58 results on '"Lütken H"'
Search Results
2. Production of interspecific Campanula hybrids by ovule culture: exploring the effect of ovule isolation time
- Author
-
Röper, A.-C., Lütken, H., Christensen, B., Boutilier, K., Petersen, K. K., and Müller, R.
- Published
- 2015
- Full Text
- View/download PDF
3. Preliminary prospects of northwestern Amazonian shade tolerant species with ornamental potential
- Author
-
Ferreira, A.B., primary, Garcia, L., additional, Ming, L.C., additional, Lütken, H., additional, and Favero, B.T., additional
- Published
- 2020
- Full Text
- View/download PDF
4. New ornamental bedding plants for temperate regions
- Author
-
Lütken, H., primary and Favero, B.T., additional
- Published
- 2020
- Full Text
- View/download PDF
5. Transformation ofKalanchoëand oilseed rape with ORFs 11-15 fromAgrobacterium rhizogenes
- Author
-
Favero, B.T., primary, Hansen, H.B., additional, Rangslang, R.K., additional, Liu, Z., additional, Hegelund, J.N., additional, Müller, R., additional, Kodahl, N., additional, and Lütken, H., additional
- Published
- 2020
- Full Text
- View/download PDF
6. Postharvest quality of novel Campanula lines – assessment of indoor longevity and quality
- Author
-
Hansen, H.B., primary, Favero, B.T., additional, and Lütken, H., additional
- Published
- 2019
- Full Text
- View/download PDF
7. Anthocyanin elicitation for bio-sustainable colourant production in carrot
- Author
-
Barba-Espín, G., primary, Lütken, H., additional, Glied, S., additional, Crocoll, C., additional, Joernsgaard, B., additional, and Müller, R., additional
- Published
- 2019
- Full Text
- View/download PDF
8. An in vitro seed germination protocol forPlukenetia volubilisL.
- Author
-
Kodahl, N., primary, García-Dávila, C.R., additional, Cachique, D., additional, Sørensen, M., additional, and Lütken, H., additional
- Published
- 2018
- Full Text
- View/download PDF
9. Modification of ethylene sensitivity in ornamental plants using CRISPR/Cas9
- Author
-
Kemp, O., primary, Favero, B.T., additional, Hegelund, J.N., additional, Møller, S.R., additional, Müller, R., additional, Petersen, B.L., additional, and Lütken, H., additional
- Published
- 2017
- Full Text
- View/download PDF
10. New developments in GMO science – from gene function to application
- Author
-
Lütken, H., primary, Kodahl, N., additional, and Müller, R., additional
- Published
- 2016
- Full Text
- View/download PDF
11. AGROBACTERIUM RHIZOGENES MEDIATED TRANSFORMATION OF RHODIOLA SP. - AN APPROACH TO ENHANCE THE LEVEL OF BIOACTIVE COMPOUNDS
- Author
-
Himmelboe, M., primary, Lauridsen, U.B., additional, Hegelund, J.N., additional, Müller, R., additional, and Lütken, H., additional
- Published
- 2015
- Full Text
- View/download PDF
12. NATURAL TRANSFORMATION IN PLANT BREEDING - A BIOTECHNOLOGICAL PLATFORM FOR QUALITY IMPROVEMENT OF ORNAMENTAL, AGRICULTURAL AND MEDICINAL PLANTS
- Author
-
Lütken, H., primary, Hegelund, J.N., additional, Himmelboe, M., additional, Lauridsen, U.B., additional, and Müller, R., additional
- Published
- 2015
- Full Text
- View/download PDF
13. PHOTOPERIOD AND COLD NIGHT TEMPERATURE IN CONTROL OF FLOWERING IN KALANCHOË
- Author
-
Lopes Coelho, L., primary, Kuligowska, K., additional, Lütken, H., additional, and Müller, R., additional
- Published
- 2015
- Full Text
- View/download PDF
14. FUTURE PERSPECTIVES OF IN VITRO CULTURE AND PLANT BREEDING
- Author
-
Kuligowska, K., primary, Lütken, H., additional, Hegelund, J.N., additional, and Müller, R., additional
- Published
- 2015
- Full Text
- View/download PDF
15. ETHYLENE RESPONSES IN THREE HYDRANGEA LINES
- Author
-
Lauridsen, U.B., primary, Müller, R., additional, and Lütken, H., additional
- Published
- 2015
- Full Text
- View/download PDF
16. Production of interspecific Campanula hybrids by ovule culture: exploring the effect of ovule isolation time
- Author
-
Röper, A.-C., primary, Lütken, H., additional, Christensen, B., additional, Boutilier, K., additional, Petersen, K. K., additional, and Müller, R., additional
- Published
- 2014
- Full Text
- View/download PDF
17. BREEDING OF HIBISCUS ROSA-SINENSIS FOR GARDEN USE IN DENMARK
- Author
-
Kuligowska, K., primary, Simonsen, M., additional, Lütken, H., additional, Müller, R., additional, and Christensen, B., additional
- Published
- 2013
- Full Text
- View/download PDF
18. EFFECT OF THE ETHYLENE INHIBITOR 1-MCP IN POSTHARVEST CHAINS OF MINI-PHALAENOPSIS
- Author
-
Hansen, M.M., primary, Müller, R., additional, and Lütken, H., additional
- Published
- 2013
- Full Text
- View/download PDF
19. PHENOTYPICAL AND GENOTYPICAL CHARACTERISATION OF COMPACT KALANCHOË LINES PRODUCED BY A NON-GMO TRANSFORMATION STRATEGY
- Author
-
Lütken, H., primary, Jensen, E.B., additional, Wallström, S.V., additional, Müller, R., additional, and Christensen, B., additional
- Published
- 2012
- Full Text
- View/download PDF
20. EXPRESSION LEVELS OF GROWTH REDUCING GENES TRANSFERRED BY AGROBACTERIUM RHIZOGENES USED AS A GENETIC TOOL IN ORNAMENTAL PLANTS
- Author
-
Lütken, H., primary, Jensen, E.B., additional, Müller, R., additional, and Christensen, B., additional
- Published
- 2012
- Full Text
- View/download PDF
21. DEVELOPMENT AND EVALUATION OF A NON-GMO BREEDING TECHNIQUE EXEMPLIFIED BY KALANCHOË
- Author
-
Lütken, H., primary, Jensen, E.B., additional, Wallström, S.V., additional, Müller, R., additional, and Christensen, B., additional
- Published
- 2012
- Full Text
- View/download PDF
22. EFFECT OF DIFFERENT OVULE ISOLATION TIMES ON THE EMBRYO DEVELOPMENT OF CAMPANULA HYBRIDS
- Author
-
Röper, A.-C., primary, Lütken, H., additional, Hegelund, J.N., additional, Petersen, K.K., additional, Christensen, B., additional, and Müller, R., additional
- Published
- 2012
- Full Text
- View/download PDF
23. TRANSFORMATION WITH ROL GENES FROM AGROBACTERIUM RHIZOGENES AS A STRATEGY TO BREED COMPACT ORNAMENTAL PLANTS WITH IMPROVED POSTHARVEST QUALITY
- Author
-
Christensen, B., primary, Sriskandarajah, S., additional, Jensen, E.B., additional, Lütken, H., additional, and Müller, R., additional
- Published
- 2010
- Full Text
- View/download PDF
24. A potential model for isobaric analogue states
- Author
-
Bondorf, J.P., primary, Lütken, H., additional, and Jägare, S., additional
- Published
- 1966
- Full Text
- View/download PDF
25. Elastic scattering of protons at the threshold for the quasi-elastic (p, n) process
- Author
-
Bondorf, J.P., primary, Ellegaard, C., additional, Kantele, J., additional, Lütken, H., additional, and Vedelsby, P., additional
- Published
- 1967
- Full Text
- View/download PDF
26. Elicitation of Flavonoids in Kalanchoe pinnata by Agrobacterium rhizogenes-Mediated Transformation and UV-B Radiation
- Author
-
Renate Müller, Henrik Lütken, Lars Porskjær Christensen, Rime Bahij El-Houri, Amalia Fkiara, Gregorio Barba-Espín, Khasim, S., Long, C., Thammasiri, K., and Lütken, H.
