218 research outputs found
Growth enhancement of grapevine call us by catechin on auxin-free media
Proliferating SpÀtburgunder cells cultured in vitro were found to synthesize the monomeric and oligomeric flavanols catechin, C2, B3, B1, B2 prodelphinidin, ECG (epicatechin gallate), B2G, B2-gallate and B5. Catechin and prodelphinidin were the predominating compounds of all calli studied. Growth promotion of calli from Spatburgunder and Romulus was studied using MS media containing benzyladenine (BA) alone (control), BA plus catechin, and BA combined with two different concentrations of indole-3-acetic acid (IAA). Growth on BA alone was notably reduced. Catechin (68 ”M) stimulated callus growth several-fold when combined with 0.8 ”M BA; however, this effect was only observed with explants excised from internodes of vigorously growing young shoots
Flavanols in grapevine: In vitro accumulation and defence reactions in shoots
Callus of two grapevine cultivars was cultivated for 4 weeks on MS-medium, half strength, which was additionally supplemented with abscisic acid (ABA), (+)-catechin or a combination of both. (+)-Catechin did not elevate the pool size of the callus flavanols. Application of 3 % sucrose caused a significant increase of the callus flavanols, whereas the response to ABA was quite variable. Leaves and shoots of cv. Spatburgunder (Pinot noir) were examined histologically on the mode of flavanol deposition. The flavanols of the leaf mesophyll were spread evenly throughout the central vacuole whereas those of the outer shoot cortex were confined to special intravacuolar globules. The amorphous leaf flavanols were converted into globdar ones in the vicinity of fungal infections. Apparently, the central vacuole acquires special adjustment under the influence of infection stress. When paraquat was applied to the shoots, amorphous material was attached towards the cell walls. Additionally, the globular flavanols disappeared which could be reversed by addition of (+)-catechin. Thus, (+)-catechin diminished the oxidative damage caused by the oxygen radical producing herbicide. (+)-Catechin and epicatechin are the dominant flavanols of the leaves, whereas the dimeric proanthocyanidins B3 and B1 (PAs) predominate in the callus
The inheritance of the hypersensitivity resistance of European plum (Prunus domestica L.) against the Plum pox virus
In between 2003 and 2009 more than 500 seedlings have been tested for hypersensitivity resistance against the Plum pox virus (PPV), which causes Sharka disease. The seedlings had at least one hypersensitive parent genotype. They were tested for hypersensitivity resistance by double grafting onto PPV infected interstem in the green house. In crossing combinations with two hypersensitive parents the percentage of hypersensitive seedlings was highest. There is also no equal distribution of the genotypes over the individual hypersensitivity classes (HC) in all crossing combinations. The percentage of hypersensitive seedlings strongly depends on the parentage. Furthermore investigations regarding the origin of the hypersensitivity resistance of the cultivar âJojoâ, which is a descendant of a crossing combination from âOrtenauerâ Ă âStanleyâ, were done. It was shown that the cultivar âOrtenauerâ is the donor of the hypersensitivity trait.Keywords: Plum pox virus, hypersensitivity, inheritance, Prunus domestica L., resistanc
Preliminary studies on the use of the Cascade Rolling Circle Amplification technique for Plum pox virus detection
