. pubescens, and Q. frainetto, respectively. Results On the basis of pubescence and leaf morphological characters ~94% of the sampled individuals were assigned to pure species. Only 16 (~6% individual trees exhibited intermediate morphologies or a combination of characters of different species. Four chloroplast DNA haplotypes were identified in the study area. The distribution of haplotypes within the white oak complex showed substantial differences among species. However, the most common haplotypes were present in all four species. Furthermore, based on a set of 7 isozyme and 6 microsatellite markers and using a Bayesian admixture analysis without any a priori information on morphology we found that four genetic clusters best fit the data. There was a very good correspondence of each species with one of the inferred genetic clusters. The estimated introgression level varied markedly between pairs of species ranging from 1.7% between Q. robur and Q. frainetto to 16.2% between Q. pubescens and Q. frainetto. Only nine individuals (3.4% appeared to be first-generation hybrids. Conclusion Our data indicate that natural hybridization has occurred at relatively low rates. The different levels of gene flow among species might be explained by differences in flowering time and spatial position within the stand. In addition, a partial congruence between phenotypically and genetically intermediate individuals was

  4. Mechanisms of Transmission Ratio Distortion at Hybrid Sterility Loci Within and Between Mimulus Species.

    Science.gov (United States)

    Kerwin, Rachel E; Sweigart, Andrea L

    2017-09-21

    Hybrid incompatibilities are a common correlate of genomic divergence and a potentially important contributor to reproductive isolation. However, we do not yet have a detailed understanding of how hybrid incompatibility loci function and evolve within their native species, or why they are dysfunctional in hybrids. Here, we explore these issues for a well-studied, two-locus hybrid incompatibility between hybrid male sterility 1 (hms1) and hybrid male sterility 2 (hms2) in the closely related yellow monkeyflower species Mimulus guttatus and M. nasutus By performing reciprocal backcrosses with introgression lines, we find evidence for gametic expression of the hms1-hms2 incompatibility. Surprisingly, however, hybrid transmission ratios at hms1 do not reflect this incompatibility, suggesting additional mechanisms counteract the effects of gametic sterility. Indeed, our backcross experiment shows hybrid transmission bias toward M. guttatus through both pollen and ovules, an effect that is particularly strong when hms2 is homozygous for M. nasutus alleles. In contrast, we find little evidence for hms1 transmission bias in crosses within M. guttatus, providing no indication of selfish evolution at this locus. Although we do not yet have sufficient genetic resolution to determine if hybrid sterility and transmission ratio distortion map to the same loci, our preliminary fine-mapping uncovers a genetically independent hybrid lethality system involving at least two loci linked to hms1 This fine-scale dissection of transmission ratio distortion at hms1 and hms2 provides insight into genomic differentiation between closely related Mimulus species and reveals multiple mechanisms of hybrid dysfunction. Copyright © 2017, G3: Genes, Genomes, Genetics.

  5. Molecular data reveal complex hybridization and a cryptic species of neotropical wild cat.

    Science.gov (United States)

    Trigo, Tatiane C; Schneider, Alexsandra; de Oliveira, Tadeu G; Lehugeur, Livia M; Silveira, Leandro; Freitas, Thales R O; Eizirik, Eduardo

    2013-12-16

    Hybridization among animal species has recently become more recognized as an important phenomenon, especially in the context of recent radiations. Here we show that complex hybridization has led to contrasting patterns of genomic composition among closely related species of the Neotropical cat genus Leopardus. We show strong evidence of ancient hybridization and introgression between the pampas cat (L. colocolo) and northeastern populations of tigrina (L. tigrinus), leading to remarkable cytonuclear discordance in the latter. In contrast, southern tigrina populations show recent and continuing hybridization with Geoffroy's cat (L. geoffroyi), leading to extreme levels of interspecific admixture at their contact zone. Finally, we demonstrate that two seemingly continuous Brazilian tigrina populations show no evidence of ongoing gene flow between them, leading us to support their formal recognition as distinct species, namely L. tigrinus in the northeast and L. guttulus in the south. Copyright © 2013 Elsevier Ltd. All rights reserved.

  6. A crop model-based approach for sunflower yields

    Directory of Open Access Journals (Sweden)

    João Guilherme Dal Belo Leite

    2014-10-01

    Full Text Available Pushed by the Brazilian biodiesel policy, sunflower (Helianthus annuus L. production is becoming increasingly regarded as an option to boost farmers' income, particularly under semi-arid conditions. Biodiesel related opportunities increase the demand for decision-making information at different levels, which could be met by simulation models. This study aimed to evaluate the performance of the crop model OILCROP-SUN to simulate sunflower development and growth under Brazilian conditions and to explore sunflower water- and nitrogen-limited, water-limited and potential yield and yield variability over an array of sowing dates in the northern region of the state of Minas Gerais, Brazil. For model calibration, an experiment was conducted in which two sunflower genotypes (H358 and E122 were cultivated in a clayey soil. Growth components (leaf area index, above ground biomass, grain yield and development stages (crop phenology were measured. A database composed of 27 sunflower experiments from five Brazilian regions was used for model evaluation. The spatial yield distribution of sunflower was mapped using ordinary kriging in ArcGIS. The model simulated sunflower grain productivity satisfactorily (Root Mean Square Error ≈ 13 %. Simulated yields were relatively high (1,750 to 4,250 kg ha-1 and the sowing window was fairly wide (Oct to Feb for northwestern locations, where sunflower could be cultivated as a second crop (double cropping at the end of the rainy season. The hybrid H358 had higher yields for all simulated sowing dates, growth conditions and selected locations.

  7. Invasive hybridization in a threatened species is accelerated by climate change

    Science.gov (United States)

    Muhlfeld, Clint C.; Kovach, Ryan P.; Jones, Leslie A.; Al-Chokhachy, Robert K.; Boyer, Matthew C.; Leary, Robb F.; Lowe, Winsor H.; Luikart, Gordon; Allendorf, Fred W.

    2014-01-01

    Climate change will decrease worldwide biodiversity through a number of potential pathways, including invasive hybridization (cross-breeding between invasive and native species). How climate warming influences the spread of hybridization and loss of native genomes poses difficult ecological and evolutionary questions with little empirical information to guide conservation management decisions. Here we combine long-term genetic monitoring data with high-resolution climate and stream temperature predictions to evaluate how recent climate warming has influenced the spatio-temporal spread of human-mediated hybridization between threatened native westslope cutthroat trout (Oncorhynchus clarkii lewisi) and non-native rainbow trout (Oncorhynchus mykiss), the world’s most widely introduced invasive fish. Despite widespread release of millions of rainbow trout over the past century within the Flathead River system, a large relatively pristine watershed in western North America, historical samples revealed that hybridization was prevalent only in one (source) population. During a subsequent 30-year period of accelerated warming, hybridization spread rapidly and was strongly linked to interactions between climatic drivers—precipitation and temperature—and distance to the source population. Specifically, decreases in spring precipitation and increases in summer stream temperature probably promoted upstream expansion of hybridization throughout the system. This study shows that rapid climate warming can exacerbate interactions between native and non-native species through invasive hybridization, which could spell genomic extinction for many species.

  8. Climate-Driven Reshuffling of Species and Genes: Potential Conservation Roles for Species Translocations and Recombinant Hybrid Genotypes

    Directory of Open Access Journals (Sweden)

    Jon Mark Scriber

    2013-12-01

    Full Text Available Comprising 50%–75% of the world’s fauna, insects are a prominent part of biodiversity in communities and ecosystems globally. Biodiversity across all levels of biological classifications is fundamentally based on genetic diversity. However, the integration of genomics and phylogenetics into conservation management may not be as rapid as climate change. The genetics of hybrid introgression as a source of novel variation for ecological divergence and evolutionary speciation (and resilience may generate adaptive potential and diversity fast enough to respond to locally-altered environmental conditions. Major plant and herbivore hybrid zones with associated communities deserve conservation consideration. This review addresses functional genetics across multi-trophic-level interactions including “invasive species” in various ecosystems as they may become disrupted in different ways by rapid climate change. “Invasive genes” (into new species and populations need to be recognized for their positive creative potential and addressed in conservation programs. “Genetic rescue” via hybrid translocations may provide needed adaptive flexibility for rapid adaptation to environmental change. While concerns persist for some conservationists, this review emphasizes the positive aspects of hybrids and hybridization. Specific implications of natural genetic introgression are addressed with a few examples from butterflies, including transgressive phenotypes and climate-driven homoploid recombinant hybrid speciation. Some specific examples illustrate these points using the swallowtail butterflies (Papilionidae with their long-term historical data base (phylogeographical diversity changes and recent (3-decade climate-driven temporal and genetic divergence in recombinant homoploid hybrids and relatively recent hybrid speciation of Papilio appalachiensis in North America. Climate-induced “reshuffling” (recombinations of species composition, genotypes

  9. Growth rhythms in sunflower ( Helianthus annuus L.) in response to ...

    African Journals Online (AJOL)

    Sunflower hybrids maintain high level of stability in a variety of environments. Environmental variations affect and modify plant attributes like growth, development and assimilation through physio-morphic functions, thus modifying plant phenology. Field experiments, one each in spring and autumn, were conducted at Pir ...

  10. Growth rhythms in sunflower (Helianthus annuus L.) in response to ...

    African Journals Online (AJOL)

    STORAGESEVER

    2010-04-12

    Apr 12, 2010 ... affect and modify plant attributes like growth, development and assimilation through physio-morphic functions, thus modifying plant ... and 2008) to document the effect of environmental variations on growth rhythms of sunflower hybrids. ..... temperature and maximum intercepted solar radiation at these crop ...

  11. Growth rhythms in sunflower ( Helianthus annuus L.) in response to ...

    African Journals Online (AJOL)

    Four Sunflower hybrids, Alisson-RM, Parasio-24, MG-2 and S-278 were planted in randomized complete block design with four replications. The data based on physiological attributes like leaf area (LA), specific leaf area (SLA), crop growth rate (CGR) and net assimilation rate (NAR) at 10 days interval after complete ...

  12. Absence of postzygotic isolating mechanisms: evidence from experimental hybridization between two species of tropical sea urchins*

    Science.gov (United States)

    Rahman, M. Aminur; Uehara, Tsuyoshi; Arshad, Aziz; Yusoff, Fatimah Md.; Shamsudin, Mariana Nor

    2012-01-01

    Two reef margin species of tropical sea urchins, Echinometra sp. C (Ec) and Echinometra oblonga (Eo), occur sympatrically on Okinawa intertidal reefs in southern Japan. Hybridization between these species was examined through a series of cross-fertilization experiments. At limited sperm concentrations, where conspecific crosses reached near 100% fertilization, both heterospecific crosses showed high fertilization rates (81%–85%). The compatibility of the gametes demonstrated that if gamete recognition molecules are involved in fertilization of these species, they are not strongly species-specific. We found that conspecific crosses reached peak fertilization levels much faster than did heterospecific crosses, indicating the presence of a prezygotic barrier to hybridization in the gametes. Larval survival, metamorphosis, and juvenile and adult survival of hybrid groups were nearly identical to those of their parent species. Hybrids from crosses in both directions developed normally through larval stages to sexually mature adults, indicating that neither gametic incompatibility nor hybrid inviability appeared to maintain reproductive isolation between these species. In adults, Ec×Ec crosses gave the highest live weight, followed by Eo (ova)×Ec (sperm), Ec (ova)×Eo (sperm), and Eo×Eo. Other growth performance measures (viz., test size, Aristotle’s lantern length, and gonad index) of hybrid groups and their parental siblings showed the same trends. The phenotypic color patterns of the hybrids were closer to the maternal coloration, whereas spine length, tube-foot and gonad spicule characteristics, pedicellaria valve length, and gamete sizes showed intermediate features. Adult F1 hybrids were completely fertile and displayed high fertilization success in F1 backcrosses, eliminating the likelihood that hybrid sterility is a postzygotic mechanism of reproductive isolation. Conversely, intensive surveys failed to find hybrid individuals in the field, suggesting the

  13. Absence of postzygotic isolating mechanisms: evidence from experimental hybridization between two species of tropical sea urchins.

    Science.gov (United States)

    Rahman, M Aminur; Uehara, Tsuyoshi; Arshad, Aziz; Yusoff, Fatimah Md; Shamsudin, Mariana Nor

    2012-10-01

    Two reef margin species of tropical sea urchins, Echinometra sp. C (Ec) and Echinometra oblonga (Eo), occur sympatrically on Okinawa intertidal reefs in southern Japan. Hybridization between these species was examined through a series of cross-fertilization experiments. At limited sperm concentrations, where conspecific crosses reached near 100% fertilization, both heterospecific crosses showed high fertilization rates (81%-85%). The compatibility of the gametes demonstrated that if gamete recognition molecules are involved in fertilization of these species, they are not strongly species-specific. We found that conspecific crosses reached peak fertilization levels much faster than did heterospecific crosses, indicating the presence of a prezygotic barrier to hybridization in the gametes. Larval survival, metamorphosis, and juvenile and adult survival of hybrid groups were nearly identical to those of their parent species. Hybrids from crosses in both directions developed normally through larval stages to sexually mature adults, indicating that neither gametic incompatibility nor hybrid inviability appeared to maintain reproductive isolation between these species. In adults, Ec×Ec crosses gave the highest live weight, followed by Eo (ova)×Ec (sperm), Ec (ova)×Eo (sperm), and Eo×Eo. Other growth performance measures (viz., test size, Aristotle's lantern length, and gonad index) of hybrid groups and their parental siblings showed the same trends. The phenotypic color patterns of the hybrids were closer to the maternal coloration, whereas spine length, tube-foot and gonad spicule characteristics, pedicellaria valve length, and gamete sizes showed intermediate features. Adult F(1) hybrids were completely fertile and displayed high fertilization success in F(1) backcrosses, eliminating the likelihood that hybrid sterility is a postzygotic mechanism of reproductive isolation. Conversely, intensive surveys failed to find hybrid individuals in the field, suggesting the

  14. Sunflower mega-environments in Serbia revealed by GGE biplot analysis

    Directory of Open Access Journals (Sweden)

    Balalić Igor

    2013-01-01

    Full Text Available Sunflower mega-environment analysis was conducted for the grain yield data of 20 hybrids and 19 test locations during 2006, and 20 hybrids and 16 test locations during 2007. Combined data included 15 hybrids and 9 test locations common for both years and it was analyzed as balanced experiment. The analysis of variance components showed that hybrid by location interaction explained 2.74, 5.8, and 3.72 times more variation than hybrid, for grain yield, for 2006, 2007, combined data, respectively, and indicated potential mega-environment existence. Our results showed the existence of two mega-environments in Serbia sunflower growing region: (1 Kula Vitovnica, Aleksa Šantić, Sombor and (2 Rimski Šančevi, Kikinda. It has been concluded that if we want promising sunflower hybrids to be optimally used, they should be cropped differently for the two determined mega-environments.

  15. [Species characteristics of sperm morphology in representatives of the Carnivora order in relation to their hybridization].

    Science.gov (United States)

    Steklenev, E P

    1975-01-01

    Spermium morphology was studied in 7 species of Carnivora representatives. Their clear distinctions reflecting genetic relations between certain species of animals in the zoological series are established. Genetical determination of the spermium morphology is confirmed by the data of the hybridization analysis.

  16. Hybridization among three native North American Canis species in a region of natural sympatry.

    Directory of Open Access Journals (Sweden)

    Frank Hailer

    2008-10-01

    Full Text Available Population densities of many species throughout the world are changing due to direct persecution as well as anthropogenic habitat modification. These changes may induce or increase the frequency of hybridization among taxa. If extensive, hybridization can threaten the genetic integrity or survival of endangered species. Three native species of the genus Canis, coyote (C. latrans, Mexican wolf (C. lupus baileyi and red wolf (C. rufus, were historically sympatric in Texas, United States. Human impacts caused the latter two to go extinct in the wild, although they survived in captive breeding programs. Morphological data demonstrate historic reproductive isolation between all three taxa. While the red wolf population was impacted by introgressive hybridization with coyotes as it went extinct in the wild, the impact of hybridization on the Texas populations of the other species is not clear.We surveyed variation at maternally and paternally inherited genetic markers (mitochondrial control region sequence and Y chromosome microsatellites in coyotes from Texas, Mexican wolves and red wolves from the captive breeding programs, and a reference population of coyotes from outside the historic red wolf range. Levels of variation and phylogenetic analyses suggest that hybridization has occasionally taken place between all three species, but that the impact on the coyote population is very small.Our results demonstrate that the factors driving introgressive hybridization in sympatric Texan Canis are multiple and complex. Hybridization is not solely determined by body size or sex, and density-dependent effects do not fully explain the observed pattern either. No evidence of hybridization was identified in the Mexican wolf captive breeding program, but introgression appears to have had a greater impact on the captive red wolves.

  17. Hybridization among three native North American Canis species in a region of natural sympatry.

    Science.gov (United States)

    Hailer, Frank; Leonard, Jennifer A

    2008-10-08

    Population densities of many species throughout the world are changing due to direct persecution as well as anthropogenic habitat modification. These changes may induce or increase the frequency of hybridization among taxa. If extensive, hybridization can threaten the genetic integrity or survival of endangered species. Three native species of the genus Canis, coyote (C. latrans), Mexican wolf (C. lupus baileyi) and red wolf (C. rufus), were historically sympatric in Texas, United States. Human impacts caused the latter two to go extinct in the wild, although they survived in captive breeding programs. Morphological data demonstrate historic reproductive isolation between all three taxa. While the red wolf population was impacted by introgressive hybridization with coyotes as it went extinct in the wild, the impact of hybridization on the Texas populations of the other species is not clear. We surveyed variation at maternally and paternally inherited genetic markers (mitochondrial control region sequence and Y chromosome microsatellites) in coyotes from Texas, Mexican wolves and red wolves from the captive breeding programs, and a reference population of coyotes from outside the historic red wolf range. Levels of variation and phylogenetic analyses suggest that hybridization has occasionally taken place between all three species, but that the impact on the coyote population is very small. Our results demonstrate that the factors driving introgressive hybridization in sympatric Texan Canis are multiple and complex. Hybridization is not solely determined by body size or sex, and density-dependent effects do not fully explain the observed pattern either. No evidence of hybridization was identified in the Mexican wolf captive breeding program, but introgression appears to have had a greater impact on the captive red wolves.

  18. Introgressive Hybridization of Schistosoma haematobium Group Species in Senegal: Species Barrier Break Down between Ruminant and Human Schistosomes

    OpenAIRE

    WEBSTER, B. L.; Diaw, O. T.; Seye, M M; Webster, J. P.; Rollinson, D

    2013-01-01

    BACKGROUND: Schistosomes are dioecious parasitic flatworms, which live in the vasculature of their mammalian definitive hosts. They are the causative agent of schistosomiasis, a disease of considerable medical and veterinary importance in tropical and subtropical regions. Schistosomes undergo a sexual reproductive stage within their mammalian host enabling interactions between different species, which may result in hybridization if the species involved are phylogenetically close. In Senegal, ...

  19. Incompatibility of nuclear and mitochondrial genomes causes hybrid sterility between two yeast species.

    Science.gov (United States)

    Lee, Hsin-Yi; Chou, Jui-Yu; Cheong, Liplee; Chang, Nai-Hsin; Yang, Shi-Yow; Leu, Jun-Yi

    2008-12-12

    Hybrids between species are usually unviable or sterile. One possible mechanism causing reproductive isolation is incompatibility between genes from different species. These "speciation" genes are interacting components that cannot function properly when mixed with alleles from other species. To test whether such genes exist in two closely related yeast species, we constructed hybrid lines in which one or two chromosomes were derived from Saccharomyces bayanus, and the rest were from Saccharomyces cerevisiae. We found that the hybrid line with Chromosome 13 substitution was completely sterile and identified Aep2, a mitochondrial protein encoded on Chromosome 13, to cause the sporulation defect as S. bayanus AEP2 is incompatible with S. cerevisiae mitochondria. This is caused by the inability of S. bayanus Aep2 protein to regulate the translation of the S. cerevisiae OLI1 mRNA. We speculate that AEP2 and OLI1 have evolved during the adaptation of S. bayanus to nonfermentable carbon sources, thereby driving speciation.

  20. Putative hybrids between two Anisakis cryptic species: molecular genotyping using High Resolution Melting.

    Science.gov (United States)

    Cavallero, S; Costa, A; Caracappa, S; Gambetta, B; D'Amelio, S

    2014-11-01

    The genus Anisakis includes nine recognized species and the complex of cryptic species Anisakis simplex s. l. is often associated with the human disease known as anisakiasis. During the last decades the use of nuclear ribosomal ITS allowed the identification and description of numerous anisakid nematodes and the discovery of recombinant genotypes or putative hybrids even in other parasitic helminths, such as those between A. simplex sensu stricto and A. pegreffii. The existence of pure hybrids of the two sibling species has been long debated due to the large recovery of larval forms from sympatric areas and the rare observation of adult hybrids. The aims of the present report were to identify anisakid nematodes collected from Stenella coeruleoalba using PCR-RFLP of ITS and to focus the interest on hybrid forms using a High Resolution Melting (HRM) and direct sequencing analyses, since the new record of putative hybrid at adult stage. The PCR-RFLP analysis enabled to identify A. simplex s.s., A. pegreffii, the heterozygous genotype of the two species and A. physeteris. The use of the genotyping approach based on HRM confirmed the profiles of the two species A. simplex s.s. and A. pegreffii, and of the hybrid individuals. The new record of adult hybrids in definitive hosts rekindles the long debate about their existence and their evolutionary meaning. Since the reproductive isolation between A. simplex s.s. and A. pegreffii is the assumption for their existence as separated species, the use of alternative molecular markers and population genetic studies on adult anisakids are recommended. Copyright © 2014 Elsevier Inc. All rights reserved.

  1. Asymmetrical gene flow in a hybrid zone of Hawaiian Schiedea (Caryophyllaceae species with contrasting mating systems.

    Directory of Open Access Journals (Sweden)

    Lisa E Wallace

    Full Text Available Asymmetrical gene flow, which has frequently been documented in naturally occurring hybrid zones, can result from various genetic and demographic factors. Understanding these factors is important for determining the ecological conditions that permitted hybridization and the evolutionary potential inherent in hybrids. Here, we characterized morphological, nuclear, and chloroplast variation in a putative hybrid zone between Schiedea menziesii and S. salicaria, endemic Hawaiian species with contrasting breeding systems. Schiedea menziesii is hermaphroditic with moderate selfing; S. salicaria is gynodioecious and wind-pollinated, with partially selfing hermaphrodites and largely outcrossed females. We tested three hypotheses: 1 putative hybrids were derived from natural crosses between S. menziesii and S. salicaria, 2 gene flow via pollen is unidirectional from S. salicaria to S. menziesii and 3 in the hybrid zone, traits associated with wind pollination would be favored as a result of pollen-swamping by S. salicaria. Schiedea menziesii and S. salicaria have distinct morphologies and chloroplast genomes but are less differentiated at the nuclear loci. Hybrids are most similar to S. menziesii at chloroplast loci, exhibit nuclear allele frequencies in common with both parental species, and resemble S. salicaria in pollen production and pollen size, traits important to wind pollination. Additionally, unlike S. menziesii, the hybrid zone contains many females, suggesting that the nuclear gene responsible for male sterility in S. salicaria has been transferred to hybrid plants. Continued selection of nuclear genes in the hybrid zone may result in a population that resembles S. salicaria, but retains chloroplast lineage(s of S. menziesii.

  2. [Establishing the regeneration system of sunflower].

    Science.gov (United States)

    Wang, Yuanyuan; Li, Caifeng; Zhang, Yifei; Chen, Yeting; Zhao, Liying; Yue, Peng; Teng, Xiangyong; Wang, Nanbo

    2011-09-01

    In order to establish a high efficient regeneration system of sunflower, we optimized the process of callus induction, differentiation and rooting by screening the optimum genotype, explant materials, hormone and cytokine concentration and additives. The results indicated that hybrid sunflowers were easier to regenerate than selfing ones; The best explant was four days cotyledon. The optimum induction medium was Murashige and Skoog (MS) + 2.0 mg/L 6-benzyladenine (6-BA) + 0.5 mg/L naphthaleneacetic acid (NAA) + 1.0 mg/L kinetin (KT). The maximum rate of callus induction was 100%. The optimum differentiation medium was MS +0.2 mg/L 6-BA + 0.5 mg/L NAA + 0.3 mg/L KT + 0.3 mg/L silver nitrate (AgNO3) + 0.2 g/L active carbon (AC), and the buds differentiation rate was up to 71%. The best rooting culture medium was 1/2 MS + 0.6 mg/L indolebutyric acid (IBA). The highest rooting rate was 77%. The analysis of variance showed that genotype, explants growth time, different kinds and concentration of hormone, AC concentration had a significant effect on sunflower regeneration.

  3. Molecular detection of hybridization between sympatric kangaroo species in south-eastern Australia.

    Science.gov (United States)

    Neaves, L E; Zenger, K R; Cooper, D W; Eldridge, M D B

    2010-05-01

    Introgressive hybridization has traditionally been regarded as rare in many vertebrate groups, including mammals. Despite a propensity to hybridize in captivity, introgression has rarely been reported between wild sympatric macropodid marsupials. Here we investigate sympatric populations of western (Macropus fuliginosus) and eastern (Macropus giganteus) grey kangaroos through 12 autosomal microsatellite loci and 626 bp of the hypervariable mitochondrial DNA (mtDNA) control region. M. fuliginosus and M. giganteus within the region of sympatry corresponded, both genetically and morphologically, to their respective species elsewhere in their distributions. Of the 223 grey kangaroos examined, 7.6% displayed evidence of introgression, although no F1 hybrids were detected. In contrast to captive studies, there was no evidence for unidirectional hybridization in sympatric grey kangaroos. However, a higher portion of M. giganteus backcrosses existed within the sample compared with M. fuliginosus. Hybridization in grey kangaroos is reflective of occasional breakdowns in species boundaries, occurring throughout the region and potentially associated with variable conditions and dramatic reductions in densities. Such rare hybridization events allow populations to incorporate novel diversity while still retaining species integrity.

  4. Gene flow and hybridization between numerically imbalanced populations of two duck species in the Falkland Islands.

    Directory of Open Access Journals (Sweden)

    Kevin G McCracken

    Full Text Available Interspecific hybridization is common in plants and animals, particularly in waterfowl (Anatidae. One factor shown to contribute to hybridization is restricted mate choice, which can occur when two species occur in sympatry but one is rare. The Hubbs principle, or "desperation hypothesis," states that under such circumstances the rarer species is more likely to mate with heterospecifics. Here we report interspecific hybridization between two waterfowl species that coexist in broad sympatry and mixed flocks throughout southern South America. Speckled teal (Anas flavirostris and yellow-billed pintails (Anas georgica are abundant in continental South America, but in the Falkland Islands speckled teal outnumber yellow-billed pintails approximately ten to one. Using eight genetic loci (mtDNA and 7 nuclear introns coupled with Bayesian assignment tests and relatedness analysis, we identified a speckled teal x yellow-billed pintail F(1 hybrid female and her duckling sired by a male speckled teal. Although our sample in the Falkland Islands was small, we failed to identify unequivocal evidence of hybridization or introgression in a much larger sample from Argentina using a three-population "isolation with migration" coalescent analysis. While additional data are needed to determine if this event in the Falkland Islands was a rare singular occurrence, our results provide further support for the "desperation hypothesis," which states that scarcity in one population and abundance of another will often lead to hybridization.

  5. Rapid male-specific regulatory divergence and down regulation of spermatogenesis genes in Drosophila species hybrids.

    Directory of Open Access Journals (Sweden)

    Jennifer Ferguson

    Full Text Available In most crosses between closely related species of Drosophila, the male hybrids are sterile and show postmeiotic abnormalities. A series of gene expression studies using genomic approaches have found significant down regulation of postmeiotic spermatogenesis genes in sterile male hybrids. These results have led some to suggest a direct relationship between down regulation in gene expression and hybrid sterility. An alternative explanation to a cause-and-effect relationship between misregulation of gene expression and male sterility is rapid divergence of male sex regulatory elements leading to incompatible interactions in an interspecies hybrid genome. To test the effect of regulatory divergence in spermatogenesis gene expression, we isolated 35 fertile D. simulans strains with D. mauritiana introgressions in either the X, second or third chromosome. We analyzed gene expression in these fertile hybrid strains for a subset of spermatogenesis genes previously reported as significantly under expressed in sterile hybrids relative to D. simulans. We found that fertile autosomal introgressions can cause levels of gene down regulation similar to that of sterile hybrids. We also found that X chromosome heterospecific introgressions cause significantly less gene down regulation than autosomal introgressions. Our results provide evidence that rapid male sex gene regulatory divergence can explain misexpression of spermatogenesis genes in hybrids.

  6. On the origin of asexual species by means of hybridization and drift

    DEFF Research Database (Denmark)

    Hartfield, Matthew

    2016-01-01

    Several species of asexuals appear to have existed for millions of years. This is despite the prevalent view that natural selection is weakened without gene exchange, which should cause these organisms to rapidly go extinct. In theory, one can identify evolutionary long-lived asexuals from...... their allelic sequence divergence, also known as the 'Meselson effect', which leads to elevated within-individual diversity. Yet evidence that this phenomenon exists is mixed. Furthermore, several confounding factors can lead to similar outcomes, including the formation of asexual species by hybridization...... that the asexual L. pseudolactus is a hybrid between a sexual and an asexual species. After isolating out diversity arising from this hybridization, they find subsequent evidence for the Meselson effect. This study sets a new standard for differentiating between the complex causes and consequences of asexuality....

  7. IMPROVING WHEAT TRITICUM AESTIVUM L. BY INTERSPECIFIC AND INTERGENERIC HYBRIDIZATION WITH POACEAE FAMILY SPECIES

    Directory of Open Access Journals (Sweden)

    Czaplicki A.Z.

    2012-08-01

    Full Text Available The related species of the family Poaceae (Triticeae are the source of unprecedented new genes that allow the extension of genetic variation of common wheat Triticum aestivum L. These species have similar homoeologous chromosomes and rDNA sequences very similar to T. aestivum L. [1-3]. This allows the introgression of alien genes and their incorporation into the genomes A, B and D of wheat, where they can function permanently in the wheat genetic systems. Many of them have already been transferred to the varieties of T. aestivum L. [4].The experimental material consisted of 28 lines of winter wheat obtained using the interspecific and intergeneric hybridization of T. aestivum L. with alien species T. durum Desf., T. timopheevii Zhuk., Lolium perenne L. and Aegilops speltoides Taush. Among them, 15 lines were developed from the cross-combination with tetraploid species (AABB T. durum Desf., 4 lines from the combination with other tetraploid species of different genome composition (AAGG T. timopheevii Zhuk., 4 lines from cross with L. perenne L. and 5 lines were the double hybrids (three-generic derived with two related species, T. durum Desf. (AABB and Ae. speltoides Taush (BB.The anther culture method was used for obtaining DH lines from these interspecific and intergeneric hybrids. In in vitro culture 124 green plants were regenerated. The method of cluster analysis grouped hybrids in terms of comprehensive general similarity of the studied traits.

  8. Diversifying Sunflower Germplasm by Integration and Mapping of a Novel Male Fertility Restoration Gene

    Science.gov (United States)

    Liu, Zhao; Wang, Dexing; Feng, Jiuhuan; Seiler, Gerald J.; Cai, Xiwen; Jan, Chao-Chien

    2013-01-01

    The combination of a single cytoplasmic male-sterile (CMS) PET-1 and the corresponding fertility restoration (Rf) gene Rf1 is used for commercial hybrid sunflower (Helianthus annuus L., 2n = 34) seed production worldwide. A new CMS line 514A was recently developed with H. tuberosus cytoplasm. However, 33 maintainers and restorers for CMS PET-1 and 20 additional tester lines failed to restore the fertility of CMS 514A. Here, we report the discovery, characterization, and molecular mapping of a novel Rf gene for CMS 514A derived from an amphiploid (Amp H. angustifolius/P 21, 2n = 68). Progeny analysis of the male-fertile (MF) plants (2n = 35) suggested that this gene, designated Rf6, was located on a single alien chromosome. Genomic in situ hybridization (GISH) indicated that Rf6 was on a chromosome with a small segment translocation on the long arm in the MF progenies (2n = 34). Rf6 was mapped to linkage group (LG) 3 of the sunflower SSR map. Eight markers were identified to be linked to this gene, covering a distance of 10.8 cM. Two markers, ORS13 and ORS1114, were only 1.6 cM away from the gene. Severe segregation distortions were observed for both the fertility trait and the linked marker loci, suggesting the possibility of a low frequency of recombination or gamete selection in this region. This study discovered a new CMS/Rf gene system derived from wild species and provided significant insight into the genetic basis of this system. This will diversify the germplasm for sunflower breeding and facilitate understanding of the interaction between the cytoplasm and nuclear genes. PMID:23307903

  9. Citrus species and hybrids depicted by near and mid infrared spectroscopy.

    Science.gov (United States)

    Páscoa, Ricardo N M J; Moreira, Silvana; Lopes, João A; Sousa, Clara

    2018-01-31

    Citrus trees are one of the most cultivated plants around the world with high economic impact. The wide sexual compatibility among relatives gave rise to a large number of hybrids which are difficult to discriminate. This work sought to explore the ability of infrared spectroscopy to discriminate among Citrus species and/or hybrids and to contribute to the elucidation of its relatedness. Adults leaves of eighteen distinct Citrus plants were included in this work. Near and mid infrared (NIR and FTIR) leaves spectra were acquired after harvesting and a drying period of one month. Spectra were modelled by principal component analysis and partial least squares discriminant analysis. Both techniques revealed a high discrimination potential (78.5-95.9%) being the best results achieved with NIR spectroscopy and air-dried leaves (95.9%). Infrared spectroscopy was able to successfully discriminate several Citrus species and/or hybrids. Our results also contributed to enhance the insights about the studied Citrus species and/or hybrids. Despite the benefit of including additional samples, the results herein obtained clearly shown that infrared spectroscopy as a reliable technique for Citrus species and/or hybrids discrimination. This article is protected by copyright. All rights reserved.

  10. Dragee product based on sunflower

    Directory of Open Access Journals (Sweden)

    Pajin Biljana S.

    2003-01-01

    Full Text Available The sunflower kernel is rich in valuable nutritive compounds so it is suitable as a raw material for production of confectionery products. In this paper we evaluated the technological characteristics of the confectionery sunflower kernel with the aim of obtaining dragee products, and determining the final product quality and shelf life. The dragee product was obtained by panning sunflower kernel with savory powder mixture of spices in a dragee pan. The used sunflower seed has an even distribution of linear size and satisfactory dehulling characteristics. The savoury dragee product was in excellent category of sensory quality and showed stable colour and good shelf life in the period of three months.

  11. Hybridization among distantly related species: Examples from the polyploid genus Curcuma (Zingiberaceae).

    Science.gov (United States)

    Záveská, Eliška; Fér, Tomáš; Šída, Otakar; Marhold, Karol; Leong-Škorničková, Jana

    2016-07-01

    Discerning relationships among species evolved by reticulate and/or polyploid evolution is not an easy task, although it is widely discussed. The economically important genus Curcuma (ca. 120 spp.; Zingiberaceae), broadly distributed in tropical SE Asia, is a particularly interesting example of a group of palaeopolyploid origin whose evolution is driven mainly by hybridization and polyploidization. Although a phylogeny and a new infrageneric classification of Curcuma, based on commonly used molecular markers (ITS and cpDNA), have recently been proposed, significant evolutionary questions remain unresolved. We applied a multilocus approach and a combination of modern analytical methods to this genus to distinguish causes of gene tree incongruence and to identify hybrids and their parental species. Five independent regions of nuclear DNA (DCS, GAPDH, GLOBOSA3, LEAFY, ITS) and four non-coding cpDNA regions (trnL-trnF, trnT-trnL, psbA-trnH and matK), analysed as a single locus, were employed to construct a species tree and hybrid species trees using (*)BEAST and STEM-hy. Detection of hybridogenous species in the dataset was also conducted using the posterior predictive checking approach as implemented in JML. The resulting species tree outlines the relationships among major evolutionary lineages within Curcuma, which were previously unresolved or which conflicted depending upon whether they were based on ITS or cpDNA markers. Moreover, by using the additional markers in tests of plausible topologies of hybrid species trees for C. vamana, C. candida, C. roscoeana and C. myanmarensis suggested by previous molecular and morphological evidence, we found strong evidence that all the species except C. candida are of subgeneric hybrid origin. Copyright © 2016 Elsevier Inc. All rights reserved.

  12. First artificial hybrid of the eel species Anguilla australis and Anguilla anguilla

    Directory of Open Access Journals (Sweden)

    Dirks Ron P

    2011-03-01

    Full Text Available Abstract Background Studies on artificial hybridization of different Anguilla species were conducted recently, i.e. female A. australis with male A. dieffenbachii, and female A. japonica with male A. anguilla. The existence of these artificial hybrids was however not demonstrated by independent genetic methods. Two species - A. anguilla and A. australis - that are phylogenetically close but have different sexual maturation times (12-25 weeks and 6-8 weeks, respectively, were expected to produce favourable hybrids for reproduction studies. Results A modification of the protocol for the reproduction of Anguilla japonica was used to produce eight-day Anguilla australis larvae, with a success rate of 71.4%. Thus ten out of 14 females produced eggs that could be fertilized, and three batches resulted in mass hatching. Hybrid larvae from female A. australis x male A. Anguilla survived for up to seven days post fertilization (dpf. The early development of the hybrid showed typical characteristics of A. anguilla tail pigmentation at 50 hours post fertilization (hpf, indicating expression of genes derived from the father. Conclusions In this paper we describe the first production of hybrid larvae from male A. anguilla and female A. australis and their survival for up to 7 dpf. A species-specific nucleotide difference in the 18 S rDNA gene confirmed that genes from both A. australis and A. anguilla were present in the hybrids. The developmental stages of the hybrid eel embryos and larvae are described using high resolution images. Video footage also indicated a heart beat in 5-dpf larva.

  13. Origin and Electronic Features of Reactive Oxygen Species at Hybrid Zirconia-Acetylacetonate Interfaces.

    Science.gov (United States)

    Muñoz-García, Ana B; Sannino, Filomena; Vitiello, Giuseppe; Pirozzi, Domenico; Minieri, Luciana; Aronne, Antonio; Pernice, Pasquale; Pavone, Michele; D'Errico, Gerardino

    2015-10-07

    The hybrid sol-gel zirconia-acetylacetonate amorphous material (HSGZ) shows high catalytic activity in oxidative degradation reactions without light or thermal pretreatment. This peculiar HSGZ ability derives from the generation of highly reactive oxygen radical species (ROS) upon exposure to air at room conditions. We disclose the origin of such unique feature by combining EPR and DRUV measurements with first-principles calculations. The organic ligand acetylacetonate (acac) plays a pivotal role in generating and stabilizing the superoxide radical species at the HSGZ-air interfaces. Our results lead the path toward further development of HSGZ and related hybrid materials for ROS-based energy and environmental applications.

  14. Crop-weed competition between sunflower (Helianthus annuus L.) and Convolvulus arvensis L. in substitutive experiments.

    Science.gov (United States)

    Kazinczi, G; Takács, A; Horváth, J

    2006-01-01

    The main characteristics of a substitutive experiment is that the proportions of two species in the mixtures are varied while the overall density of the two species is maintained constant - a replacement series. In our experiments early competition between sunflower and field bindweed (Convolvulus arvensis) was studied in a replacement studies under glasshouse conditions. Pot experiments were set up with the following treatments: 1, sunflower 100% (6 plants pot(-1)); 2, sunflower 66.6% (4 plants pot(-1)) + C. arvensis 33.3% (2 plants pot(-1)); 3, sunflower 33.3% (2 plants pot(-1)) + C. arvensis 66.6% (4 plants pot(-1)); 4, C. arvensis 100% (6 plants pot(-1)). Sixty eight days after sowing dry weight of shoots and roots were measured and nitrogen (N), phosphorus (P) and potassium (K) content was also determined. Dry biomass production of sunflower was almost twice higher as compared to that of C. arvensis without interspecific competition. Dry weight of sunflower and C. arvensis shoots and roots for a plant continuously decreased by reducing their proportion in the mixtures. Higher biomass production of sunflower suggests, that its development is faster at the beginning of vegetation penod, therefore sunflower has better competitive ability in sunflower--C. arvensis mixtures in the early competition as compared to C. arvensis. Shoot:root ratio of plants did not change considerably in mixtures, but generally was ten times higher in sunflower plants, as compared to that of C. arvensis. Shoots generally contained macro elements at higher concentration as compared to those of roots. Total NPK content of sunflower was reduced by 53 and 82% for a pot, as its proportion decreased in the mixtures. More severe reduction in NPK content was observed in case of C. arvensis, which also proves stronger competitive ability of sunflower in the early vegetation.

  15. Hybridization and adaptive evolution of diverse Saccharomyces species for cellulosic biofuel production.

    Science.gov (United States)

    Peris, David; Moriarty, Ryan V; Alexander, William G; Baker, EmilyClare; Sylvester, Kayla; Sardi, Maria; Langdon, Quinn K; Libkind, Diego; Wang, Qi-Ming; Bai, Feng-Yan; Leducq, Jean-Baptiste; Charron, Guillaume; Landry, Christian R; Sampaio, José Paulo; Gonçalves, Paula; Hyma, Katie E; Fay, Justin C; Sato, Trey K; Hittinger, Chris Todd

    2017-01-01

    Lignocellulosic biomass is a common resource across the globe, and its fermentation offers a promising option for generating renewable liquid transportation fuels. The deconstruction of lignocellulosic biomass releases sugars that can be fermented by microbes, but these processes also produce fermentation inhibitors, such as aromatic acids and aldehydes. Several research projects have investigated lignocellulosic biomass fermentation by the baker's yeast Saccharomyces cerevisiae. Most projects have taken synthetic biological approaches or have explored naturally occurring diversity in S. cerevisiae to enhance stress tolerance, xylose consumption, or ethanol production. Despite these efforts, improved strains with new properties are needed. In other industrial processes, such as wine and beer fermentation, interspecies hybrids have combined important traits from multiple species, suggesting that interspecies hybridization may also offer potential for biofuel research. To investigate the efficacy of this approach for traits relevant to lignocellulosic biofuel production, we generated synthetic hybrids by crossing engineered xylose-fermenting strains of S. cerevisiae with wild strains from various Saccharomyces species. These interspecies hybrids retained important parental traits, such as xylose consumption and stress tolerance, while displaying intermediate kinetic parameters and, in some cases, heterosis (hybrid vigor). Next, we exposed them to adaptive evolution in ammonia fiber expansion-pretreated corn stover hydrolysate and recovered strains with improved fermentative traits. Genome sequencing showed that the genomes of these evolved synthetic hybrids underwent rearrangements, duplications, and deletions. To determine whether the genus Saccharomyces contains additional untapped potential, we screened a genetically diverse collection of more than 500 wild, non-engineered Saccharomyces isolates and uncovered a wide range of capabilities for traits relevant to

  16. HYBRIDIZATION OF SYMPATRIC PATIRIELLA SPECIES (ECHINODERMATA: ASTEROIDEA) IN NEW SOUTH WALES.

    Science.gov (United States)

    Byrne, Maria; Anderson, Marti Jane

    1994-06-01

    Three species of the asteroid genus Patiriella occur sympatrically in New South Wales and the possibility for hybridization among them was examined through a series of cross-fertilization experiments. Patiriella calcar and P. gunnii are morphologically distinct as adults but indistinguishable as larvae. Patiriella exigua is morphologically distinct in both its adult and larval morphologies. The gametes of P. calcar and P. gunnii were reciprocally compatible: laboratory crosses between these species produced viable hybrid juveniles. In crosses between female P. calcar and male P. gunnii, most of the juveniles metamorphosed with an arm number intermediate between that of the parents, whereas crosses between female P. gunnii and male P. calcar produced juveniles with an arm number more similar to the maternal phenotype. Heterospecific crosses with P. exigua resulted in low fertilization rates, and viable hybrids were not produced. This species appears capable of self-fertilization. Because hybrids between P. calcar and P. gunnii were viable, neither gametic incompatibility nor hybrid inviability appears to ensure reproductive isolation between these species. Ecological or habitat segregation and temporal separation in breeding may isolate these species in the field. The results demonstrate that if gamete surface recognition molecules are involved in fertilization of P. calcar and P. gunnii, then they are not strongly species specific, at least at the sperm concentrations used in this study. Reproductive isolation between these species has evolved despite their gametic compatibility. In contrast, P. exigua is isolated from its congeners because of gametic incompatibility and several features characteristic of its reproduction and development. The implications of these findings for reproductive isolation and speciation of Patiriella and for the evolution of reproductive isolation in free-spawning marine organisms are discussed. © 1994 The Society for the Study of

  17. Genotypic variability for antioxidant and quality parameters among tomato cultivars, hybrids, cherry tomatoes and wild species.

    Science.gov (United States)

    Kavitha, Pillakenchappa; Shivashankara, Kodthalu S; Rao, Vala K; Sadashiva, Avverahally T; Ravishankar, Kundapur V; Sathish, Gonchigar J

    2014-03-30

    Wide germplasm diversity and transferability of antioxidant parameters is the primary requirement for the development of high-antioxidant tomato cultivars. The present study was conducted to screen tomato genotypes including hybrids, varieties, cherry tomatoes, wild species, elite germplasm lines, interspecific hybrids and backcross populations for antioxidant activity and other quality parameters to select high-antioxidant lines with good total soluble solids (TSS) for further usage in crop improvement programmes. Wild species and interspecific hybrids between LA-1777 (Solanum habrochaites) and an elite genotype 15SBSB recorded very high antioxidant capacity (FRAP), DPPH radical-scavenging ability, and high phenols and flavonoids. Interspecific hybrids also recorded very high total soluble solids (TSS). Significantly higher total carotenoids, lycopene and vitamin C were observed in IIHR-249-1 with moderately higher TSS. Cherry tomato lines IIHR-2866, 2865 and 2864 recorded four to five times more β-carotene than commercial hybrids/varieties. Tomato line IIHR-249-1 can be used for improving antioxidant capacity, total carotenoids and lycopene in tomato breeding programmes. Cherry tomato lines IIHR-2866, 2865 and 2864 can be used for improving β-carotene content. LA-1777 and interspecific hybrids could be used for developing tomato lines rich in antioxidants as well as TSS. © 2013 Society of Chemical Industry.

  18. Hybrid sterility in crosses between two Brazilian sibling species of the Anopheles albitarsis complex.

    Science.gov (United States)

    Fontoura, Nathalia Giglio; Araki, Alejandra Saori; Van Der Maas Azevedo, Renata; Galardo, Allan Kardec Ribeiro; Peixoto, Alexandre Afranio; Lima, José Bento Pereira

    2014-12-04

    Complexes of cryptic species are common in several taxa and this is also the case in the Anopheles genus, a group including all known human malaria vectors. The Anopheles albitarsis complex comprises at least nine cryptic species, some of which are implicated as vectors of human malaria. Several different types of data have been generated for this species complex such as cytogenetics, alloenzymes, morphological and feeding behavioral, hybridization experiments, RAPD-PCR and RFLP and mitochondrial and nuclear markers. Studies focused on its postzygotic isolation are still somewhat rare in the literature despite their importance to understand the speciation process and the level of gene flow potentially occurring among the different sibling species. Hybridization experiments between Anopheles albitarsis s.s. and Anopheles marajoara, as well as backcrosses between hybrids and Anopheles albitarsis s.s., were performed using the induced mating technique. Results were compared to intraspecific crosses. Larva-to-adult viability and sex ratio were also assessed. Male hybrids show very low insemination rates and nearly complete sterility, apparently due to abnormalities in their reproductive organs. Evidence of partial sterility among the hybrid females was also observed. Our data indicated that Anopheles albitarsis s.s. and Anopheles marajoara show a high level of postzygotic isolation with a strong hybrid male sterility. This result is consistent with the Haldane's rule which states that in interspecific crosses the heterogametic sex is the first to be affected. However, the fact that the females are not completely sterile raises the possibility of introgression between these two siblings species.

  19. Interspecific hybridizations in ornamental flowering cherries (Prunus species)

    Science.gov (United States)

    Flowering cherries belong to the genus Prunus L., consisting primarily of species native to Asia. Despite the popularity of ornamental cherry trees in the landscape, most ornamental Prunus planted in the U.S. are derived from a limited genetic base of Japanese flowering cherry taxa. Controlled cross...

  20. Susceptibility levels of Rhododendron species and hybrids to Phytophthora ramorum

    Science.gov (United States)

    Isabelle De Dobbelaere; Kurt Heungens; Martine Maes

    2006-01-01

    Until now there has been little scientific information available about the susceptibility of different Rhododendron species and cultivars to Phytophthora ramorum. However, growers could use this knowledge as part of their control strategy. In our susceptibility screening we first optimized different inoculation methods on stem and...

  1. Prospects of eucalypt species, including interspecific hybrids from ...

    African Journals Online (AJOL)

    In Australia, there has been rapid expansion in recent years of commercial plantations of hardwood timber species, especially of Eucalyptus and Corymbia. In tropical and sub-tropical Queensland the land most likely to be readily available for this planting is in the marginal 650-1000 MAR zone where, potentially, millions of ...

  2. Interspecific differentiation and hybridization in vanilla species (Orchidaceae)

    DEFF Research Database (Denmark)

    Nielsen, Lene Rostgaard; Siegismund

    1999-01-01

    Vanilla claviculata, V. barbellata and V. dilloniana are distributed throughout the Caribbean islands and are all found in Puerto Rico. The vegetative parts of the species are similar; however, their conspicuous flowers easily distinguish them. Electrophoresis of seven polymorphic enzymes reveale...

  3. Genetic variation and relationships of seven sturgeon species and ten interspecific hybrids.

    Science.gov (United States)

    Zhang, Xiaomin; Wu, Wenhua; Li, Linmiao; Ma, Xufa; Chen, Jinping

    2013-06-28

    Sturgeon cultivation is important for both industry and aquaculture in China. To date, more than 17 species or strains have been farmed for fillets and caviar production. Crossbreeding among different sturgeon species is frequent and the F2 hybrids are fertile. However, large-scale farming can have negative impacts on wild populations i.e. escape of exotic sturgeons and must be taken into consideration. Escape of exotic sturgeons can cause severe ecological problems, including threatening native sturgeon species once the exotic varieties become established or hybridize with native individuals. However, little is known about their genetic resources and variation. Genetic diversity and introgression of seven sturgeon species were analyzed using mitochondrial DNA cytochrome oxidase subunit I (COI) and nine microsatellite markers. This study included 189 individuals from seven sturgeon species and 277 individuals from ten lineages of F2 hybrid strains. MtDNA COI sequences (632 bp long) were generated from 91 individuals across the 17 sturgeon strains and produced 23 different haplotypes. Haplotype diversity was high (h = 0.915 ± 0.015) and nucleotide diversity was low (π = 0.03680 ± 0.00153) in the seven sturgeon species and ten interspecific hybrids. Phylogenetic analyses resulted in almost identical tree topologies, and different haplotype structures were mainly related with sturgeons of different female parents. Analysis of molecular variance revealed that 81.73% of the genetic variance was due to matrilineal differences, while 9.40% resulted from strain variation. Pairwise Fst values obtained with POLYSAT software, were high among strains and ranged from 0.031 to 0.164. Admixture analysis assigned seven distinct groups and ten genotypes of admixed clusters composed of hybrid strains using STRUCTURE when assuming K = 7. The interspecific mtDNA gene tree corresponded to the expected taxonomic divisions. These relationships were also supported by the results from

  4. Triploid production from interspecific crosses of two diploid perennial Helianthus with cultivated sunflower

    Science.gov (United States)

    Wild Helianthus species are a valuable genetic source for the improvement of cultivated sunflower. We report the discovery and characterization of a unique high frequency production of triploids when cultivated sunflower was pollinated by specific accessions of diploid Helianthus nuttallii T. &. G. ...