- Subjects
chemistry.chemical_classification ,Antioxidant ,biology ,Agrobacterium ,medicine.medical_treatment ,fungi ,Flavonoid ,food and beverages ,Kalanchoe ,biology.organism_classification ,Elicitor ,Crassulaceae ,Transformation (genetics) ,chemistry ,medicine ,Food science ,Medicinal plants - Abstract
Kalanchoe pinnata from the stonecrop family (Crassulaceae) is a medicinal plant with high content of bioactive compounds. The plant is known for its anti-allergic, antioxidant, anti-inflammatory, antimicrobial and antibacterial activities, which are mainly attributed to flavonoids. Low yields of bioactive compounds in medicinal plants have led to new strategies for enhancing their biosynthetic capacity in order to increase the content of specialized metabolites. Herein, the accumulation of specialized metabolites in plants can be triggered by elicitation methods. In the current study, different elicitation strategies were conducted towards the enhancement of bioactive compounds in K. pinnata leaves. We investigated the effect of natural transformation with the Agrobacterium rhizogenes strain A4 as means of biological elicitation on the total content of flavonoids in the leaves of K. pinnata. Furthermore, the effect of supplemental UV-B radiation, as physical elicitor, was assessed on the total flavonoid content of both wild-type (WT) and rol-transformed plants. The combined effect of the two mentioned elicitation methods was also examined. The data showed that presence of rol genes resulted in an increase of 24% in the total flavonoid content compared to WT plants. The supplemental UV-B radiation increased the total content of flavonoids with 95% and 89% in the WT and the rol+ plants, respectively. Collectively, a synergistic effect was shown as the combination of the two factors dramatically increased (133%) the total flavonoid content in K. pinnata leaves.
- Published
- 2020
27. Superior osmotic stress tolerance in oilseed rape transformed with wild-type Rhizobium rhizogenes.
- Author
-
Chen X, Lütken H, Liang K, Liu F, and Favero BT
- Subjects
- Agrobacterium genetics, Agrobacterium physiology, Plants, Genetically Modified, Gene Expression Regulation, Plant, Polyethylene Glycols pharmacology, Antioxidants metabolism, Osmoregulation genetics, Plant Proteins genetics, Plant Proteins metabolism, Transformation, Genetic, Water metabolism, Osmotic Pressure, Brassica napus genetics, Brassica napus physiology, Brassica napus microbiology, Plant Roots microbiology, Plant Roots genetics, Plant Roots physiology, Plant Leaves genetics, Plant Leaves physiology
- Abstract
Key Message: Natural transformation with R. rhizogenes enhances osmotic stress tolerance in oilseed rape through increasing osmoregulation capacity, enhancing maintenance of hydraulic integrity and total antioxidant capacity. Transformation of plants using wild strains of agrobacteria is termed natural transformation and is not covered by GMO legislation in, e.g., European Union and Japan. In this study, offspring lines of Rhizobium rhizogenes naturally transformed oilseed rape (Brassica napus), i.e., A11 and B3 (termed root-inducing (Ri) lines), were investigated for osmotic stress resilience. Under polyethylene glycol 6000 (PEG) 10% (w/v)-induced osmotic stress, the Ri lines, particularly A11, had less severe leaf wilting, higher stomatal conductance (8.2 times more than WT), and a stable leaf transpiration rate (about 2.9 mmol m
-2 s-1 ). Although the leaf relative water content and leaf water potential responded similarly to PEG treatment between the Ri lines and WT, a significant reduction of the turgid weight to dry weight ratio in A11 and B3 indicated a greater capacity of osmoregulation in the Ri lines. Moreover, the upregulation of plasma membrane intrinsic proteins genes (PIPs) in roots and downregulation of these genes in leaves of the Ri lines implied a better maintenance of hydraulic integrity in relation to the WT. Furthermore, the Ri lines had greater total antioxidant capacity (TAC) than the WT under PEG stress. Collectively, the enhanced tolerance of the Ri lines to PEG-induced osmotic stress could be attributed to the greater osmoregulation capacity, better maintenance of hydraulic integrity, and greater TAC than the WT. In addition, Ri-genes (particularly rolA and rolD) play roles in response to osmotic stress in Ri oilseed rape. This study reveals the potential of R. rhizogenes transformation for application in plant drought resilience., (© 2024. The Author(s).)- Published
- 2024
- Full Text
- View/download PDF
28. Enhanced root system architecture in oilseed rape transformed with Rhizobium rhizogenes.
- Author
-
Chen X, Favero BT, Liu F, and Lütken H
- Subjects
- Agrobacterium physiology, Agrobacterium genetics, Plants, Genetically Modified genetics, Droughts, Plant Leaves anatomy & histology, Plant Leaves physiology, Plant Leaves microbiology, Plant Leaves genetics, Transformation, Genetic, Brassica napus genetics, Brassica napus microbiology, Brassica napus physiology, Brassica napus anatomy & histology, Plant Roots microbiology, Plant Roots anatomy & histology, Plant Roots physiology, Plant Roots genetics
- Abstract
Transformation of plants using wild strains of agrobacteria is termed natural transformation and is not covered by GMO legislation in e.g. European Union and Japan. In the current study, offspring lines (A11 and B3) of Rhizobium rhizogenes naturally transformed oilseed rape (Brassica napus) were randomly selected to characterize the morphological traits, and analyze the implications of such morphological changes on plant drought resilience. It was found that the introduction of Ri-genes altered the biomass partitioning to above- and under-ground parts of oilseed rape plants. Compared to the wild type (WT), the A11 and B3 lines exhibited 1.2-4.0 folds lower leaf and stem dry weight, leaf area and plant height, but had 1.3-5.8 folds greater root dry weight, root length and root surface area, resulting in a significantly enhanced root: shoot dry mass ratio and root surface area: leaf area ratio. In addition, the introduction of Ri-genes conferred reduced stomatal pore aperture and increased stomatal density in the B3 line, and increased leaf thickness in A11 line, which could benefit plant drought resilience. Finally, the modulations in morphological traits as a consequence of transformation with Ri-genes are discussed concerning resilience in water-limited conditions. These findings reveal the potential of natural transformation with R. rhizogenes for drought-targeted breeding in crops., Competing Interests: Declaration of Competing Interest No conflict of interest declared, (Copyright © 2024 Elsevier B.V. All rights reserved.)
- Published
- 2024
- Full Text
- View/download PDF
29. Lessons learned from metabolic engineering in hairy roots: Transcriptome and metabolic profile changes caused by Rhizobium-mediated plant transformation in Cucurbitaceae species.
