43 results on '"Darkó É"'
Search Results
2. Light spectrum modifies the drought-induced changes of glutathione and free amino acid levels in wheat
- Author
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Gyugos, M., Ahres, M., Gulyás, Z., Szalai, G., Darkó, É., Mednyánszky, Z., Dey, N., Kar, R. K., Simon-Sarkadi, L., and Kocsy, G.
- Published
- 2021
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3. Growth light substantially affects both primary and secondary metabolic processes in Catharanthus roseus plants
- Author
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GHOLIZADEH, F., primary, DARKÓ, É., additional, BENCZÚR, K., additional, HAMOW, K.Á., additional, DERNOVICS, M., additional, NAGY, K., additional, JANDA, T., additional, RADY, M.R., additional, GOHARI, G., additional, PÁL, M., additional, LE, V.N., additional, and SZALAI, G., additional
- Published
- 2023
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4. Approaches to Educational Activities and Construction of an Informatics Curriculum
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Darko Etinger, Marina Diković, and Hrvoje Alilović
- Subjects
american customer satisfaction index (acsi) ,computer science curriculum ,ict ,informatics ,student satisfaction ,Education - Abstract
The research section of the paper explores elementary school students’ satisfaction with informatics. This research was carried out using the American Customer Satisfaction Index (ACSI). Four subscales were used: Expectation, Satisfaction, Quality, and Values. The number of Croatian elementary school pupils investigated (from Brod-Posavina County) is 135 (N). Research results show that pupils have high expectations of informatics, including that it will progressively meet their expectations and help them to receive a quality education. It can also be concluded that the problems once faced by students, such as classroom and equipment quality, are becoming much smaller compared to previous years.
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- 2024
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5. Photosynthetic responses of a wheat (Asakaze)–barley (Manas) 7H addition line to salt stress
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Szopkó, D., Darkó, É., Molnár, I., Kruppa, K., Háló, B., Vojtkó, A., Molnár-Láng, M., and Dulai, S.
- Published
- 2017
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6. Altered Light Response of Xanthophyll Cycle in Herbicide-Resistant Erigeron Canadensis Biotypes in the Presence of Paraquat
- Author
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Váradi, Gy., Darkó, É., Lehoczki, E., and Garab, G., editor
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- 1998
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7. Lowered Xanthophyll Cycle Capacity Accompanying Triazine Resistance of Weeds
- Author
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Ertli, T., Polyánka, H., Váradi, Gy., Darkó, É., Lehoczki, E., and Garab, G., editor
- Published
- 1998
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8. Regeneration of fertile wheat (Triticum aestivum) plants from isolated zygotes using wheat microspore culture as nurse cells
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Bakos, F., Darkó, É., Pónya, Zs., and Barnabás, B.
- Published
- 2003
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9. Session 10 Photosynthesis
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Adamska, I., Kloppstech, K., Andersson, B., Bubolo, L. S., Sharkova, V. E., Büchel, C., Garab, G., Budagovskaya, N. V., Chaika, M. T., Savchenko, G. E., Abramchik, L. M., Serduchenko, E. V., Kluchareva, E. A., Fridlyand, L. E., Giardi, M. T., Komenda, J., Masojídek, J., Kučera, T., Hodges, M., Gucci, R., Everard, J. D., Flore, J. A., Loescher, W. H., Hák, R., Janáček, J., Haumann, J., Bolhar-Nordenkampf, H. R., Hiltonen, T., Karlsson, J., Palmqvist, K., Clarke, A., Samuelsson, G., Hudák, J., Masarovičová, E., Ivanchenko, V. M., Janda, T., Szalai, G., Páldi, E., Szigeti, Z., Jovanič, B. R., Bogdanovič, M. T., Tomaševič, M. N., Keerberg, O., Gardeström, P., Vanova, H. I., Keerberg, H., Pärnik, T., Kissimon, J., Lásztity, D., Páldi, E., Kochubey, S. M., Kornyushenko, G. A., Sapozhnikov, D. I., Kovács, J., Csapó, B., Páldi, E., Böddi, B., Kozklowska, B., Maleszewski, S., Krupa, Z., Öquist, G., Siedlecka, A., Lacuesta, M., Gonzalez-Moro, B., Diaz, A., Gonzalez-Murua, C., Muánoz-Rueda, A., Makeev, A. V., Maksymiec, W., Baszyński, T., Da Silva, J. Marques, Arrabaça, M. C., Muzafarov, E. N., Nazarova, G. N., Davies, C. F., Nazarova, G. N., Muzafarov, E. N., Lyubimov, V. Yu., Davies, C. F., Nogués, S., Baker, N. R., Nosticzius, Á., Nyitrai, P., Sárvári, É., Ungár, D., Lang, F., Ottander, Christina, Öquist, Gunnar, Ouzounidou, G., Pádua, M., Casimiro, A., Pamer, R., Perathoner, C., Bauer, H., Panković, D., Kevrešan, S., Plesničar, M., Sakač, Z., Ćupina, T., Vapa, LJ., Pazurkiewicz-Kocot, K., Peter, S., Roos, M., Schäfer, C., Poot, P., PospíŠilová, J., Čatský, J., Synková, H., Wilhelmová, N., Postl, W., Donis, Klune, R., Bolhar-Nordenkampf, H. R., Kamnalrut, A., Ramazanov, Z., Henk, M. C., Sosa, P. A., Del Rio, M. Jimenez, Gomez-Pincheti, J-L., Reina, G. Garcia, Richter, M., Goss, R., Nguyen, D. T., Wild, A., Romanowska, E., Albertsson, P. -A., Russell, A. W., Schiefthaler, U., Bolhár-Nordenkampf, H. R., Critchley, C., Meister, M., Šantrůček, J., Květoň, J., šimková, M., Roháček, K., Sárvári, É., Nyitrai, P., Scagliarini, S., Trost, P., Pupillo, P., Scheibe, R., Selga, M., Selga, T., Shevchenko, O. V., Panchenko, A. P., Siedlecka, A., Krupa, Z., Baszyński, T., Skórzyńska, E., Špunda, V., Čajánek, M., Kalina, J., Lachetová, I., Sundberg, B., Renhorn, K-E, Esseen, P-A, Sundin, U., Ögren, E., Tamás, L., Sárvári, É., Vácha, F., Durchan, M., Van Loven, K., Synková, H., Valcke, R., Vapaavuori, E. M., Pennanen, A. H., Ruuska, S. A., Vuorinen, A. H., Váradi, Gy., Darkó, É., Pölös, E., Lehoczki, E., Veljović-Jovanović, S., Vučinić, Ž., Heber, U., Bilger, W., Venema, J. H., Van Hasselt, P. R., Vigara, A. J., García-Sánchez, M. I., Gómez-Moreno, C., Vega, J. M., Vilchez, C., Vega, J. M., Vogg, G., Heim, R., Hansen, J., Schäfer, C., Beck, E., Waloszek, A., Sikorska, E., Wieckowski, S., Wilhelmová, N., Kutík, J., Šesták, Z., Wojcieska-Wyskupajtys, U., Zillinger, A., Haumann, J., and Bolhár-Nordenkampf, H. R.