  5. The existence of fertile hybrids of closely related model earthworm species, Eisenia andrei and E. fetida

    Science.gov (United States)

    Bigaj, Janusz; Osikowski, Artur; Hofman, Sebastian; Falniowski, Andrzej; Panz, Tomasz; Grzmil, Pawel; Vandenbulcke, Franck

    2018-01-01

    Lumbricid earthworms Eisenia andrei (Ea) and E. fetida (Ef) are simultaneous hermaphrodites with reciprocal insemination capable of self-fertilization while the existence of hybridization of these two species was still debatable. During the present investigation fertile hybrids of Ea and Ef were detected. Virgin specimens of Ea and Ef were laboratory crossed (Ea+Ef) and their progeny was doubly identified. 1 –identified by species-specific maternally derived haploid mitochondrial DNA sequences of the COI gene being either ‘a’ for worms hatched from Ea ova or ‘f’ for worms hatched from Ef ova. 2 –identified by the diploid maternal/paternal nuclear DNA sequences of 28s rRNA gene being either ‘AA’ for Ea, ‘FF’ for Ef, or AF/FA for their hybrids derived either from the ‘aA’ or ‘fF’ ova, respectively. Among offspring of Ea+Ef pairs in F1 generation there were mainly aAA and fFF earthworms resulted from the facilitated self-fertilization and some aAF hybrids from aA ova but none fFA hybrids from fF ova. In F2 generation resulting from aAF hybrids mated with aAA a new generations of aAA and aAF hybrids were noticed, while aAF hybrids mated with fFF gave fFF and both aAF and fFA hybrids. Hybrids intercrossed together produced plenty of cocoons but no hatchlings independently whether aAF+aAF or aAF+fFA were mated. These results indicated that Ea and Ef species, easy to maintain in laboratory and commonly used as convenient models in biomedicine and ecotoxicology, may also serve in studies on molecular basis of interspecific barriers and mechanisms of introgression and speciation. Hypothetically, their asymmetrical hybridization can be modified by some external factors. PMID:29370238

  6. Selection on leaf ecophysiological traits in a hybrid Helianthus species and early generation hybrids in a desert dune habitat

    NARCIS (Netherlands)

    Ludwig, F.; Rosenthal, D.R.; Johnston, J.A.; Ryan, N.; Gross, B.L.; Lexer, C.; Dudley, S.A.; Rieseberg, L.H.; Donovan, L.A.

    2004-01-01

    Leaf ecophysiological traits related to carbon gain and resource use are expected to be under strong selection in desert annuals. We used comparative and phenotypic selection approaches to investigate the importance of leaf ecophysiological traits for Helianthus anomalus, a diploid annual sunflower

  7. Deconvoluting contributions of photoexcited species in polymer-quantum dot hybrid photovoltaic materials

    Science.gov (United States)

    Couderc, Elsa; Greaney, Matthew J.; Thornbury, William; Brutchey, Richard L.; Bradforth, Stephen E.

    2015-01-01

    Ultrafast transient absorption spectroscopy is used in conjunction with spectroelectrochemistry and chemical doping experiments to study the photogeneration of charges in hybrid bulk heterojunction (BHJ) thin films composed of poly[2,6-(4,4-bis(2-ethylhexyl)-4H-cyclopenta[2,1-b:3,4-b‧]-dithiophene)-alt-4,7-(2,1,3-benzothiadiazole)] (PCPDTBT) and CdSe nanocrystals. Chemical doping experiments on hybrid and neat PCPDTBT:CdSe thin films are used to deconvolute the spectral signatures of the transient states in the near infrared. We confirm the formation and assignment of oxidized species in chemical doping experiments by comparing the spectral data to that from spectroelectrochemical measurements on hybrid and neat PCPDTBT:CdSe BHJ thin films. The deconvolution procedure allows extraction of the polaron populations in the neat polymer and hybrid thin films.

  8. EFFECTS OF ROW SPACING ON AGRONOMIC CHARACTERS OF THREE DOUBLE CROPPED SUNFLOWER HYBRIDS EFEITOS DO ESPAÇAMENTO ENTRE LINHAS NOS CARACTERES AGRONÔMICOS DE TRÊS HÍBRIDOS DE GIRASSOL CULTIVADOS NA SAFRINHA

    Directory of Open Access Journals (Sweden)

    Ana Cláudia Barneche de Oliveira

    2009-03-01

    Full Text Available

    The objective of the research was to evaluate the effects of row spacing on agronomic characteristics of three sunflower hybrids. The trial was carried out in Rio Verde, Goiás State, Brazil. The hybrids tested were Agrobel 960, BRHS 5, and Hélio 251, in four row spacing (40 cm, 50 cm, 70 cm, and 80 cm, in a population of 45.000 plants ha-1. The hybrids were planted in March 12, 2005, after bean grown in the summer season, and harvested in July 5. Achene yield and thousand weight, capitulum size, number of achenes per capitulum, and plant height were evaluated. The Agrobel 960 hybrid presented the largest achene yield and the smallest height. The larger yield of Agrobel 960 was attributed to the higher number of achenes per capitulum. The sunflower hybrids did not present significant differences for achene thousand weight and capitulum size. The 40 cm row spacing presented larger achene yield and number of achenes per capitulum. However, it did not influence the achene thousand weight, capitulum size, and plant height.

     

    KEY-WORDS: Helianthus annuus

  9. Occasional hybridization between a native and invasive Senecio species in Australia is unlikely to contribute to invasive success

    National Research Council Canada - National Science Library

    Dormontt, Eleanor E; Lowe, Andrew J; Gardner, Michael G; Prentis, Peter J

    2017-01-01

    Background Hybridization between native and invasive species can facilitate introgression of native genes that increase invasive potential by providing exotic species with pre-adapted genes suitable for new environments...

  10. Absence of postzygotic isolating mechanisms: evidence from experimental hybridization between two species of tropical sea urchins*

    OpenAIRE

    Rahman, M. Aminur; Uehara, Tsuyoshi; Arshad, Aziz; Yusoff, Fatimah Md.; Shamsudin, Mariana Nor

    2012-01-01

    Two reef margin species of tropical sea urchins, Echinometra sp. C (Ec) and Echinometra oblonga (Eo), occur sympatrically on Okinawa intertidal reefs in southern Japan. Hybridization between these species was examined through a series of cross-fertilization experiments. At limited sperm concentrations, where conspecific crosses reached near 100% fertilization, both heterospecific crosses showed high fertilization rates (81%–85%). The compatibility of the gametes demonstrated that if gamete re...

  11. The causes and evolutionary consequences of mixed singing in two hybridizing songbird species (Luscinia spp..

    Directory of Open Access Journals (Sweden)

    Jana Vokurková

    Full Text Available Bird song plays an important role in the establishment and maintenance of prezygotic reproductive barriers. When two closely related species come into secondary contact, song convergence caused by acquisition of heterospecific songs into the birds' repertoires is often observed. The proximate mechanisms responsible for such mixed singing, and its effect on the speciation process, are poorly understood. We used a combination of genetic and bioacoustic analyses to test whether mixed singing observed in the secondary contact zone of two passerine birds, the Thrush Nightingale (Luscinia luscinia and the Common Nightingale (L. megarhynchos, is caused by introgressive hybridization. We analysed song recordings of both species from allopatric and sympatric populations together with genotype data from one mitochondrial and seven nuclear loci. Semi-automated comparisons of our recordings with an extensive catalogue of Common Nightingale song types confirmed that most of the analysed sympatric Thrush Nightingale males were 'mixed singers' that use heterospecific song types in their repertoires. None of these 'mixed singers' possessed any alleles introgressed from the Common Nightingale, suggesting that they were not backcross hybrids. We also analysed songs of five individuals with intermediate phenotype, which were identified as F1 hybrids between the Thrush Nightingale female and the Common Nightingale male by genetic analysis. Songs of three of these hybrids corresponded to the paternal species (Common Nightingale but the remaining two sung a mixed song. Our results suggest that although hybridization might increase the tendency for learning songs from both parental species, interspecific cultural transmission is the major proximate mechanism explaining the occurrence of mixed singers among the sympatric Thrush Nightingales. We also provide evidence that mixed singing does not substantially increase the rate of interspecific hybridization and discuss

  12. Evaluation of Alnus species and hybrids. [For biomass energy production

    Energy Technology Data Exchange (ETDEWEB)

    Hall, R.B. (Iowa State Univ., Ames, IA (US). Dept. of Forestry); Burgess, D. (Petawawa National Forestry Inst., Chalk River, Ontario (CA))

    1990-01-01

    Trials of a common set of seed lots representing 39 parents and five species of Alnus have been started in four countries: Belgium, Canada, the UK, and the US. Initial results indicate that cold hardiness is a problem in using A. acuminata but that sufficiently hardy A. rubra sources are available. A. glutinosa had the best growth in the nursery, and A. cordata had the best survival under severe moisture-stress conditions. A summary also is given of a workshop on alder improvement that further demonstrates the potential for developing the genus for biomass energy production. (author).

  13. Photonic and Phononic Entanglement with Hybrid Species Ion Chains

    Science.gov (United States)

    Crocker, Clayton; Lichtman, Martin; Sosnova, Ksenia; Nguyen, Tuan; Carter, Allison; Inlek, Volkan; Ruth, Hanna; Monroe, Christopher

    2017-04-01

    Trapped atomic ions represent a leading platform for quantum information networks due to their long coherence times and diverse set of entangling operations. External fields can drive strong local entangling interactions via phonons, and remote qubits can be entangled via emitted photons. Unfortunately, resonant light from the photonic entanglement process can disrupt nearby memory qubits. We resolve this crosstalk by introducing a separate atomic species to the trap for use as a photonic entanglement qubit. We report successful demonstration of both entangling gates between the mixed species qubit pair through their collective motion, and entanglement between our remote entanglement qubit and emitted visible photons. We additionally report our progress on a new trapping apparatus that was implemented to improve these operations to a level required for scaling up the system size. This work is supported by the ARO with funding from the IARPA LogiQ program, the AFOSR, the ARO MURI on Modular Quantum Circuits, the AFOSR MURI on Quantum Transduction, and the ARL Center for Distributed Quantum Information.

  14. Microarray-based whole-genome hybridization as a tool for determining procaryotic species relatedness

    Energy Technology Data Exchange (ETDEWEB)

    Wu, L.; Liu, X.; Fields, M.W.; Thompson, D.K.; Bagwell, C.E.; Tiedje, J. M.; Hazen, T.C.; Zhou, J.

    2008-01-15

    The definition and delineation of microbial species are of great importance and challenge due to the extent of evolution and diversity. Whole-genome DNA-DNA hybridization is the cornerstone for defining procaryotic species relatedness, but obtaining pairwise DNA-DNA reassociation values for a comprehensive phylogenetic analysis of procaryotes is tedious and time consuming. A previously described microarray format containing whole-genomic DNA (the community genome array or CGA) was rigorously evaluated as a high-throughput alternative to the traditional DNA-DNA reassociation approach for delineating procaryotic species relationships. DNA similarities for multiple bacterial strains obtained with the CGA-based hybridization were comparable to those obtained with various traditional whole-genome hybridization methods (r=0.87, P<0.01). Significant linear relationships were also observed between the CGA-based genome similarities and those derived from small subunit (SSU) rRNA gene sequences (r=0.79, P<0.0001), gyrB sequences (r=0.95, P<0.0001) or REP- and BOX-PCR fingerprinting profiles (r=0.82, P<0.0001). The CGA hybridization-revealed species relationships in several representative genera, including Pseudomonas, Azoarcus and Shewanella, were largely congruent with previous classifications based on various conventional whole-genome DNA-DNA reassociation, SSU rRNA and/or gyrB analyses. These results suggest that CGA-based DNA-DNA hybridization could serve as a powerful, high-throughput format for determining species relatedness among microorganisms.

  15. Gene expression disruptions of organism versus organ in Drosophila species hybrids.

    Directory of Open Access Journals (Sweden)

    Daniel J Catron

    2008-08-01

    Full Text Available Hybrid dysfunctions, such as sterility, may result in part from disruptions in the regulation of gene expression. Studies of hybrids within the Drosophila simulans clade have reported genes expressed above or below the expression observed in their parent species, and such misexpression is associated with male sterility in multigenerational backcross hybrids. However, these studies often examined whole bodies rather than testes or had limited replication using less-sensitive but global techniques. Here, we use a new RNA isolation technique to re-examine hybrid gene expression disruptions in both testes and whole bodies from single Drosophila males by real-time quantitative RT-PCR. We find two early-spermatogenesis transcripts are underexpressed in hybrid whole-bodies but not in assays of testes alone, while two late-spermatogenesis transcripts seem to be underexpressed in both whole-bodies and testes alone. Although the number of transcripts surveyed is limited, these results provide some support for a previous hypothesis that the spermatogenesis pathway in these sterile hybrids may be disrupted sometime after the expression of the early meiotic arrest genes.

  16. Plant Regeneration and Somatic Embryogenesis from Immature Embryos Derived through Interspecific Hybridization among Different Carica Species

    Directory of Open Access Journals (Sweden)

    Latifah Amin

    2012-12-01

    Full Text Available Plant regeneration and somatic embryogenesis through interspecific hybridization among different Carica species were studied for the development of a papaya ringspot virus-resistant variety. The maximum fruit sets were recorded from the cross of the native variety C. papaya cv. Shahi with the wild species C. cauliflora. The highest hybrid embryos were recorded at 90 days after pollination and the embryos were aborted at 150 days after pollination. The immature hybrid embryos were used for plant regeneration and somatic embryogenesis. The 90-day-old hybrid embryos from the cross of C. papaya cv. Shahi × C. cauliflora showed the highest percentage of germination, as well as plant regeneration on growth regulators free culture medium after 7 days pre-incubation on half-strength MS medium supplemented with 0.2 mg/L BAP, 0.5 mg/L NAA and 60 g/L sucrose. The 90-day-old hybrid embryos from the cross of C. papaya cv. Shahi × C. cauliflora produced maximum callus, as well as somatic embryos when cultured on half-strength MS medium containing 5 mg/L 2,4-D, 100 mg/L glutamine, 100 mg/L casein hydrolysate and 60 g/L sucrose. The somatic embryos were transferred into half-strength MS medium containing 0.5 mg/L BAP and 0.2 mg/L NAA and 60 g/L sucrose for maturation. The highest number of regenerated plants per hybrid embryo (10.33 was recorded from the cross of C. papaya cv. Shahi × C. cauliflora. Isoenzyme and dendrogram cluster analysis using UPGMA of the regenerated F1 plantlets confirmed the presence of the hybrid plantlets.

  17. Plant regeneration and somatic embryogenesis from immature embryos derived through interspecific hybridization among different Carica species.

    Science.gov (United States)

    Azad, Md Abul Kalam; Rabbani, Md Golam; Amin, Latifah

    2012-12-12

    Plant regeneration and somatic embryogenesis through interspecific hybridization among different Carica species were studied for the development of a papaya ringspot virus-resistant variety. The maximum fruit sets were recorded from the cross of the native variety C. papaya cv. Shahi with the wild species C. cauliflora. The highest hybrid embryos were recorded at 90 days after pollination and the embryos were aborted at 150 days after pollination. The immature hybrid embryos were used for plant regeneration and somatic embryogenesis. The 90-day-old hybrid embryos from the cross of C. papaya cv. Shahi × C. cauliflora showed the highest percentage of germination, as well as plant regeneration on growth regulators free culture medium after 7 days pre-incubation on half-strength MS medium supplemented with 0.2 mg/L BAP, 0.5 mg/L NAA and 60 g/L sucrose. The 90-day-old hybrid embryos from the cross of C. papaya cv. Shahi × C. cauliflora produced maximum callus, as well as somatic embryos when cultured on half-strength MS medium containing 5 mg/L 2,4-D, 100 mg/L glutamine, 100 mg/L casein hydrolysate and 60 g/L sucrose. The somatic embryos were transferred into half-strength MS medium containing 0.5 mg/L BAP and 0.2 mg/L NAA and 60 g/L sucrose for maturation. The highest number of regenerated plants per hybrid embryo (10.33) was recorded from the cross of C. papaya cv. Shahi × C. cauliflora. Isoenzyme and dendrogram cluster analysis using UPGMA of the regenerated F(1) plantlets confirmed the presence of the hybrid plantlets.

  18. A new Epichloe species with interspecific hybrid origins from Poa pratensis ssp. pratensis in Liyang, China.

    Science.gov (United States)

    Yan, Kang; Yanling, Ji; Kunran, Zhu; Hui, Wang; Huimin, Miao; Zhiwei, Wang

    2011-01-01

    We describe a new Epichloë species found in symbiosis with Poa pratensis ssp. pratensis in Liyang, China. Stromata characteristic of Epichloë spp. were present on some of the reproductive tillers of individual host grasses. Only three of the 98 stromata observed on field plants became orange and produced perithecia. Phylogenetic analyses based on sequences of tubB and tefA indicated that this Epichloë sp. was an interspecific hybrid related to both E. yangzii and members in the E. typhina complex clade (ETC). Allele-1 of tefA and tubB grouped in the E. bromicola/E. yangzii clade; allele-2 of these two genes clustered in a distinct subclade in the ETC. This is the first report of an Epichloë species that has interspecific hybrid origins. We propose the name Epichloë liyangensis Z. Wang, Y. Kang et H. Miao, sp. nov. for this species.

  19. HOW DISCRETE ARE OAK SPECIES? INSIGHTS FROM A HYBRID ZONE BETWEEN QUERCUS GRISEA AND QUERCUS GAMBELII.

    Science.gov (United States)

    Howard, Daniel J; Preszler, Ralph W; Williams, Joseph; Fenchel, Sandra; Boecklen, William J

    1997-06-01

    The white oaks Quercus gambelii and Q. grisea overlap in distribution in New Mexico and Arizona. Within the region of overlap, there are numerous instances of contact between the two taxa. In some areas of contact morphologically, intermediate trees are common, whereas in others, morphologically intermediate trees are rare or absent. We describe a set of RAPD markers that distinguish between the two species and use these markers to examine patterns of gene exchange in an area of contact in the San Mateo Mountains of New Mexico. The markers are highly coincident with morphology and confirm that hybridization between the two species takes place. Despite the occurrence of hybrids, both species remain distinct, even in areas of sympatry, and marker exchange appears to be limited. © 1997 The Society for the Study of Evolution.

  20. Integrated management of sunflower necrosis disease

    OpenAIRE

    Shirshikar S.P.

    2008-01-01

    Sunflower necrosis disease (SND) is a new threat for sunflower cultivation in India. The disease was observed during 1997 in Karnataka, a major sunflower growing state of India. Later, its occurrence was reported from almost all sunflower growing states of India, posing threat to sunflower cultivation. Presently no reliable resistant sources are available. The disease being viral in nature is very much difficult to combat by single approach. At Oilseeds Research Station, Latur (M.S.), India, ...

  1. [Study of Chloroplast DNA Polymorphism in the Sunflower (Helianthus L.)].

    Science.gov (United States)

    Markina, N V; Usatov, A V; Logacheva, M D; Azarin, K V; Gorbachenko, C F; Kornienko, I V; Gavrilova, V A; Tihobaeva, V E

    2015-08-01

    The polymorphism of microsatellite loci of chloroplast genome in six Helianthus species and 46 lines of cultivated sunflower H. annuus (17 CMS lines and 29 Rf-lines) were studied. The differences between species are confined to four SSR loci. Within cultivated forms of the sunflower H. annuus, the polymorphism is absent. A comparative analysis was performed on sequences of the cpDNA inbred line 3629, line 398941 of the wild sunflower, and the American line HA383 H. annuus. As a result, 52 polymorphic loci represented by 27 SSR and 25 SNP were found; they can be used for genotyping of H. annuus samples, including cultural varieties: twelve polymorphic positions, of which eight are SSR and four are SNP.

  2. Interspecific hybridization in Lily (Lilium): Taxonomic and commercial aspects of using species hybrids in breeding

    NARCIS (Netherlands)

    Lim, K.B.; Barba Gonzalez, R.; Shujun Zhou,; Ramanna, M.S.; Tuyl, van J.M.

    2007-01-01

    With the main goal of generating new groups of lilies, that combine agronomic characteristics of major importance, a large number of crosses were performed among the three most important groups of lilies (Lilium), viz., Asiatic, Longiflorum and Oriental; and to some species, to produce F1

  3. Frankincense Revisited, Part II: Volatiles in Rare Boswellia Species and Hybrids.

    Science.gov (United States)

    Niebler, Johannes; Eslamieh, Jason; Buettner, Andrea

    2016-05-01

    In this second part of the investigation of volatiles and semivolatiles in Boswellia gum resins, an additional five less common species were analyzed by (SPME-)GC/MS, namely B. ameero, B. elongata, B. neglecta, B. popoviana, and B. rivae. Moreover, the results of hybridization experiments are reported in combination with the volatile composition of their gum resins. Our study shows that B. sacra benefits from an intraspecific cross-pollination, as the resulting hybrid B. sacra var. supersacra has a far higher seed germination rate and viability. © 2016 Verlag Helvetica Chimica Acta AG, Zürich.

  4. Signaling through reactive oxygen and nitrogen species is differentially modulated in sunflower seedling root and cotyledon in response to various nitric oxide donors and scavengers.

    Science.gov (United States)

    Singh, Neha; Bhatla, Satish C

    2017-09-02

    Sodium nitroprusside (SNP), diethylenetriamine NONOate (DETA), S-nitroso-n-acetyl-D,L- penicillamine (SNAP), and 4-(p-methoxyphenyl)-1,3,2- Oxathiazolylium-5-olate (CAY) exhibit differential NO releasing ability in aqueous solution and hemoglobin is a more efficient NO quencher than cPTIO in solution. DETA releases 16% more NO compared with SNP in solution. Various NO donors (SNP, DETA, SNAP, and CAY) also bring about a differential but concentration-dependent increase in endogenous NO in seedling cotyledons and roots. Two-day old, dark-grown seedling roots exhibit 95%, 77%, 59% and 45% increase in NO content in presence of each of 500 µM of DETA, SNAP, CAY and SNP, respectively, relative to control. NO accumulation in the tissue system as a response to NO donors is reflected in terms of corresponding peroxynitrite accumulation. Release of cyanide and free iron as byproducts of SNP dissociation in solution limits its usefulness as an NO donor. SNP leads to profuse ROS generation in sunflower seedling roots. Light is not a pre-requisite for NO generation from SNP. Present work also demonstrates the usefulness of hemoglobin over cPTIO as NO scavenger. Hemoglobin brings about increasing NO quenching with its increasing concentration from 2.5 to 10 µM. Greater sensitivity of the root system to the NO donor/scavenger treatments is evident, it being in direct contact with the molecules in the incubation/ growth medium. This differential effect does not seem to be significantly transmitted to the cotyledons (long-distance signaling).

  5. The Population Genomics of Sunflowers and Genomic Determinants of Protein Evolution Revealed by RNAseq

    Directory of Open Access Journals (Sweden)

    Loren H. Rieseberg

    2012-10-01

    Full Text Available Few studies have investigated the causes of evolutionary rate variation among plant nuclear genes, especially in recently diverged species still capable of hybridizing in the wild. The recent advent of Next Generation Sequencing (NGS permits investigation of genome wide rates of protein evolution and the role of selection in generating and maintaining divergence. Here, we use individual whole-transcriptome sequencing (RNAseq to refine our understanding of the population genomics of wild species of sunflowers (Helianthus spp. and the factors that affect rates of protein evolution. We aligned 35 GB of transcriptome sequencing data and identified 433,257 polymorphic sites (SNPs in a reference transcriptome comprising 16,312 genes. Using SNP markers, we identified strong population clustering largely corresponding to the three species analyzed here (Helianthus annuus, H. petiolaris, H. debilis, with one distinct early generation hybrid. Then, we calculated the proportions of adaptive substitution fixed by selection (alpha and identified gene ontology categories with elevated values of alpha. The “response to biotic stimulus” category had the highest mean alpha across the three interspecific comparisons, implying that natural selection imposed by other organisms plays an important role in driving protein evolution in wild sunflowers. Finally, we examined the relationship between protein evolution (dN/dS ratio and several genomic factors predicted to co-vary with protein evolution (gene expression level, divergence and specificity, genetic divergence [FST], and nucleotide diversity pi. We find that variation in rates of protein divergence was correlated with gene expression level and specificity, consistent with results from a broad range of taxa and timescales. This would in turn imply that these factors govern protein evolution both at a microevolutionary and macroevolutionary timescale. Our results contribute to a general understanding of the

  6. [Study on the quantitative and qualitative composition of moulds colonizing sunflower seeds (Helianthus annus L.)].

    Science.gov (United States)

    Janda, Katarzyna; Wolska, Jolanta; Debia, Kamila

    2015-01-01

    The aim of study was to estimate the qualitative and quantitative composition of moulds colonizing sunflower seeds on RBCA, YpSs, DG18 media at 25, 37, and 45°C. Twenty samples of sunflower seeds (not roasted and not salted) were used for the analysis. The highest number of moulds were xerophilic species isolated on DG18 at 25°C (33), followed by mesophilic species (29) on RBCA medium at 25°C, and mesophilic (22) and thermophilic species (10) on YpSs medium at 37, and 45°C, respectively. Eurotium herbariorum was isolated from all samples. A total of 287 strains belonging to 52 mould species were isolated from sunflower seeds. The study revealed new species not previously isolated from sunflower seeds mycobiota.

  7. Ocean warming, a rapid distributional shift, and the hybridization of a coastal fish species.

    Science.gov (United States)

    Potts, Warren M; Henriques, Romina; Santos, Carmen V; Munnik, Kate; Ansorge, Isabelle; Dufois, Francois; Booth, Anthony J; Kirchner, Carola; Sauer, Warwick H H; Shaw, Paul W

    2014-09-01

    Despite increasing awareness of large-scale climate-driven distribution shifts in the marine environment, no study has linked rapid ocean warming to a shift in distribution and consequent hybridization of a marine fish species. This study describes rapid warming (0.8 °C per decade) in the coastal waters of the Angola-Benguela Frontal Zone over the last three decades and a concomitant shift by a temperature sensitive coastal fish species (Argyrosomus coronus) southward from Angola into Namibia. In this context, rapid shifts in distribution across Economic Exclusive Zones will complicate the management of fishes, particularly when there is a lack of congruence in the fisheries policy between nations. Evidence for recent hybridization between A. coronus and a congener, A. inodorus, indicate that the rapid shift in distribution of A. coronus has placed adults of the two species in contact during their spawning events. Ocean warming may therefore revert established species isolation mechanisms and alter the evolutionary history of fishes. While the consequences of the hybridization on the production of the resource remain unclear, this will most likely introduce additional layers of complexity to their management. © 2014 John Wiley & Sons Ltd.

  8. Detection of recent hybridization between sympatric Chilean Puya species (Bromeliaceae) using AFLP markers and reconstruction of complex relationships.

    Science.gov (United States)

    Schulte, Katharina; Silvestro, Daniele; Kiehlmann, Elke; Vesely, Sanja; Novoa, Patricio; Zizka, Georg

    2010-12-01

    The Chilean Puya species constitute a monophyletic group, co-occurring in different species combinations within the country and displaying a remarkable morphological variability. Here, we studied the importance of recent hybridization and introgression in the group and reconstructed the complex inter- and intraspecific relationships. Amplified fragment length polymorphism (AFLP) analysis, including 109 accessions of all Chilean Puya species and four putative hybrids, yielded 984 characters. Three main genetic groups were revealed, with the chilensis group (P. chilensis, P. gilmartiniae, P. boliviensis) diverging first, and the alpestris (P. alpestris, P. berteroniana) and coerulea group (P. venusta, P. coerulea) forming sister groups. STRUCTURE analyses confirmed a hybrid origin of morphologically intermediate individuals, and detected several additional hybrids. Hybrids were found between the chilensis and alpestris group, and between the alpestris and coerulea group. Exclusion of hybrids improved phylogenetic reconstructions. The study demonstrates that the detection of hybrids within Bromeliaceae can be difficult based on morphological characters alone and that efficient reproductive barriers may only slowly establish, leading to hybridization between closely related sympatric species. The importance of hybridization for the rapid diversification of Puya is discussed. Copyright © 2010 Elsevier Inc. All rights reserved.

  9. Maternal and paternal lineages in cross-breeding bovine species. Has wisent a hybrid origin?

    Science.gov (United States)

    Verkaar, Edward L C; Nijman, Isaäc J; Beeke, Maurice; Hanekamp, Eline; Lenstra, Johannes A

    2004-07-01

    The tribe Bovini comprises cattle and cattle-like species. Reconstructions of their phylogeny have so far been incomplete and have yielded conflicting conclusions about the relationship of American bison and wisent (European bison). We have compared the sequences of three mitochondrial and two Y-chromosomal DNA segments. Mitochondrial DNA indicates that four distinct maternal lineages diverged after an early split-off of the buffalo species, leading to (1) taurine cattle and zebu, (2) wisent, (3) American bison and yak, and (4) banteng, gaur, and gayal, respectively. At a higher level, lineages (1) and (2) and lineages (3) and (4) are probably associated. In contrast, Y-chromosomal sequences indicate a close association of American and European bison, which is in agreement with their morphological similarity, complete fertility of hybrid offspring, and amplified fragment length polymorphism (AFLP) fingerprints of nuclear DNA. One explanation for the anomalous divergence of the mitochondrial DNA from the two bison species is lineage sorting, which implies that two distinct mitochondrial lineages coexisted in the bison-yak branch until the recent divergence of American bison and wisent. Alternatively, the wisent may have emerged by species hybridization initiated by introgression of bison bulls in another ancestral species. This "transpatric" mode of species formation would be consistent with the recent appearance of the wisent in the fossil record without clearly identifiable ancestors.

  10. Electric Characteristics of Hybrid Polymer Membranes Composed of Two Lipid Species

    Science.gov (United States)

    Oohira, Koji; Toko, Kiyoshi; Akiyama, Hideyuki; Yoshihara, Hiroshi; Yamafuji, Kaoru

    1995-09-01

    Electric characteristics of hybrid polymer membranes composed of two lipid species were studied, where one lipid species is positively charged in aqueous solution and the other is negatively charged. As a result, it was found that the hybrid membranes responded to taste substances in different ways according to the molar mixing ratio of these two kinds of lipids, and also showed different response characteristics from those of the single-lipid membranes. The membranes with the mixing ratio around 50% exhibited the largest responses to HCl (sourness) and monosodium glutamate (umami). Moreover, good quantitative agreements with the observed data on the response electric potential were obtained using a theory describing both the changes in surface electric potential and surface charge density with taste substances.

  11. Evaluation and Identification of Alternaria leaf spot resistant sunflower genotypes

    OpenAIRE

    C. Gopalakrishnan, N.Manivannan, P.Vindhiyavarman and K.Thiyagarajan

    2010-01-01

    All India coordinated sunflower entries belonging to advance hybrid trial were screened initially by infector rowtechnique under field conditions followed by green house conditions by artificial inoculation during 2007 and2008 for Alternaria leaf blight resistance. The study indicated that field screening alone is not dependable forassessing the disease resistance, especially when the disease pressure is less because of chances of diseaseescape. The present study clearly shows that green hous...

  12. Whole-mount in situ hybridization of sectioned tissues of species hybrids to detect cis-regulatory changes in gene expression pattern.

    Science.gov (United States)

    Futahashi, Ryo

    2011-01-01

    To distinguish whether differences in gene expression between species or between individuals of the same species are caused by cis-regulatory changes or by distribution differences in trans-regulatory proteins, comparison of species-specific mRNA expression in an F1 hybrid by whole-mount in situ hybridization is a rarely used yet very powerful tool. If asymmetric expression pattern is observed for the two alleles, this implies a cis-regulatory divergence of this gene. Alternatively, if symmetric expression pattern is observed for both alleles, the change in expression of this gene is probably caused by changes in the distribution of trans-regulatory proteins. In this chapter, I describe how to prepare RNA probes, tissue samples and how to detect mRNA expression pattern using in situ hybridization. Although I choose to present here the detection of yellow-related gene (YRG) expression pattern in the larval epidermis of swallowtail butterflies, this protocol can be adapted to other species and tissues. YRG mRNA expression is correlated with interspecific differences of yellow and green larval color pattern such as V-shaped markings in swallowtail butterflies. F1 hybrids show an intermediate color pattern between parental species. In this case, both species-specific YRG mRNA showed a similar expression pattern in F1 hybrids, suggesting that the change in expression of YRG is mainly caused by changes in the distribution of trans-regulatory proteins.

  13. Biological and genetic aspects of experimental hybrids from species of the Phyllosoma complex (Hemiptera: Reduviidae: Triatominae)

    OpenAIRE

    José Alejandro Martínez-Ibarra; Luz Verónica Ventura-Rodríguez; Karla Meillon-Isais; Héctor Barajas-Martínez; Ricardo Alejandre-Aguilar; Patricia Lupercio-Coronel; Gonzalo Rocha-Chávez; Benjamín Nogueda-Torres

    2008-01-01

    The present work is a thorough investigation of the degree of reproductive isolation between Meccus mazzottii and Meccus longipennis, Meccus picturatus, Meccus pallidipennis and Meccus bassolsae, as well as between M. longipennis and M. picturatus. We examined fertility and segregation of morphological characteristics in two generations of hybrids derived from crosses between these species. The percentage of pairs with (fertile) offspring was highest in the set of crosses between M. longipenn...

  14. Detection and Identification of Entamoeba Species in Stool Samples by a Reverse Line Hybridization Assay

    OpenAIRE

    Verweij, Jaco J.; Laeijendecker, Daphne; Eric A T Brienen; van Lieshout, Lisette; Polderman, Anton M.

    2003-01-01

    Classically, detection of Entamoeba histolytica is performed by microscopic examination for characteristic cysts and/or trophozoites in fecal preparations. Differentiation of E. histolytica cysts and those of nonpathogenic amoebic species is made on the basis of the appearance and the size of the cysts. However, by classical means objective tools for confirmation and quality control do not exist. Therefore, a reverse line blot hybridization assay was developed to detect a variety of Entamoeba...

  15. Species-specific heterochromatin prevents mitotic chromosome segregation to cause hybrid lethality in Drosophila.

    Directory of Open Access Journals (Sweden)

    Patrick M Ferree

    2009-10-01

    Full Text Available Postzygotic reproductive barriers such as sterility and lethality of hybrids are important for establishing and maintaining reproductive isolation between species. Identifying the causal loci and discerning how they interfere with the development of hybrids is essential for understanding how hybrid incompatibilities (HIs evolve, but little is known about the mechanisms of how HI genes cause hybrid dysfunctions. A previously discovered Drosophila melanogaster locus called Zhr causes lethality in F1 daughters from crosses between Drosophila simulans females and D. melanogaster males. Zhr maps to a heterochromatic region of the D. melanogaster X that contains 359-bp satellite repeats, suggesting either that Zhr is a rare protein-coding gene embedded within heterochromatin, or is a locus consisting of the noncoding repetitive DNA that forms heterochromatin. The latter possibility raises the question of how heterochromatic DNA can induce lethality in hybrids. Here we show that hybrid females die because of widespread mitotic defects induced by lagging chromatin at the time during early embryogenesis when heterochromatin is first established. The lagging chromatin is confined solely to the paternally inherited D. melanogaster X chromatids, and consists predominantly of DNA from the 359-bp satellite block. We further found that a rearranged X chromosome carrying a deletion of the entire 359-bp satellite block segregated normally, while a translocation of the 359-bp satellite block to the Y chromosome resulted in defective Y segregation in males, strongly suggesting that the 359-bp satellite block specifically and directly inhibits chromatid separation. In hybrids produced from wild-type parents, the 359-bp satellite block was highly stretched and abnormally enriched with Topoisomerase II throughout mitosis. The 359-bp satellite block is not present in D. simulans, suggesting that lethality is caused by the absence or divergence of factors in the D

  16. On the origin of asexual species by means of hybridization and drift.

    Science.gov (United States)

    Hartfield, Matthew

    2016-07-01

    Several species of asexuals appear to have existed for millions of years. This is despite the prevalent view that natural selection is weakened without gene exchange, which should cause these organisms to rapidly go extinct. In theory, one can identify evolutionary long-lived asexuals from their allelic sequence divergence, also known as the 'Meselson effect', which leads to elevated within-individual diversity. Yet evidence that this phenomenon exists is mixed. Furthermore, several confounding factors can lead to similar outcomes, including the formation of asexual species by hybridization. Disentangling these factors has proved to be tricky, but Ament-Velásquez et al. (2016) have provided an elegant solution in this issue of Molecular Ecology. They studied transcriptomes and mitochondrial DNA from the Lineus genus of nemertean worms, which contains both sexual and asexual types, to first show that the asexual L. pseudolactus is a hybrid between a sexual and an asexual species. After isolating out diversity arising from this hybridization, they find subsequent evidence for the Meselson effect. This study sets a new standard for differentiating between the complex causes and consequences of asexuality. © 2016 John Wiley & Sons Ltd.

  17. Natural Rubber Quantification in Sunflower Using an Automated Solvent Extractor

    Science.gov (United States)

    Leaves of sunflower (Helianthus annuus) produce a small amount of low molecular weight natural rubber (NR) and this species has potential as a rubber-producing crop plant. Quantifying NR in plant tissue has traditionally been accomplished using Soxhlet or gravimetric methodologies. Accelerated solve...

  18. An introduced and a native vertebrate hybridize to form a genetic bridge to a second native species

    Science.gov (United States)

    McDonald, D.B.; Parchman, T.L.; Bower, M.R.; Hubert, W.A.; Rahel, F.J.

    2008-01-01

    The genetic impacts of hybridization between native and introduced species are of considerable conservation concern, while the possibility of reticulate evolution affects our basic understanding of how species arise and shapes how we use genetic data to understand evolutionary diversification. By using mitochondrial NADH dehydrogenase subunit 2 (ND2) sequences and 467 amplified fragment-length polymorphism nuclear DNA markers, we show that the introduced white sucker (Catostomus commersoni) has hybridized with two species native to the Colorado River Basin - the flannelmouth sucker (Catostomus latipinnis) and the bluehead sucker (Catostomus discobolus). Hybrids between the flannelmouth sucker and white sucker have facilitated introgression between the two native species, previously isolated by reproductive barriers, such that individuals exist with contributions from all three genomes. Most hybrids had the mitochondrial haplotype of the introduced white sucker, emphasizing its pivotal role in this three-way hybridization. Our findings highlight how introduced species can threaten the genetic integrity of not only one species but also multiple previously reproductively isolated species. Furthermore, this complex three-way reticulate (as opposed to strictly bifurcating) evolution suggests that seeking examples in other vertebrate systems might be productive. Although the present study involved an introduced species, similar patterns of hybridization could result from natural processes, including stream capture or geological formations (e.g., the Bering land bridge). ?? 2008 by The National Academy of Sciences of the USA.

  19. An introduced and a native vertebrate hybridize to form a genetic bridge to a second native species.

    Science.gov (United States)

    McDonald, David B; Parchman, Thomas L; Bower, Michael R; Hubert, Wayne A; Rahel, Frank J

    2008-08-05

    The genetic impacts of hybridization between native and introduced species are of considerable conservation concern, while the possibility of reticulate evolution affects our basic understanding of how species arise and shapes how we use genetic data to understand evolutionary diversification. By using mitochondrial NADH dehydrogenase subunit 2 (ND2) sequences and 467 amplified fragment-length polymorphism nuclear DNA markers, we show that the introduced white sucker (Catostomus commersoni) has hybridized with two species native to the Colorado River Basin--the flannelmouth sucker (Catostomus latipinnis) and the bluehead sucker (Catostomus discobolus). Hybrids between the flannelmouth sucker and white sucker have facilitated introgression between the two native species, previously isolated by reproductive barriers, such that individuals exist with contributions from all three genomes. Most hybrids had the mitochondrial haplotype of the introduced white sucker, emphasizing its pivotal role in this three-way hybridization. Our findings highlight how introduced species can threaten the genetic integrity of not only one species but also multiple previously reproductively isolated species. Furthermore, this complex three-way reticulate (as opposed to strictly bifurcating) evolution suggests that seeking examples in other vertebrate systems might be productive. Although the present study involved an introduced species, similar patterns of hybridization could result from natural processes, including stream capture or geological formations (e.g., the Bering land bridge).

  20. Unidirectional hybridization at a species' range boundary: implications for habitat tracking

    DEFF Research Database (Denmark)

    Beatty, Gemma, E.; Philipp, Marianne; Provan, Jim

    2010-01-01

     Genetic analysis of samples from Greenland and Canada was carried out using a combination of nuclear and chloroplast single nucleotide polymorphisms (SNPs). Results Analysis of nuclear SNPs confirmed hybridization in populations of morphologically intermediate individuals, as well as revealing the existence....... This could compromise the ability of species to respond to climate change via habitat tracking, although the final outcome of these processes may ultimately depend on the rate of global climate change and its effect on the species' distributions....

  1. Immediate Genetic and Epigenetic Changes in F1 Hybrids Parented by Species with Divergent Genomes in the Rice Genus (Oryza).

    Science.gov (United States)

    Wu, Ying; Sun, Yue; Shen, Kun; Sun, Shuai; Wang, Jie; Jiang, Tingting; Cao, Shuai; Josiah, Samuel Manthi; Pang, Jinsong; Lin, Xiuyun; Liu, Bao

    2015-01-01

    Inter-specific hybridization occurs frequently in higher plants, and represents a driving force of evolution and speciation. Inter-specific hybridization often induces genetic and epigenetic instabilities in the resultant homoploid hybrids or allopolyploids, a phenomenon known as genome shock. Although genetic and epigenetic consequences of hybridizations between rice subspecies (e.g., japonica and indica) and closely related species sharing the same AA genome have been extensively investigated, those of inter-specific hybridizations between more remote species with different genomes in the rice genus, Oryza, remain largely unknown. We investigated the immediate chromosomal and molecular genetic/epigenetic instability of three triploid F1 hybrids produced by inter-specific crossing between species with divergent genomes of Oryza by genomic in situ hybridization (GISH) and molecular marker analysis. Transcriptional and transpositional activity of several transposable elements (TEs) and methylation stability of their flanking regions were also assessed. We made the following principle findings: (i) all three triploid hybrids are stable in both chromosome number and gross structure; (ii) stochastic changes in both DNA sequence and methylation occurred in individual plants of all three triploid hybrids, but in general methylation changes occurred at lower frequencies than genetic changes; (iii) alteration in DNA methylation occurred to a greater extent in genomic loci flanking potentially active TEs than in randomly sampled loci; (iv) transcriptional activation of several TEs commonly occurred in all three hybrids but transpositional events were detected in a genetic context-dependent manner. Artificially constructed inter-specific hybrids of remotely related species with divergent genomes in genus Oryza are chromosomally stable but show immediate and highly stochastic genetic and epigenetic instabilities at the molecular level. These novel hybrids might provide a rich

  2. Development, characterization and experimental validation of a cultivated sunflower (Helianthus annuus L.) gene expression oligonucleotide microarray.

    Science.gov (United States)

    Fernandez, Paula; Soria, Marcelo; Blesa, David; DiRienzo, Julio; Moschen, Sebastian; Rivarola, Maximo; Clavijo, Bernardo Jose; Gonzalez, Sergio; Peluffo, Lucila; Príncipi, Dario; Dosio, Guillermo; Aguirrezabal, Luis; García-García, Francisco; Conesa, Ana; Hopp, Esteban; Dopazo, Joaquín; Heinz, Ruth Amelia; Paniego, Norma

    2012-01-01

    Oligonucleotide-based microarrays with accurate gene coverage represent a key strategy for transcriptional studies in orphan species such as sunflower, H. annuus L., which lacks full genome sequences. The goal of this study was the development and functional annotation of a comprehensive sunflower unigene collection and the design and validation of a custom sunflower oligonucleotide-based microarray. A large scale EST (>130,000 ESTs) curation, assembly and sequence annotation was performed using Blast2GO (www.blast2go.de). The EST assembly comprises 41,013 putative transcripts (12,924 contigs and 28,089 singletons). The resulting Sunflower Unigen Resource (SUR version 1.0) was used to design an oligonucleotide-based Agilent microarray for cultivated sunflower. This microarray includes a total of 42,326 features: 1,417 Agilent controls, 74 control probes for sunflower replicated 10 times (740 controls) and 40,169 different non-control probes. Microarray performance was validated using a model experiment examining the induction of senescence by water deficit. Pre-processing and differential expression analysis of Agilent microarrays was performed using the Bioconductor limma package. The analyses based on p-values calculated by eBayes (psunflower unigene collection, and a custom, validated sunflower oligonucleotide-based microarray using Agilent technology. Both the curated unigene collection and the validated oligonucleotide microarray provide key resources for sunflower genome analysis, transcriptional studies, and molecular breeding for crop improvement.

  3. Species-specific SSR alleles for studies of hybrid cattails (Typha latifolia x T. angustifolia; Typhaceae) in North America.

    Science.gov (United States)

    Snow, Allison A; Travis, Steven E; Wildová, Radka; Fér, Tomás; Sweeney, Patricia M; Marburger, Joy E; Windels, Steven; Kubátová, Barbora; Goldberg, Deborah E; Mutegi, Evans

    2010-12-01

    Studies of hybridizing species are facilitated by the availability of species-specific molecular markers for identifying early- and later-generation hybrids. Cattails are a dominant feature of wetland communities, and a better understanding of the prevalence of hybrids is needed to assess the ecological and evolutionary effects of hybridization. Hybridization between Typha angustifolia and T. latifolia produce long-lived clones, known as Typha ×glauca, which are considered to be invasive. Although morphological variation in cattails makes it difficult to recognize early- and later-generation hybrids, several dominant, species-specific RAPD markers are available. Our goal was to find codominant, species-specific markers with greater polymorphism than RAPDs, to identify later-generation hybrids more efficiently. • We screened nine SSR (simple sequence repeat) loci that were described from populations in Ukraine, and we surveyed 31 cattail populations from the upper Midwest and eastern USA. • Seven SSR loci distinguished the parent taxa and were consistent with known species-specific RAPD markers, allowing easier detection of backcrossing. We used linear discriminant analysis to show that F(1) hybrid phenotypes were intermediate between the parent taxa, while those of backcrossed plants overlapped with the hybrids and their parents. Log(leaf length/leaf width), spike gap length, spike length, and stem diameter explained much of the variation among groups. • We provide the first documentation of backcrossed plants in hybridizing cattail populations in Michigan. The diagnostic SSR loci we identified should be extremely useful for examining the evolutionary and ecology interactions of hybridizing cattails in North America.

  4. Combining ability's for yield components in sunflower

    Directory of Open Access Journals (Sweden)

    Hladni Nada

    2000-01-01

    Full Text Available In order to develop new single-cross sunflower hybrids with an altered plant model and a high genetic potential for seed yield and oil content, it is essential to study the combining ability's of the inbred lines. Full diallel crosses with six genetically divergent sunflower inbreeds were carried out in order to study the mode of inheritance and combining ability for plant height and head diameter in the F1 and F2 generations. Significant differences in the mean values for the traits concerned were observed. The most common mode of inheritance of plant height in the F1 and F2 generations was super dominance, and there were also instances of partial dominance and dominance. The mode of inheritance of head diameter in the F1 and F2 generations was dominance and super dominance. Highly significant GCA and SCA value, for plant height and head diameter were recorded. We found a line (NS-NDF with negative GCA value that was also a good genera 1 combiner for reduced plant height and head diameter. .

  5. Hybridization of laboratory strains of sibling species A and B of Anopheles quadrimaculatus.

    Science.gov (United States)

    Kaiser, P E; Mitchell, S E; Lanzaro, G C; Seawright, J A

    1988-03-01

    Adult mosquitoes of the Anopheles quadrimaculatus complex were collected from Montgomery County, AL (MON) and Alachua County, FL, (KBG) and laboratory stocks of species A and B were established through a selection procedure employing isofemale lines. Progeny from a cross of species B females to ORL males were usually semisterile females and sterile males. Progeny of the reciprocal cross were also semisterile females and sterile males, but the sex ratio was variable and ranged from normal to no males because of male mortality during the pupal stage. Conspecific crosses between strains from the two locations resulted in fertile offspring. Crosses between the sibling species from the two locations invariably gave semisterile females and sterile males (or lethal effects). This evidence confirmed previous data from hybridization and electrophoretic analyses of field populations indicating that Anopheles quadrimaculatus is a species complex.

  6. Expression of anatomical leaf traits in homoploid hybrids between deciduous and evergreen species of Vaccinium.

    Science.gov (United States)

    Piwczyński, M; Ponikierska, A; Puchałka, R; Corral, J M

    2013-05-01

    We investigated the anatomical expression of leaf traits in hybrids between evergreen Vaccinium vitis-idaea and deciduous V. myrtillus. We compared parents from four populations with their respective F1 hybrids and tested whether (i) transgression can be the source of novel anatomical traits in hybrids; (ii) expression of transgressive traits is more probable for traits with similar values in parents and intermediate for more distinct values, as predicted by theory; and (iii) independent origin of hybrids leads to identical trait expression profiles among populations. We found that anatomical leaf traits can be divided into four categories based on their similarity to parents: intermediate, parental-like, transgressive and non-significant. Contrary to the common view, parental-like trait values were equally important in shaping the hybrid profile, as were intermediate traits. Transgression was revealed in 17/144 cases and concerned mainly cell and tissue sizes. As predicted by theory, we observed transgressive segregation more often when there was little phenotypic divergence, but intermediate values when parental traits were differentiated. It is likely that cell and tissue sizes are phylogenetically more conserved due to stabilising selection, whereas traits such as leaf thickness and volume fraction of the intercellular spaces, showing a consistent intermediate pattern across populations, are more susceptible to directional selection. Hybrid populations showed little similarity in expression profile, with only three traits identically expressed across all populations. Thus local adaptation of parental species and specific genetic background may be of importance. © 2012 German Botanical Society and The Royal Botanical Society of the Netherlands.