- Author
-
Almeida A, Favero BT, Dong L, Cárdenas PD, Saenz-Mata J, Lütken H, and Bak S
- Subjects
- Cucurbitacins metabolism, Transcriptome genetics, Metabolic Engineering, Transcription Factors genetics, Transcription Factors metabolism, Plant Roots genetics, Plant Roots metabolism, Metabolome, Rhizobium genetics, Cucurbitaceae genetics, Cucurbitaceae metabolism
- Abstract
Cucurbitaceae species are used in traditional medicine around the world. Cucurbitacins are highly oxygenated triterpenoids found in Cucurbitaceae species and exhibit potent anticancer activity alone and in combination with other existing chemotherapeutic drugs. Therefore, increasing production of these specialized metabolites is of great relevance. We recently showed that hairy roots of Cucurbita pepo can be used as a platform for metabolic engineering of cucurbitacins to modify their structure and increase their production. To study the changes in cucurbitacin accumulation upon formation of hairy roots, an empty vector (EV) control and Cucurbitacin inducing bHLH transcription factor 1 (CpCUCbH1)-overexpressing hairy roots of C. pepo were compared to untransformed (WT) roots. Whilst CpCUCbH1-overexpression increased production of cucurbitacins I and B by 5-fold, and cucurbitacin E by 3-fold when compared to EV lines, this increase was not significantly different when compared to WT roots. This indicated that Rhizobium rhizogenes transformation lowered the cucurbitacins levels in hairy roots, but that increasing expression of cucurbitacin biosynthetic genes by CpCUCbH1-overexpression restored cucurbitacin production to WT levels. Subsequent metabolomic and RNA-seq analysis indicated that the metabolic profile and transcriptome of hairy roots was significantly changed when compared to WT roots. Interestingly, it was observed that 11% of the differentially expressed genes were transcription factors. It was noteworthy that the majority of transcripts showing highest Pearson correlation coefficients to the Rhizobium rhizogenes genes rolB, rolC and ORF13a, were predicted to be transcription factors. In summary, hairy roots are an excellent platform for metabolic engineering of plant specialized metabolites, but these extensive transcriptome and metabolic profile changes should be considered in subsequent studies., Competing Interests: Declaration of competing interest The authors acknowledge that this study received funding from the Novo Nordisk Foundation. The funder was not involved in the experimental design, in the collection and interpretation of data, the writing of this article, or the decision to submit it for publication., (Copyright © 2023 The Authors. Published by Elsevier Masson SAS.. All rights reserved.)
- Published
- 2023
- Full Text
- View/download PDF
30. Alternative Rooting Methods for Medicinal Cannabis Cultivation in Denmark-Preliminary Results.
- Author
-
Favero BT, Salomonsen JK, and Lütken H
- Abstract
Cannabis sativa L. is typically propagated through micropropagation or vegetative cuttings, but the use of root-inducing hormones, such as indole-3-butyric acid (IBA), is not allowed for growing medicinal cannabis in Denmark. This study examined alternative rooting treatments, including Rhizobium rhizogenes inoculation, water-only as well as IBA treatments, in eight cannabis cultivars. PCR on root tissue suggested that 19% of R. rhizogenes- inoculated cuttings were transformed. These were derived from "Herijuana", "Wild Thailand", "Motherlode Kush", and "Bruce Banner", indicating a variation in cultivar susceptibility toward R. rhizogenes . A 100% rooting success was achieved regardless of cultivar and treatment, suggesting that alternative rooting agents are not required for efficient vegetative propagation. However, rooted cuttings differed in shoot morphology with improved shoot growth in cuttings treated with R. rhizogenes (195 ± 7 mm) or water (185 ± 7 mm) while inhibited shoot growth under IBA treatment (123 ± 6 mm). This could have advantageous economic implications should cuttings not treated with hormone reach maturity faster than those exposed to the hormone, thereby contributing to completing a full growing cycle more effectively. IBA exposure increased root length, root dry weight, and root/shoot dry weight ratio compared to cuttings treated with R. rhizogenes or water but simultaneously inhibited shoot growth compared to these.
- Published
- 2023
- Full Text
- View/download PDF
31. Kalanchoë blossfeldiana naturally transformed with Rhizobium rhizogenes exhibits superior root phenotype.
- Author
-
Favero BT, Tan Y, Chen X, Müller R, and Lütken H
- Subjects
- Agrobacterium, Phenotype, Plant Roots genetics, Plants, Genetically Modified genetics, Transformation, Genetic, Kalanchoe genetics, Rhizobium
- Abstract
Plant transformation with root oncogenic loci (rol) genes and open reading frames (ORFs) from Rhizobium rhizogenes have not yet targeted the underground root phenotype of these transformants. Hence, there is a need to develop plants with more efficient root system architecture (RSA). Here, RSA was assessed in naturally transformed (NT) and single rol/ORF Kalanchoë blossfeldiana 'Molly' lines in an aeroponic growth system combined with gene expression analysis. Three NT lines; 306, 324 and 331; exhibited better-developed RSA with longer roots and increased root biomass. In line 306, longest root was 6.3 ± 0.3 cm while WT had 4.8 ± 0.1 cm. However, root length of all overexpressing lines was ca. 30% shorter than WT. Root fresh weight of NT lines was 4.5-fold higher than WT. The expression of rolB, ∆ORF13a and ORF14 in the leaves of overexpressing lines was many folds higher than in NT lines. Increased expression of ∆ORF13a and ORF14 in leaves and roots may contribute more to a stronger compact phenotype than previously assumed. The moderate compact phenotype of NT lines combined with improved RSA compared to the overexpressing lines and WT strongly indicate that the use of R. rhizogenes has great potential to produce Kalanchoë phenotypes with enhanced RSA., (Copyright © 2022 The Authors. Published by Elsevier B.V. All rights reserved.)
- Published
- 2022
- Full Text
- View/download PDF
32. Lipid composition of the Amazonian 'Mountain Sacha Inchis' including Plukenetia carolis-vegae Bussmann, Paniagua & C.Téllez.
- Author
-
Kodahl N, Frandsen HB, Lütken H, Petersen IL, Paredes Andrade NJ, García-Davila C, and Sørensen M
- Subjects
- Fatty Acids, Fatty Acids, Unsaturated, Plant Oils, Seeds, Euphorbiaceae, alpha-Linolenic Acid
- Abstract
Several Amazonian species of Plukenetia are remarkably rich sources of polyunsaturated fatty acids, in particular α-linolenic acid. The lipid composition of the large-seeded, recently described 'Mountain Sacha Inchi' Plukenetia carolis-vegae is reported here for the first time, and compared with Plukenetia huayllabambana, two cultivars of Plukenetia volubilis, and a newly developed hybrid between P. volubilis and P. carolis-vegae. All species and cultivars had a very high content of polyunsaturated fatty acids, 82.6-86.7% of total fatty acids, and at least 46.6% α-linolenic acid of total fatty acids. The highest content was found in P. carolis-vegae which had 57.4%. The exceptionally high α-linolenic acid content suggests that P. carolis-vegae may be an important plant-derived dietary source of this essential fatty acid and that the species has considerable potential for further domestication and commercialisation of its seeds and seed oil. A TAG analysis was carried out for the two P. volubilis cultivars, in which LLnLn and LnLL were most prevalent, and for P. huayllabambana, in which LLnLn constituted the largest fraction, followed by LnLnLn, indicating that this large-seeded species also has interesting dietary properties., (© 2022. The Author(s).)
- Published
- 2022
- Full Text
- View/download PDF
33. Transgenic Kalanchoë blossfeldiana , Containing Individual rol Genes and Open Reading Frames Under 35S Promoter, Exhibit Compact Habit, Reduced Plant Growth, and Altered Ethylene Tolerance in Flowers.