- Published
- 1994
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10. Session 20 Plant-herbicide interaction
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Bujtás, K., Chodová, D., Mikulka, J., Kočová, M., JanáČek, J., Conrad, R., Wilhelm, C., Darkó, É., Lehoczki, E., Szigeti, Z., Forlani, G., Lejczak, B., Kafarski, P., Gonzalez, A., Gonzalez-Murua, C., Royuela, M., Hernandez A., Becerril, J. M., Kereckj, B., Zaric, L. J., Stefanovic, L., Laskay, G., Váradi, Gy., Pölös, E., Lichtenthaler, H. K., Golz, A., Martinez, J., Vidal, D., Simon, E., Morderer, E. Yu., Khodeeva, L. V., Piñol, R., Simon, E., Stefanovic, L., Janjic, V., Marisavljevic, D., Jovanovic, L. J., Stikic, R., Pekic, S., Vanoorschot, J. L. P., Van Rensen, Jack J. S., Curwiel, Victor B., Vinnichenko, A. N., and Shtemenko, N. I.
- Published
- 1994
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11. Factors playing role in heat acclimation processes in barley and oat plants
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DARKÓ, É., primary, KHALIL, R., additional, ELSAYED, N., additional, PÁL, M., additional, HAMOW, K.Á., additional, SZALAI, G., additional, TAJTI, J., additional, NGUYEN, Q.T., additional, NGUYEN, N.T., additional, LE, V.N., additional, and JANDA, T., additional
- Published
- 2019
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12. Heat acclimation of photosynthesis in wheat genotypes of different origin
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Végh, B., primary, Marček, T., additional, Karsai, I., additional, Janda, T., additional, and Darkó, É., additional
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- 2018
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13. Antimicrobial resistance and self-medication: A survey among first-year health students at a tertiary institution in Ghana
- Author
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Darko, E. and Owusu-Ofori, A.
- Published
- 2020
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14. INFLUENCES TOURANIENNES SUR L'ÉVOLUTION DE L'ART MILITAIRE DES GRECS, DES ROMAINS ET DES BYZANTINS
- Author
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Darkó, E.
- Published
- 1935
15. INFLUENCES TOURANIENNES SUR L'ÉVOLUTION DE L'ART MILITAIRE DES GRECS, DES ROMAINS ET DES BYZANTINS
- Author
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Darkó, E.
- Published
- 1937
16. Urban sprawl and microclimate in the Ga East municipality of Ghana
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Kwasi Frimpong, Darko Eugene Atiemo, and E.J. Van Etten
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Microclimate ,Rainfall ,Temperature ,Urban sprawl ,Ga east municipality ,Science (General) ,Q1-390 ,Social sciences (General) ,H1-99 - Abstract
Climatic elements such as temperature and rainfall provide great and unquantifiable benefits to human health. However, rapid urban sprawl has the tendency to undermine these health consequences. The relationship between urban sprawl and microclimate in the Ga East Municipality has been assessed to present the extent of sprawl that inhibit temperature and rainfall in recent times. Methodologically, satellite imagery and meteorological data (minimum and maximum temperature and rainfall) from 1990 to 2020 were used. The results indicate that rapid urban sprawl in recent times has significantly undermined the local climate through land use and land cover changes. There was strong statistical relationships between temperature and built-up areas (p < 0.05), grass/shrub cover (p < 0.04) and all vegetation cover (p < 0.03). There was also strong statistical relationship between rainfall and built-up areas (p < 0.03), grass/shrub cover (p < 0.04) and all vegetation (p < 0.02). Thus, expansion in built up areas and reduced grass/shrub cover led to increases in temperature, rainfall and surface water run off while reduction in all vegetation led to increase in both temperature and rainfall. These changes in climate brought about by urban sprawl will affect crop production, increase cataclysmic floods as well as growth of some harmful insects. There is the need for the amalgamation of urban growth and climate change into spatial planning through an all-embracing approach.
- Published
- 2022
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17. Improved Cold and Drought Tolerance of Doubled Haploid Maize Plants Selected for Resistance to Prooxidant tert-Butyl Hydroperoxide
- Author
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Darkó, É., primary, Fodor, J., additional, Dulai, S., additional, Ambrus, H., additional, Szenzenstein, A., additional, Király, Z., additional, and Barnabás, B., additional
- Published
- 2011
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18. A cytological study on aluminium-treated wheat anther cultures resulting in plants with increased Al tolerance
- Author
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Bakos, F., primary, Darkó, É., additional, Ascough, G., additional, Gáspár, L., additional, Ambrus, H., additional, and Barnabás, B., additional
- Published
- 2008
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19. IT as a part of intellectual capital and its impact on the performance of business entities
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Ksenija Černe and Darko Etinger
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information technology (IT) ,partial least squares structural equation modeling (PLS-SEM) ,importance-performance analysis ,intellectual capital ,business performance ,Applied mathematics. Quantitative methods ,T57-57.97 - Abstract
The relevant literature generally views intellectual capital as comprising three components – human, relational and structural capital. These components are identified and classified by their sub–components, meaning that human, relational and structural capital cannot be observed separately. Whereas human capital is most often treated for its frequent identification with intellectual capital and less often with relational capital, this paper we discuss structural capital and, in particular, as one of the sub–components that refers to information technology (IT). The relevant literature views an IT sub– component as an integral part of almost any classification of structural capital. IT items are intertwined with and are complementary to specific human and relational capital items, and it is common to observe them under the same light. However, because of its presumed importance and influence on other forms of intellectual capital and financial performance, this paper will derive IT from structural capital and treat it as a component that supports the other ones. We still assume that intellectual capital is a logical entity consisting of the three mentioned components, but our intention is also to highlight and prove the importance of IT. Our assumptions were tested in a model under several hypotheses, and most of them were supported. The model is derived from a study conducted on a random sample of Croatian businesses, by applying PLS–SEM and importance–performance analysis.
- Published
- 2016
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20. Application of best estimate plus uncertainty in review of research reactor safety analysis
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Adu Simon, Horvatovic Ivan, Darko Emmanuel O., Emi-Reynolds Geoffrey, and D'auria Francesco
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best estimate plus uncertainty ,research reactor ,RELAP5-3D ,safety analysis ,Nuclear and particle physics. Atomic energy. Radioactivity ,QC770-798 - Abstract
To construct and operate a nuclear research reactor, the licensee is required to obtain the authorization from the regulatory body. One of the tasks of the regulatory authority is to verify that the safety analysis fulfils safety requirements. Historically, the compliance with safety requirements was assessed using a deterministic approach and conservative assumptions. This provides sufficient safety margins with respect to the licensing limits on boundary and operational conditions. Conservative assumptions were introduced into safety analysis to account for the uncertainty associated with lack of knowledge. With the introduction of best estimate computational tools, safety analyses are usually carried out using the best estimate approach. Results of such analyses can be accepted by the regulatory authority only if appropriate uncertainty evaluation is carried out. Best estimate computer codes are capable of providing more realistic information on the status of the plant, allowing the prediction of real safety margins. The best estimate plus uncertainty approach has proven to be reliable and viable of supplying realistic results if all conditions are carefully followed. This paper, therefore, presents this concept and its possible application to research reactor safety analysis. The aim of the paper is to investigate the unprotected loss-of-flow transients "core blockage" of a miniature neutron source research reactor by applying best estimate plus uncertainty methodology. The results of our calculations show that the temperatures in the core are within the safety limits and do not pose any significant threat to the reactor, as far as the melting of the cladding is concerned. The work also discusses the methodology of the best estimate plus uncertainty approach when applied to the safety analysis of research reactors for licensing purposes.