Isothermal techniques for the amplification of nucleic acids have emerged in the last years. In contrast to the Polymerase chain reaction (PCR), the most prevalent method to amplify DNA in vitro, the reactions can be run at constant temperatures. Specificity and sensitivity are at least as high as that obtained by using PCR and the methods are less time consuming. Therefore, the isothermal amplification of nucleic acids provides a powerful tool for the detection of Plum pox virus (PPV), the causal agent of the Sharka disease. The cascade rolling circle amplification (CRCA), first described by Thomas et al. (1999), is based on the rolling circle mechanism that many viruses use to replicate their genome multiplicatively. Circular Probes, also called Padlock probes (PLP), which arise from the ligation of the terminal region of DNA probes upon side by side hybridization to the target serve as template (Nilsson et al. 1994).For detecting PPV by CRCA, RNA was extracted and reverse transcribed to cDNA using a PPV specific primer. Several PLPs with varying lengths and sequences complementary region to the cDNA were designed and tested. Furthermore, different pairs of primers for the subsequent amplification were developed. For specific ligation Ampligase and T4 DNA Ligase were tested. In CRCA, two polymerases with strong strand displacement activity were compared: Phi29 DNA Polymerase and Bst DNA Polymerase. These enzymes differ in their optimal reaction temperature.Ligation as well as amplification do occur, but there is high background amplification also in negative and no template controls. Discrimination was possible after a restriction digestion is carried out. As proven by sequencing of reaction products non-specific signals were a result of primer polymerization. Current work focuses on the reduction of the background amplification and improvement of the sensitivity. Keywords: Cascade Rolling Circle Amplification, CRCA, isothermal amplification of DNA, Plum pox virus, PP
The hypersensitivity resistance of european plum to the Plum pox virus and its potential impact on the epidemiology of the virus
Since the detection of the Plum pox virus (PPV) different strategies for Sharka containment were developed. One of the most important one is the breeding of resistant cultivars. Other than in Prunus persica and in Prunus armeniaca, in Prunus domestica a type of natural resistance was detected which seems to be able to prevent the spread of PPV both over long and short distances. Therefore, this type of Sharka resistance which is based on a hypersensitive response and has been stable for more than 20 years is suggested to have the most beneficial impact on the epidemiology of the virus compared to other mechanisms of resistance or tolerance.Keywords: Sharka containment, Prunus domestica, plum breedin
Ganzheitliche Untersuchungsmethoden zur Erfassung und PrĂŒfung der QualitĂ€t ökologischer Lebensmittel: Stand der Entwicklung und Validierung
In dem wachsenden Markt ökologischer Lebensmittel werden Methoden zur produktorientierten QualitÀtserfassung gefordert. Dabei geht es u.a. um die Unterscheidung von Produkten aus unterschiedlichen Anbauverfahren.
Die Ziele des Projektes waren daher:
1. ausgewĂ€hlte ganzheitliche Methoden gemÀà ISO 17025 zu validieren, d.h. Laborprozesse festzulegen, sowie EinflussgröĂen und Verfahrensmerkmale zu bestimmen,
2. zu testen, ob diese Verfahren eine Differenzierung von definierten Proben statistisch abgesichert zeigen können.
.
Diese Ziele konnten erreicht werden. Es wurde bestÀtigt, dass einige der Methoden auf Grundlage dokumentierter Prozeduren Lebensmittel aus definierten Anbauversuchen (u.a. aus dem DOK-Versuch am FIBL/CH) reproduzierbar unterscheiden können.
Die Koordination und die Validierung der Kupferchlorid-Kristallisation sowie die Messung der Polyphenole lag bei der UniversitĂ€t Kassel, FG Ăkologische LebensmittelqualitĂ€t und ErnĂ€hrungskultur. Die KWALIS GmbH, Dipperz, validierte die Fluoreszenz-Anregungsspektroskopie und die Bestimmung des Physiologischen AminosĂ€urestatus, die EQC GmbH, Weidenbach die elektrochemischen Messungen. Dr. Kromidas, SaarbrĂŒcken ĂŒbernahm die Beratung der Validierungsprozeduren.
.
An Blindproben wurde untersucht, ob die Verfahren fĂŒr Weizen- und Möhrenproben aus definierten Anbau- und Sortenversuchen geeignet sind (Fragestellung der Validierung). Die Proben wurden von unabhĂ€ngiger Stelle (OEL-FAL, Trenthorst) codiert. Die Proben wurden gleichzeitig an alle Partner versandt; dadurch konnten die Methoden auch untereinander verglichen werden.