  7. [DNA fingerprinting of individual species and intergeneric and interspecific hybrids of genera Bos and Bison, subfamily Bovinae].

    Science.gov (United States)

    Vasil'ev, V A; Steklenev, E P; Morozova, E V; Semenova, S K

    2002-04-01

    Genome fingerprinting with a hypervariable minisatellite sequence of phage M13 DNA was used to study the genetic variation in individual species of the genera Bos and Bison (subfamily Bovinae) and in their interspecific and intergeneric hybrids. DNA fingerprints were obtained for domestic cow Bos taurus primigenius, vatussy Bos taurus macroceros, banteng Bos javanicus, gaur Bos gaurus, wisent Bison bonasus, bison Bison bison, and for the interspecific and intergeneric hybrids. Compared with the original species, most hybrids showed a greater variation in number and size of hybridization fragments. An association was revealed between the number of hybridization fragments and blood composition of interspecific hybrids resulting from unique crossing of domestic cow and banteng. Pairwise similarity coefficients were calculated to construct a dendrogram of genetic similarity, which reflected the relationships between the parental species and hybrids varying in blood composition. The applicability of the method for identifying interspecific and intergeneric hybrids and for studying the consequences of distant hybridization in the subfamily Bovinae is discussed.

  8. Characteristic LDH isozyme electrophoretic patterns in six flatfish species in the Trondheimsfjord, Norway and their utility for the detection of natural species hybrids

    KAUST Repository

    He, Song

    2014-11-19

    Abstract: LDH isozyme electrophoretic patterns among 621 specimens of six different flatfish species collected in the Trondheimsfjord, Norway, were characterized by using the isoelectric focusing in polyacrylamide gel (IFPAG) technique. The LDH locus appears to be a reliable tool for species identification in the Trondheimsfjord flatfishes. Hence, these patterns were used to detect and identify potential hybrids, together with morphological traits. Among all the specimens collected during this study no hybrids were detected. From the actual numbers analysed, the natural hybridization rate between European plaice and European flounder in the Trondheimsfjord can be roughly estimated to be less than 1%. This is substantially lower than corresponding values reported from Baltic and Danish waters.

  9. First evidence for interspecific hybridization between invasive goby species Neogobius fluviatilis and Neogobius melanostomus (Teleostei: Gobiidae: Benthophilinae).

    Science.gov (United States)

    Lindner, K; Cerwenka, A F; Brandner, J; Gertzen, S; Borcherding, J; Geist, J; Schliewen, U K

    2013-06-01

    Two hybrids between the monkey goby Neogobius fluviatilis and the round goby Neogobius melanostomus from the Rhine River were identified by genotyping and morphological comparison. These are the first records of goby-hybrids outside the parent species' native ranges worldwide. © 2013 The Authors. Journal of Fish Biology © 2013 The Fisheries Society of the British Isles.

  10. Acetohydroxyacid synthase (AHAS) in vivo assay for screening imidazolinone-resistance in sunflower (Helianthus annuus L.).

    Science.gov (United States)

    Vega, T; Breccia, G; Gil, M; Zorzoli, R; Picardi, L; Nestares, G

    2012-12-01

    The objective of this work was to evaluate the in vivo acetohydroxyacid synthase (AHAS) activity response to imidazolinones and its possible use as a selection method for evaluating AHAS inhibitor resistance. In vivo AHAS assay and the comparison of parameters from dose-response curves have been used as a valid tool for comparing sunflower lines and hybrids differing in imidazolinone resistance. The sunflower resistant genotypes evaluated here were 100-fold and 20-fold more resistant compared with the susceptible line for imazethapyr and imazapyr, respectively. This assay also allowed discrimination of homozygous from heterozygous genotypes for I(mr1) locus that codify for the catalytic subunit of AHAS. The in vivo AHAS assay described in this study was useful for the selection of sunflower genotypes differing in herbicide resistance and could be a useful tool when breeding for imidazolinone resistance in sunflower. Copyright © 2012 Elsevier Masson SAS. All rights reserved.

  11. Long-term persisting hybrid swarm and geographic difference in hybridization pattern: genetic consequences of secondary contact between two Vincetoxicum species (Apocynaceae-Asclepiadoideae).

    Science.gov (United States)

    Li, Yue; Tada, Fumito; Yamashiro, Tadashi; Maki, Masayuki

    2016-01-22

    During glacial periods, glacial advances caused temperate plant extirpation or retreat into localized warmer areas, and subsequent postglacial glacial retreats resulted in range expansions, which facilitated secondary contact of previously allopatric isolated lineages. The evolutionary outcomes of secondary contact, including hybrid zones, dynamic hybrid swarm, and resultant hybrid speciation, depends on the strengths of reproductive barriers that have arisen through epistatic and pleiotropic effects during allopatric isolation. The aim of this study was to demonstrate refugia isolation and subsequent secondary contact between two perennial Asclepioid species and to assess the genetic consequences of the secondary contact. We modeled the range shift of two ecologically distinct Vincetoxicum species using the species distribution model (SDM) and assessed the genetic consequences of secondary contact by combining morphological and genetic approaches. We performed morphometric analysis (592 individuals) and examined 10 nuclear microsatellites (671 individuals) in V. atratum, V. japonicum, and putative hybrid populations. Multivariate analysis, model-based Bayesian analysis, and non-model-based discriminant analysis of principal components confirmed the hybridization between V. atratum and V. japonicum. High pollen fertility and a lack of linkage disequilibrium suggested that the hybrid populations may be self-sustaining and have persisted since V. atratum and V. japonicum came into contact during the post-glacial period. Moreover, our findings show that the pattern of hybridization between V. atratum and V. japonicum is unidirectional and differs among populations. Geographically-isolated hybrid populations exist as genetically distinct hybrid swarms that consist of V. atratum-like genotypes, V. japonicum-like genotypes, or admixed genotypes. In addition, Bayesian-based clustering analysis and coalescent-based estimates of long-term gene flow showed patterns of

  12. Discrimination of Species and Hybrid Detection in Myriophyllum Spp.: an Introduction to Biodiversity Conservation and Invasion Avoidance

    Directory of Open Access Journals (Sweden)

    R Ghahramanzadeh

    2014-03-01

    Full Text Available Minimizing economical loss through introduction of invasive alien species (IAS in local ecosystem is one of the most important issues in biosecurity. The hybridization potential between non-indigenous and native species has raised concerns due mainly to introgression, which can cause extirpation of native species through gene contamination. In the present study, 71 samples belonging to 12 species from Myriophyllum genus were assessed in Plant Breeding group of Wageningen University. Internal transcribed spacer (ITS was used for identification of invasive species from related native and possible hybrid plants. The result showed that based on universal application, high sequence divergence and species discrimination, ITS is a powerful sequence for the identification of invasive species from related non-invasive foreign and native species. In contrast to morphological data, ITS grouped suspected hybrid plants in to M. heterophyllum and demonstrated that they have not resulted from hybridization. These observations suggest that multiple introduction and genetic recombination among different introduced genotypes or genetic pools could be reasons of non-flowering in suspected hybrid plants. Results showed that molecular markers enable to distinguish invasive plant species from their most closely related congeners. This could be helpful with enforcing a ban on important of such invasive which can help to plant ecosystem and biodiversity stability.

  13. Integrated pest management of the banded sunflower moth in cultivated sunflower in North Dakota

    Science.gov (United States)

    Banded sunflower moth, Cochylis hospes Walsingham (Lepidoptera: Tortricidae), is a key insect pest of cultivated sunflowers in North Dakota. We investigated pest management strategies to reduce feeding injury caused by the banded sunflower moth in commercial oilseed and confection sunflower fields l...

  14. Immediate Genetic and Epigenetic Changes in F1 Hybrids Parented by Species with Divergent Genomes in the Rice Genus (Oryza)

    National Research Council Canada - National Science Library

    Wu, Ying; Sun, Yue; Shen, Kun; Sun, Shuai; Wang, Jie; Jiang, Tingting; Cao, Shuai; Josiah, Samuel Manthi; Pang, Jinsong; Lin, Xiuyun; Liu, Bao

    2015-01-01

    ..., Oryza, remain largely unknown. We investigated the immediate chromosomal and molecular genetic/epigenetic instability of three triploid F1 hybrids produced by inter-specific crossing between species with divergent...

  15. Genetic origin and composition of a natural hybrid poplar Populus × jrtyschensis from two distantly related species.

    Science.gov (United States)

    Jiang, Dechun; Feng, Jianju; Dong, Miao; Wu, Guili; Mao, Kangshan; Liu, Jianquan

    2016-04-18

    The factors that contribute to and maintain hybrid zones between distinct species are highly variable, depending on hybrid origins, frequencies and fitness. In this study, we aimed to examine genetic origins, compositions and possible maintenance of Populus × jrtyschensis, an assumed natural hybrid between two distantly related species. This hybrid poplar occurs mainly on the floodplains along the river valleys between the overlapping distributions of the two putative parents. We collected 566 individuals from 45 typical populations of P. × jrtyschensis, P. nigra and P. laurifolia. We genotyped them based on the sequence variations of one maternally inherited chloroplast DNA (cpDNA) fragment and genetic polymorphisms at 20 SSR loci. We further sequenced eight nuclear genes for 168 individuals from 31 populations. Two groups of cpDNA haplotypes characteristic of P. nigra and P. laurifolia respectively were both recovered for P. × jrtyschensis. Genetic structures and coalescent tests of two sets of nuclear population genetic data suggested that P. × jrtyschensis originated from hybridizations between the two assumed parental species. All examined populations of P. × jrtyschensis comprise mainly F1 hybrids from interspecific hybridizations between P. nigra and P. laurifolia. In the habitats of P. × jrtyschensis, there are lower concentrations of soil nitrogen than in the habitats occupied by the other two species. Our extensive examination of the genetic composition of P. × jrtyschensis suggested that it is typical of F1-dominated hybrid zones. This finding plus the low concentration of soil nitrogen in the floodplain soils support the F1-dominated bounded hybrid superiority hypothesis of hybrid zone maintenance for this particular hybrid poplar.

  16. Mycoflora of phylloplane as a factor protecting the oil sunflower against the diseases caused by fungi, depending on ecological conditions

    Directory of Open Access Journals (Sweden)

    Włodzimierz Kita

    2014-08-01

    Full Text Available In the years 1980-83 a research was carried out on the phylloplane of oil sunflowers. A composition of species of the fungus community was determined as well as its reaction in relation to the sunflower pathogens: Botrytis cinerea and Sclerotinia sclerotiorum.

  17. Genetic diversity and population structure of the endangered whorled sunflower, Helianthus verticillatus, at two sites in Georgia

    Science.gov (United States)

    Helianthus verticillatus, the whorled sunflower, is an endangered species endemic to only a few locations in Tennessee, Alabama, and Georgia. This sunflower is an aggressive grower and attractive to both plant enthusiasts and pollinators with its multiple, small yellow flowers in late fall. There is...

  18. A Transcriptomic Analysis of Cave, Surface, and Hybrid Isopod Crustaceans of the Species Asellus aquaticus.

    Science.gov (United States)

    Stahl, Bethany A; Gross, Joshua B; Speiser, Daniel I; Oakley, Todd H; Patel, Nipam H; Gould, Douglas B; Protas, Meredith E

    2015-01-01

    Cave animals, compared to surface-dwelling relatives, tend to have reduced eyes and pigment, longer appendages, and enhanced mechanosensory structures. Pressing questions include how certain cave-related traits are gained and lost, and if they originate through the same or different genetic programs in independent lineages. An excellent system for exploring these questions is the isopod, Asellus aquaticus. This species includes multiple cave and surface populations that have numerous morphological differences between them. A key feature is that hybrids between cave and surface individuals are viable, which enables genetic crosses and linkage analyses. Here, we advance this system by analyzing single animal transcriptomes of Asellus aquaticus. We use high throughput sequencing of non-normalized cDNA derived from the head of a surface-dwelling male, the head of a cave-dwelling male, the head of a hybrid male (produced by crossing a surface individual with a cave individual), and a pooled sample of surface embryos and hatchlings. Assembling reads from surface and cave head RNA pools yielded an integrated transcriptome comprised of 23,984 contigs. Using this integrated assembly as a reference transcriptome, we aligned reads from surface-, cave- and hybrid- head tissue and pooled surface embryos and hatchlings. Our approach identified 742 SNPs and placed four new candidate genes to an existing linkage map for A. aquaticus. In addition, we examined SNPs for allele-specific expression differences in the hybrid individual. All of these resources will facilitate identification of genes and associated changes responsible for cave adaptation in A. aquaticus and, in concert with analyses of other species, will inform our understanding of the evolutionary processes accompanying adaptation to the subterranean environment.

  19. A Transcriptomic Analysis of Cave, Surface, and Hybrid Isopod Crustaceans of the Species Asellus aquaticus.

    Directory of Open Access Journals (Sweden)

    Bethany A Stahl

    Full Text Available Cave animals, compared to surface-dwelling relatives, tend to have reduced eyes and pigment, longer appendages, and enhanced mechanosensory structures. Pressing questions include how certain cave-related traits are gained and lost, and if they originate through the same or different genetic programs in independent lineages. An excellent system for exploring these questions is the isopod, Asellus aquaticus. This species includes multiple cave and surface populations that have numerous morphological differences between them. A key feature is that hybrids between cave and surface individuals are viable, which enables genetic crosses and linkage analyses. Here, we advance this system by analyzing single animal transcriptomes of Asellus aquaticus. We use high throughput sequencing of non-normalized cDNA derived from the head of a surface-dwelling male, the head of a cave-dwelling male, the head of a hybrid male (produced by crossing a surface individual with a cave individual, and a pooled sample of surface embryos and hatchlings. Assembling reads from surface and cave head RNA pools yielded an integrated transcriptome comprised of 23,984 contigs. Using this integrated assembly as a reference transcriptome, we aligned reads from surface-, cave- and hybrid- head tissue and pooled surface embryos and hatchlings. Our approach identified 742 SNPs and placed four new candidate genes to an existing linkage map for A. aquaticus. In addition, we examined SNPs for allele-specific expression differences in the hybrid individual. All of these resources will facilitate identification of genes and associated changes responsible for cave adaptation in A. aquaticus and, in concert with analyses of other species, will inform our understanding of the evolutionary processes accompanying adaptation to the subterranean environment.

  20. Occasional hybridization between a native and invasive Senecio species in Australia is unlikely to contribute to invasive success.

    Science.gov (United States)

    Dormontt, Eleanor E; Prentis, Peter J; Gardner, Michael G; Lowe, Andrew J

    2017-01-01

    Hybridization between native and invasive species can facilitate introgression of native genes that increase invasive potential by providing exotic species with pre-adapted genes suitable for new environments. In this study we assessed the outcome of hybridization between native Senecio pinnatifolius var. pinnatifolius A.Rich. (dune ecotype) and invasive Senecio madagascariensis Poir. to investigate the potential for introgression of adaptive genes to have facilitated S. madagascariensis spread in Australia. We used amplified fragment length polymorphisms (141 loci) and nuclear microsatellites (2 loci) to genotype a total of 118 adults and 223 seeds from S. pinnatifolius var.pinnatifolius and S. madagascariensis at one allopatric and two shared sites. We used model based clustering and assignment methods to establish whether hybrid seed set and mature hybrids occur in the field. We detected no adult hybrids in any population. Low incidence of hybrid seed set was found at Lennox Head where the contact zone overlapped for 20 m (6% and 22% of total seeds sampled for S. pinnatifolius var. pinnatifolius and S. madagascariensis respectively). One hybrid seed was detected at Ballina where a gap of approximately 150 m was present between species (2% of total seeds sampled for S. madagascariensis). We found no evidence of adult hybrid plants at two shared sites. Hybrid seed set from both species was identified at low levels. Based on these findings we conclude that introgression of adaptive genes from S. pinnatifolius var. pinnatifolius is unlikely to have facilitated S. madagascariensis invasions in Australia. Revisitation of one site after two years could find no remaining S. pinnatifolius var. pinnatifolius, suggesting that contact zones between these species are dynamic and that S. pinnatifolius var. pinnatifolius may be at risk of displacement by S. madagascariensis in coastal areas.

  1. Occasional hybridization between a native and invasive Senecio species in Australia is unlikely to contribute to invasive success

    Directory of Open Access Journals (Sweden)

    Eleanor E. Dormontt

    2017-08-01

    Full Text Available Background Hybridization between native and invasive species can facilitate introgression of native genes that increase invasive potential by providing exotic species with pre-adapted genes suitable for new environments. In this study we assessed the outcome of hybridization between native Senecio pinnatifolius var. pinnatifolius A.Rich. (dune ecotype and invasive Senecio madagascariensis Poir. to investigate the potential for introgression of adaptive genes to have facilitated S. madagascariensis spread in Australia. Methods We used amplified fragment length polymorphisms (141 loci and nuclear microsatellites (2 loci to genotype a total of 118 adults and 223 seeds from S. pinnatifolius var.pinnatifolius and S. madagascariensis at one allopatric and two shared sites. We used model based clustering and assignment methods to establish whether hybrid seed set and mature hybrids occur in the field. Results We detected no adult hybrids in any population. Low incidence of hybrid seed set was found at Lennox Head where the contact zone overlapped for 20 m (6% and 22% of total seeds sampled for S. pinnatifolius var. pinnatifolius and S. madagascariensis respectively. One hybrid seed was detected at Ballina where a gap of approximately 150 m was present between species (2% of total seeds sampled for S. madagascariensis. Conclusions We found no evidence of adult hybrid plants at two shared sites. Hybrid seed set from both species was identified at low levels. Based on these findings we conclude that introgression of adaptive genes from S. pinnatifolius var. pinnatifolius is unlikely to have facilitated S. madagascariensis invasions in Australia. Revisitation of one site after two years could find no remaining S. pinnatifolius var. pinnatifolius, suggesting that contact zones between these species are dynamic and that S. pinnatifolius var. pinnatifolius may be at risk of displacement by S. madagascariensis in coastal areas.

  2. Biological and genetic aspects of experimental hybrids from species of the Phyllosoma complex (Hemiptera: Reduviidae: Triatominae

    Directory of Open Access Journals (Sweden)

    José Alejandro Martínez-Ibarra

    2008-05-01

    Full Text Available The present work is a thorough investigation of the degree of reproductive isolation between Meccus mazzottii and Meccus longipennis, Meccus picturatus, Meccus pallidipennis and Meccus bassolsae, as well as between M. longipennis and M. picturatus. We examined fertility and segregation of morphological characteristics in two generations of hybrids derived from crosses between these species. The percentage of pairs with (fertile offspring was highest in the set of crosses between M. longipennis and M. picturatus, and lowest between M. mazzottii and M. picturatus. Most first-generation (F1 individuals from crosses involving M. mazzottii were morphologically similar to this species, while only F1 x F1 progeny of parental crosses between M. mazzottii and M. longipennis had offspring second generation that looked like M. mazzottii. The results indicate that different degrees of reproductive isolation apparently exist among the species of the Phyllosoma complex examined in this study. The biological evidence obtained in this study does not support the proposal that M. longipennis and M. picturatus are full species. It could indicate on the contrary, that both could be considered as subspecies of a single polytypic species. On the other hand, biological evidence supports the proposal that M. mazzottii is a full species.

  3. Biological and genetic aspects of experimental hybrids from species of the Phyllosoma complex (Hemiptera: Reduviidae: Triatominae).

    Science.gov (United States)

    Martínez-Ibarra, José Alejandro; Ventura-Rodríguez, Luz Verónica; Meillon-Isais, Karla; Barajas-Martínez, Héctor; Alejandre-Aguilar, Ricardo; Lupercio-Coronel, Patricia; Rocha-Chávez, Gonzalo; Nogueda-Torres, Benjamín

    2008-05-01

    The present work is a thorough investigation of the degree of reproductive isolation between Meccus mazzottii and Meccus longipennis, Meccus picturatus, Meccus pallidipennis and Meccus bassolsae, as well as between M. longipennis and M. picturatus. We examined fertility and segregation of morphological characteristics in two generations of hybrids derived from crosses between these species. The percentage of pairs with (fertile) offspring was highest in the set of crosses between M. longipennis and M. picturatus, and lowest between M. mazzottii and M. picturatus. Most first-generation (F1) individuals from crosses involving M. mazzottii were morphologically similar to this species, while only F1 x F1 progeny of parental crosses between M. mazzottii and M. longipennis had offspring second generation that looked like M. mazzottii. The results indicate that different degrees of reproductive isolation apparently exist among the species of the Phyllosoma complex examined in this study. The biological evidence obtained in this study does not support the proposal that M. longipennis and M. picturatus are full species. It could indicate on the contrary, that both could be considered as subspecies of a single polytypic species. On the other hand, biological evidence supports the proposal that M. mazzottii is a full species.

  4. Evidence for mito-nuclear and sex-linked reproductive barriers between the hybrid Italian sparrow and its parent species.

    Science.gov (United States)

    Trier, Cassandra N; Hermansen, Jo S; Sætre, Glenn-Peter; Bailey, Richard I

    2014-01-01

    Studies of reproductive isolation between homoploid hybrid species and their parent species have rarely been carried out. Here we investigate reproductive barriers between a recently recognized hybrid bird species, the Italian sparrow Passer italiae and its parent species, the house sparrow P. domesticus and Spanish sparrow P. hispaniolensis. Reproductive barriers can be difficult to study in hybrid species due to lack of geographical contact between taxa. However, the Italian sparrow lives parapatrically with the house sparrow and both sympatrically and parapatrically with the Spanish sparrow. Through whole-transcriptome sequencing of six individuals of each of the two parent species we identified a set of putatively parent species-diagnostic single nucleotide polymorphism (SNP) markers. After filtering for coverage, genotyping success (>97%) and multiple SNPs per gene, we retained 86 species-informative, genic, nuclear and mitochondrial SNP markers from 84 genes for analysis of 612 male individuals. We show that a disproportionately large number of sex-linked genes, as well as the mitochondria and nuclear genes with mitochondrial function, exhibit sharp clines at the boundaries between the hybrid and the parent species, suggesting a role for mito-nuclear and sex-linked incompatibilities in forming reproductive barriers. We suggest that genomic conflict via interactions between mitochondria and sex-linked genes with mitochondrial function ("mother's curse") at one boundary and centromeric drive at the other may best explain our findings. Hybrid speciation in the Italian sparrow may therefore be influenced by mechanisms similar to those involved in non-hybrid speciation, but with the formation of two geographically separated species boundaries instead of one. Spanish sparrow alleles at some loci have spread north to form reproductive barriers with house sparrows, while house sparrow alleles at different loci, including some on the same chromosome, have spread in

  5. Evidence for Mito-Nuclear and Sex-Linked Reproductive Barriers between the Hybrid Italian Sparrow and Its Parent Species

    Science.gov (United States)

    Sætre, Glenn-Peter; Bailey, Richard I.

    2014-01-01

    Studies of reproductive isolation between homoploid hybrid species and their parent species have rarely been carried out. Here we investigate reproductive barriers between a recently recognized hybrid bird species, the Italian sparrow Passer italiae and its parent species, the house sparrow P. domesticus and Spanish sparrow P. hispaniolensis. Reproductive barriers can be difficult to study in hybrid species due to lack of geographical contact between taxa. However, the Italian sparrow lives parapatrically with the house sparrow and both sympatrically and parapatrically with the Spanish sparrow. Through whole-transcriptome sequencing of six individuals of each of the two parent species we identified a set of putatively parent species-diagnostic single nucleotide polymorphism (SNP) markers. After filtering for coverage, genotyping success (>97%) and multiple SNPs per gene, we retained 86 species-informative, genic, nuclear and mitochondrial SNP markers from 84 genes for analysis of 612 male individuals. We show that a disproportionately large number of sex-linked genes, as well as the mitochondria and nuclear genes with mitochondrial function, exhibit sharp clines at the boundaries between the hybrid and the parent species, suggesting a role for mito-nuclear and sex-linked incompatibilities in forming reproductive barriers. We suggest that genomic conflict via interactions between mitochondria and sex-linked genes with mitochondrial function (“mother's curse”) at one boundary and centromeric drive at the other may best explain our findings. Hybrid speciation in the Italian sparrow may therefore be influenced by mechanisms similar to those involved in non-hybrid speciation, but with the formation of two geographically separated species boundaries instead of one. Spanish sparrow alleles at some loci have spread north to form reproductive barriers with house sparrows, while house sparrow alleles at different loci, including some on the same chromosome, have spread

  6. Evidence for mito-nuclear and sex-linked reproductive barriers between the hybrid Italian sparrow and its parent species.

    Directory of Open Access Journals (Sweden)

    Cassandra N Trier

    2014-01-01

    Full Text Available Studies of reproductive isolation between homoploid hybrid species and their parent species have rarely been carried out. Here we investigate reproductive barriers between a recently recognized hybrid bird species, the Italian sparrow Passer italiae and its parent species, the house sparrow P. domesticus and Spanish sparrow P. hispaniolensis. Reproductive barriers can be difficult to study in hybrid species due to lack of geographical contact between taxa. However, the Italian sparrow lives parapatrically with the house sparrow and both sympatrically and parapatrically with the Spanish sparrow. Through whole-transcriptome sequencing of six individuals of each of the two parent species we identified a set of putatively parent species-diagnostic single nucleotide polymorphism (SNP markers. After filtering for coverage, genotyping success (>97% and multiple SNPs per gene, we retained 86 species-informative, genic, nuclear and mitochondrial SNP markers from 84 genes for analysis of 612 male individuals. We show that a disproportionately large number of sex-linked genes, as well as the mitochondria and nuclear genes with mitochondrial function, exhibit sharp clines at the boundaries between the hybrid and the parent species, suggesting a role for mito-nuclear and sex-linked incompatibilities in forming reproductive barriers. We suggest that genomic conflict via interactions between mitochondria and sex-linked genes with mitochondrial function ("mother's curse" at one boundary and centromeric drive at the other may best explain our findings. Hybrid speciation in the Italian sparrow may therefore be influenced by mechanisms similar to those involved in non-hybrid speciation, but with the formation of two geographically separated species boundaries instead of one. Spanish sparrow alleles at some loci have spread north to form reproductive barriers with house sparrows, while house sparrow alleles at different loci, including some on the same chromosome

  7. INTEGRATED NITROGEN AND BORON FERTILIZATION IMPROVES THE PRODUCTIVITY AND OIL QUALITY OF SUNFLOWER GROWN IN A CALCAREOUS SOIL

    OpenAIRE

    SHEHZAD, Muhammad Asif; MAQSOOD, Muhammad

    2015-01-01

    Among biotic and abiotic factors, imbalanced plant nutrition is more indispensable for low sunflower productivity. To assess the interaction behavior of nitrogen with boron on sunflower growth, yield and its oil quality in alkaline-calcareous soils, a field experiment was conducted for two consecutive growing seasons of 2011 and 2012. Sunflower hybrid (Helianthus annuus ‘Hysun-33’) was grown on sandy clay loam soil that was amended with diverse boron rates of 0, 2, 4, and 6 kg ha-1 under vari...

  8. Changes in sunflower breeding over the last fifty years

    Directory of Open Access Journals (Sweden)

    Vear Felicity

    2016-03-01

    Full Text Available This article discusses changes in sunflower breeding objectives since the introduction of hybrid varieties 50 years ago. After a reminder of the importance of some early programmes, Canadian in particular, the present situation for each breeding objective is compared with those encountered earlier. Breeding for yield has changed from maximum possible yield under intensive agriculture to yield with resistance to abiotic stresses, moderate droughts and shallow soils in particular, helped by collaboration with agronomists to produce crop models. Breeding for oil has changed from quantity to quality and the value of seed meal is again becoming economically important. Necessary disease resistances vary with agronomic practises and selection pressure on pathogens according to varietal genetics. The possibilities of new types of sunflower are also discussed. Advances in genomics will change breeding procedures, but with rapidly changing molecular techniques, international collaboration is particularly important.

  9. Sunflower 1000-seed weight as affected by year and genotype

    Directory of Open Access Journals (Sweden)

    Radić Velimir

    2013-01-01

    Full Text Available For a successful seed production, it is necessary to know the size, i.e. 1000-seed weight, since it affects the sowing rate, plant density over the vegetative period as well as the seed yield per unit area. The study was conducted in field conditions, on plots where seed production of sunflower hybrids parental components was organized. Seed production was based at three different localities. Observation was conducted during the course of three years. The study was performed on 18 different genotypes. Considering the total number of the observed genotypes, 10 genotypes represented lines based on CMS, while the remaining 8 genotypes represented restorer lines. The study showed that 1000-seed weight was higher with CMS based lines than with restorer lines, which was expected considering the branching of the restorer lines. Sunflower 1000-seed weight depended on the year of observation and the observed genotype. Year had a significant effect on 1000-seed weight.

  10. Possible natural hybridization of two morphologically distinct species of Acropora (Cnidaria, Scleractinia in the Pacific: fertilization and larval survival rates.

    Directory of Open Access Journals (Sweden)

    Naoko Isomura

    Full Text Available Natural hybridization of corals in the Indo-Pacific has been considered rather rare. However, field studies have observed many corals with intermediate interspecific or unusual morphologies. Given that the existence of F1 hybrids with intermediate interspecific morphologies has been proven in the Caribbean, hybrids may also inhabit the Indo-Pacific and occur more frequently than expected. In this study, we focused on two morphologically different species, Acropora florida and A. intermedia, and performed crossing experiments at Akajima Island, Japan. Results showed that these species could hybridize in both directions via eggs and sperm, but that fertilization rates significantly differed according to which species provided eggs. These results are similar to those reported from the Caribbean. Although all embryos developed normally to the planular larval stage, the developmental processes of some hybrid embryos were delayed by approximately 1 h compared with conspecific embryos, suggesting that fertilization occurred 1 h later in interspecific crosses than in intraspecific crosses. More successful hybridization could occur under conditions with low numbers of conspecific colonies. Additionally, a comparison of survival rates between hybrid and intraspecific larvae revealed that intra- and interspecific larvae produced from eggs of A. florida survived for significantly longer than those produced from eggs of A. intermedia. Considering these data, under specific conditions, hybrids can be expected to be produced and survive in nature in the Pacific. Furthermore, we identified one colony with intermediate morphology between A. florida and A. intermedia in the field. This colony was fertilized only by eggs of A. florida, with high fertilization rates, suggesting that this colony would be a hybrid of these two species and might be backcrossed.

  11. Rhizobium helianthi sp. nov., isolated from the rhizosphere of sunflower.

    Science.gov (United States)

    Wei, Xuexin; Yan, Shouwei; Li, Dai; Pang, Huancheng; Li, Yuyi; Zhang, Jianli

    2015-12-01

    A Gram-stain-negative, non-spore-forming, rod-shaped and aerobic bacterium, designated Xi19T, was isolated from a soil sample collected from the rhizosphere of sunflower (Helianthus annuus) in Wuyuan county of Inner Mongolia, China and was characterized taxonomically by using a polyphasic approach. Phylogenetic analysis based on 16S rRNA gene sequences indicated that the novel isolate was related to species of the genus Rhizobium, sharing the greatest 16S rRNA gene sequence similarity with Rhizobium rhizoryzae J3-AN59T (98.4 %), followed by Rhizobium pseudoryzae J3-A127T (97.4 %). There were low similarities ( Rhizobium. DNA-DNA hybridization values between strain Xi19T and the most related strain Rhizobium rhizoryzae J3-AN59T were low. The major cellular fatty acids of strain Xi19T were C16 : 0, summed feature 8 (C18 : 1ω7c and/or C18 : 1ω6c) and C19 : 0 cyclo ω8c. Q-10 was identified as the predominant ubiquinone and the major polar lipids were diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine and phosphatidylcholine. The DNA G+C content of strain Xi19T was 60.2 mol%. On the basis of physiological and biochemical characteristics, coupled with genotypic data obtained in this work, strain Xi19T represents a novel species of the genus Rhizobium, for which the name Rhizobium helianthi is proposed. The type strain is Xi19T ( = CGMCC 1.12192T = KCTC 23879T).

  12. Inter-species hybridization among Neotropical cats of the genus Leopardus, and evidence for an introgressive hybrid zone between L. geoffroyi and L. tigrinus in southern Brazil.

    Science.gov (United States)

    Trigo, T C; Freitas, T R O; Kunzler, G; Cardoso, L; Silva, J C R; Johnson, W E; O'Brien, S J; Bonatto, S L; Eizirik, E

    2008-10-01

    Natural hybrid zones between distinct species have been reported for many taxa, but so far, few examples involve carnivores or Neotropical mammals in general. In this study, we employed mitochondrial DNA (mtDNA) sequences and nine microsatellite loci to identify and characterize a hybrid zone between two Neotropical felids, Leopardus geoffroyi and L. tigrinus, both of which are well-established species having diverged from each other c. 1 million years ago. These two felids are mostly allopatric throughout their ranges in South America, with a narrow contact zone that includes southern Brazil. We present strong evidence for the occurrence of hybridization between these species and identify at least 14 individuals (most of them originating from the geographical contact zone) exhibiting signs of interspecific genomic introgression. The genetic structure of Brazilian L. tigrinus populations seems to be affected by this introgression process, showing a gradient of differentiation from L. geoffroyi correlated with distance from the contact zone. We also corroborate and extend previous findings of hybridization between L. tigrinus and a third related felid, L. colocolo, leading to an unusual situation for a mammal, in which the former species contains introgressed mtDNA lineages from two distinct taxa in addition to its own.

  13. Genetic relationships in Lens species and parentage determination of their interspecific hybrids using RAPD markers.

    Science.gov (United States)

    Ahmad, M; McNeil, D L; Fautrier, A G; Armstrong, K F; Paterson, A M

    1996-06-01

    Broadening of the genetic base and systematic exploitation of heterosis in cultivated lentils requires reliable information on genetic diversity in the germplasm. The ability of random amplified polymorphic DNA (RAPD) to distinguish among different taxa of Lens was evaluated for several geographically dispersed accessions/cultivars of four diploid Lens species. This study was carried out to assess whether RAPD data can provide additional evidence about the origin of the cultivated lentil and to measure genetic variability in lentil germplasm. Three cultivars of Lens culinaris ssp. culinaris, including one microsperma, and two macrosperma types, and four wild species (L. culinaris ssp. orientalis, L. odemensis and L. nigricans) were evaluated for genetic variability using a set of 1 11-mer and 14 random 10-mer primers. One hundred and fifty-eight reproducible and scorable DNA bands were observed from these primers. Genetic distances between each of the accessions were calculated from simple matching coefficients. Split decomposition analysis of the RAPD data allowed construction of an unrooted tree. This study revealed that (1) the level of intraspecific genetic variation in cultivated lentils is narrower than that in some wild species. (2) L. culinaris ssp. orientalis is the most likely candidate as a progenitor of the cultivated species, (3) L. nigricans accession W6 3222 (unknown) and L. c. ssp. orientalis W6 3244 (Turkey) can be reclassified as species of L. odemensis and (4) transmission of genetic material in Lens interspecific hybrids is genotypically specific, as identified by the RAPD markers in our study.

  14. Interspecific hybridization does not affect the level of fluctuating asymmetry (FA) in the Drosophila bipectinata species complex.

    Science.gov (United States)

    Banerjee, Parul; Singh, B N

    2015-08-01

    The Drosophila bipectinata species complex comprises of four very closely related species namely D. bipectinata, D. parabipectinata, D. malerkotliana and D. pseudoananassae. It was found that irrespective of the evolutionary divergence among the species, FA which is reflective of the developmental precision remains nearly same in four species. During the present study, the level of FA in different morphological traits was studied in interspecific hybrids and compared with that of parental species with the view that it would throw light on the degree of divergence between the parental species. If they have not diverged much, the interspecific hybrids may have a similar FA level, incompatibilities between their genomes being negligible. On the other hand, if there is substantial divergence, the level of FA may be higher due to incompatibility between the genomes of the parental species. The morphological traits taken were sternopleural bristle number and wing length in both males and females and ovariole number and sex-comb tooth number in females and males respectively. However, except in a few cases, we could not detect any significant differences in the level of FA in hybrids as compared to pure species. On the other hand, a number of abnormalities like poor viability, dystrophied ovaries, asymmetrical eyes etc., could be detected in hybrids from crosses involving D. pseudoananassae as one of the parents. Therefore, we conclude that specific developmental pathways are more susceptible to developmental disturbances due to genomic incompatibilities than the large complex system bringing about developmental stability.

  15. Separate Location of Parental Chromosomes in Squashed Metaphases of Hybrid between Hordeum vulgare L. and Four Polyploid, Alien Species

    DEFF Research Database (Denmark)

    Jensen, J.; Linde-Laursen, Ib

    1984-01-01

    In 38 squashed, somatic metaphases of four hybrids between diploid Hordeum vulgare and two tetra-and two hexaploid alien species, each of the H. vulgare chromosomes was identifed, and differentiated from the chromosomes of the other parental species, by its Giemsa C-banding pattern. The H. vulgare...

  16. Detection and identification of entamoeba species in stool samples by a reverse line hybridization assay.

    Science.gov (United States)

    Verweij, Jaco J; Laeijendecker, Daphne; Brienen, Eric A T; van Lieshout, Lisette; Polderman, Anton M

    2003-11-01

    Classically, detection of Entamoeba histolytica is performed by microscopic examination for characteristic cysts and/or trophozoites in fecal preparations. Differentiation of E. histolytica cysts and those of nonpathogenic amoebic species is made on the basis of the appearance and the size of the cysts. However, by classical means objective tools for confirmation and quality control do not exist. Therefore, a reverse line blot hybridization assay was developed to detect a variety of Entamoeba species and genetic variants known to infect humans. The assay was performed after amplification with general Entamoeba-specific primers. The assay could identify four genetic variants of Entamoeba polecki-like cysts as well as E. histolytica, Entamoeba dispar, Entamoeba hartmanni, Entamoeba moshkovskii and Entamoeba coli and even mixed infections in a range of controls and fecal samples. This technique can be used as an additional standard for diagnosis, epidemiology, and quality control for amoebic infections.

  17. Progress in modification of sunflower oil to expand its industrial value.

    Science.gov (United States)

    Rauf, Saeed; Jamil, Nazia; Tariq, Sultan Ali; Khan, Maria; Kausar, Maria; Kaya, Yalcin

    2017-05-01

    Increasing the sunflower seed oil content as well as improving its quality makes it compatible for industrial demands. This is an important breeding objective of sunflower which increases its market value and ensures high returns for the producers. The present review focuses on determining the progress of improving sunflower seed oil content and modifying its quality by empirical and advanced molecular breeding methods. It is known that the sunflower oil content and quality have been altered through empirical selection methods and mutation breeding programmes in various parts of the world. Further improvement in seed oil content and its components (such as phytosterols, tocopherols and modified fatty acid profile) has been slowed down due to low genetic variation in elite germplasm and complex of hereditary traits. Introgression from wild species can be carried out to modify the fatty acids profile and tocopherol contents with linkage drags. Different transgenes introduced through biotechnological methods may produce novel long-chain fatty acids within sunflower oil. Bio-engineering of sunflower oil could allow it to be used in diverse industrial products such as bio-diesel or bio-plastics. These results showed that past and current trends of modifying sunflower oil quality are essential for its further expansion as an oilseed crop. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.

  18. Correlation studies on nitrogen for sunflower crop across the agroclimatic variability.

    Science.gov (United States)

    Nasim, Wajid; Belhouchette, Hatem; Tariq, Muhammad; Fahad, Shah; Hammad, Hafiz Mohkum; Mubeen, Muhammad; Munis, Muhammad Farooq Hussain; Chaudhary, Hassan Javed; Khan, Imran; Mahmood, Faisal; Abbas, Tauqeer; Rasul, Fahd; Nadeem, Muhammad; Bajwa, Ali Ahsan; Ullah, Najeeb; Alghabari, Fahad; Saud, Shah; Mubarak, Hussani; Ahmad, Rafiq

    2016-02-01

    Nitrogen (N) fertilizer is an important yield limiting factor for sunflower production. The correlation between yield components and growth parameters of three sunflower hybrids (Hysun-33, Hysun-38, Pioneer-64A93) were studied with five N rates (0, 60, 120, 180, 240 kg ha(-1)) at three different experimental sites during the two consecutive growing seasons 2008 and 2009. The results revealed that total dry matter (TDM) production and grain yield were positively and linearly associated with leaf area index (LAI), leaf area duration (LAD), and crop growth rate (CGR) at all three sites of the experiments. The significant association of yield with growth components indicated that the humid climate was most suitable for sunflower production. Furthermore, the association of these components can be successfully used to predict the grain yield under diverse climatic conditions. The application of N at increased rate of 180 kg ha(-1) resulted in maximum yield as compared to standard rate (120 kg ha(-1)) at all the experimental sites. In this way, N application rate was significantly correlated with growth and development of sunflower under a variety of climatic conditions. Keeping in view such relationship, the N dose can be optimized for sunflower crop in a particular region to maximize the productivity. Multilocation trails help to predict the input rates precisely while taking climatic variations into account also. In the long run, results of this study provides basis for sustainable sunflower production under changing climate.

  19. Cross-species amplification of 41 microsatellites in European cyprinids: A tool for evolutionary, population genetics and hybridization studies

    Directory of Open Access Journals (Sweden)

    Gilles André

    2010-05-01

    Full Text Available Abstract Background Cyprinids display the most abundant and widespread species among the European freshwater Teleostei and are known to hybridize quite commonly. Nevertheless, a limited number of markers for conducting comparative differentiation, evolutionary and hybridization dynamics studies are available to date. Findings Five multiplex PCR sets were optimized in order to assay 41 cyprinid-specific polymorphic microsatellite loci (including 10 novel loci isolated from Chondrostoma nasus nasus, Chondrostoma toxostoma toxostoma and Leuciscus leuciscus for 503 individuals (440 purebred specimens and 63 hybrids from 15 European cyprinid species. The level of genetic diversity was assessed in Alburnus alburnus, Alburnoides bipunctatus, C. genei, C. n. nasus, C. soetta, C. t. toxostoma, L. idus, L. leuciscus, Pachychilon pictum, Rutilus rutilus, Squalius cephalus and Telestes souffia. The applicability of the markers was also tested on Abramis brama, Blicca bjoerkna and Scardinius erythrophtalmus specimens. Overall, between 24 and 37 of these markers revealed polymorphic for the investigated species and 23 markers amplified for all the 15 European cyprinid species. Conclusions The developed set of markers demonstrated its performance in discriminating European cyprinid species. Furthermore, it allowed detecting and characterizing hybrid individuals. These microsatellites will therefore be useful to perform comparative evolutionary and population genetics studies dealing with European cyprinids, what is of particular interest in conservation issues and constitutes a tool of choice to conduct hybridization studies.

  20. Genetic loci with parent-of-origin effects cause hybrid seed lethality in crosses between Mimulus species.

    Science.gov (United States)

    Garner, Austin G; Kenney, Amanda M; Fishman, Lila; Sweigart, Andrea L

    2016-07-01

    In flowering plants, F1 hybrid seed lethality is a common outcome of crosses between closely related diploid species, but the genetic basis of this early-acting and potentially widespread form of postzygotic reproductive isolation is largely unknown. We intercrossed two closely related species of monkeyflower, Mimulus guttatus and Mimulus tilingii, to characterize the mechanisms and strength of postzygotic reproductive isolation. Then, using a reciprocal backcross design, we performed high-resolution genetic mapping to determine the genetic architecture of hybrid seed lethality and directly test for loci with parent-of-origin effects. We found that F1 hybrid seed lethality is an exceptionally strong isolating barrier between Mimulus species, with reciprocal crosses producing < 1% viable seeds. This form of postzygotic reproductive isolation appears to be highly polygenic, indicating that multiple incompatibility loci have accumulated rapidly between these closely related Mimulus species. It is also primarily caused by genetic loci with parent-of-origin effects, suggesting a possible role for imprinted genes in the evolution of Mimulus hybrid seed lethality. Our findings suggest that divergence in loci with parent-of-origin effects, which is probably driven by genomic coevolution within lineages, might be an important source of hybrid incompatibilities between flowering plant species. © 2016 The Authors. New Phytologist © 2016 New Phytologist Trust.

  1. [The demonstration of natural hybridization between two swallowtail species Parnassius nomion and Parnassius bremeri (Lepidoptera, Papilionidae) using RAPD-PCR technique].

    Science.gov (United States)

    Zakharov, E V

    2001-04-01

    Genetic evidence for interspecific hybridization between Parnassius nomion and Parnassius bremeri in nature is presented. To demonstrate hybridization between these species, RAPD analysis was used. By testing 25 decamer primers, three and two diagnostic markers were revealed for P. nomion and P. bremeri, respectively. Out of 28 animals examined, 4 were shown to be interspecific hybrids. According to the distribution of diagnostic markers, the interspecific hybrids were intermediate with regard to the parental species. Ecological and biological characteristics of two swallowtail species that promote their hybridization in nature are discussed.

  2. Discrimination of clostridium species using a magnetic bead based hybridization assay

    Science.gov (United States)

    Pahlow, Susanne; Seise, Barbara; Pollok, Sibyll; Seyboldt, Christian; Weber, Karina; Popp, Jürgen

    2014-05-01

    Clostridium chauvoei is the causative agent of blackleg, which is an endogenous bacterial infection. Mainly cattle and other ruminants are affected. The symptoms of blackleg are very similar to those of malignant edema, an infection caused by Clostridium septicum. [1, 2] Therefore a reliable differentiation of Clostridium chauvoei from other Clostridium species is required. Traditional microbiological detection methods are time consuming and laborious. Additionally, the unique identification is hindered by the overgrowing tendency of swarming Clostridium septicum colonies when both species are present. [1, 3, 4] Thus, there is a crucial need to improve and simplify the specific detection of Clostridium chauvoei and Clostridium septicum. Here we present an easy and fast Clostridium species discrimination method combining magnetic beads and fluorescence spectroscopy. Functionalized magnetic particles exhibit plentiful advantages, like their simple manipulation in combination with a large binding capacity of biomolecules. A specific region of the pathogenic DNA is amplified and labelled with biotin by polymerase chain reaction (PCR). These PCR products were then immobilized on magnetic beads exploiting the strong biotin-streptavidin interaction. The specific detection of different Clostridium species is achieved by using fluorescence dye labeled probe DNA for the hybridization with the immobilized PCR products. Finally, the samples were investigated by fluorescence spectroscopy. [5

  3. Effect of water stress on yield and yield components of sunflower ...

    African Journals Online (AJOL)

    A field experiment during year 2009 was conducted in the research station of the University of Tehran, College of Abouraihan in Pakdasht region, Iran. The study was aimed to investigate the effect of water stress on seed yield, yield component and some quantitative traits of four sunflower hybrids namely Azargol, Alstar, ...

  4. Development, characterization and experimental validation of a cultivated sunflower (Helianthus annuus L. gene expression oligonucleotide microarray.

    Directory of Open Access Journals (Sweden)

    Paula Fernandez

    Full Text Available Oligonucleotide-based microarrays with accurate gene coverage represent a key strategy for transcriptional studies in orphan species such as sunflower, H. annuus L., which lacks full genome sequences. The goal of this study was the development and functional annotation of a comprehensive sunflower unigene collection and the design and validation of a custom sunflower oligonucleotide-based microarray. A large scale EST (>130,000 ESTs curation, assembly and sequence annotation was performed using Blast2GO (www.blast2go.de. The EST assembly comprises 41,013 putative transcripts (12,924 contigs and 28,089 singletons. The resulting Sunflower Unigen Resource (SUR version 1.0 was used to design an oligonucleotide-based Agilent microarray for cultivated sunflower. This microarray includes a total of 42,326 features: 1,417 Agilent controls, 74 control probes for sunflower replicated 10 times (740 controls and 40,169 different non-control probes. Microarray performance was validated using a model experiment examining the induction of senescence by water deficit. Pre-processing and differential expression analysis of Agilent microarrays was performed using the Bioconductor limma package. The analyses based on p-values calculated by eBayes (p<0.01 allowed the detection of 558 differentially expressed genes between water stress and control conditions; from these, ten genes were further validated by qPCR. Over-represented ontologies were identified using FatiScan in the Babelomics suite. This work generated a curated and trustable sunflower unigene collection, and a custom, validated sunflower oligonucleotide-based microarray using Agilent technology. Both the curated unigene collection and the validated oligonucleotide microarray provide key resources for sunflower genome analysis, transcriptional studies, and molecular breeding for crop improvement.

  5. Effector Polymorphisms of the Sunflower Downy Mildew Pathogen Plasmopara halstedii and Their Use to Identify Pathotypes from Field Isolates

    Science.gov (United States)

    Gascuel, Quentin; Bordat, Amandine; Sallet, Erika; Pouilly, Nicolas; Carrere, Sébastien; Roux, Fabrice

    2016-01-01

    The obligate biotroph oomycete Plasmopara halstedii causes downy mildew on sunflower crop, Helianthus annuus. The breakdown of several Pl resistance genes used in sunflower hybrids over the last 25 years came along with the appearance of new Pl. halstedii isolates showing modified virulence profiles. In oomycetes, two classes of effector proteins, key players of pathogen virulence, are translocated into the host: RXLR and CRN effectors. We identified 54 putative CRN or RXLR effector genes from transcriptomic data and analyzed their genetic diversity in seven Pl. halstedii pathotypes representative of the species variability. Pl. halstedii effector genes were on average more polymorphic at both the nucleic and protein levels than random non-effector genes, suggesting a potential adaptive dynamics of pathogen virulence over the last 25 years. Twenty-two KASP (Competitive Allele Specific PCR) markers designed on polymorphic effector genes were genotyped on 35 isolates belonging to 14 Pl. halstedii pathotypes. Polymorphism analysis based on eight KASP markers aims at proposing a determination key suitable to classify the eight multi-isolate pathotypes into six groups. This is the first report of a molecular marker set able to discriminate Pl. halstedii pathotypes based on the polymorphism of pathogenicity effectors. Compared to phenotypic tests handling living spores used until now to discriminate Pl. halstedii pathotypes, this set of molecular markers constitutes a first step in faster pathotype diagnosis of Pl. halstedii isolates. Hence, emerging sunflower downy mildew isolates could be more rapidly characterized and thus, assessment of plant resistance breakdown under field conditions should be improved. PMID:26845339

  6. Natural hybridization and asymmetric introgression at the distribution margin of two Buddleja species with a large overlap.