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- 2015
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21. Prediction of attendance at fitness center: a comparison between theory of planned behavior, social cognitive theory, and physical activity maintenance theory
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Darko eJekauc
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Exercise ,Maintenance ,physical activity ,prediction ,exercise psychology ,Psychology ,BF1-990 - Abstract
In the processes of physical activity (PA) maintenance specific predictors are effective, which differ from other stages of PA development. Recently, Physical Activity Maintenance Theory (PAMT) was specifically developed for prediction of PA maintenance. The aim of the present study was to evaluate the predictability of the future behavior by the PAMT and compare it with the Theory of Planned Behavior (TPB) and Social Cognitive Theory (SCT). Participation rate in a fitness center was observed for 101 college students (53 female) aged between 19 and 32 years (M = 23.6; SD = 2.9) over 20 weeks using a magnetic card. In order to predict the pattern of participation TPB, SCT and PAMT were used. A latent class zero-inflated Poisson growth curve analysis identified two participation patterns: regular attenders and intermittent exercisers. SCT showed the highest predictive power followed by PAMT and TPB. Impeding aspects as life stress and barriers were the strongest predictors suggesting that overcoming barriers might be an important aspect for exercise maintenance. Self-efficacy, perceived behavioral control, and social support could also significantly differentiate between the participation patterns.
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- 2015
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22. LuxR solos in Photorhabdus species
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Sophie eBrameyer, Darko eKresovic, Helge B. Bode, and Ralf eHeermann
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Quorum Sensing ,cell-cell communication ,LuxR solos ,quorum quenching ,entomopathogenic bacteria ,Microbiology ,QR1-502 - Abstract
Bacteria communicate via small diffusible molecules to mediate group-coordinated behavior, a process designated as quorum sensing. The basic molecular quorum sensing system of Gram-negative bacteria consists of a LuxI-type autoinducer synthase producing acyl-homoserine lactones (AHLs) as signaling molecules, and a LuxR-type receptor detecting the AHLs to control expression of specific genes. However, many proteobacteria possess one or more unpaired LuxR-type receptors that lack a cognate LuxI-like synthase, referred to as LuxR solos. The enteric and insect pathogenic bacteria of the genus Photorhabdus harbor an extraordinary high number of LuxR solos, more than any other known bacteria, and all lack a LuxI-like synthase. Here, we focus on the presence and the different types of LuxR solos in the three known Photorhabdus species using bioinformatics analyses. Generally, the N-terminal signal-binding domain of LuxR-type receptors sensing AHLs have a motif of six conserved amino acids that is important for binding and specificity of the signaling molecule. However, this motif is altered in the majority of the Photorhabdus-specific LuxR solos, suggesting the use of other signaling molecules than AHLs for intra-species communication. Furthermore, all Photorhabdus species contain at least one LuxR solo with an intact AHL-binding motif, which might allow the ability to sense AHLs of other bacteria. Moreover, all three species have high AHL-degrading activity caused by the presence of different AHL-lactonases and AHL-acylases, revealing a high quorum quenching activity against other bacteria. However, the majority of the other LuxR solos in Photorhabdus have a N-terminal so-called PAS4-domain instead of an AHL-binding domain, containing different amino acid motifs than the AHL-sensors, which potentially allows the recognition of a highly variable range of signaling molecules that can be sensed apart from AHLs. These PAS4-LuxR solos are supposed to be involved in host sensin
- Published
- 2014
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23. DArTseq genotyping facilitates identification of Aegilops biuncialis chromatin introgressed into bread wheat Mv9kr1.
- Author
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Gaál E, Farkas A, Türkösi E, Kruppa K, Szakács É, Szőke-Pázsi K, Kovács P, Kalapos B, Darkó É, Said M, Lampar A, Ivanizs L, Valárik M, Doležel J, and Molnár I
- Subjects
- Genotype, Genetic Introgression, Genetic Markers, Genotyping Techniques, Plant Breeding methods, Chromosome Mapping, Triticum genetics, Aegilops genetics, Chromatin genetics, Chromatin metabolism, Chromosomes, Plant genetics, Genome, Plant
- Abstract
Wild wheat relative Aegilops biuncialis offers valuable traits for crop improvement through interspecific hybridization. However, gene transfer from Aegilops has been hampered by difficulties in detecting introgressed U
b - and Mb -genome chromatin in the wheat background at high resolution. The present study applied DArTseq technology to genotype two backcrossed populations (BC382, BC642) derived from crosses of wheat line Mv9kr1 with Ae. biuncialis accession, MvGB382 (early flowering and drought-tolerant) and MvGB642 (leaf rust-resistant). A total of 11,952 Aegilops-specific Silico-DArT markers and 8,998 wheat-specific markers were identified. Of these, 7,686 markers were assigned to Ub -genome chromosomes and 4,266 to Mb -genome chromosomes and were ordered using chromosome scale reference assemblies of hexaploid wheat and Ae. umbellulata. Ub -genome chromatin was detected in 5.7% of BC382 and 22.7% of BC642 lines, while 88.5% of BC382 and 84% of BC642 lines contained Mb -genome chromatin, predominantly the chromosomes 4Mb and 5Mb . The presence of alien chromatin was confirmed by microscopic analysis of mitotic metaphase cells using GISH and FISH, which allowed precise determination of the size and position of the introgression events. New Mv9kr1-Ae. biuncialis MvGB382 4Mb and 5Mb disomic addition lines together with a 5DS.5DL-5Mb L recombination were identified. A possible effect of the 5Mb L distal region on seed length has also been observed. Moreover, previously developed Mv9kr1-MvGB642 introgression lines were more precisely characterized. The newly developed cytogenetic stocks represent valuable genetic resources for wheat improvement, highlighting the importance of utilizing diverse genetic materials to enhance wheat breeding strategies., (© 2024. The Author(s).)- Published
- 2024
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24. DArTseq genotyping facilitates the transfer of "exotic" chromatin from a Secale cereale × S. strictum hybrid into wheat.
- Author
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Szőke-Pázsi K, Kruppa K, Tulpová Z, Kalapos B, Türkösi E, Gaál E, Darkó É, Said M, Farkas A, Kovács P, Ivanizs L, Doležel J, Rabanus-Wallace MT, Molnár I, and Szakács É
- Abstract
Cultivated and wild species of the genus rye ( Secale ) are important but underexploited gene sources for increasing the genetic diversity of bread wheat. Gene transfer is possible via bridge genetic materials derived from intergeneric hybrids. During this process, it is essential to precisely identify the rye chromatin in the wheat genetic background. In the present study, backcross generation BC
2 F8 from a cross between Triticum aestivum (Mv9kr1) and S. cereanum ('Kriszta,' a cultivar from the artificial hybrid of S. cereale and S. strictum ) was screened using in-situ hybridization (GISH and FISH) and analyzed by DArTseq genotyping in order to select potentially agronomically useful genotypes for prebreeding purposes. Of the 329,267 high-quality short sequence reads generated, 27,822 SilicoDArT and 8,842 SNP markers specific to S. cereanum 1R-7R chromosomes were identified. Heatmaps of the marker densities along the 'Lo7' rye reference pseudomolecules revealed subtle differences between the FISH- and DArTseq-based results. This study demonstrates that the "exotic" rye chromatin of S. cereanum introgressed into wheat can be reliably identified by high-throughput DArTseq genotyping. The Mv9kr1-'Kriszta' addition and translocation lines presented here may serve as valuable prebreeding genetic materials for the development of stress-tolerant or disease-resistant wheat varieties., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest. The author(s) declared that they were an editorial board member of Frontiers, at the time of submission. This had no impact on the peer review process and the final decision., (Copyright © 2024 Szőke-Pázsi, Kruppa, Tulpová, Kalapos, Türkösi, Gaál, Darkó, Said, Farkas, Kovács, Ivanizs, Doležel, Rabanus-Wallace, Molnár and Szakács.)- Published
- 2024
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25. A chromosome arm from Thinopyrum intermedium × Thinopyrum ponticum hybrid confers increased tillering and yield potential in wheat.