- Author
-
Favero BT, Tan Y, Lin Y, Hansen HB, Shadmani N, Xu J, He J, Müller R, Almeida A, and Lütken H
- Abstract
Reduced growth habit is a desirable trait for ornamental potted plants and can successfully be obtained through Rhizobium rhizogenes transformation in a stable and heritable manner. Additionally, it can also be obtained by transformation with Agrobacterium tumefaciens harboring specific genes from R. rhizogenes . The bacterial T-DNA harbors four root oncogenic loci ( rol ) genes and 14 less known open reading frames (ORFs). The four rol genes, i.e., rol A, rol B, rol C, and rol D, are conceived as the common denominator for the compact phenotype and the other less characterized ORFs seem auxiliary but present a potential breeding target for less aberrant and/or more tailored phenotypes. In this study, Kalanchoë blossfeldiana 'Molly' was transformed with individual rol genes and selected ORFs in 35S overexpressing cassettes to comprehensively characterize growth traits, gene copy and expression, and ethylene tolerance of the flowers. An association of reduced growth habit, e.g. height and diameter, was observed for rol B2 and ORF14-2 when a transgene single copy and high gene expression were detected. Chlorophyll content was reduced in overexpressing lines compared to wild type (WT), except for one ΔORF13a (a truncated ORF13a, where SPXX DNA-binding motif is absent). The flower number severely decreased in the overexpressing lines compared to WT. The anthesis timing showed that WT opened the first flower at 68.9 ± 0.9 days and the overexpressing lines showed similar or up to 24 days delay in flowering. In general, a single or low relative gene copy insertion was correlated to higher gene expression, ca. 3 to 5-fold, in rol B and ΔORF13a lines, while in ORF14 such relation was not directly linked. The increased gene expression observed in rol B2 and ΔORF13a-2 contributed to reducing plant growth and a more compact habit. Tolerance of detached flowers to 0.5 μl L
-1 ethylene was markedly higher for ORF14 with 66% less flower closure at day 3 compared to WT. The subcellular localization of rol C and ΔORF13a was investigated by transient expression in Nicotiana benthamiana and confocal images showed that rol C and ΔORF13a are soluble and localize in the cytoplasm being able to enter the nucleus., 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., (Copyright © 2021 Favero, Tan, Lin, Hansen, Shadmani, Xu, He, Müller, Almeida and Lütken.)- Published
- 2021
- Full Text
- View/download PDF
34. Ethephon-induced changes in antioxidants and phenolic compounds in anthocyanin-producing black carrot hairy root cultures.
- Author
-
Barba-Espín G, Chen ST, Agnolet S, Hegelund JN, Stanstrup J, Christensen JH, Müller R, and Lütken H
- Subjects
- Agrobacterium, Antioxidants, Organophosphorus Compounds, Plant Roots, Anthocyanins, Daucus carota
- Abstract
Hairy root (HR) cultures are quickly evolving as a fundamental research tool and as a bio-based production system for secondary metabolites. In this study, an efficient protocol for establishment and elicitation of anthocyanin-producing HR cultures from black carrot was established. Taproot and hypocotyl explants of four carrot cultivars were transformed using wild-type Rhizobium rhizogenes. HR growth performance on plates was monitored to identify three fast-growing HR lines, two originating from root explants (lines NB-R and 43-R) and one from a hypocotyl explant (line 43-H). The HR biomass accumulated 25- to 30-fold in liquid media over a 4 week period. Nine anthocyanins and 24 hydroxycinnamic acid derivatives were identified and monitored using UPLC-PDA-TOF during HR growth. Adding ethephon, an ethylene-releasing compound, to the HR culture substantially increased the anthocyanin content by up to 82% in line 43-R and hydroxycinnamic acid concentrations by >20% in line NB-R. Moreover, the activities of superoxide dismutase and glutathione S-transferase increased in the HRs in response to ethephon, which could be related to the functionality and compartmentalization of anthocyanins. These findings present black carrot HR cultures as a platform for the in vitro production of anthocyanins and antioxidants, and provide new insight into the regulation of secondary metabolism in black carrot., (© The Author(s) 2020. Published by Oxford University Press on behalf of the Society for Experimental Biology. All rights reserved. For permissions, please email: journals.permissions@oup.com.)
- Published
- 2020
- Full Text
- View/download PDF
35. Rhizogenic agrobacteria as an innovative tool for plant breeding: current achievements and limitations.
- Author
-
Desmet S, Dhooghe E, De Keyser E, Van Huylenbroeck J, Müller R, Geelen D, and Lütken H
- Subjects
- Crops, Agricultural genetics, Crops, Agricultural microbiology, Phenotype, Plant Development, Plant Roots microbiology, Plants microbiology, Rhizobium, Agrobacterium genetics, Plant Breeding legislation & jurisprudence, Plant Breeding methods, Plants genetics
- Abstract
Compact plant growth is an economically important trait for many crops. In practice, compactness is frequently obtained by applying chemical plant growth regulators. In view of sustainable and environmental-friendly plant production, the search for viable alternatives is a priority for breeders. Co-cultivation and natural transformation using rhizogenic agrobacteria result in morphological alterations which together compose the Ri phenotype. This phenotype is known to exhibit a more compact plant habit, besides other features. In this review, we highlight the use of rhizogenic agrobacteria and the Ri phenotype with regard to sustainable plant production and plant breeding. An overview of described Ri lines and current breeding applications is presented. The potential of Ri lines as pre-breeding material is discussed from both a practical and legal point of view.
- Published
- 2020
- Full Text
- View/download PDF
36. Preharvest application of ethephon and postharvest UV-B radiation improve quality traits of beetroot (Beta vulgaris L. ssp. vulgaris) as source of colourant.
- Author
-
Barba-Espin G, Glied-Olsen S, Dzhanfezova T, Joernsgaard B, Lütken H, and Müller R
- Subjects
- Beta vulgaris anatomy & histology, Beta vulgaris physiology, Betalains metabolism, Crop Production methods, Food Handling methods, Food Quality, Gene Expression drug effects, Organophosphorus Compounds administration & dosage, Phenols metabolism, Beta vulgaris drug effects, Organophosphorus Compounds pharmacology, Plant Growth Regulators pharmacology, Ultraviolet Rays
- Abstract
Background: Betanins have become excellent replacers for artificial red-purple food colourants. Red beet (Beta vulgaris L. spp. vulgaris) known as beetroot, is a rich source of betalains, which major forms are betanin (red to purple) and vulgaxanthin (yellow). Betalains and phenolic compounds are secondary metabolites, accumulation of which is often triggered by elicitors during plant stress responses. In the present study, pre-harvest applications of ethephon (an ethylene-releasing compound) and postharvest UV-B radiation were tested as elicitors of betalains and phenolic compounds in two beetroot cultivars. Their effects on quality parameters were investigated, and the expression of biosynthetic betalain genes in response to ethephon was determined., Results: Ethephon was applied as foliar spray during the growth of beetroot, resulting in increased betanin (22.5%) and decreased soluble solids contents (9.4%), without detrimental effects on beetroot yield. The most rapid accumulation rate for betanin and soluble solids was observed between 3 and 6 weeks after sowing in both untreated and ethephon-treated beetroots. Overall, the expression of the betalain biosynthetic genes (CYP76AD1, CYP76AD5, CYP76AD6 and DODA1), determining the formation of both betanin and vulgaxanthin, increased in response to ethephon treatment, as did the expression of the betalain pathway activator BvMYB1. In the postharvest environment, the use of short-term UV-B radiation (1.23 kJ m
- 2 ) followed by storages for 3 and 7 days at 15 °C resulted in increased betanin to vulgaxanthin ratio (51%) and phenolic content (15%)., Conclusions: The results of this study provide novel strategies to improve key profitability traits in betalain production. High betanin concentration and high betanin to vulgaxanthin ratio increase the commercial value of the colourant product. In addition, lowering soluble solids levels facilitates higher concentration of beetroot colour during processing. Moreover, we show that enhanced betanin content in ethephon-treated beetroots is linked to increased expression of betalain biosynthetic genes.- Published
- 2018
- Full Text
- View/download PDF
37. Increasing genetic variability in oilseed rape (Brassica napus) - Genotypes and phenotypes of oilseed rape transformed by wild type Agrobacterium rhizogenes.