    Science.gov (United States)

    Liao, Rong-Li; Ma, Yong-Peng; Gong, Wei-Chang; Chen, Gao; Sun, Wei-Bang; Zhou, Ren-Chao; Marczewski, Tobias

    2015-06-18

    Natural hybridization in plants is universal and plays an important role in evolution. Based on morphology it has been presumed that hybridization occurred in the genus Buddleja, though genetic studies confirming this assumption have not been conducted to date. The two species B. crispa and B. officinalis overlap in their distributions over a wide range in South-West China, and we aimed to provide genetic evidence for ongoing hybridization in this study. We investigated the occurrence of hybrids between the two species at the southern-most edge of the distribution of B. crispa using five nuclear loci and pollination experiments. The genetic data suggest substantial differentiation between the two species as species-specific alleles are separated by at least 7-28 mutations. The natural hybrids found were nearly all F1s (21 of 23), but backcrosses were detected, and some individuals, morphologically indistinguishable from the parental species, showed introgression. Pollen viability test shows that the percentage of viable pollen grains was 50 ± 4% for B. crispa, and 81 ± 2% for B. officinalis. This difference is highly significant (t = 7.382, p < 0.0001). Hand cross-pollination experiments showed that B. crispa is not successful as pollen-parent, but B. officinalis is able to pollinate B. crispa to produce viable hybrid seed. Inter-specific seed-set is low (8 seeds per fruit, as opposed to about 65 for intra-specific pollinations), suggesting post-zygotic reproductive barriers. In addition, one of the reference populations also suggests a history of introgression at other localities. The occurrence of morphologically intermediate individuals between B. crispa and B. officinalis at Xishan Mountain is unequivocally linked to hybridization and almost all examined individuals of the putative hybrids were likely F1s. Despite pollination experiments indicating higher chances for introgression into B. officinalis (hybrids only produced viable seed when

  7. Sequence-Based Analysis of Structural Organization and Composition of the Cultivated Sunflower (Helianthus annuus L.) Genome

    Science.gov (United States)

    Gill, Navdeep; Buti, Matteo; Kane, Nolan; Bellec, Arnaud; Helmstetter, Nicolas; Berges, Hélène; Rieseberg, Loren H.

    2014-01-01

    Sunflower is an important oilseed crop, as well as a model system for evolutionary studies, but its 3.6 gigabase genome has proven difficult to assemble, in part because of the high repeat content of its genome. Here we report on the sequencing, assembly, and analyses of 96 randomly chosen BACs from sunflower to provide additional information on the repeat content of the sunflower genome, assess how repetitive elements in the sunflower genome are organized relative to genes, and compare the genomic distribution of these repeats to that found in other food crops and model species. We also examine the expression of transposable element-related transcripts in EST databases for sunflower to determine the representation of repeats in the transcriptome and to measure their transcriptional activity. Our data confirm previous reports in suggesting that the sunflower genome is >78% repetitive. Sunflower repeats share very little similarity to other plant repeats such as those of Arabidopsis, rice, maize and wheat; overall 28% of repeats are “novel” to sunflower. The repetitive sequences appear to be randomly distributed within the sequenced BACs. Assuming the 96 BACs are representative of the genome as a whole, then approximately 5.2% of the sunflower genome comprises non TE-related genic sequence, with an average gene density of 18kbp/gene. Expression levels of these transposable elements indicate tissue specificity and differential expression in vegetative and reproductive tissues, suggesting that expressed TEs might contribute to sunflower development. The assembled BACs will also be useful for assessing the quality of several different draft assemblies of the sunflower genome and for annotating the reference sequence. PMID:24833511

  8. Toward a molecular cytogenetic map for cultivated sunflower (Helianthus annuus L.) by landed BAC/BIBAC clones.

    Science.gov (United States)

    Feng, Jiuhuan; Liu, Zhao; Cai, Xiwen; Jan, Chao-Chien

    2013-01-01

    Conventional karyotypes and various genetic linkage maps have been established in sunflower (Helianthus annuus L., 2n = 34). However, the relationship between linkage groups and individual chromosomes of sunflower remains unknown and has considerable relevance for the sunflower research community. Recently, a set of linkage group-specific bacterial /binary bacterial artificial chromosome (BAC/BIBAC) clones was identified from two complementary BAC and BIBAC libraries constructed for cultivated sunflower cv. HA89. In the present study, we used these linkage group-specific clones (~100 kb in size) as probes to in situ hybridize to HA89 mitotic chromosomes at metaphase using the BAC-fluorescence in situ hybridization (FISH) technique. Because a characteristic of the sunflower genome is the abundance of repetitive DNA sequences, a high ratio of blocking DNA to probe DNA was applied to hybridization reactions to minimize the background noise. As a result, all sunflower chromosomes were anchored by one or two BAC/BIBAC clones with specific FISH signals. FISH analysis based on tandem repetitive sequences, such as rRNA genes, has been previously reported; however, the BAC-FISH technique developed here using restriction fragment length polymorphism (RFLP)-derived BAC/BIBAC clones as probes to apply genome-wide analysis is new for sunflower. As chromosome-specific cytogenetic markers, the selected BAC/BIBAC clones that encompass the 17 linkage groups provide a valuable tool for identifying sunflower cytogenetic stocks (such as trisomics) and tracking alien chromosomes in interspecific crosses. This work also demonstrates the potential of using a large-insert DNA library for the development of molecular cytogenetic resources.

  9. Surgeons and suture zones: Hybridization among four surgeonfish species in the Indo-Pacific with variable evolutionary outcomes.

    Science.gov (United States)

    DiBattista, Joseph D; Whitney, Jonathan; Craig, Matthew T; Hobbs, Jean-Paul A; Rocha, Luiz A; Feldheim, Kevin A; Berumen, Michael L; Bowen, Brian W

    2016-08-01

    Closely related species can provide valuable insights into evolutionary processes through comparison of their ecology, geographic distribution and the history recorded in their genomes. In the Indo-Pacific, many reef fishes are divided into sister species that come into secondary contact at biogeographic borders, most prominently where Indian Ocean and Pacific Ocean faunas meet. It is unclear whether hybridization in this contact zone represents incomplete speciation, secondary contact, an evolutionary dead-end (for hybrids) or some combination of the above. To address these issues, we conducted comprehensive surveys of two widely-distributed surgeonfish species, Acanthurus leucosternon (N=141) and A. nigricans (N=412), with mtDNA cytochrome b sequences and ten microsatellite loci. These surgeonfishes are found primarily in the Indian and Pacific Oceans, respectively, but overlap at the Christmas and Cocos-Keeling Islands hybrid zone in the eastern Indian Ocean. We also sampled the two other Pacific members of this species complex, A. achilles (N=54) and A. japonicus (N=49), which are known to hybridize with A. nigricans where their ranges overlap. Our results indicate separation between the four species that range from the recent Pleistocene to late Pliocene (235,000-2.25million years ago). The Pacific A. achilles is the most divergent (and possibly ancestral) species with mtDNA dcorr≈0.04, whereas the other two Pacific species (A. japonicus and A. nigricans) are distinguishable only at a population or subspecies level (ΦST=0.6533, P<0.001). Little population structure was observed within species, with evidence of recent population expansion across all four geographic ranges. We detected sharing of mtDNA haplotypes between species and extensive hybridization based on microsatellites, consistent with later generation hybrids but also the effects of allele homoplasy. Despite extensive introgression, 98% of specimens had concordance between mtDNA lineage and

  10. Surgeons and suture zones: Hybridization among four surgeonfish species in the Indo-Pacific with variable evolutionary outcomes

    KAUST Repository

    DiBattista, Joseph

    2016-04-30

    Closely related species can provide valuable insights into evolutionary processes through comparison of their ecology, geographic distribution and the history recorded in their genomes. In the Indo-Pacific, many reef fishes are divided into sister species that come into secondary contact at biogeographic borders, most prominently where Indian Ocean and Pacific Ocean faunas meet. It is unclear whether hybridization in this contact zone represents incomplete speciation, secondary contact, an evolutionary dead-end (for hybrids) or some combination of the above. To address these issues, we conducted comprehensive surveys of two widely-distributed surgeonfish species, Acanthurus leucosternon (N = 141) and A. nigricans (N = 412), with mtDNA cytochrome b sequences and ten microsatellite loci. These surgeonfishes are found primarily in the Indian and Pacific Oceans, respectively, but overlap at the Christmas and Cocos-Keeling Islands hybrid zone in the eastern Indian Ocean. We also sampled the two other Pacific members of this species complex, A. achilles (N = 54) and A. japonicus (N = 49), which are known to hybridize with A. nigricans where their ranges overlap. Our results indicate separation between the four species that range from the recent Pleistocene to late Pliocene (235,000 to 2.25 million years ago). The Pacific A. achilles is the most divergent (and possibly ancestral) species with mtDNA dcorr ≈ 0.04, whereas the other two Pacific species (A. japonicus and A. nigricans) are distinguishable only at a population or subspecies level (ΦST = 0.6533, P < 0.001). Little population structure was observed within species, with evidence of recent population expansion across all four geographic ranges. We detected sharing of mtDNA haplotypes between species and extensive hybridization based on microsatellites, consistent with later generation hybrids but also the effects of allele homoplasy. Despite extensive introgression, 98% of specimens had concordance between mt

  11. Simultaneous delimitation of species and quantification of interspecific hybridization in Amazonian peacock cichlids (genus cichla) using multi-locus data.

    Science.gov (United States)

    Willis, Stuart C; Macrander, Jason; Farias, Izeni P; Ortí, Guillermo

    2012-06-22

    Introgression likely plays a significant role in evolution, but understanding the extent and consequences of this process requires a clear identification of species boundaries in each focal group. The delimitation of species, however, is a contentious endeavor. This is true not only because of the inadequacy of current tools to identify species lineages, but also because of the inherent ambiguity between natural populations and species paradigms. The result has been a debate about the supremacy of various species concepts and criteria. Here, we utilized multiple separate sources of molecular data, mtDNA, nuclear sequences, and microsatellites, to delimit species under a polytypic species concept (PTSC) and estimate the frequency and genomic extent of introgression in a Neotropical genus of cichlid fishes (Cichla). We compared our inferences of species boundaries and introgression under this paradigm to those when species are identified under a diagnostic species concept (DSC). We find that, based on extensive molecular data and an inclusive species concept, 8 separate biological entities should be recognized rather than the 15 described species of Cichla. Under the PTSC, fewer individuals are expected to exhibit hybrid ancestry than under the DSC (~2% vs. ~12%), but a similar number of the species exhibit introgression from at least one other species (75% vs. 60%). Under either species concept, the phylogenetic breadth of introgression in this group is notable, with both sister species and species from different major mtDNA clades exhibiting introgression. Introgression was observed to be a widespread phenomenon for delimited species in this group. While several instances of introgressive hybridization were observed in anthropogenically altered habitats, most were found in undisturbed natural habitats, suggesting that introgression is a natural but ephemeral part of the evolution of many tropical species. Nevertheless, even transient introgression may facilitate an

  12. Species limits, interspecific hybridization and phylogeny in the cryptic land snail complex Pyramidula: The power of RADseq data.

    Science.gov (United States)

    Razkin, Oihana; Sonet, Gontran; Breugelmans, Karin; Madeira, María José; Gómez-Moliner, Benjamín Juan; Backeljau, Thierry

    2016-08-01

    Restriction site-associated DNA sequencing (RADseq) was used to jointly assess phylogenetic relationships, interspecific hybridization and species delimitation in the cryptic, non-model land snail complex Pyramidula. A robust phylogeny was inferred using a matrix of concatenated sequences of almost 1,500,000bp long, containing >97,000 polymorphic sites. Maximum likelihood analyses fully resolved the phylogenetic relationships among species and drastically improved phylogenetic trees obtained from mtDNA and nDNA gene trees (COI, 16S rRNA, 5.8S rRNA, ITS2 and 28S rRNA sequence data). The best species delimitation scenario was selected on the basis of 875 unlinked single nucleotide polymorphisms, showing that nine Pyramidula species should be distinguished in Europe. Applying D-statistics provided no or weak evidence of interspecific hybridization among Pyramidula, except for some evidence of gene flow between two species. Copyright © 2016 Elsevier Inc. All rights reserved.

  13. Separation and determination of arsenic species in water by selective exchange and hybrid resins

    Energy Technology Data Exchange (ETDEWEB)

    Issa, Nureddin Ben [Faculty of Technology and Metallurgy, University of Belgrade, Karnegijeva 4, Belgrade (Serbia); Rajakovic-Ognjanovic, Vladana N. [Faculty of Civil Engineering, University of Belgrade, Bulevar Kralja Aleksandra 73, Belgrade (Serbia); Marinkovic, Aleksandar D. [Faculty of Technology and Metallurgy, University of Belgrade, Karnegijeva 4, Belgrade (Serbia); Rajakovic, Ljubinka V., E-mail: ljubinka@tmf.bg.ac.rs [Faculty of Technology and Metallurgy, University of Belgrade, Karnegijeva 4, Belgrade (Serbia)

    2011-11-07

    Highlights: {yields} A simple and efficient method for separation and determination of arsenic species. {yields} A new hybrid resin HY-AgCl is effective for iAs and oAs analytical separation. {yields} SBAE resin was convenient for the separation of As(III) from As(V) and oAs species. {yields} HY-Fe resin was convenient for the separation of DMAs(V). - Abstract: A simple and efficient method for separation and determination of inorganic arsenic (iAs) and organic arsenic (oAs) in drinking, natural and wastewater was developed. If arsenic is present in water prevailing forms are inorganic acids of As(III) and As(V). oAs can be found in traces as monomethylarsenic acid, MMA(V), and dimethylarsenic acid, DMAs(V). Three types of resins: a strong base anion exchange (SBAE) and two hybrid (HY) resins: HY-Fe and HY-AgCl, based on the activity of hydrated iron oxides and a silver chloride were investigated. It was found that the sorption processes (ion exchange, adsorption and chemisorptions) of arsenic species on SBAE (ion exchange) and HY resins depend on pH values of water. The quantitative separation of molecular and ionic forms of iAs and oAs was achieved by SBAE and pH adjustment, the molecular form of As(III) that exists in the water at pH <8.0 was not bonded with SBAE, which was convenient for direct determination of As(III) concentration in the effluent. HY-Fe resin retained all arsenic species except DMAs(V), which makes possible direct measurements of this specie in the effluent. HY-AgCl resin retained all iAs which was convenient for direct determination of oAs species concentration in the effluent. The selective bonding of arsenic species on three types of resins makes possible the development of the procedure for measuring and calculation of all arsenic species in water. In order to determine capacity of resins the preliminary investigations were performed in batch system and fixed bed flow system. Resin capacities were calculated according to breakthrough

  14. Abelhas (Hymenoptera: Apoidea visitantes dos capítulos de girassol no recôncavo baiano Bees (Hymenoptera: Apoidea on sunflower flowers in Recôncavo Baiano region, Brazil

    Directory of Open Access Journals (Sweden)

    Cerilene Santiago Machado

    2006-10-01

    Full Text Available O girassol (Helianthus annuus L. é uma espécie de polinização cruzada, cujos principais polinizadores são as abelhas. Este trabalho teve por objetivo obter informações sobre a diversidade de abelhas visitantes nos capítulos de girassol, fornecendo subsídios para identificar os possíveis polinizadores efetivos na região do Recôncavo Baiano. As coletas das abelhas foram realizadas no período de setembro-outubro de 2004, janeiro-fevereiro e maio-junho de 2005 sobre os híbridos de girassol, "AG 920" e "AG 930", cultivados na área experimental de Entomologia do Centro de Ciências Agrárias e Ambientais da Universidade Federal da Bahia, em Cruz das Almas-BA. Um total de 26 espécies de abelhas foram identificadas, sendo que Apis mellifera foi a mais abundante (58,32%, seguida de Nannotrigona testaceicornis (18,53% e Trigona spinipes (11,37%. As demais espécies apresentaram uma freqüência relativa inferior a 5%.Sunflower, Helianthus annuus L., is a cross-pollinating plant whose main pollinator are bees. This work was airmed at getting information about the diversity of visiting bee on sunflower inflorescence, by identifing the possible sunflower pollinators in Recôncavo Baiano region. The bees were collected on September-October of 2004, January-February and May-June of 2005 sunflowers hybrids (AG 920 and AG 930 cultivated in the entomology experimental area of Centro de Ciências Agrárias e Ambiental da Universidade Federal da Bahia, Brazil. Twenty six species were identified Apis mellifera (58.32%, Nannotrigona testaceicornis (18.53% and Trigona spinipes (11.37% were the most abundant species. The other species presented a frequency lower than relative 5%.

  15. De novo hybrid assembly of the rubber tree genome reveals evidence of paleotetraploidy in Hevea species.

    Science.gov (United States)

    Pootakham, Wirulda; Sonthirod, Chutima; Naktang, Chaiwat; Ruang-Areerate, Panthita; Yoocha, Thippawan; Sangsrakru, Duangjai; Theerawattanasuk, Kanikar; Rattanawong, Ratchanee; Lekawipat, Napawan; Tangphatsornruang, Sithichoke

    2017-02-02

    Para rubber tree (Hevea brasiliensis) is an important economic species as it is the sole commercial producer of high-quality natural rubber. Here, we report a de novo hybrid assembly of BPM24 accession, which exhibits resistance to major fungal pathogens in Southeast Asia. Deep-coverage 454/Illumina short-read and Pacific Biosciences (PacBio) long-read sequence data were acquired to generate a preliminary draft, which was subsequently scaffolded using a long-range "Chicago" technique to obtain a final assembly of 1.26 Gb (N50 = 96.8 kb). The assembled genome contains 69.2% repetitive sequences and has a GC content of 34.31%. Using a high-density SNP-based genetic map, we were able to anchor 28.9% of the genome assembly (363 Mb) associated with over two thirds of the predicted protein-coding genes into rubber tree's 18 linkage groups. These genetically anchored sequences allowed comparative analyses of the intragenomic homeologous synteny, providing the first concrete evidence to demonstrate the presence of paleotetraploidy in Hevea species. Additionally, the degree of macrosynteny conservation observed between rubber tree and cassava strongly supports the hypothesis that the paleotetraploidization event took place prior to the divergence of the Hevea and Manihot species.

  16. Practical identification of eight medically important Trichosporon species by reverse line blot hybridization (RLB) assay and rolling circle amplification (RCA).

    Science.gov (United States)

    Xiao, Meng; Guo, Li-Na; Kong, Fanrong; Wang, He; Sorrell, Tania C; Li, Ruo-Yu; Jiang, Wei; Chen, Sharon C-A; Xu, Ying-Chun

    2013-04-01

    We developed a reverse line blot (RLB) hybridization-, and rolling circle amplification (RCA)-based assays for the identification of Trichoporon species and evaluated them with 48 isolates that had been previously recognized as belonging to eight species (Trichosporon asahii, T. cutaneum, T. dermatis, T. domesticum, T. inkin, T. japonicum, T. jirovecii, and T. laibachii). Results were compared to those obtained with DNA sequencing of three rRNA gene loci, i.e., the internal transcribed spacer (ITS) region, D1/D2 domain of the 28S rRNA gene and intergenic spacer 1 (IGS1) region. Using species-specific, or group-specific probes targeted at the ITS region and the D1/D2 domain, the RLB assay permitted accurate species identification of all 48 isolates with 100% specificity. Species-specific RLB probes correctly assigned 45/48 (94%) of the isolates (six species) with the exception of T. dermatis and T. japonicum isolates which were not targeted by the assay. Identification of T. dermatis relied on a positive hybridization result with the group-specific probe hybridizing with T. dermatis and T. jirovecii and the absence of a signal with the T. jirovecii-specific probe. T. japonicum strains were first assigned to the T. asahii-T. japonicum group by hybridization with the two species group-specific probe and then as T. japonicum by the absence of signal with a T. asahii-specific probe. Twelve species-specific RCA probes targeting the eight species studied detected templates of all 48 Trichosporon isolates and an artificial template of T. asteroides, all with good specificity. Both RLB and RCA are potential alternatives to DNA sequencing for the identification of Trichosporon species. The RLB approach is suited for the batched simultaneous analysis of large numbers of isolates, while RCA is more appropriate for the immediate study of single isolates. Comparative costs are US$7 and US$2 per assay for the RLB and RCA methods, respectively.

  17. Do bees like Van Gogh's Sunflowers?

    Science.gov (United States)

    Chittka, Lars; Walker, Julian

    2006-06-01

    Flower colours have evolved over 100 million years to address the colour vision of their bee pollinators. In a much more rapid process, cultural (and horticultural) evolution has produced images of flowers that stimulate aesthetic responses in human observers. The colour vision and analysis of visual patterns differ in several respects between humans and bees. Here, a behavioural ecologist and an installation artist present bumblebees with reproductions of paintings highly appreciated in Western society, such as Van Gogh's Sunflowers. We use this unconventional approach in the hope to raise awareness for between-species differences in visual perception, and to provoke thinking about the implications of biology in human aesthetics and the relationship between object representation and its biological connotations.

  18. Genetic analysis of post-mating reproductive barriers in hybridizing European Populus species.

    Science.gov (United States)

    Macaya-Sanz, D; Suter, L; Joseph, J; Barbará, T; Alba, N; González-Martínez, S C; Widmer, A; Lexer, C

    2011-10-01

    Molecular genetic analyses of experimental crosses provide important information on the strength and nature of post-mating barriers to gene exchange between divergent populations, which are topics of great interest to evolutionary geneticists and breeders. Although not a trivial task in long-lived organisms such as trees, experimental interspecific recombinants can sometimes be created through controlled crosses involving natural F(1)'s. Here, we used this approach to understand the genetics of post-mating isolation and barriers to introgression in Populus alba and Populus tremula, two ecologically divergent, hybridizing forest trees. We studied 86 interspecific backcross (BC(1)) progeny and >350 individuals from natural populations of these species for up to 98 nuclear genetic markers, including microsatellites, indels and single nucleotide polymorphisms, and inferred the origin of the cytoplasm of the cross with plastid DNA. Genetic analysis of the BC(1) revealed extensive segregation distortions on six chromosomes, and >90% of these (12 out of 13) favored P. tremula donor alleles in the heterospecific genomic background. Since selection was documented during early diploid stages of the progeny, this surprising result was attributed to epistasis, cyto-nuclear coadaptation, heterozygote advantage at nuclear loci experiencing introgression or a combination of these. Our results indicate that gene flow across 'porous' species barriers affects these poplars and aspens beyond neutral, Mendelian expectations and suggests the mechanisms responsible. Contrary to expectations, the Populus sex determination region is not protected from introgression. Understanding the population dynamics of the Populus sex determination region will require tests based on natural interspecific hybrid zones.

  19. Four-year field experiment on nitrogen application to sunflower genotypes grown in semiarid conditions

    OpenAIRE

    De Giorgio D.; Montemurro V.; Fornaro F.

    2007-01-01

    A four-year field experiment was carried out to study the effects of different N levels on yield, yield components, N uptake and seed quality of sunflower genotypes grown in semiarid Mediterranean conditions. Five genotypes (four commercial hybrids and one newly selected genotype) and three N fertilization levels (0, 50 and 100 kg N ha-1) were compared over four years (1996, 1997, 1998 and 1999). Sunflower plants were taken at flowering time and their dry weight, leaf area index and total N c...

  20. Hybrid Collapse Confirms the Specific Status of Triatoma bahiensis Sherlock and Serafim, 1967 (Hemiptera, Triatominae), an Endemic Species in Brazil.

    Science.gov (United States)

    Chaboli Alevi, Kaio Cesar; Pinotti, Heloisa; Freitas de Araújo, Renato; Vilela de Azeredo Oliveira, Maria Tercília; Aristeu da Rosa, João; Mendonça, Vagner José

    2017-12-18

    Six to seven million people worldwide are estimated to be infected with Trypanosoma cruzi, the etiologic agent of Chagas disease transmitted mainly by triatomines. Triatoma bahiensis was recently collected in the Brazilian state of Bahia and revalidated using different approaches. The main criterion used to define a "good" biological species is reproductive isolation, so we evaluated the cytogenetics of first-generation (F1) hybrids resulting from the experimental cross between T. bahiensis females and Triatoma lenti males to possibly characterize the postzygotic isolation associated with the hybrid breakdown. All cells analyzed presented a karyotype of 2n = 22 and a pair of univalent autosomes. This chromosome behavior represents hybrid collapse and underscores the specific status of T. bahiensis. Thus, we have characterized the presence of the hybrid collapse phenomenon in an experimental cross, and we confirm the specific status of T. bahiensis, thus contributing to the Triatominae taxonomy.

  1. Validation of microsatellite multiplexes for parentage analysis and species discrimination in two hybridizing species of coral reef fish (Plectropomus spp., Serranidae)

    KAUST Repository

    Harrison, H.B.

    2014-04-24

    Microsatellites are often considered ideal markers to investigate ecological processes in animal populations. They are regularly used as genetic barcodes to identify species, individuals, and infer familial relationships. However, such applications are highly sensitive the number and diversity of microsatellite markers, which are also prone to error. Here, we propose a novel framework to assess the suitability of microsatellite datasets for parentage analysis and species discrimination in two closely related species of coral reef fish, Plectropomus leopardus and P. maculatus (Serranidae). Coral trout are important fisheries species throughout the Indo-Pacific region and have been shown to hybridize in parts of the Great Barrier Reef, Australia. We first describe the development of 25 microsatellite loci and their integration to three multiplex PCRs that co-amplify in both species. Using simulations, we demonstrate that the complete suite of markers provides appropriate power to discriminate between species, detect hybrid individuals, and resolve parent-offspring relationships in natural populations, with over 99.6% accuracy in parent-offspring assignments. The markers were also tested on seven additional species within the Plectropomus genus with polymorphism in 28-96% of loci. The multiplex PCRs developed here provide a reliable and cost-effective strategy to investigate evolutionary and ecological dynamics and will be broadly applicable in studies of wild populations and aquaculture brood stocks for these closely related fish species. 2014 The Authors. Ecology and Evolution published by John Wiley & Sons Ltd.

  2. Regeneration of interspecific somatic hybrids between Helianthus annuus L. and Helianthus maximiliani (Schrader) via protoplast electrofusion.

    Science.gov (United States)

    Taski-Ajdukovic, Ksenija; Vasic, Dragana; Nagl, Nevena

    2006-07-01

    Helianthus maximiliani is one of the wild Helianthus species with the genes for resistance to many pathogens including Sclerotinia sclerotiorum. Unfortunately, a transfer of disease resistance genes from this species into the cultivated sunflower is limited by its poor crossability with the cultivated sunflower and sterility of interspecific hybrids. To overcome this problem, mesophyll protoplasts of Sclerotinia sclerotiorum-resistant clone of H. maximiliani were electrically fused with etiolated hypocotyl protoplasts of the cultivated sunflower inbred line PH-BC1-91A. Fusion products were embedded in agarose droplets and subjected to different regeneration protocols. Developed microcalluses were released from the agarose and transferred into solid media. Shoot regeneration was achieved by culture of calluses on regeneration medium containing 2.2 mg l(-1) BAP and 0.01 mg l(-1) NAA after the treatment with a high concentration of 2,4 D for a limited period of time. A morphological and RAPD analysis confirmed a hybrid nature of the regenerated plants.

  3. Evaluation of hemlock (Tsuga) species and hybrids for resistance to Adelges tsugae (Hemiptera: Adelgidae) using artificial infestation

    Science.gov (United States)

    Michael E. Montgomery; S.E. Bentz; Richard T. Olsen

    2009-01-01

    Hemlock (Tsuga) species and hybrids were evaluated for resistance to the hemlock woolly adelgid, Adelges tsugae Annand (Hemiptera: Adelgidae). The adelgid was accidentally introduced from Asia to the eastern United States, where it is causing widespread mortality of the native hemlocks, Tsuga canadensis (L.)...

  4. Phytobenthos and phytoplankton community changes upon exposure to a sunflower oil spill in a South African protected freshwater wetland.

    Science.gov (United States)

    Oberholster, Paul J; Blaise, Christian; Botha, A-M

    2010-11-01

    The occurrence of a sunflower oil spill in 2007 in the Con Joubert Bird Sanctuary freshwater wetland, South Africa, inhibited the growth of sensitive phytoplankton species and promoted that of tolerant species. The algal divisions Chlorophyta and Euglenophyta were well represented in the sunflower oil contaminated water, especially the species Euglena sociabilis, Phacus pleuronectes and Chlamydomonas africana. Young and mature resting zygotes of Chlamydomonas africana were recorded in high abundance at all the sunflower oil contaminated sampling sites. The phytobenthos diversity and abundance were significantly suppressed and negatively associated with low Dissolved Oxygen concentrations and the negative redox potential of the bottom sediment. At the intracellular level, phytoplankton chlorophyll a and b concentrations as physiological variables were more sensitive indicators of the adverse effects of sunflower oil than the 72 h Selenastrum capricornutum algal bioassay conducted.

  5. Durability of resistance to rust in sunflower: Implications for resistance breeding

    Directory of Open Access Journals (Sweden)

    Llamas José María

    2010-01-01

    Full Text Available Sunflower rust is caused by Puccinia helianthi Schw. and is an important disease in Argentina, Australia, Canada, Egypt, Israel, Turkey, USA and the former USSR. Sunflower rust is a macrocyclic, heterothallic and autoecious fungus, surviving mainly in plant debris in soil in the form of teliospores. New races of P. helianthi are continuously evolving and overcoming resistance genes, resulting in a continuous threat for the crop. The deployment of hybrids with simple resistances has exacerbated this problem. Combination of the appropriate R-genes could result in a resistance more difficult to overcome. The identification and characterization of new durable sources of sunflower rust resistance is a high priority for both researchers and industry. There is a possibility of breeding for high coumarin content to improve resistance at early stages of fungal development.

  6. [Comparison of mitochondrial DNA in two greenling species and their hybrids (CEM. Hexagrammidae: Pisces) from Peter the Great Bay (Sea of Japan)].

    Science.gov (United States)

    Brykov, V A; Podlesnykh, A V

    2001-12-01

    Fragments of mtDNA from two greenling species, Hexagrammos octogrammus and H. agrammus, and their possible hybrids were amplified in PCR and examined using RFLP analysis. The inferred sequence difference between the species was 6.6%, which corresponds to about 3 Myr of their divergence. The reproductive contribution of males and females to the hybrids was estimated.

  7. Impact of abiotic stress on photosynthetic efficiency and leaf temperature in sunflower

    Directory of Open Access Journals (Sweden)

    Antonela Markulj Kulundžić

    2016-11-01

    Full Text Available The aim of this research was to investigate the variability of photosynthetic performance index (PIABS and leaf temperature values measured in V6 development phase on 13 sunflower hybrids, grown in stressful conditions. The pot trial was made up of two treatments, one (T1 with 60% Field Water Capacity (FWC, and the other one (T2 with 80% FWC. Significant differences between T1 and T2 treatments were established for both of these parameters which prove their dependence on the water content in the soil, while the influence of hybrid was evident only in the case of PIABS. Although in T1, as opposed to T2, all sunflower hybrids reacted by increasing leaf temperature, reaction to stress conditions measured with PIABS parameter was not uniform. Some of the hybrids reacted by decreasing PIABS values, while others reacted by increasing their PIABS values. Therefore, it can be concluded that changes in parameters were independent of each other, which was confirmed by correlation analysis. Investigated parameters are suitable for determining the existence of undesirable environmental conditions that cause stress in plants and can be used in breeding of sunflower to withstand abiotic stress conditions, i.e. in selection of stress tolerant hybrids.

  8. Effects of hybridization and evolutionary constraints on secondary metabolites: the genetic architecture of phenylpropanoids in European populus species.

    Directory of Open Access Journals (Sweden)

    Celine Caseys

    Full Text Available The mechanisms responsible for the origin, maintenance and evolution of plant secondary metabolite diversity remain largely unknown. Decades of phenotypic studies suggest hybridization as a key player in generating chemical diversity in plants. Knowledge of the genetic architecture and selective constraints of phytochemical traits is key to understanding the effects of hybridization on plant chemical diversity and ecological interactions. Using the European Populus species P. alba (White poplar and P. tremula (European aspen and their hybrids as a model, we examined levels of inter- and intraspecific variation, heritabilities, phenotypic correlations, and the genetic architecture of 38 compounds of the phenylpropanoid pathway measured by liquid chromatography and mass spectrometry (UHPLC-MS. We detected 41 quantitative trait loci (QTL for chlorogenic acids, salicinoids and flavonoids by genetic mapping in natural hybrid crosses. We show that these three branches of the phenylpropanoid pathway exhibit different geographic patterns of variation, heritabilities, and genetic architectures, and that they are affected differently by hybridization and evolutionary constraints. Flavonoid abundances present high species specificity, clear geographic structure, and strong genetic determination, contrary to salicinoids and chlorogenic acids. Salicinoids, which represent important defence compounds in Salicaceae, exhibited pronounced genetic correlations on the QTL map. Our results suggest that interspecific phytochemical differentiation is concentrated in downstream sections of the phenylpropanoid pathway. In particular, our data point to glycosyltransferase enzymes as likely targets of rapid evolution and interspecific differentiation in the 'model forest tree' Populus.

  9. Effects of Hybridization and Evolutionary Constraints on Secondary Metabolites: The Genetic Architecture of Phenylpropanoids in European Populus Species

    Science.gov (United States)

    Caseys, Celine; Stritt, Christoph; Glauser, Gaetan; Blanchard, Thierry; Lexer, Christian

    2015-01-01

    The mechanisms responsible for the origin, maintenance and evolution of plant secondary metabolite diversity remain largely unknown. Decades of phenotypic studies suggest hybridization as a key player in generating chemical diversity in plants. Knowledge of the genetic architecture and selective constraints of phytochemical traits is key to understanding the effects of hybridization on plant chemical diversity and ecological interactions. Using the European Populus species P. alba (White poplar) and P. tremula (European aspen) and their hybrids as a model, we examined levels of inter- and intraspecific variation, heritabilities, phenotypic correlations, and the genetic architecture of 38 compounds of the phenylpropanoid pathway measured by liquid chromatography and mass spectrometry (UHPLC-MS). We detected 41 quantitative trait loci (QTL) for chlorogenic acids, salicinoids and flavonoids by genetic mapping in natural hybrid crosses. We show that these three branches of the phenylpropanoid pathway exhibit different geographic patterns of variation, heritabilities, and genetic architectures, and that they are affected differently by hybridization and evolutionary constraints. Flavonoid abundances present high species specificity, clear geographic structure, and strong genetic determination, contrary to salicinoids and chlorogenic acids. Salicinoids, which represent important defence compounds in Salicaceae, exhibited pronounced genetic correlations on the QTL map. Our results suggest that interspecific phytochemical differentiation is concentrated in downstream sections of the phenylpropanoid pathway. In particular, our data point to glycosyltransferase enzymes as likely targets of rapid evolution and interspecific differentiation in the ‘model forest tree’ Populus. PMID:26010156

  10. Potential Hybridization between Two Invasive Termite Species, Coptotermes formosanus and C. gestroi (Isoptera: Rhinotermitidae, and Its Biological and Economic Implications

    Directory of Open Access Journals (Sweden)

    Nan-Yao Su

    2017-01-01

    Full Text Available The Asian subterranean termite, Coptotermes gestroi, is a tropical species but has increasingly been collected from the subtropics in recent years, making it sympatric to the Formosan subterranean termite, C. formosanus in at least three areas, Taiwan, Hawaii, and Florida. Simultaneous flights by these two species were observed since 2013 in South Florida, during which interspecies tandems were observed. Laboratory mating of C. formosanus and C. gestroi alates produced hybrid incipient colonies of larger population size. Studies are underway to examine the presence in the field of hybrid colonies in sympatric areas of Taiwan and Florida. Other biological characteristics of C. formosanus × C. gestroi hybrids being studied include temperature tolerance and preference, colony growth rate, wood-consumption rate, and reproductive fertility. This current research aims to determine the potential establishment of a hybrid termite population in south Florida and Taiwan. It investigates the risk of introgressive hybridization in field populations, with an emphasis on its potential ecological, evolutionary, and economic consequences.

  11. Effects of hybridization and evolutionary constraints on secondary metabolites: the genetic architecture of phenylpropanoids in European populus species.

    Science.gov (United States)

    Caseys, Celine; Stritt, Christoph; Glauser, Gaetan; Blanchard, Thierry; Lexer, Christian

    2015-01-01

    The mechanisms responsible for the origin, maintenance and evolution of plant secondary metabolite diversity remain largely unknown. Decades of phenotypic studies suggest hybridization as a key player in generating chemical diversity in plants. Knowledge of the genetic architecture and selective constraints of phytochemical traits is key to understanding the effects of hybridization on plant chemical diversity and ecological interactions. Using the European Populus species P. alba (White poplar) and P. tremula (European aspen) and their hybrids as a model, we examined levels of inter- and intraspecific variation, heritabilities, phenotypic correlations, and the genetic architecture of 38 compounds of the phenylpropanoid pathway measured by liquid chromatography and mass spectrometry (UHPLC-MS). We detected 41 quantitative trait loci (QTL) for chlorogenic acids, salicinoids and flavonoids by genetic mapping in natural hybrid crosses. We show that these three branches of the phenylpropanoid pathway exhibit different geographic patterns of variation, heritabilities, and genetic architectures, and that they are affected differently by hybridization and evolutionary constraints. Flavonoid abundances present high species specificity, clear geographic structure, and strong genetic determination, contrary to salicinoids and chlorogenic acids. Salicinoids, which represent important defence compounds in Salicaceae, exhibited pronounced genetic correlations on the QTL map. Our results suggest that interspecific phytochemical differentiation is concentrated in downstream sections of the phenylpropanoid pathway. In particular, our data point to glycosyltransferase enzymes as likely targets of rapid evolution and interspecific differentiation in the 'model forest tree' Populus.

  12. Alterations in cytosine methylation and species-specific transcription induced by interspecific hybridization between Oryza sativa and O. officinalis.

    Science.gov (United States)

    Jin, Huajun; Hu, Wei; Wei, Zhe; Wan, Linglin; Li, Gang; Tan, Guangxuan; Zhu, Lili; He, Guangcun

    2008-11-01

    Interspecific hybridization and polyploidization may involve programmed genetic and epigenetic changes. In this study, we used the methylation-sensitive amplified polymorphism (MSAP) method to survey cytosine methylation alterations that occurred in F(1) hybrid and BC(1) progeny following interspecific hybridization between Oryza sativa and O. officinalis. Across all 316 parental methylated sites, 25 (7.9%) cytosine methylation alterations were detected in the F(1) and/or BC(1) progeny. Thirty additional cytosine methylation alterations were detected at parental non-methylated or novel sites. In total, 55 cytosine methylation alterations (90.9% of all alterations) were detected in the F(1) hybrid, which were maintained in the BC(1) progeny. The alterations in cytosine methylation were biased toward the O. officinalis parent and were in some cases repeatable in independent hybridizations between O. sativa and O. officinalis. Twelve fragments showing cytosine methylation alterations were isolated, sequenced and subsequently validated by methylation-sensitive Southern blot analysis. Where possible, we designed species-specific primers to amplify the polymorphic transcripts from either the O. sativa or the O. officinalis parent using reverse transcription (RT)-PCR in combination with single-strand conformation polymorphism (SSCP) analysis. In four of five cases, modified gene expression could be correlated with the altered cytosine methylation pattern. Our results demonstrated cytosine methylation alterations induced by interspecific hybridization between a rice cultivar and its wild relative, and indicated a direct relationship between cytosine methylation alteration and gene expression variation.

  13. Transcriptome-wide signature of hybrid breakdown associated with intrinsic reproductive isolation in lake whitefish species pairs (Coregonus spp. Salmonidae).

    Science.gov (United States)

    Renaut, S; Bernatchez, L

    2011-06-01

    Genetic analyses of speciation have focused nearly exclusively on retrospective analyses of reproductive isolation between highly divergent species. Yet, a full understanding of the speciation process must encompass analysis of the consequences of genomic divergence in young lineages still capable of exchanging genes under natural conditions. The accumulation of conditionally neutral genetic variation may lead to the evolution of divergent gene networks. In a hybrid background, such mutations may no longer compensate one another, resulting in the appearance of selectively disadvantageous traits, including disruption of gene expression regulation. Here, we documented genome-wide patterns of gene expression divergence between young lineages of normal and dwarf lake whitefish and their backcross hybrids for which strong, yet incomplete post-zygotic isolation barriers exist. A significant proportion (33%) of backcross hybrids showed developmental abnormalities not seen in parental forms and eventually leading to death. Although the transcriptome of parental forms was nearly identical during embryonic development, suggesting a role for stabilizing selection, all hybrids displayed strongly divergent patterns of gene expression. By comparing healthy, surviving hybrids against moribund ones showing abnormal development, we observed that over 2000 genes were misregulated in these abnormal embryos. In particular, misregulation was significantly biased toward essential developmental genes, which were severely underexpressed. Furthermore, genes previously documented to be highly transgressive (exaggerated inter-individual variance) were almost invariably underexpressed in hybrids. Our results thus clearly showed a transcriptome-wide signature of hybrid breakdown in young, incipient species and demonstrated a persuasive link between misexpression of essential developmental genes and post-zygotic isolation.

  14. Assessing the prevalence of hybridization between sympatric Canis species surrounding the red wolf (Canis rufus) recovery area in North Carolina.

    Science.gov (United States)

    Bohling, Justin H; Waits, Lisette P

    2011-05-01

    Predicting spatial patterns of hybridization is important for evolutionary and conservation biology yet are hampered by poor understanding of how hybridizing species can interact. This is especially pertinent in contact zones where hybridizing populations are sympatric. In this study, we examined the extent of red wolf (Canis rufus) colonization and introgression where the species contacts a coyote (C. latrans) population in North Carolina, USA. We surveyed 22,000km(2) in the winter of 2008 for scat and identified individual canids through genetic analysis. Of 614 collected scats, 250 were assigned to canids by mitochondrial DNA (mtDNA) sequencing. Canid samples were genotyped at 6-17 microsatellite loci (nDNA) and assigned to species using three admixture criteria implemented in two Bayesian clustering programs. We genotyped 82 individuals but none were identified as red wolves. Two individuals had red wolf mtDNA but no significant red wolf nDNA ancestry. One individual possessed significant red wolf nDNA ancestry (approximately 30%) using all criteria, although seven other individuals showed evidence of red wolf ancestry (11-21%) using the relaxed criterion. Overall, seven individuals were classified as hybrids using the conservative criteria and 37 using the relaxed criterion. We found evidence of dog (C. familiaris) and gray wolf (C. lupus) introgression into the coyote population. We compared the performance of different methods and criteria by analyzing known red wolves and hybrids. These results suggest that red wolf colonization and introgression in North Carolina is minimal and provide insights into the utility of Bayesian clustering methods to detect hybridization. © 2011 Blackwell Publishing Ltd.

  15. North African hybrid sparrows (Passer domesticus, P. hispaniolensis) back from oblivion - ecological segregation and asymmetric mitochondrial introgression between parental species.

    Science.gov (United States)

    Ait Belkacem, Abdelkrim; Gast, Oliver; Stuckas, Heiko; Canal, David; LoValvo, Mario; Giacalone, Gabriele; Päckert, Martin

    2016-08-01

    A stabilized hybrid form of the house sparrow (Passer domesticus) and the Spanish sparrow (P. hispaniolensis) is known as Passer italiae from the Italian Peninsula and a few Mediterranean islands. The growing attention for the Italian hybrid sparrow and increasing knowledge on its biology and genetic constitution greatly contrast the complete lack of knowledge of the long-known phenotypical hybrid sparrow populations from North Africa. Our study provides new data on the breeding biology and variation of mitochondrial DNA in three Algerian populations of house sparrows, Spanish sparrows, and phenotypical hybrids. In two field seasons, the two species occupied different breeding habitats: Spanish sparrows were only found in rural areas outside the cities and bred in open-cup nests built in large jujube bushes. In contrast, house sparrows bred only in the town centers and occupied nesting holes in walls of buildings. Phenotypical hybrids were always associated with house sparrow populations. House sparrows and phenotypical hybrids started breeding mid of March, and most pairs had three successive clutches, whereas Spanish sparrows started breeding almost one month later and had only two successive clutches. Mitochondrial introgression is strongly asymmetric because about 75% of the rural Spanish sparrow population carried house sparrow haplotypes. In contrast, populations of the Italian hybrid form, P. italiae, were genetically least diverse among all study populations and showed a near-fixation of house sparrow haplotypes that elsewhere were extremely rare or that were even unique for the Italian Peninsula. Such differences between mitochondrial gene pools of Italian and North African hybrid sparrow populations provide first evidence that different demographic histories have shaped the extant genetic diversity observed on both continents.

  16. Development and Testing of Cool-Season Grass Species, Varieties and Hybrids for Biomass Feedstock Production in Western North America

    Directory of Open Access Journals (Sweden)

    Steven R. Larson

    2017-01-01

    Full Text Available Breeding of native cool-season grasses has the potential to improve forage production and expand the range of bioenergy feedstocks throughout western North America. Basin wildrye (Leymus cinereus and creeping wildrye (Leymus triticoides rank among the tallest and most rhizomatous grasses of this region, respectively. The objectives of this study were to develop interspecific creeping wildrye (CWR × basin wildrye (BWR hybrids and evaluate their biomass yield relative to tetraploid ‘Trailhead’, octoploid ‘Magnar’ and interploidy-hybrid ‘Continental’ BWR cultivars in comparison with other perennial grasses across diverse single-harvest dryland range sites and a two-harvest irrigated production system. Two half-sib hybrid populations were produced by harvesting seed from the tetraploid self-incompatible Acc:641.T CWR genet, which was clonally propagated by rhizomes into isolated hybridization blocks with two tetraploid BWR pollen parents: Acc:636 and ‘Trailhead’. Full-sib hybrid seed was also produced from a controlled cross of tetraploid ‘Rio’ CWR and ‘Trailhead’ BWR plants. In space-planted range plots, the ‘Rio’ CWR × ‘Trailhead’ BWR and Acc:641.T CWR × Acc:636 BWR hybrids displayed high-parent heterosis with 75% and 36% yield advantages, respectively, but the Acc:641.T CWR × ‘Trailhead’ BWR hybrid yielded significantly less than its BWR high-parent in this evaluation. Half-sib CWR × BWR hybrids of Acc:636 and ‘Trailhead’ both yielded as good as or better than available BWR cultivars, with yields similar to switchgrass (Panicum virgatum, in the irrigated sward plots. These results elucidate opportunity to harness genetic variation among native grass species for the development of forage and bioenergy feedstocks in western North America.

  17. Transcriptome analysis in non-model species: a new method for the analysis of heterologous hybridization on microarrays

    Directory of Open Access Journals (Sweden)

    Jouventin Pierre

    2010-05-01

    Full Text Available Abstract Background Recent developments in high-throughput methods of analyzing transcriptomic profiles are promising for many areas of biology, including ecophysiology. However, although commercial microarrays are available for most common laboratory models, transcriptome analysis in non-traditional model species still remains a challenge. Indeed, the signal resulting from heterologous hybridization is low and difficult to interpret because of the weak complementarity between probe and target sequences, especially when no microarray dedicated to a genetically close species is available. Results We show here that transcriptome analysis in a species genetically distant from laboratory models is made possible by using MAXRS, a new method of analyzing heterologous hybridization on microarrays. This method takes advantage of the design of several commercial microarrays, with different probes targeting the same transcript. To illustrate and test this method, we analyzed the transcriptome of king penguin pectoralis muscle hybridized to Affymetrix chicken microarrays, two organisms separated by an evolutionary distance of approximately 100 million years. The differential gene expression observed between different physiological situations computed by MAXRS was confirmed by real-time PCR on 10 genes out of 11 tested. Conclusions MAXRS appears to be an appropriate method for gene expression analysis under heterologous hybridization conditions.

  18. Transcriptome analysis in non-model species: a new method for the analysis of heterologous hybridization on microarrays.

    Science.gov (United States)

    Degletagne, Cyril; Keime, Céline; Rey, Benjamin; de Dinechin, Marc; Forcheron, Fabien; Chuchana, Paul; Jouventin, Pierre; Gautier, Christian; Duchamp, Claude

    2010-05-31

    Recent developments in high-throughput methods of analyzing transcriptomic profiles are promising for many areas of biology, including ecophysiology. However, although commercial microarrays are available for most common laboratory models, transcriptome analysis in non-traditional model species still remains a challenge. Indeed, the signal resulting from heterologous hybridization is low and difficult to interpret because of the weak complementarity between probe and target sequences, especially when no microarray dedicated to a genetically close species is available. We show here that transcriptome analysis in a species genetically distant from laboratory models is made possible by using MAXRS, a new method of analyzing heterologous hybridization on microarrays. This method takes advantage of the design of several commercial microarrays, with different probes targeting the same transcript. To illustrate and test this method, we analyzed the transcriptome of king penguin pectoralis muscle hybridized to Affymetrix chicken microarrays, two organisms separated by an evolutionary distance of approximately 100 million years. The differential gene expression observed between different physiological situations computed by MAXRS was confirmed by real-time PCR on 10 genes out of 11 tested. MAXRS appears to be an appropriate method for gene expression analysis under heterologous hybridization conditions.

  19. Genetic Evidence of Hybridization between the Endangered Native Species Iguana delicatissima and the Invasive Iguana iguana (Reptilia, Iguanidae in the Lesser Antilles: Management Implications.

    Directory of Open Access Journals (Sweden)

    Barbara Vuillaume

    Full Text Available The worldwide increase of hybridization in different groups is thought to have become more important with the loss of isolating barriers and the introduction of invasive species. This phenomenon could result in the extinction of endemic species. This study aims at investigating the hybridization dynamics between the endemic and threatened Lesser Antillean iguana (Iguana delicatissima and the invasive common green iguana (Iguana iguana in the Lesser Antilles, as well as assessing the impact of interspecific hybridization on the decline of I. delicatissima. 59 I. delicatissima (5 localities, 47 I. iguana (12 localities and 27 hybrids (5 localities, who were all identified based on morphological characters, have been genotyped at 15 microsatellites markers. We also sequenced hybrids using ND4 mitochondrial loci to further investigate mitochondrial introgression. The genetic clustering of species and hybrid genetic assignment were performed using a comparative approach, through the implementation of a Discriminant Analysis of Principal Component (DAPC based on statistics, as well as genetic clustering approaches based on the genetic models of several populations (Structure, NewHybrids and HIest, in order to get full characterization of hybridization patterns and introgression dynamics across the islands. The iguanas identified as hybrids in the wild, thanks to morphological analysis, were all genetically F1, F2, or backcrosses. A high proportion of individuals were also the result of a longer-term admixture. The absence of reproductive barriers between species leads to hybridization when species are in contact. Yet morphological and behavioral differences between species could explain why males I. iguana may dominate I. delicatissima, thus resulting in short-term species displacement and extinction by hybridization and recurrent introgression from I. iguana toward I. delicatissima. As a consequence, I. delicatissima gets eliminated through

  20. Genetic Evidence of Hybridization between the Endangered Native Species Iguana delicatissima and the Invasive Iguana iguana (Reptilia, Iguanidae) in the Lesser Antilles: Management Implications.