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Türkösi E, Szakács É, Ivanizs L, Farkas A, Gaál E, Said M, Darkó É, Cséplő M, Mikó P, Doležel J, Molnár-Láng M, Molnár I, and Kruppa K
- Abstract
Tiller number is a key component of wheat plant architecture having a direct impact on grain yield. Because of their viability, biotic resistance, and abiotic stress tolerance, wild relative species are a valuable gene source for increasing wheat genetic diversity, including yield potential. Agropyron glael , a perennial hybrid of Thinopyrum intermedium and Th. ponticum , was created in the 1930s. Recent genome analyses identified five evolutionarily distinct subgenomes (J, J
st , Jvs , Jr , and St), making A. glael an important gene source for transferring useful agronomical traits into wheat. During a bread wheat × A. glael crossing program, a genetically stable translocation line, WT153397, was developed. Sequential in situ hybridizations (McGISH) with J-, St-, and D-genomic DNA probes and pSc119.2, Afa family, pTa71, and (GAA)7 DNA repeats, as well as molecular markers specific for the wheat 6D chromosome, revealed the presence of a 6DS.6Jvs Robertsonian translocation in the genetic line. Field trials in low-input and high-input breeding nurseries over four growing seasons demonstrated the Agropyron chromosome arm's high compensating ability for the missing 6DL, as spike morphology and fertility of WT153397 did not differ significantly from those of wheat parents, Mv9kr1 and 'Mv Karizma.' Moreover, the introgressed 6Jvs chromosome arm significantly increased the number of productive tillers, resulting in a significantly higher grain yield potential compared to the parental wheat cultivars. The translocated chromosome could be highly purified by flow cytometric sorting due to the intense fluorescent labeling of (GAA)7 clusters on the Thinopyrum chromosome arm, providing an opportunity to use chromosome genomics to identify Agropyron gene variant(s) responsible for the tillering capacity. The translocation line WT153397 is an important genetic stock for functional genetic studies of tiller formation and useful breeding material for increasing wheat yield potential. The study also discusses the use of the translocation line in wheat breeding., Supplementary Information: The online version contains supplementary material available at 10.1007/s11032-024-01439-y., Competing Interests: Conflict of interestThe authors declare no competing interests., (© The Author(s) 2024.)- Published
- 2024
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26. Chromosome genomics facilitates the marker development and selection of wheat-Aegilops biuncialis addition, substitution and translocation lines.
- Author
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Farkas A, Gaál E, Ivanizs L, Blavet N, Said M, Holušová K, Szőke-Pázsi K, Spitkó T, Mikó P, Türkösi E, Kruppa K, Kovács P, Darkó É, Szakács É, Bartoš J, Doležel J, and Molnár I
- Subjects
- In Situ Hybridization, Fluorescence, Chromosomes, Plant genetics, Translocation, Genetic, Genetic Markers, Genomics, Triticum genetics, Aegilops genetics
- Abstract
The annual goatgrass, Aegilops biuncialis is a rich source of genes with considerable agronomic value. This genetic potential can be exploited for wheat improvement through interspecific hybridization to increase stress resistance, grain quality and adaptability. However, the low throughput of cytogenetic selection hampers the development of alien introgressions. Using the sequence of flow-sorted chromosomes of diploid progenitors, the present study enabled the development of chromosome-specific markers. In total, 482 PCR markers were validated on wheat (Mv9kr1) and Ae. biuncialis (MvGB642) crossing partners, and 126 on wheat-Aegilops additions. Thirty-two markers specific for U- or M-chromosomes were used in combination with GISH and FISH for the screening of 44 Mv9kr1 × Ae. biuncialis BC
3 F3 genotypes. The predominance of chromosomes 4M and 5M, as well as the presence of chromosomal aberrations, may indicate that these chromosomes have a gametocidal effect. A new wheat-Ae. biuncialis disomic 4U addition, 4M(4D) and 5M(5D) substitutions, as well as several introgression lines were selected. Spike morphology and fertility indicated that the Aegilops 4M or 5M compensated well for the loss of 4D and 5D, respectively. The new cytogenetic stocks represent valuable genetic resources for the introgression of key genes alleles into wheat., (© 2023. The Author(s).)- Published
- 2023
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27. UPLC-ESI-QTOF-MS assisted targeted metabolomics to study the enrichment of vinca alkaloids and related metabolites in Catharanthus roseus plants grown under controlled LED environment.
- Author
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Nagy K, Darkó É, Szalai G, Janda T, Jókai Z, Ladányi M, Rady MR, and Dernovics M
- Subjects
- Vinblastine metabolism, Vincristine, Metabolomics, Vinca Alkaloids analysis, Vinca Alkaloids metabolism, Catharanthus metabolism, Antineoplastic Agents metabolism
- Abstract
Enrichment of pharmaceutically important vinca alkaloids, vinblastine and vincristine, in the leaves of Madagascar periwinkle (Catharanthus roseus) plants through different pre- or postharvest treatments or cultivation conditions, e.g., exposing the plants to UV-irradiation, has been in focus for decades. Controlled LED environment in the visible light range offers the possibility of monitoring the changes in the concentration of metabolites in the vinca alkaloid-related pathway without involving UV-related abiotic stress. In the frame of our targeted metabolomics approach, 64 vinca alkaloids and metabolites were screened with the help of a UPLC-ESI-QTOF-MS instrumental setup from the leaf extracts of C. roseus plants grown in chambers under control (medium light), low light, and high blue / high red/ high far-red conditions. Out of the 14 metabolites that could be assigned either unambiguously with authentic standards or tentatively with high resolution mass spectrometry-based methods, all three dimer vinca alkaloids, that is, 3',4'-anhydrovinblastine, vinblastine and vincristine showed an at least nine-fold enrichment under high blue irradiation when compared with the control conditions: final concentrations of 961 mg kg
-1 dry weight, 33.8 mg kg-1 dry weight, and 11.7 mg kg-1 dry weight could be achieved, respectively. As supported by multivariate statistical analysis, the key metabolites of the vinca alkaloid pathway were highly represented among the metabolites that were specifically stimulated by high blue light application., Competing Interests: Declaration of Competing Interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: Mihály Dernovics reports a relationship with the Hungarian Academy of Sciences (MTA) and the Egyptian Academy of Scientific Research and Technology (ASRT) that includes: funding grants and travel reimbursement. Mohamed Ramadan Rady reports a relationship with the Hungarian Academy of Sciences (MTA) and the Egyptian Academy of Scientific Research and Technology (ASRT) that includes: funding grants and travel reimbursement., (Copyright © 2023 The Authors. Published by Elsevier B.V. All rights reserved.)- Published
- 2023
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28. D27-LIKE1 isomerase has a preference towards trans/cis and cis/cis conversions of carotenoids in Arabidopsis.