- Author
-
Hegelund JN, Liang C, Lauridsen UB, Kemp O, Lütken H, and Müller R
- Subjects
- Genes, Bacterial genetics, Genetic Variation, Genotype, Phenotype, Polymerase Chain Reaction, Agrobacterium genetics, Brassica napus genetics, Plants, Genetically Modified genetics
- Abstract
Brassica napus (oilseed rape) is a major oil crop worldwide. Due to the short domestication period of oilseed rape the genetic variability is limited compared to other crops. Transfer of rol and aux genes from Agrobacterium rhizogenes is used in horticulture to increase genetic variability. In the current study, we explore transformation by A. rhizogenes as a biotechnological approach in breeding for more branched and shorter oilseed rape. In the 2nd generation of transformed oilseed rape, branch numbers increased significantly by 49% from 7.7 ± 0.4 to 11.5 ± 1.9 when comparing rol+/aux+ plants with WT. Simultaneously, the apical height of plants was reduced by 25% from 81.3 ± 1.9 cm to 62.4 ± 6.7 cm in rol+/aux+ plants at the onset of flowering. Reproductive parameters affecting yield as seed size and number were negatively affected in rol+/aux+ plants. Interestingly, oil composition was changed in rol+/aux+ seeds. Oleic acid (ω9) contents were reduced by more than 3% whereas α-linolenic acid (ω6) increased by more than 25% in mature seeds. To obtain shorter and more branched breeding material of oilseed rape we suggest crossing plants with the rol+/aux+ genotype back into the parental breeding line. This could reduce the negative impact of rol+/aux+ on yield., (Copyright © 2018 Elsevier B.V. All rights reserved.)
- Published
- 2018
- Full Text
- View/download PDF
38. Anti-biofilm effects of gold and silver nanoparticles synthesized by the Rhodiola rosea rhizome extracts.
- Author
-
Singh P, Pandit S, Beshay M, Mokkapati VRSS, Garnaes J, Olsson ME, Sultan A, Mackevica A, Mateiu RV, Lütken H, Daugaard AE, Baun A, and Mijakovic I
- Subjects
- Biofilms growth & development, Anti-Bacterial Agents chemical synthesis, Anti-Bacterial Agents chemistry, Anti-Bacterial Agents pharmacology, Biofilms drug effects, Gold chemistry, Gold pharmacology, Metal Nanoparticles chemistry, Plant Extracts chemistry, Pseudomonas aeruginosa physiology, Rhizome chemistry, Rhodiola chemistry, Silver chemistry, Silver pharmacology
- Abstract
Bacterial biofilm represents a major problem in medicine. They colonize and damage medical devices and implants and, in many cases, foster development of multidrug-resistant microorganisms. Biofilm development starts by bacterial attachment to the surface and the production of extracellular polymeric substances (EPS). The EPS forms a structural scaffold for dividing bacterial cells. The EPS layers also play a protective role, preventing the access of antibiotics to biofilm-associated microorganisms. The aim of this work was to investigate the production nanoparticles that could be used to inhibit biofilm formation. The applied production procedure from rhizome extracts of Rhodiola rosea is simple and environmentally friendly, as it requires no additional reducing, stabilizing and capping agents. The produced nanoparticles were stable and crystalline in nature with an average diameter of 13-17 nm for gold nanoparticles (AuNPs) and 15-30 nm for silver nanoparticles (AgNPs). Inductively coupled plasma mass spectrometry analysis revealed the concentration of synthesized nanoparticles as 3.3 and 5.3 mg/ml for AuNPs and AgNPs, respectively. Fourier-transform infrared spectroscopy detected the presence of flavonoids, terpenes and phenols on the nanoparticle surface, which could be responsible for reducing the Au and Ag salts to nanoparticles and further stabilizing them. Furthermore, we explored the AgNPs for inhibition of Pseudomonas aeruginosa and Escherichia coli biofilms. AgNPs exhibited minimum inhibitory concentrations of 50 and 100 µg/ml, against P. aeruginosa and E. coli, respectively. The respective minimum bactericidal concentrations were 100 and 200 µg/ml. These results suggest that using the rhizome extracts of the medicinal plant R. rosea represents a viable route for green production of nanoparticles with anti-biofilm effects.
- Published
- 2018
- Full Text
- View/download PDF
39. Foliar-applied ethephon enhances the content of anthocyanin of black carrot roots (Daucus carota ssp. sativus var. atrorubens Alef.).
- Author
-
Barba-Espín G, Glied S, Crocoll C, Dzhanfezova T, Joernsgaard B, Okkels F, Lütken H, and Müller R
- Subjects
- Daucus carota metabolism, Ethylenes metabolism, Plant Roots metabolism, Anthocyanins metabolism, Daucus carota drug effects, Organophosphorus Compounds pharmacology, Plant Roots drug effects
- Abstract
Background: Black carrots (Daucus carota ssp. sativus var. atrorubens Alef.) constitute a valuable source of anthocyanins, which are used as natural red, blue and purple food colourants. Anthocyanins and phenolic compounds are specialised metabolites, accumulation of which often requires elicitors, which act as molecular signals in plant stress responses. In the present study, ethephon, an ethylene-generating compound was explored as enhancer of anthocyanin and phenolic contents during growth of 'Deep Purple' black carrots. The effects of ethephon on several parameters were investigated, and the expression of biosynthetic anthocyanin genes was studied during growth and anthocyanin accumulation., Results: Roots of ethephon-treated carrot plants exhibited an increase in anthocyanin content of approximately 25%, with values ranging from 2.25 to 3.10 mg g
-1 fresh weight, compared with values ranging from 1.50 to 1.90 mg g-1 fresh weight in untreated roots. The most rapid accumulation rate for anthocyanins, phenolic compounds, soluble solids and dry matter was observed between 10 and 13 weeks after sowing in both untreated and ethephon-treated carrots. The differences in anthocyanin contents between untreated and treated carrots increased for several weeks after the ethephon treatment was terminated. Five cyanidin-based anthocyanin forms were identified, with variable relative abundance values detected during root growth. Overall, the expression of the anthocyanin biosynthetic genes analysed (PAL1, PAL3, F3H1, DFR1, LDOX2) increased in response to ethephon treatment, as did the expression of the MYB1 transcription factor, which is associated with activation of the phenylpropanoid pathway under stress conditions. In addition, a correlation was proposed between ethylene and sugar contents and the induction of anthocyanin synthesis., Conclusions: This study presents a novel method for enhancing anthocyanin content in black carrots. This finding is of economic importance as increased pigment concentration per unit of biomass implies improved profitability parameters in food colour production. We provide new insight into the accumulation patterns of the different cyanidin-based anthocyanins and phenolic compounds during root growth. Moreover, we show that enhanced anthocyanin content in ethephon-treated carrots is accompanied by increased expression of anthocyanin biosynthetic genes.- Published
- 2017
- Full Text
- View/download PDF
40. The Agrobacterium rhizogenes oncogenes rolB and ORF13 increase formation of generative shoots and induce dwarfism in Arabidopsis thaliana (L.) Heynh.