    Science.gov (United States)

    Vuillaume, Barbara; Valette, Victorien; Lepais, Olivier; Grandjean, Frédéric; Breuil, Michel

    2015-01-01

    The worldwide increase of hybridization in different groups is thought to have become more important with the loss of isolating barriers and the introduction of invasive species. This phenomenon could result in the extinction of endemic species. This study aims at investigating the hybridization dynamics between the endemic and threatened Lesser Antillean iguana (Iguana delicatissima) and the invasive common green iguana (Iguana iguana) in the Lesser Antilles, as well as assessing the impact of interspecific hybridization on the decline of I. delicatissima. 59 I. delicatissima (5 localities), 47 I. iguana (12 localities) and 27 hybrids (5 localities), who were all identified based on morphological characters, have been genotyped at 15 microsatellites markers. We also sequenced hybrids using ND4 mitochondrial loci to further investigate mitochondrial introgression. The genetic clustering of species and hybrid genetic assignment were performed using a comparative approach, through the implementation of a Discriminant Analysis of Principal Component (DAPC) based on statistics, as well as genetic clustering approaches based on the genetic models of several populations (Structure, NewHybrids and HIest), in order to get full characterization of hybridization patterns and introgression dynamics across the islands. The iguanas identified as hybrids in the wild, thanks to morphological analysis, were all genetically F1, F2, or backcrosses. A high proportion of individuals were also the result of a longer-term admixture. The absence of reproductive barriers between species leads to hybridization when species are in contact. Yet morphological and behavioral differences between species could explain why males I. iguana may dominate I. delicatissima, thus resulting in short-term species displacement and extinction by hybridization and recurrent introgression from I. iguana toward I. delicatissima. As a consequence, I. delicatissima gets eliminated through introgression, as

  1. 7 CFR 457.108 - Sunflower seed crop insurance provisions.

    Science.gov (United States)

    2010-01-01

    ... Crop Provisions If a conflict exists among the policy provisions, the order of priority is as follows... for oil type sunflower seed grading U.S. No. 2, or non-oil type sunflower seed with a test weight of... area in which you normally market the sunflower seed. The local market price for oil type sunflower...

  2. Gene flow and hybridization between numerically imbalanced populations of two duck species on the subantarctic island of South Georgia.

    Directory of Open Access Journals (Sweden)

    Kevin G McCracken

    Full Text Available Hybridization is common between species of animals, particularly in waterfowl (Anatidae. One factor shown to promote hybridization is restricted mate choice, which can occur when 2 species occur in sympatry but one is rare. According to the Hubbs principle, or "desperation hypothesis," the rarer species is more likely to mate with heterospecifics. We report the second of 2 independent examples of hybridization between 2 species of ducks inhabiting island ecosystems in the Subantarctic and South Atlantic Ocean. Yellow-billed pintails (Anas georgica and speckled teal (Anas flavirostris are abundant in continental South America, where they are sympatric and coexist in mixed flocks. But on South Georgia, an isolated island in the Subantarctic, the pintail population of approximately 6000 pairs outnumbers a small breeding population of speckled teal 300∶1. Using 6 genetic loci (mtDNA and 5 nuclear introns and Bayesian assignment tests coupled with coalescent analyses, we identified hybrid-origin speckled teal alleles in 2 pintails on South Georgia. While it is unclear whether introgression has also occurred into the speckled teal population, our data suggest that this hybridization was not a recent event, but occurred some time ago. We also failed to identify unequivocal evidence of introgression in a much larger sample of pintails and speckled teal from Argentina using a 3-population "Isolation-with-Migration" coalescent analysis. Combined with parallel findings of hybridization between these same 2 duck species in the Falkland Islands, where population ratios are reversed and pintails are outnumbered by speckled teal 1:10, our results provide further support for the desperation hypothesis, which predicts that scarcity in one population and abundance of another will often lead to hybridization. While the South Georgia pintail population appears to be thriving, it's possible that low density of conspecific mates and inverse density dependence

  3. Chemicals involved in honeybee-sunflower relationship.

    Science.gov (United States)

    Pham-Delegue, M H; Etievant, P; Guichard, E; Marilleau, R; Douault, P; Chauffaille, J; Masson, C

    1990-11-01

    We present a review of work on the plant chemicals involved in the honeybee-sunflower model system. Combined behavioral and chemical analyses were conducted under natural and controlled conditions. First the distribution of forager bees' visits on two pairs of sunflower genotypes producing a different level of hybrid seed yield was recorded under pollen-proof tunnels. Mirasol parental lines producing high seed yields were visited at random, whereas forager bees visited preferentially the female parental line of Marianne, resulting in low seed yield. Nectar samples collected on the genotypes were analyzed by gas chromatography. Fructose, glucose, and sucrose were identified. Parental lines of Mirasol showed similar sugar profiles, whereas the female line of Marianne contained higher amounts of sucrose than the male line. We assume that the bees' preferences between genotypes might rely on differences in the sugar composition of floral nectars, especially in the amount of sucrose. Aromas from headspace collection were compared between pairs and periodically during the flowering period. Of the 144 components indexed for Marianne lines and 136 components for Mirasol lines, 17 of the components for Marianne lines and 18 for Mirasol lines differed significantly according to flowering stage. Significant differences appeared in eight of the 134 components of Marianne lines and in 20 of the 250 components for Mirasol lines. Such differences, even restricted to a few components, might account for honeybees' discrimination between genotypes or flowering stage. Experiments then were conducted in a flight room using an artificial flower device. A total volatile extract was used as a conditioning scent previous to the test where the total extract was successively compared to several of its subfractions. Fractions significantly less visited than the total extract were discarded, whereas fractions confused with the total extract were kept. From step to step, a restricted fraction

  4. Hybrid asexuality as a primary postzygotic barrier between nascent species: on the interconnection between asexuality, hybridization and speciation

    Czech Academy of Sciences Publication Activity Database

    Janko, K.; Pačes, J.; Wilkinson-Herbots, H.; Costa, R. J.; Roslein, Jan; Drozd, P.; Iakovenko, N.; Rídl, J.; Hroudová, M.; Kočí, J.; Reifová, R.; Šlechtová, V.; Choleva, L.

    2018-01-01

    Roč. 27, č. 1 (2018), s. 248-263 ISSN 0962-1083 R&D Projects: GA ČR(CZ) GBP505/12/G112; GA ČR GA13-12580S Institutional support: RVO:68081766 Keywords : pairwise nucleotide differences * mitochondrial-dna variation * multilocus genotype data * reproductive isolation * maximum-likelihood * loaches cobitis * migration model * gene flow * phylogenetic constraints * coalescence time * balance hypothesis * coalescence * evolution of asexuality * hybridization * phylogeography * speciation Subject RIV: EG - Zoology Impact factor: 6.086, year: 2016

  5. Comparative pulping of sunflower stalks

    Directory of Open Access Journals (Sweden)

    Valerii Barbash

    2016-03-01

    Full Text Available The procedure of holocellulose content determination in non-wood plant raw materials was developed. The strength properties of pulp obtained from sunflower stalks by neutral-sulphite, soda, alkaline sulphite-anthraquinone-ethanol and peracetic methods of delignification were studied. Methodology of comparison of plant materials delignification methods using new lignin-carbohydrate diagram was proposed. It was shown, that the alkaline sulphite-anthraquinone-ethanol method of pulping is characterized by the highest delignification degree and is the most efficient among the studied methods

  6. Interspecific hybridization and bioactive alkaloid variation increases diversity in endophytic Epichloë species of Bromus laevipes.

    Science.gov (United States)

    Charlton, Nikki D; Craven, Kelly D; Afkhami, Michelle E; Hall, Bradley A; Ghimire, Sita R; Young, Carolyn A

    2014-10-01

    Studying geographic variation of microbial mutualists, especially variation in traits related to benefits they provide their host, is critical for understanding how these associations impact key ecological processes. In this study, we investigate the phylogenetic population structure of Epichloë species within Bromus laevipes, a native cool-season bunchgrass found predominantly in California. Phylogenetic classification supported inference of three distinct Epichloë taxa, of which one was nonhybrid and two were interspecific hybrids. Inheritance of mating-type idiomorphs revealed that at least one of the hybrid species arose from independent hybridization events. We further investigated the geographic variation of endophyte-encoded alkaloid genes, which is often associated with key benefits of natural enemy protection for the host. Marker diversity at the ergot alkaloid, loline, indole-diterpene, and peramine loci revealed four alkaloid genotypes across the three identified Epichloë species. Predicted chemotypes were tested using endophyte-infected plant material that represented each endophyte genotype, and 11 of the 13 predicted alkaloids were confirmed. This multifaceted approach combining phylogenetic, genotypic, and chemotypic analyses allowed us to reconstruct the diverse evolutionary histories of Epichloë species present within B. laevipes and highlight the complex and dynamic processes underlying these grass-endophyte symbioses. © 2014 Federation of European Microbiological Societies. Published by John Wiley & Sons Ltd. All rights reserved.

  7. Comparative Pollen Morphological Analysis and Its Systematic Implications on Three European Oak (Quercus L., Fagaceae) Species and Their Spontaneous Hybrids.

    Science.gov (United States)

    Wrońska-Pilarek, Dorota; Danielewicz, Władysław; Bocianowski, Jan; Maliński, Tomasz; Janyszek, Magdalena

    2016-01-01

    Pollen morphology of three parental Quercus species (Q. robur L., Q. petraea (Matt) Liebl, Q. pubescens Willd.) and two spontaneous hybrids of these species (Q. ×calvescens Vuk. = Q. petraea × Q. pubescens and Q. ×rosacea Bechst. = Q. robur × Q. petraea) was investigated in this study. The pollen originated from 18 natural oak sites and 67 individuals (oak trees). Each individual was represented by 30 pollen grains. In total, 2010 pollen grains were measured. They were analysed for nine quantitative and four qualitative features. Pollen size and shape were important features to diagnosing Quercus parental species and hybrids. On the basis of exine ornamentation, it was possible to identify only Q. pubescens, while the remaining species and hybrids did not differ significantly with respect to this feature. The determination of the diagnostic value of endoaperture features requires further palynological studies. On the basis of pollen size and shape Q. robur × Q. petraea was clearly separated. Grouping of 67 oak trees on the basis of pollen grain features has shown that individuals from different as well as same taxa occurred in the same groups. Likewise, with respect to natural sites, oak trees originating from the same places as well as from geographically distant ones, grouped together. Pollen morphological features allow to distinguish a part of the studied Quercus taxa. Therefore, it can be used as an auxiliary feature in the taxonomy.

  8. Comparative Pollen Morphological Analysis and Its Systematic Implications on Three European Oak (Quercus L., Fagaceae Species and Their Spontaneous Hybrids.

    Directory of Open Access Journals (Sweden)

    Dorota Wrońska-Pilarek

    Full Text Available Pollen morphology of three parental Quercus species (Q. robur L., Q. petraea (Matt Liebl, Q. pubescens Willd. and two spontaneous hybrids of these species (Q. ×calvescens Vuk. = Q. petraea × Q. pubescens and Q. ×rosacea Bechst. = Q. robur × Q. petraea was investigated in this study. The pollen originated from 18 natural oak sites and 67 individuals (oak trees. Each individual was represented by 30 pollen grains. In total, 2010 pollen grains were measured. They were analysed for nine quantitative and four qualitative features. Pollen size and shape were important features to diagnosing Quercus parental species and hybrids. On the basis of exine ornamentation, it was possible to identify only Q. pubescens, while the remaining species and hybrids did not differ significantly with respect to this feature. The determination of the diagnostic value of endoaperture features requires further palynological studies. On the basis of pollen size and shape Q. robur × Q. petraea was clearly separated. Grouping of 67 oak trees on the basis of pollen grain features has shown that individuals from different as well as same taxa occurred in the same groups. Likewise, with respect to natural sites, oak trees originating from the same places as well as from geographically distant ones, grouped together. Pollen morphological features allow to distinguish a part of the studied Quercus taxa. Therefore, it can be used as an auxiliary feature in the taxonomy.

  9. Molecular evidence for the hybrid origin of species in the soft coral genus Alcyonium (Cnidaria: Anthozoa: Octocorallia).

    Science.gov (United States)

    McFadden, Catherine S; Hutchinson, M Breton

    2004-06-01

    Several recent studies have suggested that hybridization may play a previously unrecognized and important role in the evolution of corals. Our observations of polymorphic and recombinant sequences in the multicopy ribosomal internal transcribed spacer (ITS) region suggested the possible hybrid origin of two European soft coral species, Alcyonium hibernicum and Bellonella bocagei. To examine this possibility further we cloned and sequenced ITS-1 from multiple individuals and populations of these two species as well as two sympatric congeners, A. coralloides and A. sp. M2. Phylogenetic analyses separated the observed sequence variants into two distinct clades. All A. coralloides sequences belonged to clade A, while A. sp. M2 had only clade B sequences. A majority of A. hibernicum individuals, however, contained both clade A and B sequences that were identical to the predominant sequence variants found in A. coralloides and A. sp. M2, respectively. This pattern of additivity suggests that A. hibernicum originated from a hybrid cross between A. coralloides and A. sp. M2, a hypothesis that is supported by its unusual mode of reproduction (meiotic parthenogenesis). The predominant sequence variant found in B. bocagei was a unique, derived clade B sequence; in addition, however, most individuals of this species also had copies of a sequence identified as a recombinant between clade A and clade B sequence types. The presence of this recombinant sequence in the B. bocagei genome suggests that this species may also be the product of past hybridization events within the clade. Reticulate evolution may explain the failure of several previous studies to resolve the phylogeny of these four species.

  10. Maize, Sunflower and Barley Sensitivity to the Residual Activity of Clomazone in Soil

    Directory of Open Access Journals (Sweden)

    Jelena Gajić Umiljendić

    2012-01-01

    Full Text Available Sensitivity of maize, sunflower and barley to clomazone residues in loamy soil wasassessed in the study using bioassay. Clomazone was applied at a series of concentrationsfrom 0.12 to 12 mg a.i./kg of soil. After 14 days, morphological (shoot height, fresh and dryweight and physiological (content of carotenoids, chlorophyll a and chlorophyll b parameterswere measured. The results showed that morphological parameters are not valid indicatorsof clomazone sensitivity. Based on the results showing inhibition of the physiologicalparameters, I50 values were calculated and used to estimate the difference in sensitivitybetween the species tested. Sunflower was the most sensitive species, while the differencein sensitivity between maize and barley was not significant.Nomenclature: clomazone (2-(2-chlorbenzyl-4,4-dimethyl-1,2-oxazolidin-3-one, maize(Zea mays L., sunflower (Helianthus annuus L., barley (Hordeum vulgare L.

  11. Evaluation of Various Hybrid Analytical Techniques for Resolving Arsenic Species in Soils and Natural Waters from Korea

    Science.gov (United States)

    Kim, Y.; Yoon, H.; Shin, M.; Yoon, C.; Woo, N.

    2005-12-01

    The importance of arsenic detection in terms of different chemical species is becoming nowadays environmental concern. The analytical technique for true separation of different arsenic species has been challenging in many environmental samples. Achieving correct analytical results and resolving the lowest detection limit of each species is also desirable. However arsenic species can be transformed rapidly by slight changes in redox condition during experimental manipulation. It has been documented by USEPA for standard analytical technique for arsenic from many samples. However the previously documented techniques concerns only total arsenic concentration. Many analytical techniques for analyzing arsenic species are being suggested and hybrid analytical technique is regarded as essential method to resolve arsenic species. In this study, various hybrid techniques using ICP were tested to separate arsenic species in different type of samples. The anion exchange cartridge (Accell Plus QMA, Waters) or column (PRP X-100, Hamilton) in the part for separation and (HG)-ICP-AES or (HG)-ICP-MS in the part for detection coupled. Hydride generation (HG) method is used to improve detection limits. In addition, it can prevent from interference of 75 ArCl which is a significant problem of ICP-MS application to arsenic analysis. Anion exchange cartridge is only applicable in separation of inorganic arsenic species, typically available to acid mine drainage and groundwater samples in which arsenic mainly exists inorganic form. LC-(HG)-ICP-MS techenique is profitable to natural surface water samples which have a small fraction of various arsenic species. The leachate from soil samples should be treated carefully because high content of transition metals cause interferences. If there were a probability of leaching considerable amount of organic matter and transition metals during soil extraction, HG technique with purification procedure and use of masking agent must be applied to

  12. Electrical Properties of Sunflower Achenes

    Directory of Open Access Journals (Sweden)

    Novák Ján

    2014-12-01

    Full Text Available This work contains the results of measuring the electrical properties of sunflower achenes. The interest in electrical properties of biological materials resulted in engineering research in this field. The results of measurements are used for determining the moisture content, the surface level of liquid and grainy materials, for controlling the presence of pests in grain storage, for the quantitative determination of mechanical damage, in the application of dielectric heating, and in many other areas. Electrical measurements of these materials are of fundamental importance in relation to the analysis of quantity of absorbed water and dielectric heating characteristics. It is a well-known fact that electrical properties of materials, namely dielectric constant and conductivity, are affected by the moisture content of material. This fact is important for the design of many commercial moisturetesting instruments for agricultural products. The knowledge of dielectric properties of materials is necessary for the application of dielectric heating. The aim of this work was to measure conductivity, dielectric constant and loss tangent on samples of sunflower achenes, the electrical properties of which had not been sufficiently measured. Measurements were performed under variable moisture content and the frequency of electric field ranging from 1 MHz to 16 MHz, using a Q meter with coaxial probe. It was concluded that conductivity, dielectric constant and loss tangent increased with increasing moisture content, and dielectric constant and loss tangent decreased as the frequency of electric field increased.

  13. Nuclear pseudogenes of mtDNA (NUMTS) suggest repeated distant inter-species hybridization among direct human ancestors

    OpenAIRE

    Gunbin, Konstantin; Popadin, Konstantin; Peshkin, Leonid; Annis, Sofia; Fleischmann, Zoe; Markuzon, Natasha; Kratysberg, Yevgenya; Ackermann, Rebecca; Khrapko, Konstantin

    2017-01-01

    Introduction: Increasingly, the emergence and evolution of our species is being tied to genetic exchange between divergent lineages within ~1Ma (e.g., Neanderthals, Denisovans). However, little is known about genetic exchange during earlier (pre-1Ma) human evolution and between more divergent lineages. Results: We present evidence of hybridization within human lineage, show that it likely happened between highly divergent (~4.5My) lineages, more than once. We use analysis of nuclear pseudogen...

  14. Land use and wind direction drive hybridization between cultivated poplar and native species in a Mediterranean floodplain environment.

    Science.gov (United States)

    Paffetti, Donatella; Travaglini, Davide; Labriola, Mariaceleste; Buonamici, Anna; Bottalico, Francesca; Materassi, Alessandro; Fasano, Gianni; Nocentini, Susanna; Vettori, Cristina

    2018-01-01

    Deforestation and intensive land use management with plantations of fast-growing tree species, like Populus spp., may endanger native trees not only by eliminating or reducing their habitats, but also by diminishing their species integrity via hybridization and introgression. The genus Populus has persistent natural hybrids because clonal and sexual reproduction is common. The objective of this study was to assess the effect of land use management of poplar plantations on the spatial genetic structure and species composition in poplar stands. Specifically, we studied the potential breeding between natural and cultivated poplar populations in the Mediterranean environment to gain insight into spontaneous hybridization events between exotic and native poplars; we also used a GIS-based model to evaluate the potential threats related to an intensive land use management. Two study areas, both near to poplar plantations (P.×euramericana), were designated in the native mixed stands of P. alba, P. nigra and P.×canescens within protected areas. We found that the spatial genetic structure differed between the two stands and their differences depended on their environmental features. We detected a hybridization event with P.×canescens that was made possible by the synchrony of flowering between the poplar plantation and P.×canescens and facilitated by the wind intensity and direction favoring the spread of pollen. Taken together, our results indicate that natural and artificial barriers are crucial to mitigate the threats, and so they should be explicitly considered in land use planning. For example, our results suggest the importance of conserving rows of trees and shrubs along rivers and in agricultural landscapes. In sum, it is necessary to understand, evaluate, and monitor the spread of exotic species and genetic material to ensure effective land use management and mitigation of their impact on native tree populations. Copyright © 2017 Elsevier B.V. All rights

  15. Evidence for past and present hybridization in three Antarctic icefish species provides new perspectives on an evolutionary radiation.

    Science.gov (United States)

    Marino, I A M; Benazzo, A; Agostini, C; Mezzavilla, M; Hoban, S M; Patarnello, T; Zane, L; Bertorelle, G

    2013-10-01

    Determining the timing, extent and underlying causes of interspecific gene exchange during or following speciation is central to understanding species' evolution. Antarctic notothenioid fish, thanks to the acquisition of antifreeze glycoproteins during Oligocene transition to polar conditions, experienced a spectacular radiation to >100 species during Late Miocene cooling events. The impact of recent glacial cycles on this group is poorly known, but alternating warming and cooling periods may have affected species' distributions, promoted ecological divergence into recurrently opening niches and/or possibly brought allopatric species into contact. Using microsatellite markers and statistical methods including Approximate Bayesian Computation, we investigated genetic differentiation, hybridization and the possible influence of the last glaciation/deglaciation events in three icefish species of the genus Chionodraco. Our results provide strong evidence of contemporary and past introgression by showing that: (i) a substantial fraction of contemporary individuals in each species has mixed ancestry, (ii) evolutionary scenarios excluding hybridization or including it only in ancient times have small or zero posterior probabilities, (iii) the data support a scenario of interspecific gene flow associated with the two most recent interglacial periods. Glacial cycles might therefore have had a profound impact on the genetic composition of Antarctic fauna, as newly available shelf areas during the warmer intervals might have favoured secondary contacts and hybridization between diversified groups. If our findings are confirmed in other notothenioids, they offer new perspectives for understanding evolutionary dynamics of Antarctic fish and suggest a need for new predictions on the effects of global warming in this group. © 2013 John Wiley & Sons Ltd.

  16. Interspecific amphiploid-derived alloplasmic male sterility with defective anthers, narrow disk florets, and small ray flowers in sunflower

    Science.gov (United States)

    The cytoplasmic male-sterility (CMS)/fertility-restoration system is important for hybrid sunflower (Helianthus annuus L.) seed production. Two novel alloplasmic CMSs, designated CMS GRO1 and CMS MAX3 with defective anthers, narrow disk florets with no swollen corolla, and short, narrow ray flowers,...

  17. Interspecific hybridization increases MHC class II diversity in two sister species of newts.

    Science.gov (United States)

    Nadachowska-Brzyska, Krystyna; Zieliński, Piotr; Radwan, Jacek; Babik, Wiesław

    2012-02-01

    Our understanding of the evolutionary mechanisms generating variation within the highly polymorphic major histocompatibility complex (MHC) genes remains incomplete. Assessing MHC variation across multiple populations, of recent and ancient divergence, may facilitate understanding of geographical and temporal aspects of variation. Here, we applied 454 sequencing to perform a large-scale, comprehensive analysis of MHC class II in the closely related, hybridizing newts, Lissotriton vulgaris (Lv) and Lissotriton montandoni (Lm). Our study revealed an extensive (299 alleles) geographically structured polymorphism. Populations at the southern margin of the Lv distribution, inhabited by old and distinct lineages (southern Lv), exhibited moderate MHC variation and strong population structure, indicating little gene flow or extensive local adaptation. Lissotriton vulgaris in central Europe and the northern Balkans (northern Lv) and almost all Lm populations had a high MHC variation. A much higher proportion of MHC alleles was shared between Lm and northern Lv than between Lm and southern Lv. Strikingly, the average pairwise F(ST) between northern Lv and Lm was significantly lower than between northern and southern Lv for MHC, but not for microsatellites. Thus, high MHC variation in Lm and northern Lv may result from gene flow between species. We hypothesize that the interspecific exchange of MHC genes may be facilitated by frequency-dependent selection. A marginally significant correlation between the MHC and microsatellite allelic richness indicates that demographic factors may have contributed to the present-day pattern of MHC variation, but unequivocal signatures of adaptive evolution in MHC class II sequences emphasize the role of selection on a longer timescale. © 2011 Blackwell Publishing Ltd.

  18. Hybrid approaches for multiple-species stochastic reaction–diffusion models

    Energy Technology Data Exchange (ETDEWEB)

    Spill, Fabian, E-mail: fspill@bu.edu [Department of Biomedical Engineering, Boston University, 44 Cummington Street, Boston, MA 02215 (United States); Department of Mechanical Engineering, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, MA 02139 (United States); Guerrero, Pilar [Department of Mathematics, University College London, Gower Street, London WC1E 6BT (United Kingdom); Alarcon, Tomas [Centre de Recerca Matematica, Campus de Bellaterra, Edifici C, 08193 Bellaterra (Barcelona) (Spain); Departament de Matemàtiques, Universitat Atonòma de Barcelona, 08193 Bellaterra (Barcelona) (Spain); Maini, Philip K. [Wolfson Centre for Mathematical Biology, Mathematical Institute, University of Oxford, Oxford OX2 6GG (United Kingdom); Byrne, Helen [Wolfson Centre for Mathematical Biology, Mathematical Institute, University of Oxford, Oxford OX2 6GG (United Kingdom); Computational Biology Group, Department of Computer Science, University of Oxford, Oxford OX1 3QD (United Kingdom)

    2015-10-15

    Reaction–diffusion models are used to describe systems in fields as diverse as physics, chemistry, ecology and biology. The fundamental quantities in such models are individual entities such as atoms and molecules, bacteria, cells or animals, which move and/or react in a stochastic manner. If the number of entities is large, accounting for each individual is inefficient, and often partial differential equation (PDE) models are used in which the stochastic behaviour of individuals is replaced by a description of the averaged, or mean behaviour of the system. In some situations the number of individuals is large in certain regions and small in others. In such cases, a stochastic model may be inefficient in one region, and a PDE model inaccurate in another. To overcome this problem, we develop a scheme which couples a stochastic reaction–diffusion system in one part of the domain with its mean field analogue, i.e. a discretised PDE model, in the other part of the domain. The interface in between the two domains occupies exactly one lattice site and is chosen such that the mean field description is still accurate there. In this way errors due to the flux between the domains are small. Our scheme can account for multiple dynamic interfaces separating multiple stochastic and deterministic domains, and the coupling between the domains conserves the total number of particles. The method preserves stochastic features such as extinction not observable in the mean field description, and is significantly faster to simulate on a computer than the pure stochastic model. - Highlights: • A novel hybrid stochastic/deterministic reaction–diffusion simulation method is given. • Can massively speed up stochastic simulations while preserving stochastic effects. • Can handle multiple reacting species. • Can handle moving boundaries.

  19. Estimating the Growth Rate of a Bacterial Species in a Complex Mixture by Hybridization of Genomic DNA

    Science.gov (United States)

    Pollard

    1998-09-01

    > Abstract Advances in molecular techniques have enabled new approaches to identifying bacteria. However, once identified, there is no quantitative information on the in situ growth rate of the species, mainly because the technology has not been available. The quantitative incorporation of [methyl-3H]thymidine into dividing bacteria is coupled with a molecular (hybridization) method, to determine the growth rate of bacterial species in situ. The basis of this molecular method is a reverse gene probe-natural populations are labeled in situ with [methyl-3H]thymidine. The probe (3H-Tdr-DNA) is captured, using a hybridization procedure, on a positively charged nylon membrane on which is attached non-labeled target DNA. Two bacterial species, Bacillus cereus and Zoogloea ramigera, were used to demonstrate the principle in laboratory cultures and in a municipal activate sludge treatment process. The DNA of the dividing bacteria in activated sludge was radioactively labeled with [methyl-3H]thymidine, and the DNA of Z. ramigera was recovered using a DNA hybridization method. The recovered radioactively-labeled DNA was used to estimate the growth rate (0.03 x 10(9) cells . ml-1 . h-1) of Z. ramigera in situ. Simultaneously applying these two powerful molecular-based methods could potentially be used to study bacterial population dynamics in situ.

  20. Widespread host-dependent hybrid unfitness in the pea aphid species complex.

    Science.gov (United States)

    Peccoud, Jean; de la Huerta, Manon; Bonhomme, Joël; Laurence, Cindy; Outreman, Yannick; Smadja, Carole M; Simon, Jean-Christophe

    2014-10-01

    Linking adaptive divergence to hybrid unfitness is necessary to understand the ecological factors contributing to reproductive isolation and speciation. To date, this link has been demonstrated in few model systems, most of which encompass ecotypes that occupy relatively early stages in the speciation process. Here we extend these studies by assessing how host-plant adaptation conditions hybrid fitness in the pea aphid, Acyrthosiphon pisum. We made crosses between and within five pea aphid biotypes adapted to different host plants and representing various stages of divergence within the complex. Performance of F1 hybrids and nonhybrids was assessed on a "universal" host that is favorable to all pea aphid biotypes in laboratory conditions. Although hybrids performed equally well as nonhybrids on the universal host, their performance was much lower than nonhybrids on the natural hosts of their parental populations. Hence, hybrids, rather than being intrinsically deficient, are maladapted to their parents' hosts. Interestingly, the impact of this maladaptation was stronger in certain hybrids from crosses involving the most divergent biotype, suggesting that host-dependent postzygotic isolation has continued to evolve late in divergence. Even though host-independent deficiencies are not excluded, hybrid maladaptation to parental hosts supports the hypothesis of ecological speciation in this complex. © 2014 The Author(s). Evolution © 2014 The Society for the Study of Evolution.

  1. Crude palm oil from interspecific hybrid Elaeis oleifera×Elaeis guineensis: fatty acid regiodistribution and molecular species of glycerides.

    Science.gov (United States)

    Mozzon, Massimo; Pacetti, Deborah; Lucci, Paolo; Balzano, Michele; Frega, Natale Giuseppe

    2013-11-01

    The composition and structure of triacylglycerols (TAGs) and partial glycerides of crude palm oil obtained from interspecific hybrid Elaeis oleifera×Elaeis guineensis, grown in Colombia, were fully characterised and compared to data obtained by analysing crude African palm oil. Hybridisation appears to substantially modify the biosynthesis of fatty acids (FAs) rather than their assembly in TAGs. In fact, total FAs analysis showed significant differences between these two types of oil, with hybrid palm oil having a higher percentage of oleic acid (54.6 ± 1.0 vs 41.4 ± 0.3), together with a lower saturated fatty acid content (33.5 ± 0.5 vs 47.3 ± 0.1), while the percentage of essential fatty acid, linoleic acid, does not undergo significant changes. Furthermore, 34 TAG types were identified, with no qualitative differences between African and E. guineensis×E. oleifera hybrid palm oil samples. Short and medium chain FAs (8:0, 10:0, 12:0, 14:0) were utilised, together, to build a restricted number of TAG molecular species. Oil samples from the E. guineensis×E. oleifera hybrid showed higher contents of monosaturated TAGs (47.5-51.0% vs 36.7-37.1%) and triunsaturated TAGs (15.5-15.6% vs 5.2-5.4%). The sn-2 position of TAGs in hybrid palm oil was shown to be predominantly esterified with oleic acid (64.7-66.0 mol% vs 55.1-58.2 mol% in African palm oil) with only 10-15% of total palmitic acid and 6-20% of stearic acid acylated in the secondary position. The total amount of diacylglycerols (DAGs) was in agreement with the values of free acidity; DAG types found were in agreement with the representativeness of different TAG species. Copyright © 2013 Elsevier Ltd. All rights reserved.

  2. Travelling in time with networks: Revealing present day hybridization versus ancestral polymorphism between two species of brown algae, Fucus vesiculosus and F. spiralis.

    Science.gov (United States)

    Moalic, Yann; Arnaud-Haond, Sophie; Perrin, Cécile; Pearson, Gareth A; Serrao, Ester A

    2011-01-31

    Hybridization or divergence between sympatric sister species provides a natural laboratory to study speciation processes. The shared polymorphism in sister species may either be ancestral or derive from hybridization, and the accuracy of analytic methods used thus far to derive convincing evidence for the occurrence of present day hybridization is largely debated. Here we propose the application of network analysis to test for the occurrence of present day hybridization between the two species of brown algae Fucus spiralis and F. vesiculosus. Individual-centered networks were analyzed on the basis of microsatellite genotypes from North Africa to the Pacific American coast, through the North Atlantic. Two genetic distances integrating different time steps were used, the Rozenfeld (RD; based on alleles divergence) and the Shared Allele (SAD; based on alleles identity) distances. A diagnostic level of genotype divergence and clustering of individuals from each species was obtained through RD while screening for exchanges through putative hybridization was facilitated using SAD. Intermediate individuals linking both clusters on the RD network were those sampled at the limits of the sympatric zone in Northwest Iberia. These results suggesting rare hybridization were confirmed by simulation of hybrids and F2 with directed backcrosses. Comparison with the Bayesian method STRUCTURE confirmed the usefulness of both approaches and emphasized the reliability of network analysis to unravel and study hybridization.

  3. Travelling in time with networks: Revealing present day hybridization versus ancestral polymorphism between two species of brown algae, Fucus vesiculosus and F. spiralis

    Directory of Open Access Journals (Sweden)

    Pearson Gareth A

    2011-01-01

    Full Text Available Abstract Background Hybridization or divergence between sympatric sister species provides a natural laboratory to study speciation processes. The shared polymorphism in sister species may either be ancestral or derive from hybridization, and the accuracy of analytic methods used thus far to derive convincing evidence for the occurrence of present day hybridization is largely debated. Results Here we propose the application of network analysis to test for the occurrence of present day hybridization between the two species of brown algae Fucus spiralis and F. vesiculosus. Individual-centered networks were analyzed on the basis of microsatellite genotypes from North Africa to the Pacific American coast, through the North Atlantic. Two genetic distances integrating different time steps were used, the Rozenfeld (RD; based on alleles divergence and the Shared Allele (SAD; based on alleles identity distances. A diagnostic level of genotype divergence and clustering of individuals from each species was obtained through RD while screening for exchanges through putative hybridization was facilitated using SAD. Intermediate individuals linking both clusters on the RD network were those sampled at the limits of the sympatric zone in Northwest Iberia. Conclusion These results suggesting rare hybridization were confirmed by simulation of hybrids and F2 with directed backcrosses. Comparison with the Bayesian method STRUCTURE confirmed the usefulness of both approaches and emphasized the reliability of network analysis to unravel and study hybridization

  4. Development of an ultra-dense genetic map of the sunflower genome based on single-feature polymorphisms.

    Directory of Open Access Journals (Sweden)

    John E Bowers

    Full Text Available The development of ultra-dense genetic maps has the potential to facilitate detailed comparative genomic analyses and whole genome sequence assemblies. Here we describe the use of a custom Affymetrix GeneChip containing nearly 2.4 million features (25 bp sequences targeting 86,023 unigenes from sunflower (Helianthus annuus L. and related species to test for single-feature polymorphisms (SFPs in a recombinant inbred line (RIL mapping population derived from a cross between confectionery and oilseed sunflower lines (RHA280×RHA801. We then employed an existing genetic map derived from this same population to rigorously filter out low quality data and place 67,486 features corresponding to 22,481 unigenes on the sunflower genetic map. The resulting map contains a substantial fraction of all sunflower genes and will thus facilitate a number of downstream applications, including genome assembly and the identification of candidate genes underlying QTL or traits of interest.

  5. Species boundaries and possible hybridization between the black mongoose (Galerella nigrata) and the slender mongoose (Galerella sanguinea).

    Science.gov (United States)

    Rapson, Sara A; Goldizen, Anne W; Seddon, Jennifer M

    2012-12-01

    Major climatic oscillations since the mid-Miocene climatic optimum are known to have played a key role in promoting speciation events. In this study we use molecular data to elucidate the evolutionary history of Galerella nigrata and link its divergence to known major climatic events. A total of 51 samples from G. nigrata and 17 from Galerella sanguinea were used to provide the first molecular evidence that G. nigrata may be a species in its own right. Both mitochondrial cytochrome b and the nuclear ß-fibrinogen intron seven sequences of G. nigrata form distinct monophyletic clades, separate from its sister species G. sanguinea. We estimate the divergence of these two species to have occurred 3.85-4.27 million years ago, coinciding with a period of the Plio-Pleistocene that was characterised by cooling global temperatures and strong aridity in southern Africa. However, evidence for potential hybridization between the two species was documented for ten individuals using phenotypic (pelage colouration) and/or molecular (nuclear and mtDNA sequences and microsatellite loci) data. There appeared to be a bias towards unidirectional hybridization with all potential hybrids showing mtDNA haplotypes from G. nigrata. We suggest that as the desert expanded across Namibia, G. sanguinea likely retreated with the savanna, leaving some mongooses stranded on the granite inselbergs of north-western Namibia. Subsequent adaptation of these mongooses to local conditions on granite inselbergs could have led to ecological speciation. Secondary contact zones would have been re-established with subsequent global warming events. It appears that the two species have not yet undergone complete reproductive isolation. Copyright © 2012 Elsevier Inc. All rights reserved.

  6. Interspecific hybridization among cultivars of hardy Hibiscus species section Muenchhusia

    DEFF Research Database (Denmark)

    Kuligowska, Katarzyna; Lütken, Henrik Vlk; Christensen, Brian

    2016-01-01

    Rose mallows belong to the Muenchhusia section of the Hibiscus genus. They represent a small group of cold tolerant North American plants and are popular ornamentals mainly because of their abundant, large and colorful flowers. Due to their geographical origin they are well suited for garden use...... growth revealed inhibition of pollen tubes and their abnormal growth. In specific crosses the fertilization success was low. The pre-fertilization barriers did not cause a complete reproductive isolation between the hybridization partners. In relation to post-fertilization barriers, the occurrence...... of hybrid incompatibilities such as unviability, chlorosis, necrosis, stunted growth and albinism were the main drawback in production of hybrids. The appearance of symptoms of hybrid incompatibilities was dependent upon specific parental plants. The obtained progeny had intermediate leaf morphology...

  7. New Hybrids between Saccharomyces Sensu Stricto Yeast Species Found among Wine and Cider Production Strains

    Science.gov (United States)

    Masneuf, Isabelle; Hansen, Jørgen; Groth, Casper; Piskur, Jure; Dubourdieu, Denis

    1998-01-01

    Two yeast isolates, a wine-making yeast first identified as a Mel+ strain (ex. S. uvarum) and a cider-making yeast, were characterized for their nuclear and mitochondrial genomes. Electrophoretic karyotyping analyses, restriction fragment length polymorphism maps of PCR-amplified MET2 gene fragments, and the sequence analysis of a part of the two MET2 gene alleles found support the notion that these two strains constitute hybrids between Saccharomyces cerevisiae and Saccharomyces bayanus. The two hybrid strains had completely different restriction patterns of mitochondrial DNA as well as different sequences of the OLI1 gene. The sequence of the OLI1 gene from the wine hybrid strain appeared to be the same as that of the S. cerevisiae gene, whereas the OLI1 gene of the cider hybrid strain is equally divergent from both putative parents, S. bayanus and S. cerevisiae. Some fermentative properties were also examined, and one phenotype was found to reflect the hybrid nature of these two strains. The origin and nature of such hybridization events are discussed. PMID:9758815

  8. Comparison of proximate composition and sensory attributes ofClariidcatfish species ofClarias gariepinus,Heterobranchus bidorsalis, and their hybrids.

    Science.gov (United States)

    Olaniyi, Wasiu A; Makinde, Olukayode A; Omitogun, Ofelia G

    2017-03-01

    Clariid catfish are favorite food fish especially in African and Asian continents. Recently there has been preference for particular species or hybrids of these species based on quality assurance and value addition. Consequently, this study aimed to evaluate the possible effect of different catfish species and their hybrids on proximate composition and sensory attributes. Catfish species, Clarias gariepinus (CC), Heterobranchus bidorsalis (HH), with their hybrid (CH), and reciprocal hybrid (HC) were evaluated for sensory variables - cognitive (sweet, salty, sour, bitter, and recent characteristic taste 'umami' ) and qualitative (texture, aroma, flavor, and color) tests; and nutritional variables - proximate composition (moisture, protein, ether/fat, and ash). A 5-point hedonic scale from 'neutral/neither like nor dislike' to 'excellent/like extremely' was employed in sensory testing. The results showed similar ( P  > 0.05) high moisture contents (>70%) in all species and high but different ( P   0.05) across species (>57%). Fat or ether extract was different ( P  attributes. All the fish species did not rate 'excellent/like extremely' for any attribute. It can be concluded that the parent catfish species possess better sensory qualities than hybrids, but all species need exogenous enhancement to their natural sensory components.

  9. Molecular analysis of a new cytoplasmic male sterile genotype in sunflower

    NARCIS (Netherlands)

    Spassova, Mariana; Christov, Michail; Bohorova, Natasha; Petrov, Peter; Dudov, Kalin; Atanassov, Atanas; Nijkamp, H. John J.; Hille, Jaques

    1992-01-01

    Mitochondrial DNA from 1 fertile and 6 cytoplasmic male sterile (CMS) sunflower genotypes was studied. The CMS genotypes had been obtained either by specific crosses between different Helianthus species or by mutagenesis. CMS-associated restriction fragment length polymorphisms (RFLPs) were found in

  10. Collection of wild Helianthus anomalus and deserticola sunflower from the desert southwest USA

    Science.gov (United States)

    Genetic resources are the biological basis of global food security. Collection and preservation of wild relatives of important crop species such as sunflower provide the basic foundation to improve and sustain the crop. Acquisition through exploration is the initial step in the germplasm conservatio...

  11. Asymmetry of frontal bristles and postocular setae in species and hybrids of the Anastrepha fraterculus complex (Diptera, Tephritidae

    Directory of Open Access Journals (Sweden)

    João Maria G.A. Souza

    2007-01-01

    Full Text Available Asymmetry of the frontal bristles and postocular setae was studied in samples from natural populations and laboratory colonies of Anastrepha sp. 1 aff. fraterculus, of A. sp. 2 aff. fraterculus, and in F1 hybrids obtained from laboratory reciprocal crosses. Natural populations were sampled in a zone of sympatry and in two geographically distant regions with different climatic conditions. Asymmetry was scored as the differences between the number of bristles and of setae on the right and left sides of the head, males and females analyzed independently. The two traits exhibited variability according to the model of fluctuating asymmetry (FA. No significant differences among samples were found in the FA of frontal bristles. A significant FA was observed for the postocular setae of A. sp. 1 males from a southern population (Vacaria, RS as compared to the asymmetry exhibited by males and females of some other samples. No significant differences in FA were observed among the interspecific hybrids and the laboratory samples of both parental species. The higher FA found in the males from Vacaria was attributed to climatic conditions prevailing in that region. The absence of a higher FA in hybrids may be related to the relatively recent evolutionary history of the two species.

  12. Origin of year-long bean (Phaseolus dumosus Macfady, Fabaceae) from reticulated hybridization events between multiple Phaseolus species.

    Science.gov (United States)

    Mina-Vargas, Angela M; McKeown, Peter C; Flanagan, Nicola S; Debouck, Daniel G; Kilian, Andrzej; Hodkinson, Trevor R; Spillane, Charles

    2016-08-06

    Improved understanding of the secondary gene pools of crops is essential for advancing genetic gain in breeding programmes. Common bean, Phaseolus vulgaris, is a staple crop with several wild relatives in its secondary gene pool. The year-long bean, P. dumosus, an important crop in Guatemala, is considered particularly closely related to P. vulgaris and a potential source of novel variation. However, the genetic diversity and relationship to other Phaseolus species of P. dumosus remain unclear. We conducted the first comprehensive investigation of P. dumosus genetic diversity using both nuclear and chloroplast genome markers. Our nuclear marker set included over 700 markers present within the Phaseolus DArT (Diversity Arrays Technology) array, which we applied to P. dumosus and other relatives of P. vulgaris (including every secondary gene pool species: P. acutifolius, P. albescens, P. coccineus and P. costaricensis). Phaseolus dumosus arose from hybridization of P. vulgaris and P. coccineus, followed by at least two later hybridizations with sympatric congener populations. Existing P. dumosus collections have low genetic diversity. The under-utilized crop P. dumosus has a complex hybrid origin. Further sampling in the region in which it arose may uncover additional germplasm for introgressing favourable traits into crops within the P. vulgaris gene pool. © The Author 2016. Published by Oxford University Press on behalf of the Annals of Botany Company. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  13. Sunflower

    Directory of Open Access Journals (Sweden)

    Ricardo Daniel Gomes Ferreira

    2016-02-01

    Full Text Available Some people are born with the wish of being different: some want to be politicians to mark the History in their country, others want to be football players, others want to have an “ability” that makes them special, like flying, reading people’s minds, mind control, etc, but aren’t we perfect as we are? Normality is the only perfection in our lives, but the thirst for power prevents us from doing the right thing. Even if we have a good heart, we are always prone to corruption, so as to fulfill our thirst for power.  We have the example of some politicians and other people in charge of enterprises who had power but used it for their own good, even if that meant harming people others. The short story that I present is completely original, but it’s a criticism of the corruptive influence of power. We can say that “If you want to know a man, give him power”.

  14. Registration of an oilseed sunflower germplasm HA-DM1 resistant to sunflower downy mildew

    Science.gov (United States)

    HA-DM1 (Reg. No.xxx, PI 674793) sunflower (Helianthus annuus L.) germplasm was developed and released cooperatively by the USDA-ARS, Sunflower and Plant Biology Research Unit and the North Dakota Agricultural Experiment Station in 2015. HA-DM1 is a BC2F4 derived oilseed maintainer line from the cros...

  15. Evaluating the accuracy of genomic prediction of growth and wood traits in two Eucalyptus species and their F1 hybrids.

    Science.gov (United States)

    Tan, Biyue; Grattapaglia, Dario; Martins, Gustavo Salgado; Ferreira, Karina Zamprogno; Sundberg, Björn; Ingvarsson, Pär K

    2017-06-29

    Genomic prediction is a genomics assisted breeding methodology that can increase genetic gains by accelerating the breeding cycle and potentially improving the accuracy of breeding values. In this study, we use 41,304 informative SNPs genotyped in a Eucalyptus breeding population involving 90 E.grandis and 78 E.urophylla parents and their 949 F1 hybrids to develop genomic prediction models for eight phenotypic traits - basic density and pulp yield, circumference at breast height and height and tree volume scored at age three and six years. We assessed the impact of different genomic prediction methods, the composition and size of the training and validation set and the number and genomic location of SNPs on the predictive ability (PA). Heritabilities estimated using the realized genomic relationship matrix (GRM) were considerably higher than estimates based on the expected pedigree, mainly due to inconsistencies in the expected pedigree that were readily corrected by the GRM. Moreover, the GRM more precisely capture Mendelian sampling among related individuals, such that the genetic covariance was based on the true proportion of the genome shared between individuals. PA improved considerably when increasing the size of the training set and by enhancing relatedness to the validation set. Prediction models trained on pure species parents could not predict well in F1 hybrids, indicating that model training has to be carried out in hybrid populations if one is to predict in hybrid selection candidates. The different genomic prediction methods provided similar results for all traits, therefore either GBLUP or rrBLUP represents better compromises between computational time and prediction efficiency. Only slight improvement was observed in PA when more than 5000 SNPs were used for all traits. Using SNPs in intergenic regions provided slightly better PA than using SNPs sampled exclusively in genic regions. The size and composition of the training set and number of SNPs

  16. Fusarium foetens, a new species pathogenic to begonia elatior hybrids (Begonia x hiemalis) and the sister taxon of the Fusarium oxysporum species complex.

    Science.gov (United States)

    Schroers, H-J; Baayen, R P; Meffert, J P; de Gruyter, J; Hooftman, M; O'Donnell, K

    2004-01-01

    A new disease recently was discovered in begonia elatior hybrid (Begonia × hiemalis) nurseries in The Netherlands. Diseased plants showed a combination of basal rot, vein yellowing and wilting and the base of collapsing plants was covered by unusually large masses of Fusarium macroconidia. A species of Fusarium was isolated consistently from the discolored veins of leaves and stems. It differed morphologically from F. begoniae, a known agent of begonia flower, leaf and stem blight. The Fusarium species resembled members of the F. oxysporum species complex in producing short monophialides on the aerial mycelium and abundant chlamydospores. Other phenotypic characters such as polyphialides formed occasionally in at least some strains, relatively long monophialides intermingled with the short monophialides formed on the aerial mycelium, distinct sporodochial conidiomata, and distinct pungent colony odor distinguished it from the F. oxysporum species complex. Phylogenetic analyses of partial sequences of the mitochondrial small subunit of the ribosomal DNA (mtSSU rDNA), nuclear translation elongation factor 1α (EF-1α) and β-tubulin gene exons and introns indicate that the Fusarium species represents a sister group of the F. oxysporum species complex. Begonia × hiemalis cultivars Bazan, Bellona and Netja Dark proved to be highly susceptible to the new species. Inoculated plants developed tracheomycosis within 4 wk, and most died within 8 wk. The new taxon was not pathogenic to Euphorbia pulcherrima, Impatiens walleriana and Saintpaulia ionantha that commonly are grown in nurseries along with B. × hiemalis. Inoculated plants of Cyclamen persicum did not develop the disease but had discolored vessels from which the inoculated fungus was isolated. Given that the newly discovered begonia pathogen is distinct in pathogenicity, morphology and phylogeny from other fusaria, it is described here as a new species, Fusarium foetens.

  17. New hybrids between Saccharomyces sensu stricto yeast species found among wine and cider production strains

    DEFF Research Database (Denmark)

    Masneuf, I; Hansen, J.; Groth, C

    1998-01-01

    Two yeast isolates, a wine-making yeast first identified as a Mel(+) strain (ex. S. uvarum) and a cider-making yeast, were characterized for their nuclear and mitochondrial genomes, Electrophoretic karyotyping analyses, restriction fragment length polymorphism maps of PCR-amplified MET2 gene...... as different sequences of the OLI1 gene. The sequence of the OLI1 gene from the wine hybrid strain appeared to be the same as that of the S. cerevisiae gene, whereas the OLI1 gene of the cider hybrid strain its equally divergent from both putative parents, S. bayanus and S, cerevisiae, Some fermentative...

  18. SNP Discovery and Development of a High-Density Genotyping Array for Sunflower

    Science.gov (United States)

    Bachlava, Eleni; Taylor, Christopher A.; Tang, Shunxue; Bowers, John E.; Mandel, Jennifer R.; Burke, John M.; Knapp, Steven J.

    2012-01-01

    Recent advances in next-generation DNA sequencing technologies have made possible the development of high-throughput SNP genotyping platforms that allow for the simultaneous interrogation of thousands of single-nucleotide polymorphisms (SNPs). Such resources have the potential to facilitate the rapid development of high-density genetic maps, and to enable genome-wide association studies as well as molecular breeding approaches in a variety of taxa. Herein, we describe the development of a SNP genotyping resource for use in sunflower (Helianthus annuus L.). This work involved the development of a reference transcriptome assembly for sunflower, the discovery of thousands of high quality SNPs based on the generation and analysis of ca. 6 Gb of transcriptome re-sequencing data derived from multiple genotypes, the selection of 10,640 SNPs for inclusion in the genotyping array, and the use of the resulting array to screen a diverse panel of sunflower accessions as well as related wild species. The results of this work revealed a high frequency of polymorphic SNPs and relatively high level of cross-species transferability. Indeed, greater than 95% of successful SNP assays revealed polymorphism, and more than 90% of these assays could be successfully transferred to related wild species. Analysis of the polymorphism data revealed patterns of genetic differentiation that were largely congruent with the evolutionary history of sunflower, though the large number of markers allowed for finer resolution than has previously been possible. PMID:22238659

  19. Evaluation of Cover Crops with Potential for Use in Anaerobic Soil Disinfestation (ASD) for Susceptibility to Three Species of Meloidogyne.