- Author
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Gulyás Z, Moncsek B, Hamow KÁ, Stráner P, Tolnai Z, Badics E, Incze N, Darkó É, Nagy V, Perczel A, Kovács L, and Soós V
- Subjects
- beta Carotene metabolism, Isomerases chemistry, Isomerases genetics, Isomerases metabolism, Carotenoids metabolism, Arabidopsis genetics, Arabidopsis metabolism
- Abstract
Carotenoids contribute to a variety of physiological processes in plants, functioning also as biosynthesis precursors of ABA and strigolactones (SLs). SL biosynthesis starts with the enzymatic conversion of all-trans-β-carotene to 9-cis-β-carotene by the DWARF27 (D27) isomerase. In Arabidopsis, D27 has two closely related paralogs, D27-LIKE1 and D27-LIKE2, which were predicted to be β-carotene-isomerases. In the present study, we characterised D27-LIKE1 and identified some key aspects of its physiological and enzymatic functions in Arabidopsis. d27-like1-1 mutant does not display any strigolactone-deficient traits and exhibits a substantially higher 9-cis-violaxanthin content, which is accompanied by a slightly higher ABA level. In vitro feeding assays with recombinant D27-LIKE1 revealed that the protein exhibits affinity to all β-carotene isoforms but with an exclusive preference towards trans/cis conversions and the interconversion between 9-cis, 13-cis and 15-cis-β-carotene forms, and accepts zeaxanthin and violaxanthin as substrates. Finally, we present evidence showing that D27-LIKE1 mRNA is phloem mobile and D27-LIKE1 is an ancient isomerase with a long evolutionary history. In summary, we demonstrate that D27-LIKE1 is a carotenoid isomerase with multi-substrate specificity and has a characteristic preference towards the catalysation of cis/cis interconversion of carotenoids. Therefore, D27-LIKE1 is a potential regulator of carotenoid cis pools and, eventually, SL and ABA biosynthesis pathways., (© 2022 Society for Experimental Biology and John Wiley & Sons Ltd.)
- Published
- 2022
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29. Identification of New QTLs for Dietary Fiber Content in Aegilops biuncialis .
- Author
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Ivanizs L, Marcotuli I, Rakszegi M, Kalapos B, Szőke-Pázsi K, Farkas A, Türkösi E, Gaál E, Kruppa K, Kovács P, Darkó É, Szakács É, Said M, Cápal P, Doležel J, Gadaleta A, and Molnár I
- Subjects
- Dietary Fiber, Genes, Plant, Plant Breeding, Quantitative Trait Loci, Triticum genetics, Water, Aegilops genetics, beta-Glucans
- Abstract
Grain dietary fiber content is an important health-promoting trait of bread wheat. A dominant dietary fiber component of wheat is the cell wall polysaccharide arabinoxylan and the goatgrass Aegilops biuncialis has high β-glucan content, which makes it an attractive gene source to develop wheat lines with modified fiber composition. In order to support introgression breeding, this work examined genetic variability in grain β-glucan, pentosan, and protein content in a collection of Ae. biuncialis . A large variation in grain protein and edible fiber content was revealed, reflecting the origin of Ae. biuncialis accessions from different eco-geographical habitats. Association analysis using DArTseq-derived SNPs identified 34 QTLs associated with β-glucan, pentosan, water-extractable pentosan, and protein content. Mapping the markers to draft chromosome assemblies of diploid progenitors of Ae. biuncialis underlined the role of genes on chromosomes 1M
b , 4Mb , and 5Mb in the formation of grain β-glucan content, while other QTLs on chromosome groups 3, 6, and 1 identified genes responsible for total- and water-extractable pentosan content. Functional annotation of the associated marker sequences identified fourteen genes, nine of which were identified in other monocots. The QTLs and genes identified in the present work are attractive targets for chromosome-mediated gene transfer to improve the health-promoting properties of wheat-derived foods.- Published
- 2022
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30. Elongation factor TFIIS is essential for heat stress adaptation in plants.
- Author
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Szádeczky-Kardoss I, Szaker HM, Verma R, Darkó É, Pettkó-Szandtner A, Silhavy D, and Csorba T
- Subjects
- Heat-Shock Response, RNA Polymerase II metabolism, Transcription, Genetic, Transcriptional Elongation Factors metabolism, Arabidopsis genetics, Arabidopsis physiology, Transcription Factors, General metabolism
- Abstract
Elongation factor TFIIS (transcription factor IIS) is structurally and biochemically probably the best characterized elongation cofactor of RNA polymerase II. However, little is known about TFIIS regulation or its roles during stress responses. Here, we show that, although TFIIS seems unnecessary under optimal conditions in Arabidopsis, its absence renders plants supersensitive to heat; tfIIs mutants die even when exposed to sublethal high temperature. TFIIS activity is required for thermal adaptation throughout the whole life cycle of plants, ensuring both survival and reproductive success. By employing a transcriptome analysis, we unravel that the absence of TFIIS makes transcriptional reprogramming sluggish, and affects expression and alternative splicing pattern of hundreds of heat-regulated transcripts. Transcriptome changes indirectly cause proteotoxic stress and deterioration of cellular pathways, including photosynthesis, which finally leads to lethality. Contrary to expectations of being constantly present to support transcription, we show that TFIIS is dynamically regulated. TFIIS accumulation during heat occurs in evolutionary distant species, including the unicellular alga Chlamydomonas reinhardtii, dicot Brassica napus and monocot Hordeum vulgare, suggesting that the vital role of TFIIS in stress adaptation of plants is conserved., (© The Author(s) 2022. Published by Oxford University Press on behalf of Nucleic Acids Research.)
- Published
- 2022
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31. Crosstalk between Light- and Temperature-Mediated Processes under Cold and Heat Stress Conditions in Plants.
- Author
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Janda T, Prerostová S, Vanková R, and Darkó É
- Subjects
- Plants metabolism, Plants radiation effects, Signal Transduction, Sunlight, Cold-Shock Response, Heat-Shock Response, Photosynthesis
- Abstract
Extreme temperatures are among the most important stressors limiting plant growth and development. Results indicate that light substantially influences the acclimation processes to both low and high temperatures, and it may affect the level of stress injury. The interaction between light and temperature in the regulation of stress acclimation mechanisms is complex, and both light intensity and spectral composition play an important role. Higher light intensities may lead to overexcitation of the photosynthetic electron transport chain; while different wavelengths may act through different photoreceptors. These may induce various stress signalling processes, leading to regulation of stomatal movement, antioxidant and osmoregulation capacities, hormonal actions, and other stress-related pathways. In recent years, we have significantly expanded our knowledge in both light and temperature sensing and signalling. The present review provides a synthesis of results for understanding how light influences the acclimation of plants to extreme low or high temperatures, including the sensing mechanisms and molecular crosstalk processes.
- Published
- 2021
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32. Acclimation of photosynthetic processes and metabolic responses to elevated temperatures in cereals.