Die Methoden Kupferchlorid-Kristallisation, Fluoreszenz-Anregungsspektroskopie und Physiologischer AminosĂ€urestatus sind fĂŒr die Fragestellung geeignet. Mit allen drei Methoden konnten die Proben differenziert und gruppiert werden. DarĂŒber hinaus konnten mit der Fluoreszenz-Anregungsspektroskopie und ĂŒber den physiologischen AminosĂ€urestatus die Proben auch den Anbauweisen richtig zugeordnet werden. Allerdings ist damit noch keine Aussage ĂŒber die FĂ€higkeit dieser Verfahren möglich, generell Proben aus ökologischer und konventioneller Herkunft zu unterscheiden. DafĂŒr sind weitere Untersuchungen sowohl an Proben definierter Herkunft als auch an Marktproben notwendig
Transgenic apple plants overexpressing the chalcone 3-hydroxylase gene of Cosmos sulphureus show increased levels of 3-hydroxyphloridzin and reduced susceptibility to apple scab and fire blight
Main conclusionOverexpression of chalcone-3-hydroxylase provokes increased accumulation of 3-hydroxyphloridzin inMalus. Decreased flavonoid concentrations but unchanged flavonoid class composition were observed. The increased 3-hydroxyphlorizin contents correlate well with reduced susceptibility to fire blight and scab.The involvement of dihydrochalcones in the apple defence mechanism against pathogens is discussed but unknown biosynthetic steps in their formation hamper studies on their physiological relevance. The formation of 3-hydroxyphloretin is one of the gaps in the pathway. Polyphenol oxidases and cytochrome P450 dependent enzymes could be involved. Hydroxylation of phloretin in position 3 has high similarity to the B-ring hydroxylation of flavonoids catalysed by the well-known flavonoid 3âČ-hydroxylase (F3âČH). Using recombinant F3âČH and chalcone 3-hydroxylase (CH3H) from Cosmos sulphureus we show that F3âČH and CH3H accept phloretin to some extent but higher conversion rates are obtained with CH3H. To test whether CH3H catalyzes the hydroxylation of dihydrochalcones in planta and if this could be of physiological relevance, we created transgenic apple trees harbouring CH3H from C. sulphureus. The three transgenic lines obtained showed lower polyphenol concentrations but no shift between the main polyphenol classes dihydrochalcones, flavonols, hydroxycinnamic acids and flavan 3-ols. Increase of 3-hydroxyphloridzin within the dihydrochalcones and of epicatechin/catechin within soluble flavan 3-ols were observed. Decreased activity of dihydroflavonol 4-reductase and chalcone synthase/chalcone isomerase could partially explain the lower polyphenol concentrations. In comparison to the parent line, the transgenic CH3H-lines showed a lower disease susceptibility to fire blight and apple scab that correlated with the increased 3-hydroxyphlorizin contents.Austrian Sci-ence Fund (FWF
Environmentally induced changes in antioxidant phenolic compounds levels in wild plants
[EN] Different adverse environmental conditions cause oxidative stress in plants by generation of reactive
oxygen species (ROS). Accordingly, a general response to abiotic stress is the activation of enzymatic and non-enzymatic antioxidant systems. Many phenolic compounds, especially flavonoids, are known antioxidants and efficient ROS scavengers in vitro, but their exact role in plant stress responses in nature is still under debate. The aim of our work is to investigate this role by correlating the degree of
environmental stress with phenolic and flavonoid levels in stress-tolerant plants. Total phenolic and antioxidant flavonoid contents were determined in 19 wild species. Meteorological data and plant and soil samples were collected in three successive seasons from four Mediterranean ecosystems: salt marsh, dune, semiarid and gypsum habitats. Changes in phenolic and flavonoid levels were correlated