    Science.gov (United States)

    Kokalis-Burelle, Nancy; Butler, David M; Rosskopf, Erin N

    2013-12-01

    Several cover crops with potential for use in tropical and subtropical regions were assessed for susceptibility to three common species of root-knot nematode, Meloidogyne arenaria, M. incognita, and M. javanica. Crops were selected based on potential use as organic amendments in anaerobic soil disinfestation (ASD) applications. Nematode juvenile (J2) numbers in soil and roots, egg production, and host plant root galling were evaluated on arugula (Eruca sativa, cv. Nemat), cowpea (Vigna unguiculata, cv. Iron & Clay), jack bean (Canavalia ensiformis, cv. Comum), two commercial mixtures of Indian mustard and white mustard (Brassica juncea & Sinapis alba, mixtures Caliente 61 and Caliente 99), pearl millet (Pennisetum glaucum, cv. Tifleaf III), sorghum-sudangrass hybrid (Sorghum bicolor × S. bicolor var. sudanense, cv. Sugar Grazer II), and three cultivars of sunflower (Helianthus annuus, cvs. 545A, Nusun 660CL, and Nusun 5672). Tomato (Solanum lycopersicum, cv. Rutgers) was included in all trials as a susceptible host to all three nematode species. The majority of cover crops tested were less susceptible than tomato to M. arenaria, with the exception of jack bean. Sunflower cv. Nusun 5672 had fewer M. arenaria J2 isolated from roots than the other sunflower cultivars, less galling than tomato, and fewer eggs than tomato and sunflower cv. 545A. Several cover crops did not support high populations of M. incognita in roots or exhibit significant galling, although high numbers of M. incognita J2 were isolated from the soil. Arugula, cowpea, and mustard mixture Caliente 99 did not support M. incognita in soil or roots. Jack bean and all three cultivars of sunflower were highly susceptible to M. javanica, and all sunflower cultivars had high numbers of eggs isolated from roots. Sunflower, jack bean, and both mustard mixtures exhibited significant galling in response to M. javanica. Arugula, cowpea, and sorghum-sudangrass consistently had low numbers of all three

  20. Evaluation of the courtship and of the hybrid male sterility among Drosophila buzzatii cluster species (Diptera, Drosophilidae

    Directory of Open Access Journals (Sweden)

    MACHADO L. P. de B.

    2002-01-01

    Full Text Available In the Drosophila repleta group the establishment of subgroups and complexes made on the basis of morphological and cytological evidences is supported by tests of reproductive isolation. Among species in the repleta group, the buzzatii cluster, due to its polymorphism and polytipism, is an excellent material for ecological and speciation studies. Some interspecific crosses involving Drosophila seriema, Drosophila sp. B, D. koepferae and D. buzzatii strains were completely sterile while others involving strains from these species produced F1 hybrids that did not yield F2. In the present work, data on courtship duration and copula occurrence obtained in the analysis of flies from parental sterile crosses and on spermatozoon mobility observed in F1 hybrids that did not yield F2 are presented. Copula did not occur during one hour of observation and the spermatozoon also did not show mobility at any of the analyzed stages (3, 7, 9 and 10 days old. There was a high variation in courtship average duration and in the percentage of males that courted the females. The reproductive isolation mechanisms indicated by these observations were pre and post-zygotic, as supported by the absence of copula and male sterility. Data obtained also showed the occurrence of different degrees of reproductive compatibility among the strains classified as the same species but from distinct geographic localities.

  1. Filtration of sunflower oil in the field of vibroacoustic effects

    National Research Council Canada - National Science Library

    S. A. Bredikhin; F. Y. Rudik; M. S. Tuliyeva

    2017-01-01

    Purification of crude unrefined sunflower oil along with the removal of primary oxidation products is an urgent task to remove the solid constituents formed during the processing of sunflower seeds...

  2. Risk analysis of exotic fish species included in the Dutch Fisheries Act and their hybrids

    NARCIS (Netherlands)

    Schiphouwer, M.E.; Kessel, van N.; Matthews, J.; Leuven, R.S.E.W.; Koppel, S.; Kranenbarg, J.; Haenen, O.L.M.; Lenders, H.J.R.; Nagelkerke, L.A.J.; Velde, van der G.; Crombaghs, B.; Zollinger, R.

    2014-01-01

    In dit rapport worden de risico’s geanalyseerd van exotische vissoorten die zijn opgenomen in de Visserijwet en hun hybriden. De volgende soorten en één specifieke hybride zijn in de analyse meegenomen: beekridder (Salvelinus alpinus); roofblei (Leuciscus aspius); karper (Cyprinus carpio);

  3. Species integrity enhanced by a predation cost to hybrids in the wild

    DEFF Research Database (Denmark)

    Nilsson, P. A.; Hulthén, Kaj; Chapman, Ben B.

    2017-01-01

    ) and their hybrids in 2005. Tagged fish were returned to their lake of origin, exposing them to natural predation risk from apex avian predators (great cormorant, Phalacrocorax carbo). Scanning for regurgitated tags under cormorant roosts 3-4 years later identified cormorant-killed individual fish and allowed us...

  4. The influence of hybridization on epidermal properties of birch species and the consequences for palaeoclimatic interpretations

    NARCIS (Netherlands)

    Wagner, F.; Kürschner, W.M.; Neuvonen, S.; Visscher, H.

    2000-01-01

    The Fennoscandian birch population primarily consists of Betula nana, B. pendula and B. pubescens ssp. czerepanovii, the Mountain birch. Frequent hybridization between the Mountain birch and B. nana generates a wide range of genotypic and phenotypic plasticity in the subarctic birch zone of

  5. Complex patterns of hybridization between exotic and native North American poplar species

    NARCIS (Netherlands)

    Meirmans, P.G.; Lamothe, M.; Gros-Louis, M.C.; Khasa, D.; Périnet, P.; Bousquet, J.; Isabel, N.

    2010-01-01

    • Premise of the study: Poplars and their hybrids are seen as important candidates for bioenergy initiatives. However, many concerns have been raised about large-scale plantations of new poplar cultivars. The deployment of such plants with novel traits brings the risk of potential spread of novel

  6. A sunflower WRKY transcription factor stimulates the mobilization of seed-stored reserves during germination and post-germination growth.

    Science.gov (United States)

    Raineri, Jesica; Hartman, Matías D; Chan, Raquel L; Iglesias, Alberto A; Ribichich, Karina F

    2016-09-01

    The sunflower transcription factor HaWRKY10 stimulates reserves mobilization in Arabidopsis. Gene expression and enzymes activity assays indicated that lipolysis and gluconeogenesis were increased. Microarray results suggested a parallelism in sunflower. Germinating oilseeds converts stored lipids into sugars, and thereafter in metabolic energy that is used in seedling growth and establishment. During germination, the induced lipolysis linked to the glyoxylate pathway and gluconeogenesis produces sucrose, which is then transported to the embryo and driven through catabolic routes. Herein, we report that the sunflower transcription factor HaWRKY10 regulates carbon partitioning by reducing carbohydrate catabolism and increasing lipolysis and gluconeogenesis. HaWRKY10 was regulated by abscisic acid and gibberellins in the embryo leaves 48 h after seed imbibition and highly expressed during sunflower seed germination and seedling growth, concomitantly with lipid mobilization. Sunflower leaf disks overexpressing HaWRKY10 showed repressed expression of genes related to sucrose cleavage and glycolysis compared with controls. Moreover, HaWRKY10 constitutive expression in Arabidopsis seeds produced higher decrease in lipid reserves, whereas starch and sucrose were more preserved compared with wild type. Gene transcripts abundance and enzyme activities involved in stored lipid mobilization and gluconeogenesis increased more in transgenic than in wild type seeds 36 h after imbibition, whereas the negative regulator of lipid mobilization, ABI4, was repressed. Altogether, the results point out a functional parallelism between tissues and plant species, and reveal HaWRKY10 as a positive regulator of storage reserve mobilization in sunflower.

  7. A potential species-specific molecular marker suggests interspecific hybridization between sibling species Littorina arcana and L. saxatilis (Mollusca, Caenogastropoda) in natural populations.

    Science.gov (United States)

    Mikhailova, Natalia A; Gracheva, Yulia A; Backeljau, Thierry; Granovitch, Andrey I

    2009-12-01

    Three sister species of rough periwinkles, viz. Littorina saxatilis (Olivi 1792), L. arcana (Hannaford Ellis 1978) and L. compressa (Jeffreys 1865) from the Barents Sea (Russia), the White Sea (Russia) and the Norwegian Sea (Norway) were studied. The identification of two sibling species L. saxatilis and L. arcana is often difficult as both species have extremely similar shell morphology and reproductive systems. Only mature females can be unambiguously distinguished, with a jelly gland present in female L. arcana, but which is replaced by a brood pouch containing developing embryos in L. saxatilis. No clear-cut diagnostic features have been found to discriminate between males or juveniles of the two species. The very first diagnostic DNA marker (DNA fragment A2.8, 271 bp length) for L. arcana and L. saxatilis separation was developed. The marker was derived from apparently species-specific L. arcana DNA fragments obtained via Random Amplified Polymorphic DNA (RAPD) analysis. This fragment was cloned and sequenced, whereupon specific primers were designed and the amplification was surveyed in a large number of morphologically well-identified females of both species. Subsequently, the specific DNA marker was used for the identification of male L. arcana and partners in copulating pairs. In this way, we obtained evidence of possible interspecific hybridization between the sibling species L. arcana and L. saxatilis living in sympatry in natural populations: the presence of A2.8 fragment in 12% of morphologically well identified L. saxatilis females and its absence in 14% of morphologically well identified L. arcana females. The A2.8 fragment never amplified in L. saxatilis from sites without L. arcana. The A2.8 fragment did not amplify in L. compressa, not even in microsympatric populations, and we did not observe interspecific copulations between L. arcana and L. compressa.

  8. Identification and Characterization of VNI/VNII and Novel VNII/VNIV Hybrids and Impact of Hybridization on Virulence and Antifungal Susceptibility Within the C. neoformans/C. gattii Species Complex

    Science.gov (United States)

    Aminnejad, Mojgan; Cogliati, Massimo; Duan, Shuyao; Arabatzis, Michael; Tintelnot, Kathrin; Castañeda, Elizabeth; Lazéra, Marcia; Velegraki, Aristea; Ellis, David; Sorrell, Tania C.; Meyer, Wieland

    2016-01-01

    Cryptococcus neoformans and C. gattii are pathogenic basidiomycetous yeasts and the commonest cause of fungal infection of the central nervous system. Cryptococci are typically haploid but several inter-species, inter-varietal and intra-varietal hybrids have been reported. It has a bipolar mating system with sexual reproduction occurring normally between two individuals with opposite mating types, α and a. This study set out to characterize hybrid isolates within the C. neoformans/C. gattii species complex: seven unisexual mating intra-varietal VNI/VNII (αAAα) and six novel inter-varietal VNII/VNIV (aADα). The URA5-RFLP pattern for VNII/VNIV (aADα) differs from the VNIII (αADa) hybrids. Analysis of the allelic patterns of selected genes for AD hybrids showed 79% or more heterozygosis for the studied loci except for CBS132 (VNIII), which showed 50% of heterozygosity. MALDI-TOF MS was applied to hybrids belonging to different sero/mating type allelic patterns. All hybrid isolates were identified as belonging to the same hybrid group with identification scores ranging between 2.101 to 2.634. All hybrids were virulent when tested in the Galleria mellonella (wax moth) model, except for VNII/VNIV (aADα) hybrids. VNI/VGII hybrids were the most virulent hybrids. Hybrids recovered from larvae manifested a significant increase in capsule and total cell size and produced a low proportion (5–10%) of giant cells compared with the haploid control strains. All strains expressed the major virulence factors—capsule, melanin and phospholipase B—and grew well at 37°C. The minimal inhibitory concentration of nine drugs was measured by micro-broth dilution and compared with published data on haploid strains. MICs were similar amongst hybrids and haploid parental strains. This is the first study reporting natural same sex αAAα intra-varietal VNI/VNII hybrids and aADα inter-varietal VNII/VNIV hybrids. PMID:27764108

  9. Natural infection of several Coffea species and hybrids and Psilanthus ebracteolatus by the coffee ringspot virus (CoRSV

    Directory of Open Access Journals (Sweden)

    Elliot Watanabe Kitajima

    2011-08-01

    Full Text Available Coffee ringspot is a minor coffee disease caused by the nuclear type of Brevipalpus mite-transmitted virus, Coffee ringspot virus (CoRSV. Recently outbreaks of the disease in some growing regions of the state of Minas Gerais, Brazil, were registered with qualitative and quantitative yield losses. Coffea arabica was the only species registered as natural host. A survey was made on a germplasm collection of Coffea and related species kept at the Centro de Café "Alcides Carvalho", Instituto Agronômico, Campinas, state of São Paulo (SP, Brazil, to assess natural susceptibility of Coffee species, other than C. arabica and some interspecific hybrids of Coffea as well as other non-Coffea plant species to the Coffee ringspot virus (CoRSV. The following plants were found with ringspot symptoms on their leaves and/or fruits besides C. arabica L.: C. kapakata (IAC 4511, C. dewevrei cv. Excelsa, C. canephora cv. Robusta, hybrid derivative of the C. arabica × C. racemosa (IAC1195-5-6-2, C. arabica × C. dewerei (Piatã IAC 387, Híbrido de Timor CIFC 832/1 (derivative from a natural crossing between C. arabica × C. canephora and C. racemosa. Also Psilanthus ebracteolatus, a species close to the genus Coffee was also found with ringspot lesions on their leaves. All these plants were also found infested by Brevipalpus mites identified as B. phoenicis. Infection of these plants by CoRSV was confirmed by the observation of characteristic cytopathic effects in the tissues of the lesion and by RT-PCR using a pair of primer specific for CoRSV. Only with C. racemosa RT-PCR failed to amplify the CoRSV genome. The susceptibility of P. ebracteolatus to CoRSV adds new dimension regarding its controversial taxonomic position.

  10. A Partial Equilibrium Analysis of Sunflower Market in Turkey

    OpenAIRE

    B. Miran; G. Unakitan

    2006-01-01

    Sunflower oil is the most preferred vegetable oil in Turkey. 35% of total consumption of vegetable oil issunflower oil. Sunflower seed import is approximately 500-650 thousand tons while sunflower seedproduction is 800-850 thousand tons in the last years. The main objective of this study is to determine thereasons of deficiency of vegetable oil in Turkey and to suggest some solutions. For this objective, theprospective situation and the market structure of sunflower seed in Turkey has estimat...

  11. Características fenológicas, produtivas e qualitativas de híbridos de girassol em diferentes épocas de semeadura para produção de silagem Sowing dates effects on the phenology, yield and qualitative traits of sunflower hybrids for silage making

    Directory of Open Access Journals (Sweden)

    Renius Mello

    2006-06-01

    ógica.The objective of this study was to estimate the effect of three sowing dates: October (early, November (normal and December (late, on the phenological, yield and qualitative traits of four sunflower hybrids: Rumbosol-91 (forage, M-734 (double purpose, C-11 (double purpose and BRS-191 (grain grown for silage making. A 4 x 3 factorial treatment combination (four hybrids x three sowing dates was allocated in a randomized block design with four replications. The October sowing brought about longer cycle, higher plant height, and smaller seed head diameter and contribution due to the prevailing climatic conditions of lower temperature, insolation and photoperiod during the crop growth period. The Rumbosol-91 and BRS-191 hybrids sowed in November showed higher lodging plus stalk breaking proportion of about 49.6 and 65.7%, respectively. The BRS-191 and M-734 hybrids sowed in December showed higher biomass yields of 39.71 and 43.76 t ha-1 fresh matter and 11.31 and 11.41 t ha-1 drymatter, respectively. While the CP content increased, the NDF, ADF and ADL contents decreased from the stem, to the leaf and to the head plant fractions. The whole plant DM values ranged from 23.2% in the Rumbosol-91 hybrid sowed in November to 47.9% in the C-11 hybrid sowed in December, indicating that the hybrids have differentiated moisture retention capacity at similar physiologic maturity of the culture (R-9 phase. The CP values ranged from 7.0 to 15.7%, an evidence of the high protein content of the culture. The ADL values of the whole plant ranged among 6.5 to 12.4%, with lowest values for the M-734 hybrid sowed in December and C-11 hybrid sowed in October. The M-734 hybrid sowed in December has better relationship among phenology, yield and bromatological composition, traits required for the making of high quality silage.

  12. 7 CFR 810.1801 - Definition of sunflower seed.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 7 2010-01-01 2010-01-01 false Definition of sunflower seed. 810.1801 Section 810... STATES STANDARDS FOR GRAIN United States Standards for Sunflower Seed Terms Defined § 810.1801 Definition of sunflower seed. Grain that, before the removal of foreign material, consists of 50.0 percent or...

  13. Frankfurter Type Sausage Production with Sunflower Oil Substitution

    OpenAIRE

    Ertaş, A. Hamdi; KARABAŞ, Gülay

    1998-01-01

    Some quality characteristics of frankfurter type sausages (with 30% total fat) produced by adding sunflower oil at different levels (10%, 20% and 30%) were determined and compared to control with 30% animal fat. Increasing of sunflower oil content resulted in lower process yield. Cholesterol content and water holding capacity of frankfurters also decreased at the levels of sunflower oil from 10 to 30% (P

  14. Sunflower disease and insect pests in Pakistan: A review | Mukhtar ...

    African Journals Online (AJOL)

    ... insects and nematodes attack damage the sunflower crop, results a wide range of loss in production and yield. Sunflower is susceptible to diseases of various kinds. The most serious diseases of sunflower are caused by fungi. The major diseases include rust, downy mildew, Verticillium wilt, Sclerotinia stalk and head rot, ...

  15. Progress on introduction of rust resistance genes into confection sunflower

    Science.gov (United States)

    Sunflower rust (Puccinia helianthi) emerged as a serious disease in the last few years. Confection sunflower is particularly vulnerable to the disease due to the lack of resistance sources. The objectives of this project are to transfer rust resistance genes from oil sunflower to confectionery sunfl...

  16. Loss of sunflower seeds to columbids in South Africa: economic ...

    African Journals Online (AJOL)

    A survey across the sunflower production region of South Africa during November 2003 to July 2005 estimated the loss of sunflower seeds to columbids (doves and pigeons, Aves: Columbidae). Farmers estimated that 12.7% of the national yield was lost to columbids. In a follow-up survey, 37 sunflower fields were visited ...

  17. Nucleic acid spot hybridization based species-specific detection of Sclerotium rolfsii associated with collar rot disease of Amorphophallus paeoniifolius.

    Science.gov (United States)

    Pravi, V; Jeeva, M L; Archana, P V

    2015-02-01

    Collar rot is one of the most destructive and prevalent disease of Amorphophallus paeoniifolius, resulting in heavy yield losses. The causative organism, Sclerotium rolfsii is a soil-borne polyphagous fungus characterized by prolific growth and ability to produce persistent sclerotia. The pathogen propagules surviving in soil and planting material are the major sources of inoculum. This study presents the suitability of DNA hybridization technique for species specific detection of S. rolfsii in soil and planting material. The detection limit of the probe was 10-15 pg of pure pathogen DNA. The developed probe was found to be highly specific and could be used for accurate identification of pathogen up to the species level. The protocol was standardized for detection of the pathogen in naturally infected field samples.

  18. Relative resistance or susceptibility of maple (Acer) species, hybrids and cultivars to six arthropod pests of production nurseries.

    Science.gov (United States)

    Seagraves, Bonny L; Redmond, Carl T; Potter, Daniel A

    2013-01-01

    Maples (Acer spp.) in production nurseries are vulnerable to numerous arthropod pests that can stunt or even kill the young trees. Seventeen cultivars representing various Acer species and hybrids were evaluated for extent of infestation or injury by shoot and trunk borers (Proteoteras aesculana, Chrysobothris femorata), potato leafhopper (Empoasca fabae), Japanese beetle (Popillia japonica), maple spider mite (Oligonychus aceris) and calico scale (Eulecanium cerasorum). Evaluations were done in replicated field plots in central and western Kentucky. All of the maples were susceptible, to varying degrees, to one or more key pest(s). Red maples (A. rubrum) were relatively vulnerable to potato leafhopper injury and borers but nearly free of Japanese beetle feeding and spider mites. Sugar maples sustained conspicuous Japanese beetle damage but had very low mite populations, whereas the opposite was true for Freeman maples (A. × freemanii). A. campestre was heavily infested by calico scale. Within each species or hybrid there were cultivar differences in degree of infestation or damage by particular pests. The results should help growers to focus pest management efforts on those plantings at greatest risk from particular pests, and to choose cultivars requiring fewer insecticide inputs to produce a quality tree. Copyright © 2012 Society of Chemical Industry.

  19. Sunflower genetic, genomic and ecological resources.

    Science.gov (United States)

    Kane, Nolan C; Burke, John M; Marek, Laura; Seiler, Gerald; Vear, Felicity; Baute, Gregory; Knapp, Steven J; Vincourt, Patrick; Rieseberg, Loren H

    2013-01-01

    Long a major focus of genetic research and breeding, sunflowers (Helianthus) are emerging as an increasingly important experimental system for ecological and evolutionary studies. Here, we review the various attributes of wild and domesticated sunflowers that make them valuable for ecological experimentation and describe the numerous publicly available resources that have enabled rapid advances in ecological and evolutionary genetics. Resources include seed collections available from germplasm centres at the USDA and INRA, genomic and EST sequences, mapping populations, genetic markers, genetic and physical maps and other forward- and reverse-genetic tools. We also discuss some of the key evolutionary, genetic and ecological questions being addressed in sunflowers, as well as gaps in our knowledge and promising areas for future research. © 2012 Blackwell Publishing Ltd.

  20. Nonrandom spatial structuring of orchids in a hybrid zone of three Orchis species

    National Research Council Canada - National Science Library

    Jacquemyn, Hans; Brys, Rein; Honnay, Olivier; Roldán‐Ruiz, Isabel; Lievens, Bart; Wiegand, Thorsten

    2012-01-01

    ...‐ and interspecific interactions and heterogeneous environmental conditions. Because seed germination and establishment in orchids are critically dependent upon the availability of suitable mycorrhizal fungi, species...

  1. Spontaneous interspecific hybridization and patterns of pollen dispersal in ex situ populations of a tree species (Sinojackia xylocarpa) that is extinct in the wild.

    Science.gov (United States)

    Zhang, Jin-Ju; Ye, Qi-Gang; Yao, Xiao-Hong; Huang, Hong-Wen

    2010-02-01

    For endangered plants interspecific hybridization occurring in ex situ collections may lead to failure of reintroduction actions. We used Sinojackia xylocarpa, a well documented Chinese endemic species that is extinct in the wild, as a model case to address this concern. We used paternity analyses to assess the spontaneous hybridization and patterns of pollen flow between S. xylocarpa and its congener species, S. rehderiana, in conserved populations in Wuhan Botanic Garden. Interspecific hybridization events were detected in seven out of eight maternal trees of S. xylocarpa, and an average of 32.7% seeds collected from maternal trees of S. xylocarpa were hybrids. The paternity of 93 out of 249 seedlings from S. xylocarpa assigned to S. rehderiana provided convincing evidence that spontaneous interspecific hybridization occurred extensively in the living garden collection we studied. Different patterns of pollen dispersal (predominantly short-distance vs. long-distance pollination) were observed between intra- and interspecific hybridization events in the garden. Pollen dispersal within the ex situ populations was not restricted by distance, as evidenced by a lack of significant correlations between the average effective pollen dispersal distance (delta) and the geographic distances (d1 and d2) between maternal and paternal trees. The interspecific pollen-dispersal distance ranged from 10 to 620.1 m (mean 294.4 m). Such extensive hybridization in ex situ collections could jeopardize the genetic integrity of endangered species and irrevocably contaminate the gene pool if such hybrids are used for reintroduction and restoration. We recommend strongly that measures be taken to minimize the genetic risks of this kind of hybridization, including establishing buffer zones in ex situ collections, manipulating flowering phenology, testing seed lots before use in reintroduction programs, and controlling pollination for seed purity.

  2. Investigating Hybridization between the Two Sibling Bat Species Myotis myotis and M. blythii from Guano in a Natural Mixed Maternity Colony.

    Science.gov (United States)

    Afonso, Eve; Goydadin, Anne-Claude; Giraudoux, Patrick; Farny, Gilles

    2017-01-01

    Because they can form seasonal mixed-species groups during mating and maternal care, bats are exciting models for studying interspecific hybridization. Myotis myotis and M. blythii are genetically close and morphologically almost identical, but they differ in some aspects of their ecology and life-history traits. When they occur in sympatry, they often form large mixed maternity colonies, in which their relative abundance can vary across time due to a shift in the timing of parturition. For the first time, we used non-invasive genetic methods to assess the hybridization rate and colony composition in a maternity colony of M. myotis and M. blythii located in the French Alps. Bat guano was collected on five sampling dates spread across the roost occupancy period and was analysed for individual genotype. We investigated whether the presence of hybrids followed the pattern of one of the parental species or if it was intermediate. We identified 140 M. myotis, 12 M. blythii and 13 hybrids among 250 samples. Parental species appeared as genetically well-differentiated clusters, with an asymmetrical introgression towards M. blythii. By studying colony parameters (effective size, sex ratio and proportion of the three bat types) across the sampling dates, we found that the abundances of hybrid and M. blythii individuals were positively correlated. Our study provides a promising non-invasive method to study hybridization in bats and raises questions about the taxonomic status of the two Myotis species. We discuss the contribution of this study to the knowledge of hybrid ecology, and we make recommendations for possible future research to better understand the ecology and behaviour of hybrid individuals.

  3. Giemsa C-banding in two polyploid, South American Hordeum species, H. tetraploidum and H. lechleri, and their aneuploid hybrids with H. vulgare

    DEFF Research Database (Denmark)

    Linde-Laursen, Ib; Bothmer, R. von

    1986-01-01

    American taxa of the same sections suggest a rather close relationship and support that the biological basis for their classification with different sections is questionable. C-banding patterns identified the chromosomes of parental genomes in interspecific hybrids between the two species and H. vulgare....... The hybrids were stably aneuploid. Both had lost and acquired H. vulgare chromosomes. Thus, somatic elimination of chromosomes was combined with multiplication of chromosomes. The observations of stably aneuploid hybrids have implications for the exploitation of alien germplasm. The activity of non-H. vulgare...

  4. Impact of the Stem Borer, Dectes texanus, on Yield of the Cultivated Sunflower, Helianthus annuus.

    Science.gov (United States)

    Michaud, J.P.; Grant, Angela K.; Jyoti, J.L.

    2007-01-01

    Foliar and soil-drench insecticide treatments were used in attempts to manipulate infestation of cultivated sunflower plants, Helianthus annuus LeConte (Asterales: Asteraceae) by Dectes texanus LeConte, (Coleoptera: Cerambycidae) a serious pest of sunflowers in the High Plains of the USA. Seed yields were assessed on a per-plant basis for both oilseed and confection type sunflower hybrids in two years. Both insecticide treatments (foliar ë-cyhalothrin and soil-drench carbofuran) improved yield of oilseed sunflowers in 2004, but not in 2005. Yield of confection hybrids was improved by a systemic fungicide (thiophanate methyl) in 2005, but insecticides did not improve yield in either year. Both insecticide treatments gave good control of various stalk-boring insects such as Cylindrocopturus adspersus (Coleoptera: Curculionidae), Mordellistena sp. (Coleoptera: Mordellidae), and Pelochrista womanana (Lepidoptera: Tortricidae), but neither gave better than 50% control of D. texanus. Plants were sorted according to the presence or absence of D. texanus larvae and no reduction was found in total seed weight, seed size, or oil content as a result of infestation. However, mature larvae of D. texanus girdle stalks at the base in preparation for overwintering, a behavior that reduced stalk breakage force by 34–40%, leading to yield losses through lodging. At harvest in 2005, there were differences between cultivars and among treatments in the proportions of D. texanus larvae that had girdled their plants at harvest. It was concluded that further research aimed at reducing crop losses to D. texanus should focus on means of delaying stalk desiccation and/or deterioration, factors that appear to trigger girdling behavior. PMID:20307233

  5. DNA barcoding and microsatellites help species delimitation and hybrid identification in endangered galaxiid fishes.

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    Delphine Vanhaecke

    Full Text Available The conservation of data deficient species is often hampered by inaccurate species delimitation. The galaxiid fishes Aplochiton zebra and Aplochiton taeniatus are endemic to Patagonia (and for A. zebra the Falkland Islands, where they are threatened by invasive salmonids. Conservation of Aplochiton is complicated because species identification is hampered by the presence of resident as well as migratory ecotypes that may confound morphological discrimination. We used DNA barcoding (COI, cytochrome b and a new developed set of microsatellite markers to investigate the relationships between A. zebra and A. taeniatus and to assess their distributions and relative abundances in Chilean Patagonia and the Falkland Islands. Results from both DNA markers were 100% congruent and revealed that phenotypic misidentification was widespread, size-dependent, and highly asymmetric. While all the genetically classified A. zebra were correctly identified as such, 74% of A. taeniatus were incorrectly identified as A. zebra, the former species being more widespread than previously thought. Our results reveal, for the first time, the presence in sympatry of both species, not only in Chilean Patagonia, but also in the Falkland Islands, where A. taeniatus had not been previously described. We also found evidence of asymmetric hybridisation between female A. taeniatus and male A. zebra in areas where invasive salmonids have become widespread. Given the potential consequences that species misidentification and hybridisation can have for the conservation of these endangered species, we advocate the use of molecular markers in order to reduce epistemic uncertainty.

  6. DNA barcoding and microsatellites help species delimitation and hybrid identification in endangered galaxiid fishes.

    Science.gov (United States)

    Vanhaecke, Delphine; Garcia de Leaniz, Carlos; Gajardo, Gonzalo; Young, Kyle; Sanzana, Jose; Orellana, Gabriel; Fowler, Daniel; Howes, Paul; Monzon-Arguello, Catalina; Consuegra, Sofia

    2012-01-01

    The conservation of data deficient species is often hampered by inaccurate species delimitation. The galaxiid fishes Aplochiton zebra and Aplochiton taeniatus are endemic to Patagonia (and for A. zebra the Falkland Islands), where they are threatened by invasive salmonids. Conservation of Aplochiton is complicated because species identification is hampered by the presence of resident as well as migratory ecotypes that may confound morphological discrimination. We used DNA barcoding (COI, cytochrome b) and a new developed set of microsatellite markers to investigate the relationships between A. zebra and A. taeniatus and to assess their distributions and relative abundances in Chilean Patagonia and the Falkland Islands. Results from both DNA markers were 100% congruent and revealed that phenotypic misidentification was widespread, size-dependent, and highly asymmetric. While all the genetically classified A. zebra were correctly identified as such, 74% of A. taeniatus were incorrectly identified as A. zebra, the former species being more widespread than previously thought. Our results reveal, for the first time, the presence in sympatry of both species, not only in Chilean Patagonia, but also in the Falkland Islands, where A. taeniatus had not been previously described. We also found evidence of asymmetric hybridisation between female A. taeniatus and male A. zebra in areas where invasive salmonids have become widespread. Given the potential consequences that species misidentification and hybridisation can have for the conservation of these endangered species, we advocate the use of molecular markers in order to reduce epistemic uncertainty.

  7. Efficient cross-species capture hybridization and next-generation sequencing of mitochondrial genomes from noninvasively sampled museum specimens

    Science.gov (United States)

    Mason, Victor C.; Li, Gang; Helgen, Kristofer M.; Murphy, William J.

    2011-01-01

    The ability to uncover the phylogenetic history of recently extinct species and other species known only from archived museum material has rapidly improved due to the reduced cost and increased sequence capacity of next-generation sequencing technologies. One limitation of these approaches is the difficulty of isolating and sequencing large, orthologous DNA regions across multiple divergent species, which is exacerbated for museum specimens, where DNA quality varies greatly between samples and contamination levels are often high. Here we describe the use of cross-species DNA capture hybridization techniques and next-generation sequencing to selectively isolate and sequence partial to full-length mitochondrial DNA genomes from the degraded DNA of museum specimens, using probes generated from the DNA of a single extant species. We demonstrate our approach on specimens from an enigmatic gliding mammal, the Sunda colugo, which is widely distributed throughout Southeast Asia. We isolated DNA from 13 colugo specimens collected 47–170 years ago, and successfully captured and sequenced mitochondrial DNA from every specimen, frequently recovering fragments with 10%–13% sequence divergence from the capture probe sequence. Phylogenetic results reveal deep genetic divergence among colugos, both within and between the islands of Borneo and Java, as well as between the Malay Peninsula and different Sundaic islands. Our method is based on noninvasive sampling of minute amounts of soft tissue material from museum specimens, leaving the original specimen essentially undamaged. This approach represents a paradigm shift away from standard PCR-based approaches for accessing population genetic and phylogenomic information from poorly known and difficult-to-study species. PMID:21880778

  8. Modulation of salt (NaCl)-induced effects on oil composition and fatty acid profile of sunflower (Helianthus annuus L.) by exogenous application of salicylic acid.

    Science.gov (United States)

    Noreen, Sibgha; Ashraf, Muhammad

    2010-12-01

    Salicylic acid (SA) is a potential endogenous plant hormone that plays an important role in plant growth and development. Since sunflower yield and its seed oil yield are adversely affected by salinity, in this study the role of SA in modulating salt (NaCl)-induced effects on various yield and oil characteristics of sunflower was investigated. For this purpose a greenhouse experiment comprising two sunflower hybrid lines (Hysun-33 and SF-187), two NaCl levels (0 and 120 mmol L(-1)) and four SA levels (0, 100, 200 and 300 mg L(-1)) was conducted. Salt stress markedly reduced yield, oil content, linoleic acid and δ-tocopherol in both sunflower lines, while it increased linolenic acid, palmitic acid, stearic acid and α- and γ-tocopherols. However, increasing levels of foliar-applied SA resulted in improved achene yield and hundred-achene weight in both lines. Foliar-applied SA caused a significant decrease in oil stearic acid and α- and γ-tocopherols in both lines under non-saline and saline conditions. Salt-induced harmful effects on achene yield and oil characteristics of sunflower could be alleviated by exogenous application of SA. High doses of SA caused a marked increase in sunflower achene oil content as well as some key fatty acids. Copyright © 2010 Society of Chemical Industry.

  9. Mapping of within-species segregation distortion in Drosophila persimilis and hybrid sterility between D. persimilis and D. pseudoobscura.

    Science.gov (United States)

    McDermott, S R; Noor, M A F

    2012-10-01

    In contrast to the prevailing dogma in the 1990s, recent studies have suggested that an evolutionary history of segregation distortion within species may contribute to sterility in species hybrids. However, this recent work identified segregation distortion exclusively in species hybrids that may never have had an evolutionary history of segregation distortion in either parent species. We expand on previous work using a strain of Drosophila persimilis exhibiting segregation distortion within species to generate QTL maps for segregation distortion and hybrid sterility in crosses between D. persimilis and D. pseudoobscura. The maps localize regions along the XR contributing to both phenotypes, and they indicate one region of overlap between the two maps. This overlap could provide preliminary evidence for an association between segregation distortion within species and hybrid sterility, but the localizations are currently too broad to have confidence in this conclusion. This work is a first step towards possibly supporting a genetic conflict model of speciation in this system. © 2012 The Authors. Journal of Evolutionary Biology © 2012 European Society For Evolutionary Biology.

  10. The sunflower (Helianthus annuus L.) genome reflects a recent history of biased accumulation of transposable elements.

    Science.gov (United States)

    Staton, S Evan; Bakken, Bradley H; Blackman, Benjamin K; Chapman, Mark A; Kane, Nolan C; Tang, Shunxue; Ungerer, Mark C; Knapp, Steven J; Rieseberg, Loren H; Burke, John M

    2012-10-01

    Aside from polyploidy, transposable elements are the major drivers of genome size increases in plants. Thus, understanding the diversity and evolutionary dynamics of transposable elements in sunflower (Helianthus annuus L.), especially given its large genome size (∼3.5 Gb) and the well-documented cases of amplification of certain transposons within the genus, is of considerable importance for understanding the evolutionary history of this emerging model species. By analyzing approximately 25% of the sunflower genome from random sequence reads and assembled bacterial artificial chromosome (BAC) clones, we show that it is composed of over 81% transposable elements, 77% of which are long terminal repeat (LTR) retrotransposons. Moreover, the LTR retrotransposon fraction in BAC clones harboring genes is disproportionately composed of chromodomain-containing Gypsy LTR retrotransposons ('chromoviruses'), and the majority of the intact chromoviruses contain tandem chromodomain duplications. We show that there is a bias in the efficacy of homologous recombination in removing LTR retrotransposon DNA, thereby providing insight into the mechanisms associated with transposable element (TE) composition in the sunflower genome. We also show that the vast majority of observed LTR retrotransposon insertions have likely occurred since the origin of this species, providing further evidence that biased LTR retrotransposon activity has played a major role in shaping the chromatin and DNA landscape of the sunflower genome. Although our findings on LTR retrotransposon age and structure could be influenced by the selection of the BAC clones analyzed, a global analysis of random sequence reads indicates that the evolutionary patterns described herein apply to the sunflower genome as a whole. © 2012 The Authors. The Plant Journal © 2012 Blackwell Publishing Ltd.

  11. Contamination by Aspergillus flavus and A. fumigatus in sunflower seeds used in psittacine bird food

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    Alexsandro Machado Conceição

    2010-06-01

    Full Text Available Widely distributed in food for psittacine birds due its low price, high palatability, and cultural reasons, the Helianthus annuus, called sunflower, is proving important in clinical influenza as a result of excess calories and high incidence of contamination by some fungi, particularly Aspergillus, specifically A. flavus and A. fumigatus. The aim of this study was to evaluate the contamination by Aspergillus spp sunflower seeds for feeding psittacine birds, sold in Aracaju, Sergipe state. The tests were performed in the Laboratory of Microbiology of the Dr. Vicente Borreli Veterinary Hospital in Pio Décimo College. We evaluated four samples of sunflower seeds, soldin a municipal market and in three different supermarkets in bulk and under three bottled trademarks, processed according to Forsythe (2002. Our survey revealed a high development of A. flavus and A. fumigatus sunflower seeds. This contamination may be related to several factors such as inadequate harvest stages of drying, processing and storage of grain. Furthermore, it is important to highlight the need of a better grain storage, with controlled temperature and humidity, to reduce the possibility of contamination by Aspergillus spp. that causes injury in the feeding of psittacine birds and other animal species.

  12. Species origin of genomic factors in Nicotiana nudicaulis Watson controlling hybrid lethality in interspecific hybrids between N. nudicaulis Watson and N. tabacum L.

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    Hongshuo Liu

    Full Text Available Hybrid lethality is expressed at 28°C in the cross Nicotiana nudicaulis × N. tabacum. The S subgenome of N. tabacum has been identified as controlling this hybrid lethality. To clarify the responsible genomic factor(s of N. nudicaulis, we crossed N. trigonophylla (paternal progenitor of N. nudicaulis with N. tabacum, because hybrids between N. sylvestris (maternal progenitor of N. nudicaulis and N. tabacum are viable when grown in a greenhouse. In the cross N. trigonophylla×N. tabacum, approximately 50% of hybrids were vitrified, 20% were viable, and 20% were nonviable at 28°C. To reveal which subgenome of N. tabacum was responsible for these phenotypes, we crossed N. trigonophylla with two progenitors of N. tabacum, N. sylvestris (SS and N. tomentosiformis (TT. In the cross N. sylvestris × N. trigonophylla, we confirmed that over half of hybrids of N. sylvestris × N. trigonophylla were vitrified, and none of the hybrids of N. trigonophylla × N. tomentosiformis were. The results imply that the S subgenome, encoding a gene or genes inducing hybrid lethality in the cross between N. nudicaulis and N. tabacum, has one or more genomic factors that induce vitrification. Furthermore, in vitrified hybrids of N. trigonophylla × N. tabacum and N. sylvestris × N. trigonophylla, we found that nuclear fragmentation, which progresses during expression of hybrid lethality, was accompanied by vitrification. This observation suggests that vitrification has a relationship to hybrid lethality. Based on these results, we speculate that when N. nudicaulis was formed approximately 5 million years ago, several causative genomic factors determining phenotypes of hybrid seedlings were inherited from N. trigonophylla. Subsequently, genome downsizing and various recombination-based processes took place. Some of the causative genomic factors were lost and some became genomic factor(s controlling hybrid lethality in extant N. nudicaulis.

  13. Physical properties of sunflower grains after drying

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    Paulo Carteri Coradi

    2015-12-01

    Full Text Available The knowledge of the physical properties of the grains is important for the optimization of post-harvest operations. This study aimed to evaluate the effects of convective drying with different air temperatures (45, 55, 65 and 75 °C the physical properties of sunflower seeds. The drying sunflower grains was performed in convection oven with forced air. In natural conditions, samples of 5 kg of pellets were used for each repetition drying. During the drying process, the grains samples were weighed periodically until they reach 10% (wet basis, w.b., then were subjected to evaluations of physical properties. According to the results it was observed that the porosity, apparent density, thousand kernel weight to the drag coefficient, roundness, sphericity and width of sunflower seed did not change with increasing temperature drying air. It was concluded that the drying air temperatures of 45 °C and 55 retained the initial physical characteristics of sunflower seeds. The temperature of the drying air of 75 °C had greater influence on changes in volumetric shrinkage of the grains.

  14. Sunflower Array Antenna with Adjustable Density Taper

    NARCIS (Netherlands)

    Viganó, M.C.; Toso, G.; Caille, G.; Mangenot, C.; Lager, I.E.

    2009-01-01

    A deterministic procedure to design a nonperiodic planar array radiating a rotationally symmetric pencil beam pattern with an adjustable sidelobe level is proposed. The elements positions are derived by modifying the peculiar locations of the sunflower seeds in such a way that the corresponding

  15. Nickel remediation by AM-colonized sunflower.

    Science.gov (United States)

    Ker, Keomany; Charest, Christiane

    2010-08-01

    This greenhouse study aimed to examine the contribution of arbuscular mycorrhizal (AM) colonization on the uptake of and tolerance to nickel (Ni) in sunflower (Helianthus annuus L.). We hypothesized that AM colonization increases Ni content and tolerance in sunflower grown under varying soil Ni concentrations. The combined effect of AM colonization and soil Ni input on the assimilation of nitrogen, in particular the activity of glutamine synthetase (GS), in sunflower plants was also investigated. A factorial experimental design was performed with sunflower cv. Lemon Queen, with or without the AM fungus, Glomus intraradices Schenck & Smith, and treated with 0, 100, 200, or 400 mg Ni kg(-1) dry soil (DS). The AM colonization significantly enhanced plant growth and Ni content, especially at the lower soil Ni treatments. Furthermore, the AM plants exposed to the highest soil Ni level of 400 mg Ni kg(-1) DS had a significantly higher shoot Ni extracted percentage than non-AM plants, suggesting that the AM symbiosis contributed to Ni uptake, then its translocation from roots to shoots. The AM colonization also significantly increased the GS activity in roots, this being likely an indicator of an enhanced Ni tolerance. These findings support the hypothesis that AM symbiosis contributes to an enhanced Ni plant uptake and tolerance and should be considered as part of phytoremediation strategies.

  16. Registration of the oilseed restorer sunflower germplasms RHA 472, RHA 473, RHA 474, and RHA 475, possessing resistance to Sclerotinia head rot

    Science.gov (United States)

    The most significant disease threat to sunflower production in most of the world is Sclerotinia head rot (HR), caused by the necrotrophic pathogen Sclerotinia sclerotiorum (Lib.) de Bary. Resistance to Sclerotinia is available in some inbred lines, but no line or hybrid is immune to it and all resis...

  17. Response to salinity in the homoploid hybrid species Helianthus paradoxus and its progenitors H. annuus and H. petiolaris

    Science.gov (United States)

    Karrenberg, Sophie; Edelist, Cécile; Lexer, Christian; Rieseberg, Loren

    2008-01-01

    Summary To contribute to the understanding of ecological differentiation in speciation, we compared salinity responses of the halophytic diploid hybrid species Helianthus paradoxus and its glycophytic progenitors Helianthus annuus and Helianthus petiolaris. Plants of three populations of each species were subjected to a control (nonsaline) and three salinity treatments, including one simulating the ion composition in the habitat of H. paradoxus. Relative to the control, saline treatments led to a 17% biomass increase in H. paradoxus while its progenitors suffered 19–33% productivity reductions and only in H. paradoxus, leaf contents of potassium, calcium, and magnesium were strongly reduced. Under all treatments, H. paradoxus allocated more resources to roots, was more succulent, and had higher leaf contents of sodium (> 200 mmol l−1 tissue water) and sulfur than its progenitor species. These results suggest that salt tolerance and thus speciation of H. paradoxus is related to sodium replacing potassium, calcium and magnesium as vacuolar osmotica. The evolutionary and genetic mechanisms likely to be involved are discussed. PMID:16626481

  18. Comparative Genomic In Situ Hybridization and the Possible Role of Retroelements in the Karyotypic Evolution of Three Akodontini Species

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    Naiara Pereira Araújo

    2017-01-01

    Full Text Available South American Akodontini rodents are characterized by a large number of chromosome rearrangements. Among them, the genus Akodon has been extensively analyzed with classical and molecular cytogenetics, which allowed the identification of a large number of intra- and interspecific chromosomal variation due to Robertsonian rearrangements, pericentric inversions, and heterochromatin additions/deletions. In order to shed some light on the cause of these rearrangements, we comparatively analyzed the karyotypes of three Akodontini species, Akodon cursor (2n = 14, FN = 19, A. montensis (2n = 24, FN = 42, and Necromys lasiurus (2n = 34, FN = 34, after GTG- and CBG-banding. The karyotypes differed by Robertsonian rearrangements, pericentric inversions, centromere repositioning, and heterochromatin variation. Genome comparisons were performed through interspecific fluorescent in situ hybridization (FISH with total genomic DNAs of each species as probes (GISH. Our results revealed considerable conservation of the euchromatic portions among the three karyotypes suggesting that they mostly differ in their heterochromatic regions. FISH was also performed to assess the distribution of telomeric sequences, long and short interspersed repetitive elements (LINE-1 and B1 SINE and of the endogenous retrovirus mysTR in the genomes of the three species. The results led us to infer that transposable elements have played an important role in the enormous chromosome variation found in Akodontini.

  19. An Interval Type-2 Fuzzy System with a Species-Based Hybrid Algorithm for Nonlinear System Control Design

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    Chung-Ta Li

    2014-01-01

    Full Text Available We propose a species-based hybrid of the electromagnetism-like mechanism (EM and back-propagation algorithms (SEMBP for an interval type-2 fuzzy neural system with asymmetric membership functions (AIT2FNS design. The interval type-2 asymmetric fuzzy membership functions (IT2 AFMFs and the TSK-type consequent part are adopted to implement the network structure in AIT2FNS. In addition, the type reduction procedure is integrated into an adaptive network structure to reduce computational complexity. Hence, the AIT2FNS can enhance the approximation accuracy effectively by using less fuzzy rules. The AIT2FNS is trained by the SEMBP algorithm, which contains the steps of uniform initialization, species determination, local search, total force calculation, movement, and evaluation. It combines the advantages of EM and back-propagation (BP algorithms to attain a faster convergence and a lower computational complexity. The proposed SEMBP algorithm adopts the uniform method (which evenly scatters solution agents over the feasible solution region and the species technique to improve the algorithm’s ability to find the global optimum. Finally, two illustrative examples of nonlinear systems control are presented to demonstrate the performance and the effectiveness of the proposed AIT2FNS with the SEMBP algorithm.

  20. Are both sympatric species Ilex perado and Ilex canariensis secretly hybridizing? Indication from nuclear markers collected in Tenerife

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    Manen Jean-François

    2004-11-01

    Full Text Available Abstract Background Intra-specific and intra-individual polymorphism is frequently observed in nuclear markers of Ilex (Aquifoliaceae and discrepancy between plastid and nuclear phylogenies is the rule in this genus. These observations suggest that inter-specific plastid or/and nuclear introgression played an important role in the process of evolution of Ilex. With the aim of a precise understanding of the evolution of this genus, two distantly related sympatric species collected in Tenerife (Canary Islands, I. perado and I. canariensis, were studied in detail. Introgression between these two species was previously never reported. One plastid marker (the atpB-rbcL spacer and two nuclear markers, the ribosomal internal transcribed spacer (ITS and the nuclear encoded plastid glutamine synthetase (nepGS were analyzed for 13 and 27 individuals of I. perado and I. canariensis, respectively. Results The plastid marker is intra-specifically constant and correlated with species identity. On the other hand, whereas the nuclear markers are conserved in I. perado, they are highly polymorphic in I. canariensis. The presence of pseudogenes and recombination in ITS sequences of I. canariensis explain this polymorphism. Ancestral sequence polymorphism with incomplete lineage sorting, or past or recent hybridization with an unknown species could explain this polymorphism, not resolved by concerted evolution. However, as already reported for many other plants, past or recent introgression of an alien genotype seem the most probable explanation for such a tremendous polymorphism. Conclusions Data do not allow the determination with certitude of the putative species introgressing I. canariensis, but I. perado is suspected. The introgression would be unilateral, with I. perado as the male donor, and the paternal sequences would be rapidly converted in highly divergent and consequently unidentifiable pseudogenes. At least, this study allows the establishment of

  1. Copyrolysis of lignites and sunflower seed oil

    Energy Technology Data Exchange (ETDEWEB)

    Sait Tascy; Tuncer Erciyes; Hasancan Okutan; Ekrem Ekinci [Osmangazi University (Turkey). Department. of Chemical Engineering

    2007-07-01

    Limitation to oil yield in static atmospheres is usually experienced during pyrolysis of hydrogen deficient hydrocarbons. One way of preventing this shortage may be the use of copyrolysis operations which may, either increase the oil yield, and/or modify composition of liquid products. In this study copyrolysis of Goynuk lignite and sunflower oil has been conducted in a modified Heinze retort using 100 g sample sizes. Lignite and sunflower oil were pyrolysed separately using 5{sup o}C heating rate up to 600{sup o}C. At this final temperature the system held for 30 minutes. Using similar experimental conditions (28:72%), (50:50%) and (70:30%) sunflower oil and lignite mixtures were also copyrolysed. After the cooling operation, the tars which collected were fractionated into aliphatic, aromatic and polar fractions in a silica gel column chromatography using n-hexane, toluene and methanol. Aliphatic fractions were subjected to GC/MS analysis. The total yield and liquid yield showed a synergy for (28-72%) oil-lignite mixture whereas negative synergy was obtained for the (70-30%) oil-lignite mixture. Tars obtained from the mixtures were found to be depressed in aliphatic and aromatic fraction and promoted in polar fractions. This behaviour is explained in terms of hydrogen deficiency resulting in shortage of hydrogenation reactions. On the other hand, the abundant unsaturated oxygen containing moieties in the sunflower oil increased the polar fractions. The overwhelmingly paraffinic (69.5 %) and moderate (21.1 %) olefinic structure of the pure lignite tar was found to decrease in parrafins and increase in olephins with increasing amount of sunflower oil in the mixture. 8 refs., 5 figs., 1 tab.