- Author
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Janda T, Tajti J, Hamow KÁ, Marček T, Ivanovska B, Szalai G, Pál M, Zalewska ED, and Darkó É
- Subjects
- Chlorophyll A, Photosynthesis, Temperature, Acclimatization, Edible Grain
- Abstract
The aim of the present work was to better understand the molecular mechanisms of heat acclimation processes in cereals. A large number of winter and spring wheat, barley and oat varieties were grown under either control conditions (22/20°C) or under a mild heat stress (30°C) that induce the acclimation processes. The temperature dependence of chlorophyll a fluorescence induction and gas exchange parameters showed that heat acclimation increased the thermotolerance of the photosynthetic apparatus, but these changes did not differ sharply in the winter-spring type cereals. Similarly, to wheat, elevated temperature also led to increasing transpiration rate and reduced water use efficiency in barley and oat plants. A non-targeted metabolomic analysis focusing on polar metabolites in two selected barley (winter type Mv Initium and spring type Conchita) and in two oat varieties (winter type Mv Hópehely and spring type Mv Pehely) revealed substantial differences between both the two species and between the acclimated and non-acclimated plants. Several compounds, including sugars, organic acids, amino acids and alcohols could be separated and detected. The expression level of the CYP707, HSP90, galactinol synthase, raffinose synthase and α-galactosidase genes showed genotype-dependent changes after 1 day; however, the CYP707 was the only one, which was still upregulated in at least some of the genotypes. Results suggest that heat acclimation itself does not require general induction of primary metabolites. However, induction of specific routes, e.g. the induction of the raffinose family oligosaccharides, especially the synthesis of galactinol, may also contribute the improved heat tolerance in cereals., (© 2020 Scandinavian Plant Physiology Society.)
- Published
- 2021
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33. Editorial: Aegilops : Promising Genesources to Improve Agronomical and Quality Traits of Wheat.
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Rakszegi M, Molnár I, Darkó É, Tiwari VK, and Shewry P
- Published
- 2020
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34. Light intensity and spectrum affect metabolism of glutathione and amino acids at transcriptional level.
- Author
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Toldi D, Gyugos M, Darkó É, Szalai G, Gulyás Z, Gierczik K, Székely A, Boldizsár Á, Galiba G, Müller M, Simon-Sarkadi L, and Kocsy G
- Subjects
- Amino Acids genetics, Glutathione genetics, Triticum genetics, Amino Acids metabolism, Glutathione metabolism, Light, Photosynthesis, Triticum metabolism
- Abstract
The effects of various light intensities and spectral compositions on glutathione and amino acid metabolism were compared in wheat. Increase of light intensity (low-normal-high) was accompanied by a simultaneous increase in the shoot fresh weight, photosynthetic activity and glutathione content. These parameters were also affected by the modification of the ratios of blue, red and far-red components (referred to as blue, pink and far-red lights) compared to normal white light. The photosynthetic activity and the glutathione content decreased to 50% and the percentage of glutathione disulfide (characterising the redox state of the tissues) in the total glutathione pool doubled in far-red light. The alterations in the level and redox state of the antioxidant glutathione resulted from the effect of light on its synthesis as it could be concluded from the changes in the transcription of the related genes. Modification of the light conditions also greatly affected both the amount and the ratio of free amino acids. The total free amino acid content was greatly induced by the increase of light intensity and was greatly reduced in pink light compared to the normal intensity white light. The concentrations of most amino acids were similarly affected by the light conditions as described for the total free amino acid content but Pro, Met, Thr, ornithine and cystathionine showed unique response to light. As observed for the amino acid levels, the expression of several genes involved in their metabolism also enhanced due to increased light intensity. Interestingly, the modification of the spectrum greatly inhibited the expression of most of these genes. Correlation analysis of the investigated parameters indicates that changes in the light conditions may affect growth through the adjustment of photosynthesis and the glutathione-dependent redox state of the tissues. This process modifies the metabolism of glutathione and amino acids at transcriptional level., Competing Interests: The authors have declared that no competing interests exist.
- Published
- 2019
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35. miR824/AGAMOUS-LIKE16 Module Integrates Recurring Environmental Heat Stress Changes to Fine-Tune Poststress Development.
- Author
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Szaker HM, Darkó É, Medzihradszky A, Janda T, Liu HC, Charng YY, and Csorba T
- Abstract
Plant development is continually fine-tuned based on environmental factors. How environmental perturbations are integrated into the developmental programs and how poststress adaptation is regulated remains an important topic to dissect. Vegetative to reproductive phase change is a very important developmental transition that is complexly regulated based on endogenous and exogenous cues. Proper timing of flowering is vital for reproductive success. It has been shown previously that AGAMOUS LIKE 16 (AGL16), a MADS-box transcription factor negatively regulates flowering time transition through FLOWERING LOCUS T (FT), a central downstream floral integrator. AGL16 itself is negatively regulated by the microRNA miR824. Here we present a comprehensive molecular analysis of miR824/AGL16 module changes in response to mild and recurring heat stress. We show that miR824 accumulates gradually in response to heat due to the combination of transient transcriptional induction and posttranscriptional stability. miR824 induction requires heat shock cis -elements and activity of the HSFA1 family and HSFA2 transcription factors. Parallel to miR824 induction, its target AGL16 is decreased, implying direct causality. AGL16 posttranscriptional repression during heat stress, however, is more complex, comprising of a miRNA-independent, and a miR824-dependent pathway. We also show that AGL16 expression is leaf vein-specific and overlaps with miR824 (and FT) expression. AGL16 downregulation in response to heat leads to a mild derepression of FT . Finally, we present evidence showing that heat stress regulation of miR824/AGL16 is conserved within Brassicaceae . In conclusion, due to the enhanced post-transcriptional stability of miR824, stable repression of AGL16 is achieved following heat stress. This may serve to fine-tune FT levels and alter flowering time transition. Stress-induced miR824, therefore, can act as a "posttranscriptional memory factor" to extend the acute impact of environmental fluctuations in the poststress period., (Copyright © 2019 Szaker, Darkó, Medzihradszky, Janda, Liu, Charng and Csorba.)
- Published
- 2019
- Full Text
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36. Unlocking the Genetic Diversity and Population Structure of a Wild Gene Source of Wheat, Aegilops biuncialis Vis. , and Its Relationship With the Heading Time.
- Author
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Ivanizs L, Monostori I, Farkas A, Megyeri M, Mikó P, Türkösi E, Gaál E, Lenykó-Thegze A, Szőke-Pázsi K, Szakács É, Darkó É, Kiss T, Kilian A, and Molnár I
- Abstract
Understanding the genetic diversity of Aegilops biuncialis , a valuable source of agronomical useful genes, may significantly facilitate the introgression breeding of wheat. The genetic diversity and population structure of 86 Ae. biuncialis genotypes were investigated by 32700 DArT markers with the simultaneous application of three statistical methods- neighbor-joining clustering, Principal Coordinate Analysis, and the Bayesian approach to classification. The collection of Ae. biuncialis accessions was divided into five groups that correlated well with their eco-geographic habitat: A (North Africa), B (mainly from Balkans), C (Kosovo and Near East), D (Turkey, Crimea, and Peloponnese), and E (Azerbaijan and the Levant region). The diversity between the Ae. biuncialis accessions for a phenological trait (heading time), which is of decisive importance in the adaptation of plants to different eco-geographical environments, was studied over 3 years. A comparison of the intraspecific variation in the heading time trait by means of analysis of variance and principal component analysis revealed four phenotypic categories showing association with the genetic structure and geographic distribution, except for minor differences. The detailed exploration of genetic and phenologic divergence provides an insight into the adaptation capacity of Ae. biuncialis , identifying promising genotypes that could be utilized for wheat improvement., (Copyright © 2019 Ivanizs, Monostori, Farkas, Megyeri, Mikó, Türkösi, Gaál, Lenykó-Thegze, Szőke-Pázsi, Szakács, Darkó, Kiss, Kilian and Molnár.)