- Author
-
Kodahl N, Müller R, and Lütken H
- Subjects
- Arabidopsis physiology, Arabidopsis virology, Bacterial Proteins genetics, Flowers genetics, Flowers physiology, Flowers virology, Genome, Plant, Plant Breeding methods, Plant Shoots genetics, Plant Shoots physiology, Plant Shoots virology, Transformation, Genetic, beta-Glucosidase genetics, Agrobacterium genetics, Arabidopsis genetics, Bacterial Proteins physiology, Open Reading Frames genetics, beta-Glucosidase physiology
- Abstract
Plant transformation with the wild type Ri plasmid T-DNA of Agrobacterium rhizogenes is a promising method for breeding of compact plants and has been the subject of numerous studies. However, knowledge concerning the isolated functions of single genes and ORFs from the plasmid is limited. The rolB and ORF13 oncogenes of A. rhizogenes show considerable promise in plant breeding, but have not been comprehensively studied. Detailed information regarding the morphological impact of specific genes of the Ri plasmid will allow for optimized targeted breeding of plants transformed with the wild type Ri plasmid T-DNA. rolB and ORF13 were recombined into the genome of Arabidopsis thaliana using Gateway
® cloning and the effect on plant growth was assessed biometrically throughout the plants' life cycle. rolB-lines exhibited dwarfing, early necrosis of rosette leaves, altered leaf and flower morphology, and developed an increased number of inflorescences per rosette area compared to the wild type. ORF13-lines were extremely dwarfed, attaining only ca. 1% of the rosette area of the wild type, leaf and flower size was reduced, and the shape modified. The study documents that the traits inferred by the rolB oncogene yield plants with increased formation of generative shoots, but also result in some degree of premature senescence of vegetative organs. The extreme dwarfism seen in ORF13-lines indicate that this oncogene may be more important in the dwarfing response of plants transformed with the wild type Ri plasmid T-DNA than previously assumed and that transformation with this oncogene induces a very compact phenotype., (Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.)- Published
- 2016
- Full Text
- View/download PDF
41. Towards development of new ornamental plants: status and progress in wide hybridization.
- Author
-
Kuligowska K, Lütken H, and Müller R
- Subjects
- Color, Flowers anatomy & histology, Hybrid Vigor genetics, Phenotype, Pigmentation genetics, Plant Leaves anatomy & histology, Plants anatomy & histology, Flowers genetics, Hybridization, Genetic, Plant Breeding methods, Plant Leaves genetics, Plants genetics
- Abstract
Main Conclusion: The present review provides insights into the key findings of the hybridization process, crucial factors affecting the adaptation of new technologies within wide hybridization of ornamental plants and presents perspectives of further development of this strategy. Wide hybridization is one of the oldest breeding techniques that contributed enormously to the development of modern plant cultivars. Within ornamental breeding, it represents the main source of genetic variation. During the long history of wide hybridization, a number of methods were implemented allowing the evolution from a conventional breeding tool into a modern methodology. Nowadays, the research on model plants and crop species increases our understanding of reproductive isolation among distant species and partly explains the background of the traditional approaches previously used for overcoming hybridization barriers. Characterization of parental plants and hybrids is performed using molecular and cytological techniques that strongly facilitate breeding processes. Molecular markers and sequencing technologies are used for the assessment of genetic relationships among plants, as the genetic distance is typically depicted as one of the most important factors influencing cross-compatibility in hybridization processes. Furthermore, molecular marker systems are frequently applied for verification of hybrid state of the progeny. The flow cytometry and genomic in situ hybridization are used in the assessment of hybridization partners and characterization of hybrid progeny in relation to genome stabilization as well as genome recombination and introgression. In the future, new research and technologies are likely to provide more detailed information about genes and pathways responsible for interspecific reproductive isolation. Ultimately, this knowledge will enable development of strategies for obtaining compatible lines for hybrid production. Recent development in sequencing technologies and availability of sequence data will also facilitate creation of new molecular markers that will advance marker-assisted selection in hybridization process.
- Published
- 2016
- Full Text
- View/download PDF
42. A natural frameshift mutation in Campanula EIL2 correlates with ethylene insensitivity in flowers.
- Author
-
Jensen L, Hegelund JN, Olsen A, Lütken H, and Müller R
- Subjects
- Amino Acid Sequence, Base Sequence, Campanulaceae metabolism, Phylogeny, Plant Proteins chemistry, Plant Proteins metabolism, Sequence Alignment, Species Specificity, Transcription Factors chemistry, Transcription Factors metabolism, Campanulaceae genetics, Ethylenes metabolism, Frameshift Mutation, Gene Expression Regulation, Plant, Plant Growth Regulators metabolism, Plant Proteins genetics, Transcription Factors genetics
- Abstract
Background: The phytohormone ethylene plays a central role in development and senescence of climacteric flowers. In ornamental plant production, ethylene sensitive plants are usually protected against negative effects of ethylene by application of chemical inhibitors. In Campanula, flowers are sensitive to even minute concentrations of ethylene., Results: Monitoring flower longevity in three Campanula species revealed C. portenschlagiana (Cp) as ethylene sensitive, C. formanekiana (Cf) with intermediate sensitivity and C. medium (Cm) as ethylene insensitive. We identified key elements in ethylene signal transduction, specifically in Ethylene Response Sensor 2 (ERS2), Constitutive Triple Response 1 (CTR1) and Ethylene Insensitive 3- Like 1 and 2 (EIL1 and EIL2) homologous. Transcripts of ERS2, CTR1 and EIL1 were constitutively expressed in all species both throughout flower development and in response to ethylene. In contrast, EIL2 was found only in Cf and Cm. We identified a natural mutation in Cmeil2 causing a frameshift which resulted in difference in expression levels of EIL2, with more than 100-fold change between Cf and Cm in young flowers., Conclusions: This study shows that the naturally occurring 7 bp frameshift discovered in Cmeil2, a key gene in the ethylene signaling pathway, correlates with ethylene insensitivity in flowers. We suggest that transfer of the eil2 mutation to other plant species will provide a novel tool to engineer ethylene insensitive flowers.
- Published
- 2016
- Full Text
- View/download PDF
43. Interspecific hybridization among cultivars of hardy Hibiscus species section Muenchhusia.
- Author
-
Kuligowska K, Lütken H, Christensen B, and Müller R
- Abstract
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 in temperate regions worldwide. The aim of the study was to investigate hybridization barriers in crosses among cultivars of Hibiscus species from the Muenchhusia section: H. coccineus, H. laevis and H. moscheutos. Crossing barriers were identified as both pre- and post-zygotic. The analysis of pollen tube 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 and flower morphology compared to parental plants. Hybridity state was verified by morphological analysis and RAPD markers. Based on the overall plant morphology, 472 hybrid progenies were obtained.