  2. Sunflower seeds as eliciting agents of Compositae dermatitis.

    Science.gov (United States)

    Paulsen, Evy; El-Houri, Rime B; Andersen, Klaus E; Christensen, Lars P

    2015-03-01

    Sunflowers may cause dermatitis because of allergenic sesquiterpene lactones (SLs). Contact sensitization to sunflower seeds has also been reported, but the allergens are unknown. To analyse sunflower seeds for the presence of SLs and to assess the prevalence of sunflower sensitization in Compositae-allergic individuals. Sunflower-sensitive patients were identified by aimed patch testing. A dichloromethane extract of whole sunflower seeds was analysed by liquid chromatography-mass spectrometry and high-performance liquid chromatography. The prevalence of sensitivity to sunflower in Compositae-allergic individuals was 56%. A solvent wash of whole sunflower seeds yielded an extract containing SLs, the principal component tentatively being identified as argophyllin A or B, other SLs being present in minute amounts. The concentration of SLs on the sunflower seeds is considered high enough to elicit dermatitis in sensitive persons, and it seems appropriate to warn Compositae-allergic subjects against handling sunflower seeds. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  3. Potential of sunflower, castor bean, common buckwheat and vetiver as lead phytoaccumulators

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    Jailson do C. Alves

    2016-03-01

    Full Text Available ABSTRACT Studies concerning the tolerance, absorption and distribution of heavy metals in plants are essential for the success of phytoremediation programs. The present study was carried out in order to evaluate the potential of the sunflower, castor bean, common buckwheat and vetiver as lead phytoaccumulators. The species were grown in nutrient solution containing increasing doses of Pb (0, 50, 100, 200 and 400 mg L-1 during a 30-day exposure period. A completely randomized split-plot design was used, with a 4 x 5 factorial and three replicates. Significant reductions of dry matter of the root, shoot and whole plant were found in the all species under study as a function of the increased Pb doses. Vetiver showed higher tolerance to Pb contamination; sunflower and castor bean had intermediate tolerance and the common buckwheat proved to be the most sensitive species. The concentration and total content of Pb in plant compartments were significantly affected by the increased Pb doses in solution, and higher accumulation of this element was observed, in general, in the roots of the studied species. Common buckwheat proved to be not much promising for Pb-phytoremediation programs; sunflower showed potential for Pb phytoextraction and castor bean and vetiver were the most appropriate for Pb phytostabilization.

  4. Optimizing culture medium for meristem tissue culture of several Saccharum species and commercial hybrids

    Science.gov (United States)

    The optimal range of medium nutrients and plant growth regulators (PGR) was investigated for in vitro culture of diverse sugarcane species and cultivars. Macro-nutrients, nitrogen (N), phosphorous (P) and potassium (K), were essential for growth of leaf primordia. Although the best concentration of ...

  5. Evidence of Natural Hybridization and Introgression between Vasconcellea Species (Caricaceae) from Southern Ecuador Revealed by Chloroplast, Mitochondrial and Nuclear DNA Markers

    Science.gov (United States)

    VAN DROOGENBROECK, B.; KYNDT, T.; ROMEIJN-PEETERS, E.; VAN THUYNE, W.; GOETGHEBEUR, P.; ROMERO-MOTOCHI, J. P.; GHEYSEN, G.

    2006-01-01

    • Background and Aims Vasconcellea × heilbornii is believed to be of natural hybrid origin between V. cundinamarcensis and V. stipulata, and is often difficult to discriminate from V. stipulata on morphological grounds. The aim of this paper is to examine individuals of these three taxa and of individuals from the closely related species V. parviflora and V. weberbaueri, which all inhabit a hybrid zone in southern Ecuador. • Methods Molecular data from mitochondrial, chloroplast and nuclear DNA from 61 individuals were analysed. • Key Results Molecular analysis confirmed occasional contemporary hybridization between V. stipulata, V. cundinamarcensis and V. × heilbornii and suggested the possible involvement of V. weberbaueri in the origin of V. × heilbornii. In addition, the molecular data indicated unidirectional introgression of the V. cundinamarcensis nuclear genome into that of V. stipulata. Several of the individuals examined with morphology similar to that of V. stipulata had genetic traces of hybridization with V. cundinamarcensis, which only seems to act as pollen donor in interspecific hybridization events. Molecular analyses also strongly suggested that most of the V. × heilbornii individuals are not F1 hybrids but instead are progeny of repeated backcrosses with V. stipulata. • Conclusions The results of the present study point to the need for re-evaluation of natural populations of V. stipulata and V. × heilbornii. In general, this analysis demonstrates the complex patterns of genetic and morphological diversity found in natural plant hybrid zones. PMID:16500954

  6. Bradyrhizobia nodulating the Acacia mangium x A. auriculiformis interspecific hybrid are specific and differ from those associated with both parental species.

    Science.gov (United States)

    Le Roux, Christine; Tentchev, Diana; Prin, Yves; Goh, Doreen; Japarudin, Yani; Perrineau, Marie-Mathilde; Duponnois, Robin; Domergue, Odile; de Lajudie, Philippe; Galiana, Antoine

    2009-12-01

    In the context of an increasing utilization of the interspecific hybrid Acacia mangium x A. auriculiformis as a plantation tree in the tropical humid zone, its symbiotic characterization was carried out in comparison with that of its two parental species. Rhizobium strains of diverse geographical origins were isolated from root nodules of the hybrid and its parents. Almost all Acacia hybrid isolates were fast growing on yeast extract-mannitol medium, in contrast to those isolated from both parental species, which were mostly slow growing. The rhizobium strains were characterized through partial sequencing of the rRNA operon. In the phylogenetic tree, almost all strains isolated from the hybrid were grouped together in a clade close to Bradyrhizobium japonicum, while all strains isolated from both parental species were close to Bradyrhizobium elkanii. Inoculation experiments performed under in vitro or greenhouse conditions showed that all strains were infective with their original hosts but exhibited very variable degrees of effectivity according to the host plant tested. Thus, homologous strain-host associations were more effective than heterologous ones. This shows that there is still a high potential for isolating and testing new strains from hybrids to be used as inoculants in the context of large-scale afforestation programs.

  7. Bradyrhizobia Nodulating the Acacia mangium × A. auriculiformis Interspecific Hybrid Are Specific and Differ from Those Associated with Both Parental Species ▿ †

    Science.gov (United States)

    Le Roux, Christine; Tentchev, Diana; Prin, Yves; Goh, Doreen; Japarudin, Yani; Perrineau, Marie-Mathilde; Duponnois, Robin; Domergue, Odile; de Lajudie, Philippe; Galiana, Antoine

    2009-01-01

    In the context of an increasing utilization of the interspecific hybrid Acacia mangium × A. auriculiformis as a plantation tree in the tropical humid zone, its symbiotic characterization was carried out in comparison with that of its two parental species. Rhizobium strains of diverse geographical origins were isolated from root nodules of the hybrid and its parents. Almost all Acacia hybrid isolates were fast growing on yeast extract-mannitol medium, in contrast to those isolated from both parental species, which were mostly slow growing. The rhizobium strains were characterized through partial sequencing of the rRNA operon. In the phylogenetic tree, almost all strains isolated from the hybrid were grouped together in a clade close to Bradyrhizobium japonicum, while all strains isolated from both parental species were close to Bradyrhizobium elkanii. Inoculation experiments performed under in vitro or greenhouse conditions showed that all strains were infective with their original hosts but exhibited very variable degrees of effectivity according to the host plant tested. Thus, homologous strain-host associations were more effective than heterologous ones. This shows that there is still a high potential for isolating and testing new strains from hybrids to be used as inoculants in the context of large-scale afforestation programs. PMID:19854923

  8. Molecular cloning, phylogenetic analysis, and expression patterns of LATERAL SUPPRESSOR-LIKE and REGULATOR OF AXILLARY MERISTEM FORMATION-LIKE genes in sunflower (Helianthus annuus L.).

    Science.gov (United States)

    Fambrini, Marco; Salvini, Mariangela; Pugliesi, Claudio

    2017-03-01

    The wild sunflower (Helianthus annuus) plants develop a highly branched form with numerous small flowering heads. The origin of a no branched sunflower, producing a single large head, has been a key event in the domestication process of this species. The interaction between hormonal factors and several genes organizes the initiation and outgrowth of axillary meristems (AMs). From sunflower, we have isolated two genes putatively involved in this process, LATERAL SUPPRESSOR (LS)-LIKE (Ha-LSL) and REGULATOR OF AXILLARY MERISTEM FORMATION (ROX)-LIKE (Ha-ROXL), encoding for a GRAS and a bHLH transcription factor (TF), respectively. Typical amino acid residues and phylogenetic analyses suggest that Ha-LSL and Ha-ROXL are the orthologs of the branching regulator LS and ROX/LAX1, involved in the growth habit of both dicot and monocot species. qRT-PCR analyses revealed a high accumulation of Ha-LSL transcripts in roots, vegetative shoots, and inflorescence shoots. By contrast, in internodal stems and young leaves, a lower amount of Ha-LSL transcripts was observed. A comparison of transcription patterns between Ha-LSL and Ha-ROXL revealed some analogies but also remarkable differences; in fact, the gene Ha-ROXL displayed a low expression level in all organs analyzed. In situ hybridization (ISH) analysis showed that Ha-ROXL transcription was strongly restricted to a small domain within the boundary zone separating the shoot apical meristem (SAM) and the leaf primordia and in restricted regions of the inflorescence meristem, beforehand the separation of floral bracts from disc flower primordia. These results suggested that Ha-ROXL may be involved to establish a cell niche for the initiation of AMs as well as flower primordia. The accumulation of Ha-LSL transcripts was not restricted to the boundary zones in vegetative and inflorescence shoots, but the mRNA activity was expanded in other cellular domains of primary shoot apical meristem as well as AMs. In addition, Ha

  9. Hybridization of Phenylthiolate- and Methylthiolate-Adatom Species at Low Coverage on the Au(111) Surface

    Science.gov (United States)

    2013-03-07

    thiolate species, methylthiolate and phenylthiolate, on the Au(111) surface. Despite the apparent stability, organometallic complexes of methyl- and...stability, organometallic complexes of methyl- and phenylthiolate with the goldadatom (RS?Au?SR, with R as the hydrocarbon group) undergo a stoichiometric...Electrical and Computer Engineering, University of Toronto, Toronto, ON, M5S 3G4, Canada ∥Department of Chemistry , University of Virginia, Charlottesville

  10. Growth under elevated atmospheric CO(2) concentration accelerates leaf senescence in sunflower (Helianthus annuus L.) plants.

    Science.gov (United States)

    de la Mata, Lourdes; Cabello, Purificación; de la Haba, Purificación; Agüera, Eloísa

    2012-09-15

    Some morphogenetic and metabolic processes were sensitive to a high atmospheric CO(2) concentration during sunflower primary leaf ontogeny. Young leaves of sunflower plants growing under elevated CO(2) concentration exhibited increased growth, as reflected by the high specific leaf mass referred to as dry weight in young leaves (16 days). The content of photosynthetic pigments decreased with leaf development, especially in plants grown under elevated CO(2) concentrations, suggesting that high CO(2) accelerates chlorophyll degradation, and also possibly leaf senescence. Elevated CO(2) concentration increased the oxidative stress in sunflower plants by increasing H(2)O(2) levels and decreasing activity of antioxidant enzymes such as catalase and ascorbate peroxidase. The loss of plant defenses probably increases the concentration of reactive oxygen species in the chloroplast, decreasing the photosynthetic pigment content as a result. Elevated CO(2) concentration was found to boost photosynthetic CO(2) fixation, especially in young leaves. High CO(2) also increased the starch and soluble sugar contents (glucose and fructose) and the C/N ratio during sunflower primary leaf development. At the beginning of senescence, we observed a strong increase in the hexoses to sucrose ratio that was especially marked at high CO(2) concentration. These results indicate that elevated CO(2) concentration could promote leaf senescence in sunflower plants by affecting the soluble sugar levels, the C/N ratio and the oxidative status during leaf ontogeny. It is likely that systemic signals produced in plants grown with elevated CO(2), lead to early senescence and a higher oxidation state of the cells of these plant leaves. Copyright © 2012 Elsevier GmbH. All rights reserved.

  11. Bacillus depressus sp. nov., isolated from soil of a sunflower field.

    Science.gov (United States)

    Wei, Xuexin; Xin, Di; Xin, Yuhua; Zhang, Hao; Wang, Tianying; Zhang, Jianli

    2016-01-01

    A Gram-stain positive, rod-shaped, endospore-forming and aerobic bacterium, designated BZ1(T), was isolated from a soil sample collected from a sunflower field in Wuyuan county, Inner Mongolia, China. On the basis of 16S rRNA gene sequence analysis, the isolate was found to be a member of the genus Bacillus and the close phylogenetic relatives to be Bacillus gottheilii WCC 4585(T), Bacillus oceanisediminis H2(T), Bacillus mesonae FJAT-13985(T) and Bacillus horneckiae DSM 23495(T) with 98.3, 98.1, 98.0 and 97.6 % sequence similarity, respectively. Strain BZ1(T) was found to grow at 6-40 °C (optimum 30-33 °C), pH 6.0-9.0 (optimum pH 7.0) and 0-5.5 % (w/v) NaCl (optimum 0.5 %). The cell wall diamino acid of the peptidoglycan of strain BZ1(T) was identified as meso-diaminopimelic acid and the predominant respiratory quinone as MK-7. The major cellular fatty acids were found to be iso-C15:0, anteiso-C15:0 and iso-C14:0, and the polar lipids to consist of diphosphatidylglycerol, phosphatidylglycerol and phosphatidylethanolamine. The novel strain was found to have a DNA G + C content 44.5 mol%. DNA-DNA hybridization with closely related strains was low. Based on phenotypic, phylogenetic and chemotaxonomic results, it is concluded that strain BZ1(T) represents a novel species within the genus Bacillus, for which we propose the name Bacillus depressus sp. nov. The type strain is BZ1(T) (= CGMCC 1.15124(T) = KCTC 33643(T)).

  12. Simultaneous visualization of different genomes (J, JSt and St) in a Thinopyrum intermedium × Thinopyrum ponticum synthetic hybrid (Poaceae) and in its parental species by multicolour genomic in situ hybridization (mcGISH).

    Science.gov (United States)

    Kruppa, Klaudia; Molnár-Láng, Márta

    2016-01-01

    Multicolour genomic in situ hybridization (mcGISH) using total genomic DNA probes from Thinopyrum bessarabicum (Săvulescu & Rayss, 1923) Á. Löve, 1984 (genome J(b) or E(b), 2n = 14), and Pseudoroegneria spicata (Pursh, 1814) Á. Löve, 1980 (genome St, 2n = 14) was used to characterize the mitotic metaphase chromosomes of a synthetic hybrid of Thinopyrum intermedium (Host, 1805) Barkworth & D.R. Dewey, 1985 and Thinopyrum ponticum (Podpěra, 1902) Z.-W. Liu et R.-C.Wang, 1993 named "Agropyron glael" and produced by N.V. Tsitsin in the former Soviet Union. The mcGISH pattern of this synthetic hybrid was compared to its parental wheatgrass species. Hexaploid Thinopyrum intermedium contained 19 J, 9 J(St) and 14 St chromosomes. The three analysed Thinopyrum ponticum accessions had different chromosome compositions: 43 J + 27 J(St) (PI531737), 40 J + 30 J(St) (VIR-44486) and 38 J + 32 J(St) (D-3494). The synthetic hybrid carried 18 J, 28 J(St) and 8 St chromosomes, including one pair of J-St translocation and/or decreased fluorescent intensity, resulting in unique hybridization patterns. Wheat line Mv9kr1 was crossed with the Thinopyrum intermedium × Thinopyrum ponticum synthetic hybrid in Hungary in order to transfer its advantageous agronomic traits (leaf rust and yellow rust resistance) into wheat. The chromosome composition of a wheat/A.glael F1 hybrid was 21 wheat + 28 wheatgrass (11 J + 14 J(St)+ 3 S). In the present study, mcGISH involving the simultaneous use of St and J genomic DNA as probes provided information about the type of Thinopyrum chromosomes in a Thinopyrum intermedium/Thinopyrum ponticum synthetic hybrid called A. glael.

  13. Exogenous sodium sulfide improves morphological and physiological responses of a hybrid Populus species to nitrogen dioxide.

    Science.gov (United States)

    Hu, Yanbo; Bellaloui, Nacer; Sun, Guangyu; Tigabu, Mulualem; Wang, Jinghong

    2014-06-15

    Gaseous nitrogen dioxide (NO2) can disturb normal plant growth and trigger complex physiological responses. NO2-induced responses are influenced by biotic or abiotic factors. In this study, we investigated the effects of exogenous sodium sulfide (Na2S, 5mmolL(-1)) on epidermis and stomata related physico-chemical responses of hybrid poplar cuttings (Pouplus alba×P. berolinensis) to gaseous NO2 (4μl1(-1)) for three time periods (0, 14 and 48h). We also investigated hydrogen sulfide (H2S), nitrate-nitrogen and nitrate reductase activity (NR) in control and Na2S treated plants. Our results showed that NO2 exposure for 48h led to the decline of NR, maximal PSII quantum yield (Fv/Fm), net photosynthetic rate (Pn), and dark respiration rate (Rd). The maximum rate for the post-illumination carbon dioxide burst (PIB) occurred in 48-h exposed leaves 13-15s after darkening. Moreover, NO2 exposure resulted in a significant increase in nitrogen percentage (from 0 to 33%) and a decrease in the macro and micro-elements of leaf surface. Spraying Na2S aqueous solution on the leaf surfaces significantly increased the thicknesses of palisade/spongy tissue and H2S content. Na2S pretreatment alleviated NO2-caused toxic effects as indicated by increased NR and higher values of Pn, Fv/Fm, and actual photochemical efficiency in light (ФPSII) compared with the control. Na2S pretreatment had no significant impacts on PIB-based photorespiration or elements composition of a leaf surface. Copyright © 2013 Elsevier GmbH. All rights reserved.

  14. Damage by the Sitka spruce weevil (Pissodes strobi) and growth patterns for 10 spruce species and hybrids over 26 years in the Pacific Northwest.

    Science.gov (United States)

    Russel G. Mitchell; Kenneth H. Wright; Norman E. Johnson

    1990-01-01

    Ten species and hybrids of spruce (Picea spp.) were planted and observed annually for 26 years at three coastal locations in Oregon and Washington to evaluate growth rates and susceptibility to the Sitka spruce weevil (= white pine weevil), Pissodes strobi The 10 spruce were: Sitka spruce, Norway spruce, Lutz spruce, black...

  15. Discriminating multi-species populations in biofilms with peptide nucleic acid fluorescence in situ hybridization (PNA FISH).

    Science.gov (United States)

    Almeida, Carina; Azevedo, Nuno F; Santos, Sílvio; Keevil, Charles W; Vieira, Maria J

    2011-03-29

    Our current understanding of biofilms indicates that these structures are typically composed of many different microbial species. However, the lack of reliable techniques for the discrimination of each population has meant that studies focusing on multi-species biofilms are scarce and typically generate qualitative rather than quantitative data. We employ peptide nucleic acid fluorescence in situ hybridization (PNA FISH) methods to quantify and visualize mixed biofilm populations. As a case study, we present the characterization of Salmonella enterica/Listeria monocytogenes/Escherichia coli single, dual and tri-species biofilms in seven different support materials. Ex-situ, we were able to monitor quantitatively the populations of ∼56 mixed species biofilms up to 48 h, regardless of the support material. In situ, a correct quantification remained more elusive, but a qualitative understanding of biofilm structure and composition is clearly possible by confocal laser scanning microscopy (CLSM) at least up to 192 h. Combining the data obtained from PNA FISH/CLSM with data from other established techniques and from calculated microbial parameters, we were able to develop a model for this tri-species biofilm. The higher growth rate and exopolymer production ability of E. coli probably led this microorganism to outcompete the other two [average cell numbers (cells/cm(2)) for 48 h biofilm: E. coli 2,1 × 10(8) (± 2,4 × 10(7)); L. monocytogenes 6,8 × 10(7) (± 9,4 × 10(6)); and S. enterica 1,4 × 10(6) (± 4,1 × 10(5))]. This overgrowth was confirmed by CSLM, with two well-defined layers being easily identified: the top one with E. coli, and the bottom one with mixed regions of L. monocytogenes and S. enterica. While PNA FISH has been described previously for the qualitative study of biofilm populations, the present investigation demonstrates that it can also be used for the accurate quantification and spatial distribution of species in polymicrobial communities

  16. Correlation and path analysis of yield and yield components of confectionary sunflower

    Directory of Open Access Journals (Sweden)

    Hladni Nada

    2016-01-01

    Full Text Available Path coefficient analysis was applied to gain information on direct and indirect effects of studied traits (seed oil content, kernel oil content, seed protein content, kernel protein content, head diameter, kernel ratio and plant height on sunflower seed yield. Traits which exhibit the highest effects on seed yield will be used as a selection criterion in confectionary sunflower breeding. The research was conducted during three vegetation seasons on 22 experimental confectionary sunflower hybrids, created in breeding program the Institute of Field and Vegetable Crops. Among the largest number of examined traits, significant and highly significant correlations were found. With the analysis of simple correlation coefficients a low interdependence was determined between, kernel protein content, plant heights with seed yield. Negative but weak correlation was determined between kernel oil content, seed protein content, kernel ratio with seed yield. Established a negative strong correlation of head diameter (-0.190* and negative very strong correlation of seed oil content (-0.351** with seed yield. The seed oil content had a very strong direct negative effect on seed yield (DE=-0.831**. The head diameter, plant height, seed protein content had weak negative direct effect on seed yield. Kernel protein content and kernel oil content has demonstrated a weak direct positive effect on seed yield. Path coefficient analysis for seed yield showed very strong direct effect for kernel ratio (DE=0.487* on seed yield, it shows that the kernel ratio is important selection criterion for confectionary sunflower breeding. [Projekat Ministarstva nauke Republike Srbije, br. 31025: Development of new varieties and production technology improvement of oil crops for different purposes

  17. Expressed Sequence Tags from the oomycete Plasmopara halstedii, an obligate parasite of the sunflower

    Directory of Open Access Journals (Sweden)

    Mouzeyar Said

    2007-12-01

    Full Text Available Abstract Background Sunflower downy mildew is a major disease caused by the obligatory biotrophic oomycete Plasmopara halstedii. Little is known about the molecular mechanisms underlying its pathogenicity. In this study we used a genomics approach to gain a first insight into the transcriptome of P. halstedii. Results To identify genes from the obligatory biotrophic oomycete Plasmopara halstedii that are expressed during infection in sunflower (Helianthus annuus L. we employed the suppression subtraction hybridization (SSH method from sunflower seedlings infected by P. halstedii. Using this method and random sequencing of clones, a total of 602 expressed sequence tags (ESTs corresponding to 230 unique sequence sets were identified. To determine the origin of the unisequences, PCR primers were designed to amplify these gene fragments from genomic DNA isolated either from P. halstedii sporangia or from Helianthus annuus. Only 145 nonredundant ESTs which correspond to a total of 373 ESTs (67.7% proved to be derived from P. halstedii genes and that are expressed during infection in sunflower. A set of 87 nonredundant sequences were identified as showing matches to sequences deposited in public databases. Nevertheless, about 7% of the ESTs seem to be unique to P. halstedii without any homolog in any public database. Conclusion A summary of the assignment of nonredundant ESTs to functional categories as well as their relative abundance is listed and discussed. Annotation of the ESTs revealed a number of genes that could function in virulence. We provide a first glimpse into the gene content of P. halstedii. These resources should accelerate research on this important pathogen.

  18. Intramolecular transesterification of glycerides during the hydrogenation of sunflower oil

    National Research Council Canada - National Science Library

    Tyutyunnikov, B.N; Mastruk, M.S

    1972-01-01

    The intramolecular transesterification of glycerides, the migration of the acyls of fatty acids between positions within the same glyceride molecule, was traced during the hydrogenation of sunflower...

  19. Chemical changes in sunflower silage associated with different additives

    OpenAIRE

    Goes,Rafael Henrique de Tonissi e Buschinelli de; Miyagi,Eliane Sayuri; Oliveira,Euclides Reuter de; Brabes,Kelly Cristina da Silva; Patussi,Rosielen Augusto; Dambrós,Carlos Eduardo

    2013-01-01

    Thirty-six experimental silos arranged in a completely randomized 4 x 3 factorial design were provided to evaluate the chemical changes of sunflower silage treated with soybean hulls, sunflower crushed and urea at 14, 21 and 28 days of ensilage. The additives were based on 5% natural matter, whereas control consisted of silage with 100% sunflower plant. OM, NDIP, and MM had average rates 911.2; 86.6 and 92.9 g kg-1 of dry matter respectively. The addition of soybean hulls and sunflower crushe...

  20. Meristem transformation of sunflower via Agrobacterium.

    Science.gov (United States)

    Schrammeijer, B; Sijmons, P C; van den Elzen, P J; Hoekema, A

    1990-07-01

    For transformation of sunflower (Helianthus annuus L. cv. Zebulon), shoot apical meristems were dissected from seeds and cocultivated with a disarmed Agrobacterium tumefaciens strain harboring a binary vector carrying genes encoding GUS- and NPTII-activity. The influence of the media conditions, the time of cocultivation and the stage of the developing seed on shoot development and meristem transformation was analysed. Transformants were selected by their ability to grow on kanamycin. Transformation was confirmed by assays for GUS and NPTII. GUS-positive shoots were rooted on rockwool and transferred to soil. Transformation of shoot meristem cells occurred at low frequencies. Chimaeric expression of the two genes was observed in transformed plants. Integration of the foreign DNA in the sunflower genome was confirmed with the polymerase chain reaction.

  1. Physical properties of sunflower seeds during drying

    Directory of Open Access Journals (Sweden)

    Thaís Adriana de Souza Smaniotto

    2017-03-01

    Full Text Available The aim of this work was to determine the effect that the moisture content has on the physical properties of sunflower seeds. The cultivar Olisun 3, with an initial moisture content of 34.1 (% wb, was used and then subjected to drying in an oven with forced air ventilation under three temperature conditions: 40, 60 and 80 °C. The reduction in the moisture content during drying was monitored by the gravimetric method until it reached a final moisture content of 8.0 ± 1.0 (% wb. The physical properties were analysed: the bulk density, true density, intergranular porosity and volumetric shrinkage of the mass and unit and terminal velocity. The reduction in the moisture content influenced the physical properties of sunflower seeds and caused a decrease in the intergranular porosity, bulk density and true density at all examined temperatures. The mass and volumetric contractions of the unit and reduction in shrinkage rates all increased with the drying of sunflower seeds at all studied temperatures. The terminal velocity increased as the moisture content of the grains increased, which was more evident at the drying temperature of 80 °C.

  2. Considerations concerning a new sunflower oil plant

    Energy Technology Data Exchange (ETDEWEB)

    Ruckenstein, C.

    1982-01-01

    The turn-key project to process sunflower seed is described in detail. This factory will process decorticated sunflower seed which ensures meal with higher protein content (40-42%). The hulls from the decortication will be burned to produce 35 tons steam per hour. Quantities of hulls left over can be pelleted. Unloading section of the plant is designed for 300 tons per hour. The drying section for the first stage is foreseen for 100 tons per hour drying the seeds from 16% to 10% moisture. In the factory there is a second-stage dryer before decortication bringing the moisture in the seeds from 10% down to 8%. The basic technological process consists of cleaning, decortication, preparation, pre-pressing, extraction, and meal treatment. Meal can be sold in bulk or pelleted. The factory is designed for the actual sunflower seed from North Dakota with an average oil content of 40%. In a few years this content will be increased to 45%.

  3. Hybridization, natural selection, and evolution of reproductive isolation: a 25-years survey of an artificial sympatric area between two mosquito sibling species of the Aedes mariae complex.

    Science.gov (United States)

    Urbanelli, Sandra; Porretta, Daniele; Mastrantonio, Valentina; Bellini, Romeo; Pieraccini, Giuseppe; Romoli, Riccardo; Crasta, Graziano; Nascetti, Giuseppe

    2014-10-01

    Natural selection can act against maladaptive hybridization between co-occurring divergent populations leading to evolution of reproductive isolation among them. A critical unanswered question about this process that provides a basis for the theory of speciation by reinforcement, is whether natural selection can cause hybridization rates to evolve to zero. Here, we investigated this issue in two sibling mosquitoes species, Aedes mariae and Aedes zammitii, that show postmating reproductive isolation (F1 males sterile) and partial premating isolation (different height of mating swarms) that could be reinforced by natural selection against hybridization. In 1986, we created an artificial sympatric area between the two species and sampled about 20,000 individuals over the following 25 years. Between 1986 and 2011, the composition of mating swarms and the hybridization rate between the two species were investigated across time in the sympatric area. Our results showed that A. mariae and A. zammitii have not completed reproductive isolation since their first contact in the artificial sympatric area. We have discussed the relative role of factors such as time of contact, gene flow, strength of natural selection, and biological mechanisms causing prezygotic isolation to explain the observed results. © 2014 The Author(s). Evolution © 2014 The Society for the Study of Evolution.

  4. Craniofacial shape transition across the house mouse hybrid zone: implications for the genetic architecture and evolution of between-species differences.

    Science.gov (United States)

    Pallares, Luisa F; Turner, Leslie M; Tautz, Diethard

    2016-06-01

    Craniofacial shape differences between taxa have often been linked to environmental adaptation, e.g., new food sources, or have been studied in the context of domestication. Evidence for the genetic basis of such phenotypic differences to date suggests that between-species as well as between-population variation has an oligogenic basis, i.e., few loci of large effect explain most of the variation. In mice, it has been shown that within-population craniofacial variation has a highly polygenic basis, but there are no data regarding the genetic basis of between-species differences in natural populations. Here, we address this question using a phenotype-focused approach. Using 3D geometric morphometrics, we phenotyped a panel of mice derived from a natural hybrid zone between Mus musculus domesticus and Mus mus musculus and quantify the transition of craniofacial shape along the hybridization gradient. We find a continuous shape transition along the hybridization gradient and unaltered developmental stability associated with hybridization. This suggests that the morphospace between the two subspecies is continuous despite reproductive isolation and strong barriers to gene flow. We show that quantitative changes in overall genome composition generate quantitative changes in craniofacial shape; this supports a highly polygenic basis for between-species craniofacial differences in the house mouse. We discuss our findings in the context of oligogenic versus polygenic models of the genetic architecture of morphological traits.

  5. Sequencing wild and cultivated cassava and related species reveals extensive interspecific hybridization and genetic diversity.

    Science.gov (United States)

    Bredeson, Jessen V; Lyons, Jessica B; Prochnik, Simon E; Wu, G Albert; Ha, Cindy M; Edsinger-Gonzales, Eric; Grimwood, Jane; Schmutz, Jeremy; Rabbi, Ismail Y; Egesi, Chiedozie; Nauluvula, Poasa; Lebot, Vincent; Ndunguru, Joseph; Mkamilo, Geoffrey; Bart, Rebecca S; Setter, Tim L; Gleadow, Roslyn M; Kulakow, Peter; Ferguson, Morag E; Rounsley, Steve; Rokhsar, Daniel S

    2016-05-01

    Cassava (Manihot esculenta) provides calories and nutrition for more than half a billion people. It was domesticated by native Amazonian peoples through cultivation of the wild progenitor M. esculenta ssp. flabellifolia and is now grown in tropical regions worldwide. Here we provide a high-quality genome assembly for cassava with improved contiguity, linkage, and completeness; almost 97% of genes are anchored to chromosomes. We find that paleotetraploidy in cassava is shared with the related rubber tree Hevea, providing a resource for comparative studies. We also sequence a global collection of 58 Manihot accessions, including cultivated and wild cassava accessions and related species such as Ceará or India rubber (M. glaziovii), and genotype 268 African cassava varieties. We find widespread interspecific admixture, and detect the genetic signature of past cassava breeding programs. As a clonally propagated crop, cassava is especially vulnerable to pathogens and abiotic stresses. This genomic resource will inform future genome-enabled breeding efforts to improve this staple crop.

  6. The plant pathogen Phytophthora andina emerged via hybridization of an unknown Phytophthora species and the Irish potato famine pathogen, P. infestans.

    Science.gov (United States)

    Goss, Erica M; Cardenas, Martha E; Myers, Kevin; Forbes, Gregory A; Fry, William E; Restrepo, Silvia; Grünwald, Niklaus J

    2011-01-01

    Emerging plant pathogens have largely been a consequence of the movement of pathogens to new geographic regions. Another documented mechanism for the emergence of plant pathogens is hybridization between individuals of different species or subspecies, which may allow rapid evolution and adaptation to new hosts or environments. Hybrid plant pathogens have traditionally been difficult to detect or confirm, but the increasing ease of cloning and sequencing PCR products now makes the identification of species that consistently have genes or alleles with phylogenetically divergent origins relatively straightforward. We investigated the genetic origin of Phytophthora andina, an increasingly common pathogen of Andean crops Solanum betaceum, S. muricatum, S. quitoense, and several wild Solanum spp. It has been hypothesized that P. andina is a hybrid between the potato late blight pathogen P. infestans and another Phytophthora species. We tested this hypothesis by cloning four nuclear loci to obtain haplotypes and using these loci to infer the phylogenetic relationships of P. andina to P. infestans and other related species. Sequencing of cloned PCR products in every case revealed two distinct haplotypes for each locus in P. andina, such that each isolate had one allele derived from a P. infestans parent and a second divergent allele derived from an unknown species that is closely related but distinct from P. infestans, P. mirabilis, and P. ipomoeae. To the best of our knowledge, the unknown parent has not yet been collected. We also observed sequence polymorphism among P. andina isolates at three of the four loci, many of which segregate between previously described P. andina clonal lineages. These results provide strong support that P. andina emerged via hybridization between P. infestans and another unknown Phytophthora species also belonging to Phytophthora clade 1c.

  7. The plant pathogen Phytophthora andina emerged via hybridization of an unknown Phytophthora species and the Irish potato famine pathogen, P. infestans.

    Directory of Open Access Journals (Sweden)

    Erica M Goss

    Full Text Available Emerging plant pathogens have largely been a consequence of the movement of pathogens to new geographic regions. Another documented mechanism for the emergence of plant pathogens is hybridization between individuals of different species or subspecies, which may allow rapid evolution and adaptation to new hosts or environments. Hybrid plant pathogens have traditionally been difficult to detect or confirm, but the increasing ease of cloning and sequencing PCR products now makes the identification of species that consistently have genes or alleles with phylogenetically divergent origins relatively straightforward. We investigated the genetic origin of Phytophthora andina, an increasingly common pathogen of Andean crops Solanum betaceum, S. muricatum, S. quitoense, and several wild Solanum spp. It has been hypothesized that P. andina is a hybrid between the potato late blight pathogen P. infestans and another Phytophthora species. We tested this hypothesis by cloning four nuclear loci to obtain haplotypes and using these loci to infer the phylogenetic relationships of P. andina to P. infestans and other related species. Sequencing of cloned PCR products in every case revealed two distinct haplotypes for each locus in P. andina, such that each isolate had one allele derived from a P. infestans parent and a second divergent allele derived from an unknown species that is closely related but distinct from P. infestans, P. mirabilis, and P. ipomoeae. To the best of our knowledge, the unknown parent has not yet been collected. We also observed sequence polymorphism among P. andina isolates at three of the four loci, many of which segregate between previously described P. andina clonal lineages. These results provide strong support that P. andina emerged via hybridization between P. infestans and another unknown Phytophthora species also belonging to Phytophthora clade 1c.

  8. Lipid, polyamide, and flavonol phagostimulants for adult western corn rootworm from sunflower (Helianthus annuus L.) pollen.

    Science.gov (United States)

    Lin, S; Mullin, C A

    1999-03-01

    Adult Diabroticites including western corn rootworm (WCR), Diabrotica virgifera virgifera LeConte, consume pollen of corn, squash, sunflower, and other species. Short-chain neutral amino acids in methanol-water extracts of pollen have been previously identified in our laboratory as strong phagostimulants for Diabrotica. Bioassay-driven fractionation was used to characterize the interacting lipid and midpolarity phagostimulants for adult WCR in Giant Gray Stripe sunflower, Helianthus annuus L., pollen. Lipids rich in omega3-linolenic acid including triglycerides, free fatty acids, phosphatidylethanolamines, phosphatidic acids, and phosphatidylcholines were highly phagostimulatory. Other important phagostimulatory components included a hydroxycinnamic acid-polyamine amide, N(1),N(5),N(10)-tri[(E)-p-coumaroyl]spermidine, and a flavonol, quercetin beta-3-O-glucoside. The structural characteristics of these phagoactive compounds and their role in the pollinivory specialization of rootworm beetles are discussed.

  9. Tyrosine nitration provokes inhibition of sunflower carbonic anhydrase (β-CA) activity under high temperature stress.

    Science.gov (United States)

    Chaki, Mounira; Carreras, Alfonso; López-Jaramillo, Javier; Begara-Morales, Juan C; Sánchez-Calvo, Beatriz; Valderrama, Raquel; Corpas, Francisco J; Barroso, Juan B

    2013-02-28

    Protein tyrosine nitration is a post-translational modification (PTM) mediated by reactive nitrogen species (RNS) and it is a new area of research in higher plants. Previously, it was demonstrated that the exposition of sunflower (Helianthus annuus L.) seedlings to high temperature (HT) caused both oxidative and nitrosative stress. The nitroproteome analysis under this stress condition showed the induction of 13 tyrosine-nitrated proteins being the carbonic anhydrase (CA) one of these proteins. The analysis of CA activity under high temperature showed that this stress inhibited the CA activity by a 43%. To evaluate the effect of nitration on the CA activity in sunflower it was used 3-morpholinosydnonimine (SIN-1) (peroxynitrite donor) as the nitrating agent. Thus the CA activity was inhibited by 41%. In silico analysis of the pea CA protein sequence suggests that Tyr(205) is the most likely potential target for nitration. Copyright © 2012 Elsevier Inc. All rights reserved.

  10. Hybrid TiO2 -Ruthenium Nano-photosensitizer Synergistically Produces Reactive Oxygen Species in both Hypoxic and Normoxic Conditions.

    Science.gov (United States)

    Gilson, Rebecca C; Black, Kvar C L; Lane, Daniel D; Achilefu, Samuel

    2017-08-28

    Photodynamic therapy (PDT) is widely used to treat diverse diseases, but its dependence on oxygen to produce cytotoxic reactive oxygen species (ROS) diminishes the therapeutic effect in a hypoxic environment, such as solid tumors. Herein, we developed a ROS-producing hybrid nanoparticle-based photosensitizer capable of maintaining high levels of ROS under both normoxic and hypoxic conditions. Conjugation of a ruthenium complex (N3) to a TiO2 nanoparticle afforded TiO2 -N3. Upon exposure of TiO2 -N3 to light, the N3 injected electrons into TiO2 to produce three- and four-fold more hydroxyl radicals and hydrogen peroxide, respectively, than TiO2 at 160 mmHg. TiO2 -N3 maintained three-fold higher hydroxyl radicals than TiO2 under hypoxic conditions via N3-facilitated electron-hole reduction of adsorbed water molecules. The incorporation of N3 transformed TiO2 from a dual type I and II PDT agent to a predominantly type I photosensitizer, irrespective of the oxygen content. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  11. Differences in the glucose and fructose consumption profiles in diverse Saccharomyces wine species and their hybrids during grape juice fermentation.

    Science.gov (United States)

    Tronchoni, Jordi; Gamero, Amparo; Arroyo-López, Francisco Noé; Barrio, Eladio; Querol, Amparo

    2009-09-15

    Yeasts with a high fructose consumption capability are very important for winemakers to solve problems associated with sluggish or stuck fermentations causing undesirable sweetness in wines. In the present study, we analyze the kinetics of glucose and fructose consumption during wine fermentations performed at low (12 degrees C) and high (28 degrees C) temperatures by twelve different yeast strains belonging to the species Saccharomyces cerevisiae, S. bayanus var. uvarum, S. kudriavzevii as well as interspecific Saccharomyces hybrids. Different mathematical equations (sigmoid, exponential and linear decay functions) were used to fit, by means of linear and nonlinear regressions, the sugar degradation along the fermentative process. Temperature had an important influence on glucose and fructose consumption, and clearly different degradation profiles were observed at 12 and 28 degrees C. From the obtained equations, times to consume half and total of the initial glucose and fructose concentrations present in the must were calculated, allowing a quantitative comparison among yeasts in order to select the fastest fermentative yeast according to the fermentation temperature. In general, all yeasts assayed showed a slightly higher preference for glucose than fructose at both temperatures, confirming the glucophilic character of Saccharomyces wine yeasts. However, at low temperatures, some Saccharomyces yeasts showed a fructophilic character at the beginning of fermentation. This kind of studies can be very useful for the wine industry to select yeast strains with different glucose/fructose preferences.

  12. 15e CONFERENCE INTERNATIONALE TOURNESOL Sunflower ecophysiology: some unresolved issues*

    Directory of Open Access Journals (Sweden)

    Hall Antonio J.

    2001-01-01

    Full Text Available Major unresolved issues in sunflower ecophysiology constrain efforts to improve crop modelling, management, genetic analysis and breeding. Three issues are used here to illustrate this point. Firstly, much of the work on the duration of the emergence to flowering phase has considered the phase as a whole. It is argued that a more detailed analysis based on sub-phases is required, particularly in view of possible intraspecific variability in the durations of the basic vegetative and juvenile phases and evidence that photoperiod responses before, during and after floral initiation may differ between genotypes and even be of opposite sign for the same genotype. Secondly,contrasting responses of grain oil proportion to manipulation of plant population density and incident radiation appear to be linked to variations in kernel oil proportion rather than to kernel: hull ratio, and responses of grain oil proportion to changes in sowing date seem to have a similar origin. More effort should be focused on understanding the controls of oil mass per kernel. It is speculated that there may be a genotype-dependent limit to this variable. A third unresolved issue relates to the nature and strength of the linkage between post-anthesis stay-green and leaf photosynthetic functionality. These variables are poorly related during pre-anthesis senescence of leaves in the lower portion of closed canopies, and for sunflower this linkage appears much weaker than in other crop species. Current interest in post-anthesis stay-green as a possibly useful crop attribute requires clarification of this uncertainty.

  13. "Fix Me Another Marguerite!": Species delimitation in a group of intensively hybridizing lineages of ox-eye daisies (Leucanthemum Mill., Compositae-Anthemideae).

    Science.gov (United States)

    Wagner, Florian; Härtl, Sabine; Vogt, Robert; Oberprieler, Christoph

    2017-08-01

    Delineating species boundaries in the framework of the multi-species coalescent (MSC) proves to be a reliable, objective, and reproducible method in an increasing number of studies. However, the underlying model assumes the lack of gene flow after speciation; an assumption which may be frequently violated in plant evolution. This study evaluates the robustness of currently available species delimitation methods implemented in beast (BFD, BFD*, and dissect) in the closely-knit ox-eye daisy group around Leucanthemum ageratifolium Pau. Comprising five taxa being allopatrically distributed between northern Spain and southern Italy this study group shows signs of hybridization with the widespread and codistributed species Leucanthemum vulgare (Vaill.) Lam. to various extent. As expected, our empirical analyses based on both AFLP fingerprinting and sequence data demonstrate that the robustness of species delimitation results is considerably influenced by the intensity of hybridization among species and the number of hybrid individuals included. Therefore, we set up a methodological pipeline with a first step of identification and subsequent removal of individuals showing admixed genetic patterns caused by actual interbreeding using AFLP-fingerprint and morphometric data, followed by application of different Bayesian MSC species delimitation methods based on the remnant individuals using both AFLP-fingerprint and sequence data (four nuclear markers, five concatenated intergenic spacer regions of the plastid genome). The results argue for acknowledgement of Leucanthemum laciniatum, L. legraeanum, and L. ligusticum as independent species, show the close relationship of L. ageratifolium, L. monspeliense, and L. vulgare, and give rise to the description of three nothospecies new to science. © 2017 John Wiley & Sons Ltd.

  14. The chemical inducer, BTH (benzothiadiazole) and root colonization by mycorrhizal fungi (Glomus spp.) trigger resistance against white rot (Sclerotinia sclerotiorum) in sunflower.

    Science.gov (United States)

    Bán, Rita; Baglyas, Gellért; Virányi, Ferenc; Barna, Balázs; Posta, Katalin; Kiss, József; Körösi, Katalin

    2017-03-01

    White rot caused by Sclerotinia sclerotiorum (SS) is one of the most devastating plant diseases of sunflower. Controlling this pathogen by available tools hardly result in acceptable control. The aim of this study was to elucidate the effects of plant resistance inducers, BTH (benzothiadiazole in Bion 50 WG) and arbuscular mycorrhizal fungi (AMF) on disease development of white rot in three sunflower genotypes. Defence responses were characterized by measuring the disease severity and identifying cellular/histological reactions (e.g. autofluorescence) of host plants upon infection. Depending on the host genotype, a single application of inducers reduced disease symptoms. Histological examination of host responses revealed that BTH and/or AMF pre-treatments significantly impeded the development of pathogenic hyphae in Iregi szürke csíkos and P63LE13 sunflower plants and it was associated with intensive autofluorescence of cells. Both localized and systemic induction of resistance was observed. Importantly, the frequency of mycorrhization of hybrid P63LE13 and PR64H41 was significantly increased upon BTH treatment, so it had a positive effect on the formation of plant-mycorrhiza interactions in sunflower. To our knowledge, this is the first report on the additive effect of BTH on mycorrhization and the positive effect of these inducers against SS in sunflower.

  15. Sunflower centromeres consist of a centromere-specific LINE and a chromosome-specific tandem repeat

    Directory of Open Access Journals (Sweden)

    Kiyotaka eNagaki

    2015-10-01

    Full Text Available The kinetochore is a protein complex including kinetochore-specific proteins that plays a role in chromatid segregation during mitosis and meiosis. The complex associates with centromeric DNA sequences that are usually species-specific. In plant species, tandem repeats including satellite DNA sequences and retrotransposons have been reported as centromeric DNA sequences. In this study on sunflowers, a cDNA-encoding centromere-specific histone H3 (CENH3 was isolated from a cDNA pool from a seedling, and an antibody was raised against a peptide synthesized from the deduced cDNA. The antibody specifically recognized the sunflower CENH3 (HaCENH3 and showed centromeric signals by immunostaining and immunohistochemical staining analysis. The antibody was also applied in chromatin immunoprecipitation (ChIP-Seq to isolate centromeric DNA sequences and two different types of repetitive DNA sequences were identified. One was a long interspersed nuclear element (LINE-like sequence, which showed centromere-specific signals on almost all chromosomes in sunflowers. This is the first report of a centromeric LINE sequence, suggesting possible centromere targeting ability. Another type of identified repetitive DNA was a tandem repeat sequence with a 187-bp unit that was found only on a pair of chromosomes. The HaCENH3 content of the tandem repeats was estimated to be much higher than that of the LINE, which implies centromere evolution from LINE-based centromeres to more stable tandem-repeat-based centromeres. In addition, the epigenetic status of the sunflower centromeres was investigated by immunohistochemical staining and ChIP, and it was found that centromeres were heterochromatic.

  16. Detection of the parasitic plant, Orobanche cumana on sunflower ...

    African Journals Online (AJOL)

    Orobanche cumana broomrape is a parasitic plant described as an agricultural problem for sunflower production in many countries. In Tunisia, this pathogen was found parasitizing sunflower cultivars in some fields in the Béja region, for the first time during the 2009-2010 agricultural season. Clear O. cumana attachments ...

  17. Crystal morphology of sunflower wax in soybean oil organogel

    Science.gov (United States)

    While sunflower wax has been recognized as an excellent organogelator for edible oil, the detailed morphology of sunflower wax crystals formed in an edible oil organogel has not been fully understood. In this study, polarized light microscopy, phase contrast microscopy, scanning electron microscopy ...

  18. Sunflower seeds as eliciting agents of Compositae dermatitis

    DEFF Research Database (Denmark)

    Paulsen, Evy; El-Houri, Rime B; Andersen, Klaus Ejner

    2015-01-01

    : The prevalence of sensitivity to sunflower in Compositae-allergic individuals was 56%. A solvent wash of whole sunflower seeds yielded an extract containing SLs, the principal component tentatively being identified as argophyllin A or B, other SLs being present in minute amounts. CONCLUSIONS: The concentration...

  19. The sunflower affair; L'affaire tournesol

    Energy Technology Data Exchange (ETDEWEB)

    Boulanger, V.

    2003-11-01

    The sunflower oils is a weak percentage of the bio-fuels market, but is largely used in the agricultural engines. This oil can be produced without industrial process, which is a great interest for the farmers. The process and the financial situation of the sunflower oil are presented. (A.L.B.)

  20. 33 CFR 117.677 - Big Sunflower River.

    Science.gov (United States)

    2010-07-01

    ... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false Big Sunflower River. 117.677 Section 117.677 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY BRIDGES DRAWBRIDGE OPERATION REGULATIONS Specific Requirements Mississippi § 117.677 Big Sunflower River. The draw of...

  1. Potential allelopathic effects of sunflower ( Helianthus annuus L. ) on ...

    African Journals Online (AJOL)

    Potential allelopathic effects of sunflower (Helianthus annuus L.) cultivar Hysun 38 on Rhizobium, Azospirillum, and phosphate-solubilizing bacteria (PSB) were studied by applying oxidase, QTS tests and Gram staining. Microorganisms for the control group were isolated from soil sampled before sowing sunflower.

  2. Effect of intercropping sunflower with soybean at different interrow ...

    African Journals Online (AJOL)

    Sunflower (Helianthus annuus L.) and soybean (Glycine max) were relatively new crops of economic significance in Uganda before 1990s compared to traditional cash crops such as cotton, tea and coffee. By 2000 many smallholder farmers in the Mid-Northern Agro-ecological Zone of Uganda started planting sunflower ...

  3. 7 CFR 201.56-2 - Sunflower family, Asteraceae (Compositae).

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 3 2010-01-01 2010-01-01 false Sunflower family, Asteraceae (Compositae). 201.56-2...-2 Sunflower family, Asteraceae (Compositae). Kinds of seed: Artichoke, cardoon, chicory, dandelion... discolored. (Toxic materials in the substratum may cause short, blunt roots; see § 201.58(a)(9).) (C) Primary...

  4. SUNflower +6 : development and application of a footprint methodology for the SUNflower +6 countries.

    NARCIS (Netherlands)

    Morsink, P. Oppe, S. Reurings, M. & Wegman, F.C.M.