- Published
- 2019
- Full Text
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37. Drought stress affects the protein and dietary fiber content of wholemeal wheat flour in wheat/Aegilops addition lines.
- Author
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Rakszegi M, Darkó É, Lovegrove A, Molnár I, Láng L, Bedő Z, Molnár-Láng M, and Shewry P
- Subjects
- Aegilops growth & development, Dehydration, Aegilops genetics, Crosses, Genetic, Dietary Fiber metabolism, Flour, Plant Proteins, Dietary biosynthesis, Plant Proteins, Dietary genetics, Triticum genetics, Triticum growth & development
- Abstract
Wild relatives of wheat, such as Aegilops spp. are potential sources of genes conferring tolerance to drought stress. As drought stress affects seed composition, the main goal of the present study was to determine the effects of drought stress on the content and composition of the grain storage protein (gliadin (Gli), glutenin (Glu), unextractable polymeric proteins (UPP%) and dietary fiber (arabinoxylan, β-glucan) components of hexaploid bread wheat (T. aestivum) lines containing added chromosomes from Ae. biuncialis or Ae. geniculata. Both Aegilops parents have higher contents of protein and β-glucan and higher proportions of water-soluble arabinoxylans (determined as pentosans) than wheat when grown under both well-watered and drought stress conditions. In general, drought stress resulted in increased contents of protein and total pentosans in the addition lines, while the β-glucan content decreased in many of the addition lines. The differences found between the wheat/Aegilops addition lines and wheat parents under well-watered conditions were also manifested under drought stress conditions: Namely, elevated β-glucan content was found in addition lines containing chromosomes 5Ug, 7Ug and 7Mb, while chromosomes 1Ub and 1Mg affected the proportion of polymeric proteins (determined as Glu/Gli and UPP%, respectively) under both well-watered and drought stress conditions. Furthermore, the addition of chromosome 6Mg decreased the WE-pentosan content under both conditions. The grain composition of the Aegilops accessions was more stable under drought stress than that of wheat, and wheat lines with the added Aegilops chromosomes 2Mg and 5Mg also had more stable grain protein and pentosan contents. The negative effects of drought stress on both the physical and compositional properties of wheat were also reduced by the addition of these. These results suggest that the stability of the grain composition could be improved under drought stress conditions by the intraspecific hybridization of wheat with its wild relatives., Competing Interests: The authors have declared that no competing interests exist.
- Published
- 2019
- Full Text
- View/download PDF
38. Addition of Aegilops U and M Chromosomes Affects Protein and Dietary Fiber Content of Wholemeal Wheat Flour.
- Author
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Rakszegi M, Molnár I, Lovegrove A, Darkó É, Farkas A, Láng L, Bedő Z, Doležel J, Molnár-Láng M, and Shewry P
- Abstract
Cereal grain fiber is an important health-promoting component in the human diet. One option to improve dietary fiber content and composition in wheat is to introduce genes from its wild relatives Aegilops biuncialis and Aegilops geniculata . This study showed that the addition of chromosomes 2U
g , 4Ug , 5Ug , 7Ug , 2Mg , 5Mg , and 7Mg of Ae. geniculata and 3Ub , 2Mb , 3Mb , and 7Mb of Ae. biuncialis into bread wheat increased the seed protein content. Chromosomes 1Ug and 1Mg increased the proportion of polymeric glutenin proteins, while the addition of chromosomes 1Ub and 6Ub led to its decrease. Both Aegilops species had higher proportions of β-glucan compared to arabinoxylan (AX) than wheat lines, and elevated β-glucan content was also observed in wheat chromosome addition lines 5U, 7U, and 7M. The AX content in wheat was increased by the addition of chromosomes 5Ug , 7Ug , and 1Ub while water-soluble AX was increased by the addition of chromosomes 5U, 5M, and 7M, and to a lesser extent by chromosomes 3, 4, 6Ug , and 2Mb . Chromosomes 5Ug and 7Mb also affected the structure of wheat AX, as shown by the pattern of oligosaccharides released by digestion with endoxylanase. These results will help to map genomic regions responsible for edible fiber content in Aegilops and will contribute to the efficient transfer of wild alleles in introgression breeding programs to obtain wheat varieties with improved health benefits. Key Message: Addition of Aegilops U- and M-genome chromosomes 5 and 7 improves seed protein and fiber content and composition in wheat.- Published
- 2017
- Full Text
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39. Comparative analysis of polyamine metabolism in wheat and maize plants.
- Author
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Szalai G, Janda K, Darkó É, Janda T, Peeva V, and Pál M
- Subjects
- Biomass, Chlorophyll metabolism, Chlorophyll A, Fluorescence, Gases metabolism, Lipid Peroxidation drug effects, Models, Biological, Osmotic Pressure drug effects, Phenylalanine Ammonia-Lyase metabolism, Plant Leaves drug effects, Plant Leaves metabolism, Polyamines pharmacology, Polyethylene Glycols pharmacology, Proline metabolism, Putrescine metabolism, Putrescine pharmacology, Salicylic Acid metabolism, Spermidine metabolism, Spermidine pharmacology, Spermine metabolism, Spermine pharmacology, Triticum drug effects, Zea mays drug effects, Polyamines metabolism, Triticum metabolism, Zea mays metabolism
- Abstract
In the present work changes in polyamine contents were investigated after various hydroponic polyamine treatments (putrescine, spermidine and spermine at 0.1, 0.3 and 0.5 mM concentrations) in two different crop species, wheat and maize. In contrast to putrescine, higher polyamines (spermidine and spermine) induced concentration-dependent oxidative damage in both crops, resulting in decreased biomass. The unfavourable effects of polyamines were more pronounced in the roots, and maize was more sensitive than wheat. The adverse effects of polyamine treatment were proportional to the accumulation of polyamine and the plant hormone salicylic acid in the leaves and roots of both plant species. Changes in polyamine content and catabolism during osmotic stress conditions were also studied after beneficial pre-treatment with putrescine. The greater positive effect of putrescine in wheat than in maize can be explained by differences in the polyamine metabolism under normal and osmotic stress conditions, and by relationship between polyamines and salicylic acid. The results demonstrated that changes in the polyamine pool are important for fine tuning of polyamine signalling, which influences the hormonal balance required if putrescine is to exert a protective effect under stress conditions., (Copyright © 2017 Elsevier Masson SAS. All rights reserved.)
- Published
- 2017
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40. Dissecting the U, M, S and C genomes of wild relatives of bread wheat (Aegilops spp.) into chromosomes and exploring their synteny with wheat.