- Published
- 2016
- Full Text
- View/download PDF
44. Phenotypic and Genotypic Analysis of Newly Obtained Interspecific Hybrids in the Campanula Genus.
- Author
-
Röper AC, Orabi J, Lütken H, Christensen B, Thonning Skou AM, and Müller R
- Subjects
- Amplified Fragment Length Polymorphism Analysis, Breeding, Crosses, Genetic, Genotype, Phenotype, Pollination genetics, Campanulaceae genetics, Flowers genetics, Hybridization, Genetic, Plant Roots genetics
- Abstract
Interspecific hybridisation creates new phenotypes within several ornamental plant species including the Campanula genus. We have employed phenotypic and genotypic methods to analyse and evaluate interspecific hybridisation among cultivars of four Campanula species, i.e. C. cochleariifolia, C. isophylla, C. medium and C. formanekiana. Hybrids were analysed using amplified fragment length polymorphism (AFLP), flow cytometry and biometrical measurements. Results of correlation matrices demonstrated heterogeneous phenotypes for the parental species, which confirmed our basic premise for new phenotypes of interspecific hybrids. AFLP assays confirmed the hybridity and identified self-pollinated plants. Limitation of flow cytometry analysis detection was observed while detecting the hybridity status of two closely related parents, e.g. C. cochleariiafolia × C. isophylla. Phenotypic characteristics such as shoot habitus and flower colour were strongly influenced by one of the parental species in most crosses. Rooting analysis revealed that inferior rooting quality occurred more often in interspecific hybrids than in the parental species. Only interspecific hybrid lines of C. formanekiana 'White' × C. medium 'Pink' showed a high rooting level. Phenotype analyses demonstrated a separation from the interspecific hybrid lines of C. formanekiana 'White' × C. medium 'Pink' to the other clustered hybrids of C. formanekiana and C. medium. In our study we demonstrated that the use of correlation matrices is a suitable tool for identifying suitable cross material. This study presents a comprehensive overview for analysing newly obtained interspecific hybrids. The chosen methods can be used as guidance for analyses for further interspecific hybrids in Campanula, as well as in other ornamental species.
- Published
- 2015
- Full Text
- View/download PDF
45. Ethylene resistance in flowering ornamental plants - improvements and future perspectives.
- Author
-
Olsen A, Lütken H, Hegelund JN, and Müller R
- Abstract
Various strategies of plant breeding have been attempted in order to improve the ethylene resistance of flowering ornamental plants. These approaches span from conventional techniques such as simple cross-pollination to new breeding techniques which modify the plants genetically such as precise genome-editing. The main strategies target the ethylene pathway directly; others focus on changing the ethylene pathway indirectly via pathways that are known to be antagonistic to the ethylene pathway, e.g. increasing cytokinin levels. Many of the known elements of the ethylene pathway have been addressed experimentally with the aim of modulating the overall response of the plant to ethylene. Elements of the ethylene pathway that appear particularly promising in this respect include ethylene receptors as ETR1, and transcription factors such as EIN3. Both direct and indirect approaches seem to be successful, nevertheless, although genetic transformation using recombinant DNA has the ability to save much time in the breeding process, they are not readily used by breeders yet. This is primarily due to legislative issues, economic issues, difficulties of implementing this technology in some ornamental plants, as well as how these techniques are publically perceived, particularly in Europe. Recently, newer and more precise genome-editing techniques have become available and they are already being implemented in some crops. New breeding techniques may help change the current situation and pave the way toward a legal and public acceptance if products of these technologies are indistinguishable from plants obtained by conventional techniques.
- Published
- 2015
- Full Text
- View/download PDF
46. Evaluation of reproductive barriers contributes to the development of novel interspecific hybrids in the Kalanchoë genus.
- Author
-
Kuligowska K, Lütken H, Christensen B, Skovgaard I, Linde M, Winkelmann T, and Müller R
- Subjects
- Crosses, Genetic, Flowers genetics, Genetic Variation, Genotype, Germination, Kalanchoe anatomy & histology, Kalanchoe cytology, Phylogeny, Pollen Tube growth & development, Reproduction, Seeds genetics, Seeds growth & development, Species Specificity, Hybridization, Genetic, Kalanchoe genetics, Kalanchoe physiology
- Abstract
Background: Interspecific hybridization is a useful tool in ornamental breeding to increase genetic variability and introduce new valuable traits into existing cultivars. The successful formation of interspecific hybrids is frequently limited by the presence of pre- and post-fertilization barriers. In the present study, we investigated the nature of hybridization barriers occurring in crosses between Kalanchoë species and evaluated possibilities of obtaining interspecific hybrids., Results: The qualitative and quantitative analyses of pollen tube growth in situ were performed following intra- and interspecific pollinations. They revealed occurrence of pre-fertilization barriers associated with inhibition of pollen germination on the stigma and abnormal growth of pollen tubes. Unilateral incongruity related to differences in pistil length was also observed. The pollen quality was identified as a strong factor influencing the number of pollen tubes germinating in the stigma. In relation to post-fertilization barriers, endosperm degeneration was a probable barrier hampering production of interspecific hybrids. Moreover, our results demonstrate the relation of genetic distance estimated by AFLP marker analysis of hybridization partners with cross-compatibility of Kalanchoë species. At the same time, differences in ploidy did not influence the success of interspecific crosses., Conclusions: Our study presents the first comprehensive analysis of hybridization barriers occurring within Kalanchoë genus. Reproductive barriers were detected on both, pre- and post-fertilization levels. This new knowledge will contribute to further understanding of reproductive isolation of Kalanchoë species and facilitate breeding of new cultivars. For the first time, interspecific hybrids between K. nyikae as maternal plant and K. blossfeldiana as well as K. blossfeldiana and K. marnieriana were generated.
- Published
- 2015
- Full Text
- View/download PDF
47. Transformation of miniature potted rose (Rosa hybrida cv. Linda) with P( SAG12 )-ipt gene delays leaf senescence and enhances resistance to exogenous ethylene.
- Author
-
Zakizadeh H, Lütken H, Sriskandarajah S, Serek M, and Müller R
- Subjects
- Agrobacterium tumefaciens, Alkyl and Aryl Transferases metabolism, Arabidopsis genetics, Arabidopsis Proteins metabolism, Cellular Senescence, Chlorophyll analysis, Cysteine Endopeptidases metabolism, Cytokinins pharmacology, Darkness, Gene Expression Regulation, Enzymologic, Genetic Vectors, Plant Leaves drug effects, Plant Leaves genetics, Plant Leaves physiology, Plant Roots drug effects, Plant Roots genetics, Plant Roots physiology, Plant Shoots drug effects, Plant Shoots genetics, Plant Shoots physiology, Plant Somatic Embryogenesis Techniques, Plants, Genetically Modified, Rosa drug effects, Rosa physiology, Transformation, Genetic, Up-Regulation, Alkyl and Aryl Transferases genetics, Arabidopsis Proteins genetics, Cysteine Endopeptidases genetics, Ethylenes pharmacology, Gene Expression Regulation, Plant, Plant Growth Regulators pharmacology, Rosa genetics
- Abstract
KEY MESSAGE : The P ( SAG12 ) -ipt gene was transferred to miniature rose, as the first woody species, resulting in increased ethylene resistance due to specific up-regulation of the ipt gene under senescence promoting conditions. Transgenic plants of Rosa hybrida 'Linda' were obtained via transformation with Agrobacterium tumefaciens strain harboring the binary vector pSG529(+) containing the P( SAG12 )-ipt construct. A. tumefaciens strains AGL1, GV3850 and LBA4404 (containing P(35S)-INTGUS gene) were used for transformation of embryogenic callus, but transgenic shoots were obtained only when AGL1 was applied. The highest transformation frequency was 10 % and it was achieved when half MS medium was used for the dilution of overnight culture of Agrobacterium. Southern blot confirmed integration of 1-6 copies of the nptII gene into the rose genome in the tested lines. Four transgenic lines were obtained which were morphologically true-to-type and indistinguishable from Wt shoots while they were in in vitro cultures. Adventitious root induction was more difficult in transgenic shoots compared to the Wt shoots, however, one of the transgenic lines (line 6) was rooted and subsequently analyzed phenotypically. The ipt expression levels were determined in this line after exposure to exogenous ethylene (3.5 μl l(-1)) and/or darkness. Darkness resulted in twofold up-regulation of ipt expression, whereas darkness combined with ethylene caused eightfold up-regulation in line 6 compared to Wt plants. The transgenic line had significantly higher content of chlorophyll at the end of the treatment period compared to Wt plants.