    2006-01-01

    Progress in traffic safety is the result of many efforts, starting with political decisions, the development of safety plans and safety actions and their implementation. This report explores ways of presenting information from the SUNflower+6 countries in such a way that it shows how the interaction

  5. Culture characteristics and histological changes in leaf tissues of cultivated and wild sunflowers infected with Alternaria helianthi

    OpenAIRE

    Madhavi K.J.; Sujatha M; Reddy Ram Raja D.; Rao Chander S.

    2005-01-01

    The cultural characteristics and histochemical variations following infection with Alternaria helianthi was studied In six wild Helianthus species of threeploidy levels (diploid, tetraploid and hexaploid) possessing different degrees of resistance to the pathogen and in cultivated sunflower (H. annuus cv. CO-4. susceptible check). Of these, the species II. occidentals and H. tuberosus were found to be highly resistant while H. hlrsutus was moderately resistant. Media supplemented with leaf ex...

  6. Registration of two confection sunflower germplasm Lines, HA-R10 and HA-R11, Resistant to sunflower rust

    Science.gov (United States)

    Two confection sunflower (Helianthus annuus L.) germplasm lines, HA-R10 (Reg. No.xxx, PI670043) and HA-R11 (Reg. No.xxx, PI670044) were developed by the USDA-ARS Sunflower and Plant Biology Research Unit in collaboration with the North Dakota Agricultural Experiment Station and released December, 20...

  7. Sensory properties during storage of crisps and French fries prepared with sunflower oil and high oleic sunflower oil

    NARCIS (Netherlands)

    Gemert, L.J. van

    1996-01-01

    A selected and trained descriptive sensory panel has assessed samples of crisps and French fries prepared on an industrial scale with either sunflower oil (SO) or high oleic sunflower oil (HOSO). Furthermore, crisps have been fried in these oils with or without dimethyl polysiloxane (DMPS).

  8. [Nutritive-physiological study of sunflower seed protein isolate and spun sunflower seed protein-casein fibers].

    Science.gov (United States)

    Proll, J; Uhlig, J; Schmandke, H; Noack, R

    1977-01-01

    Compared with defatted sunflower seeds, in sunflower seed globulin isolates the content of lysine and sulphur containing amino acids is decreased, the content of phenylalanine is increased. The content of the whole essential amino acids of sunflower seed globulin isolate in relation to casein is decreased. The value of the enzymatic invitro available amino acids of sunflower seed globulin is comparable with casein. The digestibility is good, the biological value is in relation to defatted sunflower seed lower. Apart from the lower content of sulphur-containing amino acids the amino acid composition of spun sunflower seed globulin/casein (I:I) fibers corresponds with the calculated value; in relation to sunflower seed globulin isolate the content of lysine and the whole essential amino acids of the spun protein fibers is increased. The enzymatic in-vitro-hydrolysis results altogether in a comparable availability of the amino acids between spun protein fibers and sunflower seed globulin isolates. The digestibility and the biological value of spun protein fibers corresponds with that of casein.

  9. Pentatomidae bugs associated with sunflower crops in the northwest of Rio Grande do Sul state and the action of Euschistus heros (Fabricius, 1794 (Hemiptera: Pentatomidae on sunfl ower seeds

    Directory of Open Access Journals (Sweden)

    Régis Sivori Silva dos Santos

    2007-12-01

    Full Text Available The goals of this study were to identify the species of bugs attacking sunflowers in the northwest of Rio Grande do Sul state and to estimate the damage caused during the R6 and R8 stages. The bugs present in ten sunflower crops were collected, and their feeding sites were determined. The species Euschistus heros (Fabricius, 1794 was used to determine the damage by individualizing the capitula using mesh cages in the R6 and R8 stages. Each caged capitulum was infested with one, two, or four bugs. Besides E. heros (47.67%, Dichelops furcatus (Fabricius, 1775 (44.18%, Piezodorus guildinii (Westwood, 1837 (4.65% and Edessa meditabunda (Fabricius, 1794 (3.48% were found. There were no significant differences among the treatments regarding the yield components (weight of 1000 sunflower seeds, germination power, oil and protein content. The tetrazolio test indicated that the bugs fed on the sunflower seeds.

  10. Impact of major gene resistance management for sunflower on fitness of Plasmopara halstedii (downy mildew populations

    Directory of Open Access Journals (Sweden)

    Tourvieille de Labrouhe Denis

    2010-01-01

    Full Text Available Changes in virulence of Plasmopara halstedii populations under different major gene (Pl management strategies were studied over 5 years continuous cropping of one sunflower hybrid under netting cages. Strategies were monoculture of forms of the hybrid with 1 gene or with combinations of 2 genes, alternation of different genes, and mixtures of several different forms of the hybrid. Monoculture with single resistance genes led to loss of efficient resistance after 3 years, with high levels of disease and increased variability of the pathogen, whatever the Pl gene used. Combinations of genes, alternation and mixtures gave longer term control of downy mildew. In particular, combinations of resistance genes coming from both female and male parents of the hybrid (such that even impurities had a resistance gene gave the best control and least variation in pathogen virulence. Results are discussed with the object of durable control of downy mildew by all methods available.

  11. 15th International Sunflower Conference Horizontal resistances in sunflower: a review of a workshop at the 15th International Sunflower Conference

    Directory of Open Access Journals (Sweden)

    Castano Fernando

    2001-05-01

    Full Text Available A workshop on horizontal resistance at the 15th International Sunflower Conference, held in Toulouse, France, from June 12 to 16, 2000, covered topics including the evaluation, stability and inheritance of resistance of sunflower to Sclerotinia sclerotiorum, Diaporthe helianthi, Alternaria helianthi and Verticillium dahliae. It was notable that research continues into evaluation methodology at the same time as quantitative genetics, use of molecular markers, search for QTL and resistance improvement by genetic engineering.

  12. Multiple-geographic-scale genetic structure of two mangrove tree species: the roles of mating system, hybridization, limited dispersal and extrinsic factors.

    Directory of Open Access Journals (Sweden)

    Gustavo M Mori

    Full Text Available Mangrove plants comprise a unique group of organisms that grow within the intertidal zones of tropical and subtropical regions and whose distributions are influenced by both biotic and abiotic factors. To understand how these extrinsic and intrinsic processes influence a more fundamental level of the biological hierarchy of mangroves, we studied the genetic diversity of two Neotropical mangrove trees, Avicenniagerminans and A. schaueriana, using microsatellites markers. As reported for other sea-dispersed species, there was a strong differentiation between A. germinans and A. schaueriana populations sampled north and south of the northeastern extremity of South America, likely due to the influence of marine superficial currents. Moreover, we observed fine-scale genetic structures even when no obvious physical barriers were present, indicating pollen and propagule dispersal limitation, which could be explained by isolation-by-distance coupled with mating system differences. We report the first evidence of ongoing hybridization between Avicennia species and that these hybrids are fertile, although this interspecific crossing has not contributed to an increase in the genetic diversity the populations where A. germinans and A. schaueriana hybridize. These findings highlight the complex interplay between intrinsic and extrinsic factors that shape the distribution of the genetic diversity in these sea-dispersed colonizer species.

  13. Multiple-geographic-scale genetic structure of two mangrove tree species: the roles of mating system, hybridization, limited dispersal and extrinsic factors.

    Science.gov (United States)

    Mori, Gustavo M; Zucchi, Maria I; Souza, Anete P

    2015-01-01

    Mangrove plants comprise a unique group of organisms that grow within the intertidal zones of tropical and subtropical regions and whose distributions are influenced by both biotic and abiotic factors. To understand how these extrinsic and intrinsic processes influence a more fundamental level of the biological hierarchy of mangroves, we studied the genetic diversity of two Neotropical mangrove trees, Avicenniagerminans and A. schaueriana, using microsatellites markers. As reported for other sea-dispersed species, there was a strong differentiation between A. germinans and A. schaueriana populations sampled north and south of the northeastern extremity of South America, likely due to the influence of marine superficial currents. Moreover, we observed fine-scale genetic structures even when no obvious physical barriers were present, indicating pollen and propagule dispersal limitation, which could be explained by isolation-by-distance coupled with mating system differences. We report the first evidence of ongoing hybridization between Avicennia species and that these hybrids are fertile, although this interspecific crossing has not contributed to an increase in the genetic diversity the populations where A. germinans and A. schaueriana hybridize. These findings highlight the complex interplay between intrinsic and extrinsic factors that shape the distribution of the genetic diversity in these sea-dispersed colonizer species.

  14. Performance of sunflower cultivars at different seeding periods in central Brazil

    Directory of Open Access Journals (Sweden)

    Marcos Birck

    Full Text Available ABSTRACT Sunflower (Helianthus annuus L. is a very important crop for Brazil, and especially for Chapada do Parecis which is the largest domestic producer, because of its climate and soil conditions are adequate to the development of the specie. The performance of cultivars and sunflower seed sowing periods were evaluated in Central Brazil. Experimental design comprised an 8 x 5 factorial randomized complete block, with eight sunflower cultivars (Aguará 06, Aguará 04, MG 305, CF 101, SYN 3950HO, SYN 045, GNZ NEON and HELIO 251 and five decennial seeding periods, with three replicates. Analysis of variance and Scott-Knott´s test (p<0.05 were applied. Cultivars GNZ NEON and SYN 045 provide the highest production rates in achenes, with higher value in favor of GNZ NEON. SYN 3950HO (this with higher value, CF101, MG 305, SYN 045 and Aguará 04 gets the highest oil rates in the achenes, with SYN 045, GNZ NEON, Aguará 04, CF101 and SYN 3950HO with the highest oil production. The first seed sowing period is the most productive and the first and fifth periods have the best results for oil productivity. Cultivar GNZ NEON and the first period exceede the others with regard to vegetative and reproductive variables.

  15. Radiation efficiency and nitrogen fertilizer impacts on sunflower crop in contrasting environments of Punjab, Pakistan.

    Science.gov (United States)

    Nasim, Wajid; Ahmad, Ashfaq; Amin, Asad; Tariq, Muhammad; Awais, Muhammad; Saqib, Muhammad; Jabran, Khawar; Shah, Ghulam Mustafa; Sultana, Syeda Refat; Hammad, Hafiz Mohkum; Rehmani, Muhammad Ishaq Asif; Hashmi, Muhammad Zaffar; Rahman, Muhammad Habib Ur; Turan, Veysel; Fahad, Shah; Suad, Shah; Khan, Aziz; Ali, Shahzad

    2018-01-01

    Sunflower (Helianthus annuus L.) is the leading non-conventional oilseed crop in Pakistan. Nitrogen fertilizer can affect plant growth and productivity by changing canopy size which has an effect on the radiation use efficiency (RUE) of the crop. The response of sunflower hybrids in terms of phenology, fraction of intercepted radiation (F i), and RUE to nitrogenous rates (0, 60, 120, 180, and 240 kg ha-1) was studied in three field experiments conducted in three various environments: Multan (arid), Faisalabad (semi-arid), and Gujranwala (sub-humid) during spring seasons 2008 and 2009. The treatments were laid out according to a randomized complete block design with split plot arrangements, keeping the sunflower hybrids in main plots and nitrogen rates in sub-plots, and replicated three times. The results showed Hysun-38 took a maximum number of days to anthesis (101) as compared to Pioneer-64A93 (100) and Hysun-33 (99). The mean values of F i were 0.850, 0.903, and 0.978, and the estimated values of RUE for total aboveground dry matter were 2.14, 2.47, and 2.65 g MJ-1 at experimental locations of Multan, Faisalabad, and Gujranwala, respectively. The values of RUE for grain yield (RUEGY) were 0.78, 0.98, and 1.26 g MJ-1 at experimental locations of Multan, Faisalabad, and Gujranwala, respectively. The average RUEGY values over three locations were 2.61, 2.60, 2.43, and 2.36 g MJ-2 in N4 (180 kg ha-1), N5 (240 kg ha-1), N3 (120 kg ha-1), and N2 (60 kg ha-1) treatments, respectively. Increasing rates of N increased RUEGY over the standard treatment N3 (120 kg N ha-1); however, the averaged values over three locations were 1.22, 1.08, 0.99, and 0.92 g MJ-2 in N4, N5, N3, and N2 treatments, respectively. Therefore, optimum water and N doses are important for attaining higher RUE, which may enhance sunflower growth and yield.

  16. Rapid species identification of "Streptococcus milleri" strains by line blot hybridization: identification of a distinct 16S rRNA population closely related to Streptococcus constellatus.

    Science.gov (United States)

    Jacobs, J A; Schot, C S; Bunschoten, A E; Schouls, L M

    1996-01-01

    A collection of 399 "Streptococcus milleri" strains were identified to the species level by the use of a line blot assay. Their PCR-amplified partial 16S rRNA gene sequences were hybridized with species-specific 5'-biotinylated oligonucleotide probes homologous to the bp 213 to 231 regions of the 16S rRNA gene sequences of the type strains Streptococcus anginosus ATCC 33397, Streptococcus constellatus ATCC 27823, and Streptococcus intermedius ATCC 27335. The hybridization results were compared with the reference phenotypic identification method data (R. A. Whiley, H. Fraser, J. M. Hardie, and D. Beighton, J. Clin. Microbiol. 28:1497-1501, 1990). Most strains (357 of 399 [89.5%]) reacted unambiguously with only one probe. However, 42 of the 399 strains (10.5%) reacted with both the S. constellatus- and S. intermedius-specific probes; 41 of them were phenotypically identified as S. constellatus. These dually reactive strains hybridized with a 5'-biotinylated probe based on the bp 213 to 231 region of the 16S rRNA gene sequence of one of two species. Analysis of the 5' ends of the 16S rRNA gene sequences (487 bp) demonstrated that the dually reactive strains represent a distinct rRNA population sharing 98.1% sequence similarity with S. constellatus. Phenotypic consistency between the dually reactive strains and the S. constellatus strains was not demonstrated. Line blot hybridization proved to be a simple and inexpensive method to screen large numbers of strains for genetic relatedness, and it allowed the detection of a distinct 16S rRNA type within the "S. milleri" group. PMID:8784576

  17. The Accumulation of Deleterious Mutations as a Consequence of Domestication and Improvement in Sunflowers and Other Compositae Crops.

    Science.gov (United States)

    Renaut, Sebastien; Rieseberg, Loren H

    2015-09-01

    For populations to maintain optimal fitness, harmful mutations must be efficiently purged from the genome. Yet, under circumstances that diminish the effectiveness of natural selection, such as the process of plant and animal domestication, deleterious mutations are predicted to accumulate. Here, we compared the load of deleterious mutations in 21 accessions from natural populations and 19 domesticated accessions of the common sunflower using whole-transcriptome single nucleotide polymorphism data. Although we find that genetic diversity has been greatly reduced during domestication, the remaining mutations were disproportionally biased toward nonsynonymous substitutions. Bioinformatically predicted deleterious mutations affecting protein function were especially strongly over-represented. We also identify similar patterns in two other domesticated species of the sunflower family (globe artichoke and cardoon), indicating that this phenomenon is not due to idiosyncrasies of sunflower domestication or the sunflower genome. Finally, we provide unequivocal evidence that deleterious mutations accumulate in low recombining regions of the genome, due to the reduced efficacy of purifying selection. These results represent a conundrum for crop improvement efforts. Although the elimination of harmful mutations should be a long-term goal of plant and animal breeding programs, it will be difficult to weed them out because of limited recombination. © The Author 2015. Published by Oxford University Press on behalf of the Society for Molecular Biology and Evolution. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  18. Identification and characterization of contrasting sunflower genotypes to early leaf senescence process combining molecular and physiological studies (Helianthus annuus L.).

    Science.gov (United States)

    López Gialdi, A I; Moschen, S; Villán, C S; López Fernández, M P; Maldonado, S; Paniego, N; Heinz, R A; Fernandez, P

    2016-09-01

    Leaf senescence is a complex mechanism ruled by multiple genetic and environmental variables that affect crop yields. It is the last stage in leaf development, is characterized by an active decline in photosynthetic rate, nutrients recycling and cell death. The aim of this work was to identify contrasting sunflower inbred lines differing in leaf senescence and to deepen the study of this process in sunflower. Ten sunflower genotypes, previously selected by physiological analysis from 150 inbred genotypes, were evaluated under field conditions through physiological, cytological and molecular analysis. The physiological measurement allowed the identification of two contrasting senescence inbred lines, R453 and B481-6, with an increase in yield in the senescence delayed genotype. These findings were confirmed by cytological and molecular analysis using TUNEL, genomic DNA gel electrophoresis, flow sorting and gene expression analysis by qPCR. These results allowed the selection of the two most promising contrasting genotypes, which enables future studies and the identification of new biomarkers associated to early senescence in sunflower. In addition, they allowed the tuning of cytological techniques for a non-model species and its integration with molecular variables. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  19. Genomic in situ hybridization reveals both auto- and allopolyploid origins of different North and Central American hexaploid potato (Solanum sect. Petota) species.

    Science.gov (United States)

    Pendinen, Galina; Spooner, David M; Jiang, Jiming; Gavrilenko, Tatjana

    2012-06-01

    Wild potato ( Solanum L. sect. Petota Dumort.) species contain diploids (2n = 2x = 24) to hexaploids (2n = 6x = 72). J.G. Hawkes classified all hexaploid Mexican species in series Demissa Bukasov and, according to a classic five-genome hypothesis of M. Matsubayashi in 1991, all members of series Demissa are allopolyploids. We investigated the genome composition of members of Hawkes's series Demissa with genomic in situ hybridization (GISH), using labeled DNA of their putative progenitors having diploid AA, BB, or PP genome species or with DNA of tetraploid species having AABB or AAA(a)A(a) genomes. GISH analyses support S. hougasii Correll as an allopolyploid with one AA component genome and another BB component genome. Our results also indicate that the third genome of S. hougasii is more closely related to P or a P genome-related species. Solanum demissum Lindl., in contrast, has all three chromosome sets related to the basic A genome, similar to the GISH results of polyploid species of series Acaulia Juz. Our results support a more recent taxonomic division of the Mexican hexaploid species into two groups: the allopolyploid Iopetala group containing S. hougasii, and an autopolyploid Acaulia group containing S. demissum with South American species S. acaule Bitter and S. albicans (Ochoa) Ochoa.

  20. Study of Quality and Quantity of Yield and Land Equivalent Ratio of Sunflower in Intercropping Series with Bean

    Directory of Open Access Journals (Sweden)

    Javad Hamzei

    2017-03-01

    Full Text Available Introduction Intercropping is an old and widespread practice used in low input cropping systems in many areas of the world. In fact, intercropping is claimed to be one of the most significant cropping techniques in sustainable agriculture, and many researches and reviews attribute its utilization to the number of environmental benefits from promoting land biodiversity to diversifying agricultural outcome. Furthermore, it is thought to be a useful mean for minimizing the risks of agricultural production in many environments, including those typical of under-developed or marginal areas. Intercropping systems, especially those employing non legumes with legumes, have several major advantages such as higher total yield and better land use efficiency (Dhima et al., 2007, yield stability of the cropping system (Lithourgidis et al., 2007, better utilization of light, water, and nutrients (Javanmard et al., 2009, improved soil conservation and better control of pests and weeds. Intercrops including of legume are common in agriculture ecosystems, but now are rarely used in developed countries, except for certain intercropping systems used for animal feed. Intercrops can use the available environmental resources more efficiently and thus result in higher yields than mono crops. The reasons for the higher yield in such systems is that the intercropped species do not compete for exactly the same growth resource niche and thereby tend to use the available resources in a complementary way. In particular, non legumes seem to be more competitive for soil inorganic nitrogen (N than legumes due to faster and deeper root growth and higher demand in N. Consequently, the legumes usually increase their reliance on symbiotic N2 fixation. In the present study, it was aimed to assess the production of biomass, yield, grain quality and land equivalent ratio (LER in plant society of sunflower/bean. Materials and methods This experiment was carried out with aim of

  1. Incongruence between morphotypes and genetically delimited species in the coral genus Stylophora: phenotypic plasticity, morphological convergence, morphological stasis or interspecific hybridization?

    Science.gov (United States)

    Flot, Jean-François; Blanchot, Jean; Charpy, Loïc; Cruaud, Corinne; Licuanan, Wilfredo Y; Nakano, Yoshikatsu; Payri, Claude; Tillier, Simon

    2011-10-04

    Morphological data suggest that, unlike most other groups of marine organisms, scleractinian corals of the genus Stylophora are more diverse in the western Indian Ocean and in the Red Sea than in the central Indo-Pacific. However, the morphology of corals is often a poor predictor of their actual biodiversity: hence, we conducted a genetic survey of Stylophora corals collected in Madagascar, Okinawa, the Philippines and New Caledonia in an attempt to find out the true number of species in these various locations. A molecular phylogenetic analysis of the mitochondrial ORF and putative control region concurs with a haploweb analysis of nuclear ITS2 sequences in delimiting three species among our dataset: species A and B are found in Madagascar whereas species C occurs in Okinawa, the Philippines and New Caledonia. Comparison of ITS1 sequences from these three species with data available online suggests that species C is also found on the Great Barrier Reef, in Malaysia, in the South China Sea and in Taiwan, and that a distinct species D occurs in the Red Sea. Shallow-water morphs of species A correspond to the morphological description of Stylophora madagascarensis, species B presents the morphology of Stylophora mordax, whereas species C comprises various morphotypes including Stylophora pistillata and Stylophora mordax. Genetic analysis of the coral genus Stylophora reveals species boundaries that are not congruent with morphological traits. Of the four hypotheses that may explain such discrepancy (phenotypic plasticity, morphological stasis, morphological convergence, and interspecific hybridization), the first two appear likely to play a role but the fourth one is rejected since mitochondrial and nuclear markers yield congruent species delimitations. The position of the root in our molecular phylogenies suggests that the center of origin of Stylophora is located in the western Indian Ocean, which probably explains why this genus presents a higher biodiversity in

  2. Evaluating species limits and hybridization in the Carex complanata complex using morphology, amplified fragment length polymorphisms, and restriction fragment analysisThis paper is one of a selection of papers published in the Special Issue on Systematics Research

    National Research Council Canada - National Science Library

    Waterway, Marcia J; Smith, Tyler W

    2008-01-01

    We used a combination of morphology, amplified fragment length polymorphisms (AFLP), and restriction-site data from 252 individuals from 51 populations to investigate species limits and hybridization in the Carex complanata complex...

  3. Cape heaths in European gardens: the early history of South African Erica species in cultivation, their deliberate hybridization and the orthographic bedlam

    Directory of Open Access Journals (Sweden)

    E. C. Nelson

    2004-12-01

    Full Text Available This paper discusses the horticultural history of southern African Erica spp. in Europe, and especially in Britain, during the late eighteenth and the early decades of the nineteenth century . We note evidence for the deliberate hybridization of the so-called Cape heaths by European horticulturists, in particular by the English nursery man William Rollisson and by the Very Rev. William Herbert. We discuss some of the nomenclatural consequences of the naming by miscellaneous botanists and nurserymen of the hundreds of new Erica species and hybrids, emphasizing the proliferation of eponyms. An appendix tabulates eponyms and their numerous orthographic variants published before 1835 within Erica, and provides the correct orthography for these epithets.

  4. Sunflower Beauty Contest : tsvetõ zimoi / Marina Poltavtseva

    Index Scriptorium Estoniae

    Poltavtseva, Marina

    2001-01-01

    Lillekleitide võistlusest Sunflower Beauty Contest Tallinna klubis Decolte. Konkursi idee on florist Tatjana Tridvornovalt. Esimese koha sai Viimsi lilleäri lilleseadjate Meri-Liis Kõivu ja Triinu Põlderi lillekleit "Talvepruut"

  5. Infrared Imaging of Sunflower and Maize Root Anatomy

    Energy Technology Data Exchange (ETDEWEB)

    Dokken,K.; Davis, L.

    2007-01-01

    Synchrotron radiation infrared microspectroscopy (SR-IMS) permits the direct analysis of plant cell-wall architecture at the cellular level in situ, combining spatially localized information and chemical information from IR absorbances to produce a chemical map that can be linked to a particular morphology or functional group. This study demonstrated the use of SR-IMS to probe biopolymers, such as cellulose, lignin, and proteins, in the root tissue of hydroponically grown sunflower and maize plants. Principal components analysis (PCA) was employed to reveal the major spectral variance between maize and sunflower plant tissues. The use of PCA showed distinct separation of maize and sunflower samples using the IR spectra of the epidermis and xylem. The infrared band at 1635 cm-1, representing hydrocinnamic acid in (H type) lignin, provided a conclusive means of distinguishing between maize and sunflower plant tissues.

  6. Final Critical Habitat for the Pecos Sunflower (Helianthus paradoxus)

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — To provide the user with a general idea of areas where final critical habitat for Pecos Sunflower (Helianthus paradoxus) occur. The geographic extent includes...

  7. Detection of the parasitic plant, Orobanche cumana on sunflower ...

    African Journals Online (AJOL)

    enoh

    2012-03-01

    Mar 1, 2012 ... Orobanche cumana broomrape is a parasitic plant described as an agricultural problem for sunflower production in many ... hosts first occur at the underground level by the parasite ..... Parasitic Flowering Plants: Ecology and.

  8. Influence of aging process on biochemical changes in sunflower seed

    OpenAIRE

    Balešević-Tubić Svetlana; Malenčić Đ.; Tatić Mladen; Miladinović Jegor

    2005-01-01

    This investigation was conducted in order to determine the degree of biochemical changes during accelerated and natural aging of sunflower seed. Five sunflower lines developed in Novi Sad, submitted to accelerated aging for three and five days, and natural aging of six and twelve months under conventional storage and controlled conditions, were used in these trials. Malondialdehyde, superoxide dismutase contents and peroxidase activities were studied. Lipid peroxidation and superoxide dismuta...

  9. Oryzanol as natural antioxidant for improving sunflower oil stability.

    Science.gov (United States)

    Sunil, L; Srinivas, P; Prasanth Kumar, P K; Gopala Krishna, A G

    2015-06-01

    Sunflower oil is being made shelf stable by the incorporation of synthetic antioxidants such as tertiary butyl hydroquinone (TBHQ), while natural antioxidants like oryzanol and tocopherols can also be used. The aim of the current investigation was to evaluate the antioxidant effect of natural oryzanol (Oz) concentrate (15.5 % oryzanol) and purified Oz (80 % oryzanol) on oxidative and thermal stability of sunflower oil. Sunflower oil was incorporated with Oz concentrate to provide 0, 0.12, 0.25, 0.50, 0.84, 1.0, 1.60, 2.0, 2.5 and 3.20 % oryzanol in the oil, stored for 5 weeks at 37 °C and oxidative stability was evaluated. It was found that the oryzanol concentrate showed good antioxidant effect with increase in concentration of oryzanol. In another set of experiments, sunflower oil containing purified Oz at 1 % level individually and in combination with 0.1 % α- tocopherol (α-T) was heated at 120 °C for 24 h to evaluate thermal stability. Sunflower oil containing 1 % Oz (80 % purity) showed 98.40 % and sunflower oil containing 1 % Oz and 0.1 % α-T showed 108.75 % antioxidant effect compared to TBHQ taken as 100 %. The study indicated that sunflower oil containing 1 % Oz (80 % purity) and 0.1 % α-T combination provides a synergistic effect in inhibiting primary and secondary products and showed highest thermal stability. SFO containing 1 % Oz added as concentrate also showed good antioxidant effect during storage. Hence, instead of using synthetic antioxidants like TBHQ, we can add natural oryzanol (purified or as concentrate) to sunflower oil to increase its oxidative and thermal stability.

  10. A crop model-based approach for sunflower yields

    OpenAIRE

    Leite, João Guilherme Dal Belo; Silva, João Vasco; Justino, Flávio Barbosa; Ittersum, Martin K. van

    2014-01-01

    Pushed by the Brazilian biodiesel policy, sunflower (Helianthus annuus L.) production is becoming increasingly regarded as an option to boost farmers' income, particularly under semi-arid conditions. Biodiesel related opportunities increase the demand for decision-making information at different levels, which could be met by simulation models. This study aimed to evaluate the performance of the crop model OILCROP-SUN to simulate sunflower development and growth under Brazilian conditions and ...

  11. Nutritional and energy values of sunflower cake for broilers

    Directory of Open Access Journals (Sweden)

    Eveline Berwanger

    2014-12-01

    Full Text Available The study aimed to determine the nutritional and energy values of sunflower cake for broilers through two experiments. The first study evaluated the energy values by the method of total excreta collection, using 100 broiler chicks 21–31 days old, divided into five treatments of 0%, 10%, 20%, 30% and 40% inclusion sunflower cake will reference a diet. The second experiment evaluated the influence of the period and the quantity supplied of sunflower cake on digestibility of amino acids by a forcedfeeding technique. Eighteen cockerels were used, divided into three treatments, which consisted of supplying 15 g of sunflower cake, 30 g of sunflower cake (15 g at intervals of 12 hours and 30 g of sunflower cake (15 g at intervals of 24 hours, and an additional six roosters were fasted for correction of metabolic and endogenous losses. The samples were sent for amino acid analysis by HPLC in the Evonik Laboratory (Germany, and chemical and energy analysis to Unioeste Laboratory. The values of apparent metabolizable energy (AME, metabolization coefficient (AMC, apparent metabolizable energy corrected for nitrogen balance (AMEn, metabolization coefficient corrected for nitrogen balance (AMCn for sunflower cake were 2211.68 kcal.kg-1, 2150.54 kcal.kg-1, 45.47% and 44.73%, respectively. The amount of food provided in the feeding method changed the assessment of true digestibility of amino acids (TDCA, and when only 15 g was used, the values of true digestibility coefficients were underestimated. The lysine, histidine and threonine amino acids were at lower TDCA, and arginine and methionine showed the highest TDCA for sunflower cake.

  12. Effect of heavy metals on plants. II. Net photosynthesis and transpiration of whole corn and sunflower plants treated with Pb, Cd, Ni, and Tl

    Energy Technology Data Exchange (ETDEWEB)

    Carlson, R.W.; Bazzaz, F.A.; Rolfe, G.L.

    1975-08-01

    Corn and sunflower plants were grown in hydroponic culture and treated with various levels of Pb, Cd, Ni, and Tl salts. Net photosynthesis, transpiration and toxic metal ion concentration of leaf material and total plant biomass was measured. Tl was found to be the most toxic to new photosynthesis and growth of both species followed in order by Cd, Ni, and Pb. (auth)

  13. Antioxidant Mechanism is Involved in the Gastroprotective Effects of Ozonized Sunflower Oil in Ethanol-Induced Ulcers in Rats

    OpenAIRE

    Zullyt B. Zamora Rodríguez; Ricardo González Álvarez; Dailén Guanche; Nelson Merino; Frank Hernández Rosales; Silvia Menéndez Cepero; Yaima Alonso González; Siegfried Schulz

    2007-01-01

    This research was performed in order to determine the potential protective effects of ozonized sunflower oil (OSO) in the injury of rat gastric mucosa induced by absolute ethanol and as well as to elucidate the role of reactive oxygen species (ROS), lipid peroxidation, and some important constituents of antioxidant defense such as superoxide dismutase (SOD), glutathione peroxidase (GSH-Px), and catalase (CAT) in these effects. OSO was administered to rats intragastrically by a cannula and it ...

  14. Genetic mapping of rust resistance genes in confection sunflower line HA-R6 and oilseed line RHA 397.

    Science.gov (United States)

    Gong, L; Gulya, T J; Markell, S G; Hulke, B S; Qi, L L

    2013-08-01

    tested so far. Our newly developed molecular markers will facilitate breeding efforts to pyramid the R 13 genes with other rust R-genes and accelerate the development of rust-resistant sunflower hybrids in both confection and oilseed sunflowers.

  15. Transferring of Sclerotinia resistance from wild into cultivated sunflower: Combining of conventional and laboratory techniques

    Directory of Open Access Journals (Sweden)

    Vasić Dragana M.

    2002-01-01

    Full Text Available Five populations of each H. molis, H. maximiliani, H. rigidus and H. tuberosus were screened for resistance to stem form of Sclerotinia. On the basis of the results obtained by screening, nine crosses of resistant populations with either other wild species populations or with cultivated sunflower were made. As in some crosses a small quantity of seed was produced and the seeds germinated poorly, modified tissue culture methods were used to enhance germination and produce clones of interesting plants. These methods were found to be efficient both for seed germination and plant production and multiplication.

  16. Phytotoxic effects of nickel on yield and concentration of macro- and micro-nutrients in sunflower (Helianthus annuus L.) achenes.

    Science.gov (United States)

    Ahmad, Muhammad Sajid Aqeel; Ashraf, Muhammad; Hussain, Mumtaz

    2011-01-30

    The phytotoxic effects of varying levels of nickel (0, 10, 20, 30, and 40 mg L(-1)) on growth, yield and accumulation of macro- and micro-nutrients in leaves and achenes of sunflower (Helianthus annuus L.) were appraised in this study. A marked reduction in root and shoot fresh biomass was recorded at higher Ni levels. Nickel stress also caused a substantial decrease in all macro- and micro-nutrients in leaves and achenes. The lower level of Ni (10 mg L(-1)) had a non-significant effect on various yield attributes, but higher Ni levels considerably decreased these parameters. Higher Ni levels decreased the concentrations of Ca, Mn and Fe in achenes. In contrast, achene N, K, Zn, Mn and Cu decreased consistently with increasing level of Ni, even at lower level (10 mg L(-1)). Sunflower hybrid Hysun-33 had better yield and higher most of the nutrients in achenes as compared with SF-187. The maximum reduction in all parameters was observed at the maximum level of nickel (40 mg L(-1)) where almost all parameters were reduced more than 50% of those of control plants. In conclusion, the pattern of uptake and accumulation of different nutrients in sunflower plants were nutrient- and cultivar-specific under Ni-stress. Copyright © 2010 Elsevier B.V. All rights reserved.

  17. Determining Critical Soil pH for Sunflower Production

    Directory of Open Access Journals (Sweden)

    Apurba Sutradhar

    2014-01-01

    Full Text Available Soil acidity has become a major yield-limiting factor in cropping systems of the Southern Great Plains, in which winter wheat (Triticum aestivum L. is the predominant crop. Sunflower (Helianthus annuus L. is a strong rotational crop with winter wheat due to its draught and heat tolerance. However, the effects of low soil pH on sunflower productivity have not been explored. The objective of this study was to determine the critical soil pH and aluminum concentration (AlKCl for sunflower. Sunflower was grown in a randomized complete block design with three replications of a pH gradient ranging from 4.0 to 7.0 at three locations with varying soil types. Soil pH was altered using aluminum sulfate (Al2(SO43 and hydrated lime (Ca(OH2. Plant height, vigor, and survivability were all negatively affected by soil acidity. Sunflower yield was reduced by 10% at or below soil pH 4.7 to 5.3 dependent upon location and soil type. Levels of AlKCl above 6.35 mg kg−1 reduced seed yield by 10% or greater. We concluded that sunflower may serve as a better rotational crop with winter wheat under acidic conditions when compared to other adaptable crops.

  18. Phytoremediation of Lead and Cadmium Contaminated Soils using Sunflower Plant

    Directory of Open Access Journals (Sweden)

    Nasser Sewalem

    2014-03-01

    Full Text Available Phytremediation has emerged as a practical approach to clean up metal-polluted soils. In this study the role of sunflower (Helianthus annuus L. plants as a potential phytoremediator to soils contaminated with cadmium (Cd and lead (Pb was investigated. Our results showed that the effect of Cd was stronger on the growth of the roots, while the effect of Pb was stronger on the shoots of sunflower seedlings. At the physiological level, Cd treatment was found to induce low levels of lipid peroxidation and membrane leakage with less affected photosynthesis in the leaves of the treated sunflower seedlings compared to the effects of Pb. The results presented here showed that a high amount of the total absorbed Cd (88.84% was accumulated in roots, while a high amount of the total absorbed Pb (71.39 was tranlocated to shoots of sunflower seedlings. Similar trends of Cd and Pb allocation between roots and shoots at the yield stage were recorded. We suggest here that sunflower plants may remediate Cd contaminated soils through phytostabilization, while may remediate Pb contaminated soils through phytoextraction. Finaly, the trace amounts of Cd and Pb that were accumulated in seeds recommends sunflower plants to be used safely and economically for cleaning up soils contaminated with Cd and/or Pb.

  19. Chemometric approach to develop frying stable sunflower oil blends stabilized with oleoresin rosemary and ascorbyl palmitate.

    Science.gov (United States)

    Upadhyay, Rohit; Sehwag, Sneha; Niwas Mishra, Hari

    2017-03-01

    The frying performance of sunflower oil blends (SOBs) stabilized with oleoresin rosemary (Rosmarinus officinalis L.) (ROSM) (200-1500mg/kg) and ascorbyl palmitate (AP) (100-300mg/kg) were tested for 18hopen pan-frying. Sunflower oil with TBHQ (SOTBHQ) (200mg/kg) and without additives (SOcontrol) served as positive and negative controls, respectively. The frying stability was monitored over time by estimating the levels of conjugated dienes, total polar compounds, polymeric compounds viz., triglyceride polymers, dimers, oxidized triglyceride monomers, diglycerides and free fatty acids, and induction period based on Rancimat. Chemometric tools were used to classify the oil samples based on frying stability. Thermo-oxidative changes were reduced significantly for blends stabilized with ROSM and AP (p<0.05). Principal component analysis (PCA) and hierarchical cluster analysis (HCA) distinguished SOBs from positive controls. A formulation consisting of 1309.62 and 129.29mg/kg of ROSM and AP, respectively, was optimized using a hybrid PCA-RSM approach. Copyright © 2016 Elsevier Ltd. All rights reserved.

  20. Estimation of mating system parameters in an evolving gynodioecous population of cultivated sunflower (Helianthus annuus L.).

    Science.gov (United States)

    Roumet, M; Ostrowski, M-F; David, J; Tollon, C; Muller, M-H

    2012-04-01

    Cultivated plants have been molded by human-induced selection, including manipulations of the mating system in the twentieth century. How these manipulations have affected realized parameters of the mating system in freely evolving cultivated populations is of interest for optimizing the management of breeding populations, predicting the fate of escaped populations and providing material for experimental evolution studies. To produce modern varieties of sunflower (Helianthus annuus L.), self-incompatibility has been broken, recurrent generations of selfing have been performed and male sterility has been introduced. Populations deriving from hybrid-F1 varieties are gynodioecious because of the segregation of a nuclear restorer of male fertility. Using both phenotypic and genotypic data at 11 microsatellite loci, we analyzed the consanguinity status of plants of the first three generations of such a population and estimated parameters related to the mating system. We showed that the resource reallocation to seed in male-sterile individuals was not significant, that inbreeding depression on seed production averaged 15-20% and that cultivated sunflower had acquired a mixed-mating system, with ∼50% of selfing among the hermaphrodites. According to theoretical models, the female advantage and the inbreeding depression at the seed production stage were too low to allow the persistence of male sterility. We discuss our methods of parameter estimation and the potential of such study system in evolutionary biology.

  1. RESPONSE OF TWO SUNFLOWER (HELIANTHUS ANNUUS L. GENOTYPES TO VA-MYCORRHIZAL INOCULATION AND PHOSPHORUS LEVELS

    Directory of Open Access Journals (Sweden)

    C.P. CHANDRASHEKARA, V.C. PATIL

    1995-01-01

    Full Text Available The performance of two sunflower genotypes (Morden and MSFH-8 with and without VA-mycorrhizal fungi at three P levels (38, 56 and 75 kg P2O5 ha-1 in vertisol of Dharwad was studied to determine the effect of mycorrhizal inoculation on plant growth, yield and P uptake. The results showed that the VAM inoculation increased sunflower yield (14%, total biomass (16%, oil content (3.1% and P uptake (30.5% over uninoculated control. The percent root colonization and chlamydo-spore count decreased with increasing P levels. The total biomass production, seed yield and P uptake of mycorrhizal plants at 38 kg P2O5 ha-1 more than the non-mycorrhizal plants at 75 kg P2O5 ha-1. The biomass and seed yield of mycorrhizal plants at same P level were more than the non-mycorrhizal plants. Mycorrhizal plants of Morden at 38 kg P2O5 ha-1 and MSFH-8 at 56 kg P2O5 ha-1 produced higher seed yield, oil content and total biomass than non-mycorrhizal plants supplied with 75 kg P2O5 ha-1. The results indicated that, VA-mycorrhizal inoculation helps in saving 25 and 50 percent of recommended dose of phosphatic fertilizer (75 kg P2O5 ha-1 in MSFH-8 (single cross hybrid and Morden (open pollinated variety, respectively.

  2. Serpocaulon × manizalense: a new hybrid between simple- and pinnate-leaved species of Serpocaulon (Polypodiaceae) from Colombia

    NARCIS (Netherlands)

    Sanín, D.; Torrez, V.

    2014-01-01

    During a revision of Serpocaulon from Colombia, a new hybrid was found between S. adnatum and S. levigatum near to Manizales city, which is described and illustrated herein. Qualitative and quantitative spore and macro-morphological characters were evaluated using principal component analyses to

  3. Genetic analysis of floral symmetry in Van Gogh's sunflowers reveals independent recruitment of CYCLOIDEA genes in the Asteraceae.

    Directory of Open Access Journals (Sweden)

    Mark A Chapman

    Full Text Available The genetic basis of floral symmetry is a topic of great interest because of its effect on pollinator behavior and, consequently, plant diversification. The Asteraceae, which is the largest family of flowering plants, is an ideal system in which to study this trait, as many species within the family exhibit a compound inflorescence containing both bilaterally symmetric (i.e., zygomorphic and radially symmetric (i.e., actinomorphic florets. In sunflower and related species, the inflorescence is composed of a single whorl of ray florets surrounding multiple whorls of disc florets. We show that in double-flowered (dbl sunflower mutants (in which disc florets develop bilateral symmetry, such as those captured by Vincent van Gogh in his famous nineteenth-century sunflower paintings, an insertion into the promoter region of a CYCLOIDEA (CYC-like gene (HaCYC2c that is normally expressed specifically in WT rays is instead expressed throughout the inflorescence, presumably resulting in the observed loss of actinomorphy. This same gene is mutated in two independent tubular-rayed (tub mutants, though these mutations involve apparently recent transposon insertions, resulting in little or no expression and radialization of the normally zygomorphic ray florets. Interestingly, a phylogenetic analysis of CYC-like genes from across the family suggests that different paralogs of this fascinating gene family have been independently recruited to specify zygomorphy in different species within the Asteraceae.

  4. Species-specific differences in tissue-specific expression of alcohol dehydrogenase are under the control of complex cis-acting loci: Evidence from Drosophila hybrids

    Energy Technology Data Exchange (ETDEWEB)

    Ranganayakulu, G.; Reddy, A.R. (University of Hyderbad (India)); Kirkpatrick, R.B.; Martin, P.F. (Drexel University, Philadelphia, PA (United States))

    1991-12-01

    Differences in the expression of alcohol dehydrogenase in the hindgut and testis of adult Drosophila virilis, D. texana, D. novamexicana and D. borealis flies were observed. These heritable differences do not arise due to chromosomal rearrangements, since the polytene chromosome banding patterns did not reveal any such gross chromosomal rearrangements near the Adh locus in any of the tested species. Analysis of the interspecific hybrids revealed that these differences are controlled by complex cis-acting genetic loci. Further, the cis-acting locus controlling the expression of ADH in testis was found to be separable by crossing-over.

  5. 15th International Sunflower Conference Synthesis of new derivatives from vegetable sunflower oil methyl esters via epoxydation and oxirane opening

    OpenAIRE

    Pages Xavier; Alfos Carine

    2001-01-01

    Recently, epoxides have received increased attention because they are of interest both as end-products and as chemical intermediates; epoxidized oils, mainly High Oleic Sunflower Oil, and their ester derivatives have thus found important applications as plasticizers and additives for polyvinyl chloride (PVC). Epoxidized esters have been produced classically from High Oleic Sunflower Methyl Esters (HOSME) using H2O2 and formic acid. The epoxidation reaches 90% on pilot scale (5kg). Epoxidized ...

  6. Phomopsis Stem Canker: A Reemerging Threat to Sunflower (Helianthus annuus) in the United States.

    Science.gov (United States)

    Mathew, Febina M; Alananbeh, Kholoud M; Jordahl, James G; Meyer, Scott M; Castlebury, Lisa A; Gulya, Thomas J; Markell, Samuel G

    2015-07-01

    Phomopsis stem canker causes yield reductions on sunflower (Helianthus annuus L.) on several continents, including Australia, Europe, and North America. In the United States, Phomopsis stem canker incidence has increased 16-fold in the Northern Great Plains between 2001 and 2012. Although Diaporthe helianthi was assumed to be the sole causal agent in the United States, a newly described species, D. gulyae, was found to be the primary cause of Phomopsis stem canker in Australia. To determine the identity of Diaporthe spp. causing Phomopsis stem canker in the Northern Great Plains, 275 infected stems were collected between 2010 and 2012. Phylogenetic analyses of sequences of the ribosomal DNA internal transcribed spacer region, elongation factor subunit 1-α, and actin gene regions of representative isolates, in comparison with those of type specimens, confirmed two species (D. helianthi and D. gulyae) in the United States. Differences in aggressiveness between the two species were determined using the stem-wound method in the greenhouse; overall, D. helianthi and D. gulyae did not vary significantly (P≤0.05) in their aggressiveness at 10 and 14 days after inoculation. These findings indicate that both Diaporthe spp. have emerged as sunflower pathogens in the United States, and have implications on the management of this disease.

  7. History of the race structure of Orobanche cumana and the breeding of sunflower for resistance to this parasitic weed: A review

    Energy Technology Data Exchange (ETDEWEB)

    Molinero-Ruiz, L.; Delavault, P.; Pérez-Vich, B.; Pacureanu-Joita, M.; Bulos, M.; Altieri, E.; Domínguez, J.

    2015-07-01

    Broomrape, caused by Orobanche cumana, has affected sunflowers since the early 20th century in Eastern Europe. Currently, it limits sunflower oil production in Southern and Eastern Europe and in some areas of Asia, causing around 50% seed losses when susceptible hybrids are grown. Covered in this review are aspects such as: biological processes that are common to Orobanche spp. and/or particular to O. cumana in sunflower, genetic resistance and its mechanisms, races of the parasite identified in different countries throughout the time and their increasing virulence, and breeding for resistance to some herbicides as a novel control option. The main purpose is to present an updated and, as far as possible, complete picture of the way both the parasitic weed and its host crop have evolved in time, and how they co-exist in the current agriculture. Additionally, we propose a system for determining the races of the parasite that can be internationally adopted from now. In the context of minimal harmful effects on the environment, changing patterns of land use in farming systems, and global environment changes, the final goal of this work is to provide all those interested in parasites from field crops and their integrated management compiled information on the sunflower – O. cumana system as a case study. (Author)

  8. Sunflower seed for human consumption as a substrate for the growth of mycopopulations

    Directory of Open Access Journals (Sweden)

    Škrinjar Marija M.

    2012-01-01

    Full Text Available These mycological investigations are implicating samples of protein sunflower seed from regular cultivation in the Vojvodina Province. Samples are examined in different stages of production: reception in the silo, separation of massive fraction on peeler and then peeling, kernel after peeling, hull, final product, i.e. kernels separated from visible impurities on conveyor bel, that are later manually divided in two fractions - a seemingly whole, undamaged kernels, without change of colour, and b seemingly damaged kernels, broken, with change of colour. For the determination of viable count of moulds and their isolation, two different media are used in parallel: Sabouraud maltose agar (SMA and malt/yeast extract with 50% of glucose (MY50G, favourable for growth of xerophilic moulds. All samples tested were contaminated with fungi. Total viable mould count per seed varied from 1.6 (SMA respecting 1.3 (MY50G on reception, to 5.6 (SMA and 7.5 (MY50G cfu/seed in visually damaged sunflower kernels (final product. From seeds, kernels and hull, numerous moulds were isolated, belonging to 8 genera and 13 species (Alternaria alternata, Arthrinium phaeospermum, Aspergillus candidus, A. flavus, A. niger, A. ochraceus, A. versicolor, A. wentii, Cladosporium cladosporioides, Eurotium herbariorum, Penicillium aurantiogriseum, Rhizopus stolonifer and Trichoderma harzianum. Alternaria alternata, Aspergillus flavus, A.ochraceus, A. versicolor and Eurotium herbariorum were isolated on both media. Aspergillus candidus, A. versicolor, C. Cladosporioides, P. aurantiogriseum and T. harzianum were isolated only on SMA, while A. niger, A. wentii and R. stolonifer were exclusively isolated on MY50G. Most ubiquitous species is A. alternata, which is isolated from all tested samples, while A. candidus, C. cladosporioides and T. harzianum were isolated from sunflower seed on reception in silo, using SMA medium.

  9. Hybridization and management of oak populations

    Science.gov (United States)

    Oliver Gailing

    2017-01-01

    Hybridization can result in the transfer of adaptations among species and may contribute to speciation processes. On the other hand, hybridization can also result in a loss of species diversity due to asymmetric gene flow between species (genetic swamping) and in low hybrid fitness. An understanding of the outcomes of interspecific hybridization is crucial for the...

  10. Population genetic structure and hybridization patterns in the cryptic sister species Chironomus riparius and Chironomus piger across differentially polluted freshwater systems.

    Science.gov (United States)

    Pedrosa, João A M; Cocchiararo, Berardino; Verdelhos, Tiago; Soares, Amadeu M V M; Pestana, João L T; Nowak, Carsten

    2017-07-01

    Chironomids are an integral and functionally important part of many freshwater ecosystems. Yet, to date, there is limited understanding of their microevolutionary processes under chemically polluted natural environments. In this study, we investigated the genetic variation within populations of the ecotoxicological model species Chironomus riparius and its cryptic sister species Chironomus piger at 18 metal-contaminated and reference sites in northwestern Portugal. Microsatellite analysis was conducted on 909 samples to answer if metal contamination affects genetic variation in natural chironomid populations as previously suggested from controlled laboratory experiments. Similarly high levels of genetic diversity and significant but weak genetic substructuring were found across all sites and temporal replicates, with no effects of metal contamination on the genetic variation or species' abundance, although C. piger tended to be less frequent at highly contaminated sites. Our results indicate that high levels of gene flow and population dynamic processes may overlay potential pollutant effects. At least for our study species, we conclude that the "genetic erosion hypothesis", which suggests that chemical pollution will reduce genome-wide genetic variability in affected populations, does not hold under natural conditions. Interestingly, our study provides evidence of successful hybridization between the two sister species under natural conditions. Copyright © 2017 Elsevier Inc. All rights reserved.

  11. Marine Fish Hybridization

    KAUST Repository

    He, Song

    2017-04-01

    Natural hybridization is reproduction (without artificial influence) between two or more species/populations which are distinguishable from each other by heritable characters. Natural hybridizations among marine fishes were highly underappreciated due to limited research effort; it seems that this phenomenon occurs more often than