with the environmental conditions of the plants and were found to depend on both the taxonomy and ecology of the investigated species. Despite species-specific differences, principal component analyses of the results established a positive correlation between plant phenolics and several environmental parameters, such as altitude, and those related to water stress: temperature, evapotranspiration, and soil water deficit. The correlation with salt stress was, however, very weak. The joint analysis of all the species showed the lowest phenolic and flavonoid levels in the halophytes from the salt marsh. This finding supports previous data indicating that the halophytes analysed here do not undergo oxidative stress in their natural habitat and therefore do not need to activate antioxidant systems as a defence against salinity.This work has been funded by the Spanish Ministry of Science and Innovation (Project CGL2008-00438/BOS), with contribution from the European Regional Development Fund. Thanks to Dr. Rafael Herrera for critical reading of the manuscript.Bautista, I.; Boscaiu, M.; LidĂłn, A.; Llinares Palacios, JV.; Lull, C.; Donat-Torres, MP.; Mayoral GarcĂa-Berlanga, O.... (2016). Environmentally induced changes in antioxidant phenolic compounds levels in wild plants. Acta Physiologiae Plantarum. 38(1):1-15. https://doi.org/10.1007/s11738-015-2025-2S115381Agati G, Biricolti S, Guidi L, Ferrini F, Fini A, Tattini M (2011) The biosynthesis of flavonoids is enhanced similarly by UV radiation and root zone salinity in L. vulgare leaves. J Plant Physiol 168:204â212Agati G, Brunetti C, Di Ferdinando M, Ferrini F, Pollastri S, Tattini M (2013) Functional roles of flavonoids in photoprotection: new evidence, lessons from the past. Plant Physiol Biochem 72:35â45Albert A, Sareedenchai V, Heller W, Seidlitz HK, Zidorn C (2009) Temperature is the key to altitudinal variation of phenolics in Arnica montana L. cv. ARBO. Oecologia 160:1â8Appel K, Hirt H (2004) Reactive oxygen species: metabolism, oxidative stress, and signal transduction. Annu Rev Plant Biol 55:373â399Bachereau F, Marigo G, Asta J (1998) Effect of solar radiation (UV and visible) at high altitude on CAM-cycling and phenolic compounds biosynthesis in Sedum album. Physiol Plant 104:203â210Ballizany WL, Hofmann RV, Jahufer MZZ, Barrett BB (2012) Multivariate associations of flavonoid and biomass accumulation in white clover (Trifolium repens) under drought. Funct Plant Biol 39:167â177Bieza K, Lois R (2001) An Arabidopsis mutant tolerant to lethal ultraviolet-B levels shows constitutively elevated accumulation of flavonoids and other phenolics. Plant Physiol 126:1105â1115Bilger W, Rolland M, Nybakken L (2007) UV screening in higher plants induced by low temperature in the absence of UV-B radiation. Photochem Photobiol Sci 6:190â195Blumthaler M, Ambach M, Ellinger R (1997) Increase in solar UV radiation with altitude. J Photochem Photobiol B 39:130â134Boscaiu M, Lull C, Llinares J, Vicente O, Boira H (2013) Proline as a biochemical marker in relation to the ecology of two halophytic Juncus species. J Plant Ecol 6:177â186Bose J, Rodrigo-Moreno A, Shabala S (2013) ROS homeostasis in halophytes in the context of salinity stress tolerance. J Exp Bot 65:1241â1257Brown DE, Rashotte AM, Murphy AS, Normanly J, Tague BW, Peer WA, Taiz L, Muday GK (2001) Flavonoids act as a negative regulators of auxin transport in vivo in Arabidopsis. Plant Physiol 126:524â535Burchard P, Bilger W, Weissenböck G (2000) Contribution of hydroxycinnamates and flavonoids to epidermal shielding of UV-A and UV-B radiation in developing rye primary leaves as assessed by ultraviolet-induced chlorophyll fluorescence measurements. Plant Cell Environ 23:1373â1380Burriel F, Hernando V (1947) Nuevo mĂ©todo para determinar el fĂłsforo asimilable en los suelos. Anales de EdafologĂa FisiologĂa Vegetal 9:611â622Cheynier V, Comte G, Davies KM, Lattanzio V, Martens S (2013) Plant phenolics: recent advances on their biosynthesis, genetics, and ecophysiology. Plant Physiol Biochem 72:1â20Coman C, Rugina OD, Socaciu C (2012) Plants and natural compounds with antidiabetic action. Not