- Published
- 2013
- Full Text
- View/download PDF
48. Overexpression of the AtSHI gene in poinsettia, Euphorbia pulcherrima, results in compact plants.
- Author
-
Islam MA, Lütken H, Haugslien S, Blystad DR, Torre S, Rolcik J, Rasmussen SK, Olsen JE, and Clarke JL
- Subjects
- Agrobacterium tumefaciens genetics, Euphorbia anatomy & histology, Flowers anatomy & histology, Flowers genetics, Germination genetics, Indoleacetic Acids metabolism, Plant Growth Regulators metabolism, Plant Leaves anatomy & histology, Promoter Regions, Genetic, RNA, Messenger genetics, Transformation, Genetic, Transgenes, Arabidopsis Proteins genetics, Caulimovirus genetics, Euphorbia genetics, Gene Expression, Genes, Plant, Plant Leaves genetics, Plants, Genetically Modified anatomy & histology, Transcription Factors genetics
- Abstract
Euphorbia pulcherrima, poinsettia, is a non-food and non-feed vegetatively propagated ornamental plant. Appropriate plant height is one of the most important traits in poinsettia production and is commonly achieved by application of chemical growth retardants. To produce compact poinsettia plants with desirable height and reduce the utilization of growth retardants, the Arabidopsis SHORT INTERNODE (AtSHI) gene controlled by the cauliflower mosaic virus 35S promoter was introduced into poinsettia by Agrobacterium-mediated transformation. Three independent transgenic lines were produced and stable integration of transgene was verified by PCR and Southern blot analysis. Reduced plant height (21-52%) and internode lengths (31-49%) were obtained in the transgenic lines compared to control plants. This correlates positively with the AtSHI transcript levels, with the highest levels in the most dwarfed transgenic line (TL1). The indole-3-acetic acid (IAA) content appeared lower (11-31% reduction) in the transgenic lines compared to the wild type (WT) controls, with the lowest level (31% reduction) in TL1. Total internode numbers, bract numbers and bract area were significantly reduced in all transgenic lines in comparison with the WT controls. Only TL1 showed significantly lower plant diameter, total leaf area and total dry weight, whereas none of the AtSHI expressing lines showed altered timing of flower initiation, cyathia abscission or bract necrosis. This study demonstrated that introduction of the AtSHI gene into poinsettia by genetic engineering can be an effective approach in controlling plant height without negatively affecting flowering time. This can help to reduce or avoid the use of toxic growth retardants of environmental and human health concern. This is the first report that AtSHI gene was overexpressed in poinsettia and transgenic poinsettia plants with compact growth were produced.
- Published
- 2013
- Full Text
- View/download PDF
49. Genetic engineering and sustainable production of ornamentals: current status and future directions.
- Author
-
Lütken H, Clarke JL, and Müller R
- Subjects
- DNA, Recombinant, Ethylenes metabolism, Genetic Engineering methods, Gibberellins metabolism, Plant Growth Regulators metabolism, Plants, Genetically Modified growth & development, Plants, Genetically Modified metabolism, Signal Transduction, Transformation, Genetic, Breeding, Genetic Engineering trends, Plants, Genetically Modified genetics
- Abstract
Through the last decades, environmentally and health-friendly production methods and conscientious use of resources have become crucial for reaching the goal of a more sustainable plant production. Protection of the environment requires careful consumption of limited resources and reduction of chemicals applied during production of ornamental plants. Numerous chemicals used in modern plant production have negative impacts on human health and are hazardous to the environment. In Europe, several compounds have lost their approval and further legal restrictions can be expected. This review presents the more recent progress of genetic engineering in ornamental breeding, delivers an overview of the biological background of the used technologies and critically evaluates the usefulness of the strategies to obtain improved ornamental plants. First, genetic engineering is addressed as alternative to growth retardants, comprising recombinant DNA approaches targeting relevant hormone pathways, e.g. the gibberellic acid (GA) pathway. A reduced content of active GAs causes compact growth and can be facilitated by either decreased anabolism, increased catabolism or altered perception. Moreover, compactness can be accomplished by using a natural transformation approach without recombinant DNA technology. Secondly, metabolic engineering approaches targeting elements of the ethylene signal transduction pathway are summarized as a possible alternative to avoid the use of chemical ethylene inhibitors. In conclusion, molecular breeding approaches are dealt with in a way allowing a critical biological assessment and enabling the scientific community and public to put genetic engineering of ornamental plants into a perspective regarding their usefulness in plant breeding.
- Published
- 2012
- Full Text
- View/download PDF
50. Expression of KxhKN4 and KxhKN5 genes in Kalanchoë blossfeldiana 'Molly' results in novel compact plant phenotypes: towards a cisgenesis alternative to growth retardants.
- Author
-
Lütken H, Laura M, Borghi C, Ørgaard M, Allavena A, and Rasmussen SK
- Subjects
- Amino Acid Sequence, Chlorophyll analysis, Cloning, Molecular, Gene Expression Regulation, Plant, Genetic Engineering methods, Homeodomain Proteins genetics, Kalanchoe genetics, Molecular Sequence Data, Plant Leaves metabolism, Plant Proteins genetics, Plants, Genetically Modified genetics, Plants, Genetically Modified growth & development, RNA Interference, Homeodomain Proteins metabolism, Kalanchoe growth & development, Phenotype, Plant Proteins metabolism
- Abstract
Many potted plants like Kalanchoë have an elongated natural growth habit, which has to be controlled through the application of growth regulators. These chemicals will be banned in the near future in all the EU countries. Besides their structural functions, the importance of homeotic genes to modify plant architecture appears evident. In this work, the full length cDNA of five KNOX (KN) genes were sequenced from K. x houghtonii, a viviparous hybrid. Two constructs with the coding sequence of the class I and class II homeobox KN genes, KxhKN5 and KxhKN4, respectively, were overexpressed in the commercially important ornamental Kalanchoë blossfeldiana 'Molly'. Furthermore, a post-transcriptional gene silencing construct was made with a partial sequence of KxhKN5 and also transformed into 'Molly'. Several transgenic plants exhibited compact phenotypes and some lines had a relative higher number of inflorescences. A positive correlation between gene expression levels and the degree of compactness was found. However, a correlation between the induced phenotypes and the number of inserted copies of the transgene were not observed, although line '70-10' with a high copy number also had the highest expression level. Moreover, overexpression of KxhKN4 resulted in plants with dark green leaves due to an elevated content of chlorophyll, a highly desired property in the ornamental plant industry. These transgenic plants show that a cisgenesis approach towards production of compact plants with improved quality as an alternative to chemical growth retardants may be feasible.
- Published
- 2011
- Full Text
- View/download PDF
Catalog
Discovery Service for Jio Institute Digital Library
For full access to our library's resources, please sign in.