- Author
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Molnár I, Vrána J, Burešová V, Cápal P, Farkas A, Darkó É, Cseh A, Kubaláková M, Molnár-Láng M, and Doležel J
- Subjects
- Flow Cytometry, In Situ Hybridization, Chromosomes, Plant genetics, Triticum genetics
- Abstract
Goat grasses (Aegilops spp.) contributed to the evolution of bread wheat and are important sources of genes and alleles for modern wheat improvement. However, their use in alien introgression breeding is hindered by poor knowledge of their genome structure and a lack of molecular tools. The analysis of large and complex genomes may be simplified by dissecting them into single chromosomes via flow cytometric sorting. In some species this is not possible due to similarities in relative DNA content among chromosomes within a karyotype. This work describes the distribution of GAA and ACG microsatellite repeats on chromosomes of the U, M, S and C genomes of Aegilops, and the use of microsatellite probes to label the chromosomes in suspension by fluorescence in situ hybridization (FISHIS). Bivariate flow cytometric analysis of chromosome DAPI fluorescence and fluorescence of FITC-labelled microsatellites made it possible to discriminate all chromosomes and sort them with negligible contamination by other chromosomes. DNA of purified chromosomes was used as a template for polymerase chain reation (PCR) using Conserved Orthologous Set (COS) markers with known positions on wheat A, B and D genomes. Wheat-Aegilops macrosyntenic comparisons using COS markers revealed significant rearrangements in the U and C genomes, while the M and S genomes exhibited structure similar to wheat. Purified chromosome fractions provided an attractive resource to investigate the structure and evolution of the Aegilops genomes, and the COS markers assigned to Aegilops chromosomes will facilitate alien gene introgression into wheat., (© 2016 The Authors The Plant Journal © 2016 John Wiley & Sons Ltd.)
- Published
- 2016
- Full Text
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41. Salicylic Acid and Sodium Salicylate Alleviate Cadmium Toxicity to Different Extents in Maize (Zea mays L.).
- Author
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Gondor OK, Pál M, Darkó É, Janda T, and Szalai G
- Subjects
- Aminoacyltransferases metabolism, Antioxidants metabolism, Ascorbic Acid metabolism, Catalase metabolism, Chlorophyll analysis, Glutathione Reductase metabolism, Glutathione Transferase metabolism, Malondialdehyde analysis, Oxidative Stress, Peroxidases metabolism, Phytochelatins metabolism, Plant Leaves chemistry, Plant Leaves drug effects, Plant Leaves metabolism, Plant Roots chemistry, Plant Roots drug effects, Plant Roots metabolism, Seedlings drug effects, Spectrometry, Fluorescence, Sulfhydryl Compounds analysis, Zea mays metabolism, Cadmium toxicity, Salicylic Acid pharmacology, Sodium Salicylate pharmacology, Zea mays drug effects
- Abstract
The role of salicylic acid in Cd tolerance has attracted more attention recently but no information is available on the efficiency of different forms of salicylic acid. The aim was thus to investigate whether both the acid and salt forms of salicylic acid provide protection against Cd stress and to compare their mode of action. Young maize plants were grown under controlled environmental conditions. One group of 10-day-old seedlings were treated with 0.5 mM SA or NaSA for 1 day then half of the pants were treated with 0.5 mM Cd for 1 day. Another group of seedlings was treated with 0.5 mM CdSO4 for 1 day without pre-treatment with SA or NaSA, while a third group was treated simultaneously with Cd and either SA or NaSA. Both salicylic acid forms reduced the Cd accumulation in the roots. Treatment with the acidic form meliorated the Cd accumulation in the leaves, while Na-salicylate increased the phytochelatin level in the roots and the amount of salicylic acid in the leaves. Furthermore, increased antioxidant enzyme activity was mainly induced by the acid form, while glutathione-related redox changes were influenced mostly by the salt form. The acidic and salt forms of salicylic acid affected the two antioxidant systems in different ways, and the influence of these two forms on the distribution and detoxification of Cd also differed. The present results also draw attention to the fact that generalisations about the stress protective mechanisms induced by salicylic acid are misleading since different forms of SA may exert different effects on the plants via separate mechanisms.
- Published
- 2016
- Full Text
- View/download PDF
42. Addition of Manas barley chromosome arms to the hexaploid wheat genome.
- Author
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Türkösi E, Cseh A, Darkó É, and Molnár-Láng M
- Subjects
- Flowers growth & development, Genetic Markers genetics, Microsatellite Repeats genetics, Salts pharmacology, Stress, Physiological drug effects, Stress, Physiological genetics, Chromosomes, Plant genetics, Crosses, Genetic, Genes, Plant genetics, Hordeum genetics, Polyploidy, Triticum growth & development
- Abstract
Background: Cultivated barley belongs to the tertiary genepool of hexaploid wheat. Genes of interest can be transferred from barley into wheat through wide hybridization. The application of wheat-barley introgression lines could provide an excellent tool for the transfer of earliness, favourable amino acid composition, biotic stress resistance, abiotic stress tolerance, or good tillering ability into wheat., Results: A set of 10 wheat-barley ditelosomic addition lines (2HS, 2HL, 3HS, 3HL, 4HS, 4HL, 6HS, 6HL, 7HS and 7HL) was developed from the progenies of an Asakaze/Manas wheat-barley hybrid produced in Martonvásár, Hungary. The addition lines were selected from self-fertilized plants of the BC2F2-BC2F4 generations using genomic in situ hybridization (GISH) and were identified by fluorescence in situ hybridization (FISH) with repetitive DNA probes [HvT01, (GAA)7 and centromere-specific (AGGGAG)4 probes]. The cytogenetic identification was confirmed using barley arm-specific SSR and STS markers. The ditelosomic additions were propagated in the phytotron and in the field, and morphological parameters (plant height, tillering, length of the main spike, number of seeds/spike and seeds/plant, and spike characteristics) were described. In addition, the salt stress response of the ditelosomic additions was determined., Conclusions: The six-rowed winter barley cultivar Manas is much better adapted to Central European environmental conditions than the two-rowed spring barley Betzes previously used in wheat-barley crosses. The production of wheat-barley ditelosomic addition lines has a wide range of applications both for breeding (transfer of useful genes to the recipient species) and for basic research (mapping of barley genes, genetic and evolutionary studies and heterologous expression of barley genes in the wheat background).
- Published
- 2016
- Full Text
- View/download PDF
43. Wheat-Aegilops biuncialis amphiploids have efficient photosynthesis and biomass production during osmotic stress.
- Author
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Dulai S, Molnár I, Szopkó D, Darkó É, Vojtkó A, Sass-Gyarmati A, and Molnár-Láng M
- Subjects
- Droughts, Poaceae genetics, Poaceae metabolism, Triticum genetics, Triticum metabolism, Biomass, Hybridization, Genetic, Osmotic Pressure, Photosynthesis physiology, Poaceae physiology, Polyploidy
- Abstract
Osmotic stress responses of water content, photosynthetic parameters and biomass production were investigated in wheat-Aegilops biuncialis amphiploids and in wheat genotypes to clarify whether they can use to improve the drought tolerance of bread wheat. A decrease in the osmotic pressure of the medium resulted in considerable water loss, stomatal closure and a decreased CO2 assimilation rate for the wheat genotypes, while the changes in these parameters were moderate for the amphiploids. Maximal assimilation rate was maintained at high level even under severe osmotic stress in the amphiploids, while it decreased substantially in the wheat genotypes. Nevertheless, the effective quantum yield of PS II was higher and the quantum yield of non-photochemical quenching of PS II and PS I was lower for the amphiploids than for the wheat cultivars. Parallel with this, higher cyclic electron flow was detected in wheat than in the amphiploids. The elevated photosynthetic activity of amphiploids under osmotic stress conditions was manifested in higher biomass production by roots and shoots as compared to wheat genotypes. These results indicate that the drought-tolerant traits of Ae. biuncialis can be manifested in the wheat genetic background and these amphiploids are suitable genetic materials for improving drought tolerance of wheat., (Copyright © 2013 Elsevier GmbH. All rights reserved.)
- Published
- 2014
- Full Text
- View/download PDF
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