Bot Horti Agrobo 40:314â325Di Ferdinando M, Brunetti C, Fini A, Tattini M (2012) Flavonoids as antioxidants in plants under abiotic stresses. In: Ahmad P, Prasad MNV (eds) Abiotic stress responses in plants: metabolism, productivity and sustainability. Springer, New York, pp 159â179Di Ferdinando M, Brunetti C, Agati G, Tattini M (2014) Multiple functions of polyphenols in plants inhabiting unfavourable Mediterranean areas. Environ Exper Bot 103:107â116FAO (1990) Management of gypsiferous soils. FAO Soils Bull, p 62Fini A, Brunetti C, Di Ferdinando M, Ferrini F, Tattini M (2011) Stress-induced flavonoid biosynthesis and the antioxidant machinery of plants. Plant Signal Behav 6:709â711Gil R, Lull C, Boscaiu M, Bautista I, LidĂłn A, Vicente O (2011) Soluble carbohydrates as osmolytes in several halophytes from a Mediterranean salt marsh. Not Bot Horti Agrobo 39:9â17Gil R, Bautista I, Boscaiu M, LidĂłn A, Wankhade S, SĂĄnchez H, Llinares J, Vicente O (2014) Responses of five Mediterranean halophytes to seasonal changes in environmental conditions. AoB Plants 6: plu049Gould KS, Lister C (2006) Flavonoid function in plants. In: Andersen ĂM, Marham KR (eds) Flavonoids, chemistry, biochemistry and application. CRC Press, Boca Raton, pp 397â442Hajimahmoodi M, Moghaddam G, Ranjbar AM, Khazani H, Sadeghi N, Oveisi MR, Jannat B (2013) Total phenolic, flavonoids, tannin content and antioxidant power of some Iranian pomegranate flower cultivars (Punica granatum L.). Am J Plant Sci 4:1815â1820Halliwell B (2006) Reactive species and antioxidants. Redox biology is a fundamental theme of aerobic life. Plant Physiol 141:312â322Harborne JB, Williams C (2000) Advances in flavonoid research since 1992. Phytochemistry 55:481â504HernĂĄndez I, Alegre L, MunnĂ©-Bosch S (2004) Drought-induced changes in flavonoids and other low molecular weight antioxidants in Cistus clusii grown under Mediterranean field conditions. Tree Physiol 24:1303â1311HernĂĄndez I, Alegre L, Van Breusegem F, MunnĂ©-Bosch S (2008) How relevant are flavonoids as antioxidants in plants? Trends Plant Sci 14:125â132Iwashina T (2000) The structure and distribution of the flavonoids in plants. J Plant Res 113:287â299Jaakola L, MÀÀttĂ€-Riihinen K, KĂ€renlampi S, Hohtola A (2004) Activation of flavonoid biosynthesis by solar radiation in bilberry (Vaccinium myrtillus L.) leaves. Planta 218:721â728Jenkins GI (2009) Signal transduction in responses to UB-B radiation. Annu Rev Plant Biol 60:407â431Jenkins GI, Long JC, Wade HK, Shenton MR, Bibikova TN (2001) UV and blue light signalling: pathways regulating chalcone synthase gene expression in Arabidopsis. New Phytol 151:121â131Kaulen H, Schell J, Kreuzaler F (1986) Light-induced expression of the chimeric chalcone synthase-NPTII gene in tobacco cells. EMBO J 5:1â8Kim DO, Jeong SW, Lee CY (2003) Antioxidant capacity of phenolic phytochemicals from various cultivars of plums. Food Chem 81:321â326Kirakosyan A, Seymour E, Kaufman PB, Warber S, Bolling S, Chang SC (2003) Antioxidant capacity of polyphenolic extracts from leaves of Crataegus laevigata and Crataegus monogyna (Hawthorn) subjected to drought and cold stress. J Agr Food Chem 51:3973â3976Knudssen D, Peterson GA, Pratt PF (1982) Lithium, Sodium and Potassium. In: Page AL et al (eds) Methods of soil analysis, chemical and microbiological properties. American Society of Agronomy, Madison, pp 225â246Koes RE, Spelt CE, Mol JNM (1989) The chalcone synthase multigene family of Petunia hybrida (V30): differential, light-regulated expression during flower development and UV light induction. Plant Mol Biol 12:213â225Körner C (1999) Alpine plant life. Functional plant ecology of high mountain ecosytems, BerlinKumar S, Pandey AK (2013) Chemistry and biological activities of flavonoids: an overview. Sci World J 2013:1â16Kuo S (1996) Phosphorus. In: Spark D (ed) Methods of soil analysis: chemical methods, part 3. American Society of Agronomy, Madison, pp 869â919Lavola A (1998) Accumulation of flavonoids and related compounds in birch induced by UV-B irradiance. Tree Physiol 18:53â58Li J, Ou-Lee TM, Raba R, Amundson RG, Last RL (1993) Arabidopsis flavonoid mutants are hypersensitive to UV-B radiation. Plant Cell 5:171â179Llinares JV, Bautista I, Donat MP, LidĂłn A, Lull C, Mayoral O, Wankhade S, Boscaiu M, Vicente O (2015) Responses to environmental stress in plants adapted to Mediterranean gypsum habitats. Not Sci Biol 7:34â44Marinova D, Ribarova F, Atanassova M (2005) Total phenolics and total flavonoids in Bulgarian fruits and vegetables. J Univ Chem Technol Metall 40:255â260Martens H, Naes T (1989) Multivariate calibration. Wiley, New YorkMurai Y, Takemura S, Takeda K, Kitajima K, Iwashina T (2009) Altitudinal variation of UV-absorbing compounds in Plantago asiatica. Biochem Syst Ecol 37:78â384Nakabayashi R, Yonekura-Sakakibara K, Urano K, Suzuki M, Yamada Y, Nishizawa T, Matsuda F, Kojima M, Sakakibara H, Shinozaki K, Michael AJ, Tohge T, Yamazaki M, Saito K (2014) Enhancement of oxidative and drought tolerance in Arabidopsis by overaccumulation of antioxidant flavonoids. Plant J 77:367â379Napoli CA, Fahy D, Wang HY, Taylor LP (1999) white anther: a petunia mutant that abolishes pollen flavonoid accumulation, induces male sterility, and is complemented by a chalcone synthase transgene. Plant Physiol 120:615â622Nechita A, Cotea VV, Nechita CB, Pincu RR, Mihai CT, Colibaba CL (2012) Study of cytostatic and cytotoxic activity of several polyphenolic extracts obtained from Vitis vinifera. Not Bot Horti Agrobo 40:216â221Nelson DW, Sommers LE (1982) Total carbon, organic carbon, and organic matter. In: Page AL et al (eds) Methods of soil analysis, chemical and microbiological properties. Soil Science Society of America, Madison, pp 539â577Nelson RE, Klameth LC, Nettleton WD (1978) Determining soil gypsum content and expressing properties of gypsiferous soils. Soil Sci Soc Am J 42:659â661Nile SH, Khobragade CN (2010) Antioxidant activity and flavonoid derivatives of Plumbago zeylanica. J Nat Prod 3:130â133Park HL, Lee SW, Jung KH, Hahn TR, Cho MH (2013) Transcriptomic analysis of UV-treated rice leaves reveals UV-induced phytoalexin biosynthetic pathways and their regulatory networks in rice. Phytochemistry 96:57â71PÄkal A, Pyrzynska K (2014) Evaluation of aluminium complexation reaction for flavonoid content assay. Food Anal Method 7:1776â1782Pollastri S, Tattini M (2011) Flavonols: old compounds for old roles. Ann Bot 108:1225â1233Ravishankar D, Rajora AK, Greco F, Osborn HM (2013) Flavonoids as prospective compounds for anti-cancer therapy. Int J Biochem Cell B 45:2821â2831Rice-Evans CA, Miller NJ, Paganga G (1996) Structure-antioxidant activity relationships of flavonoids and phenolic acids. Free Radical Bio Med 20:933â956Rieger G, MĂŒller M, Guttenberger H, Bucar F (2008) Influence of altitudinal variation on the content of phenolic compounds in wild populations of Calluna vulgaris, Sambucus nigra, and Vaccinium myrtillus. J Agric Food Chem 58:9080â9086Rivas-MartĂnez S, Rivas-Saenz S (1996â2009) Worldwide bioclimatic classification system. Phytosociological Research Center, Spain. http://www.globalbioclimatics.org . Accessed 1 July 2013Rohman A, Riyanto S, Yuniarti N, Saputra WR, Utami R, Mulatsih W (2010) Antioxidant activity, total phenolic, and total flavonoid of extracts and fractions of red fruit (Pandanus conoideus Lam). Int Food Res J 17:97â106Romano B, Pagano E, Montanaro V, Fortunato AL, Milic N, Borrelli F (2013) Novel insights into the pharmacology of flavonoids. Phytother Res 27:1588â1596Rozema J, van de Staaij J, Björn LO, Caldwell MM (1997) UV-B as an environmental factor in plant life: stress and regulation. Trends Ecol Evol 12:22â28Rozema J, Bjorn LO, Bornman JF, GaberĆĄÄik A, HĂ€der DP, TroĆĄt T, Germ M, Klisch M, Gröniger A, Sinha RP, Lebert M, He YY, Buffoni-Hall R, de Bakker NVJ, van de Staaij J, Meijkamp BB (2002) The role of UV-B radiation in aquatic and terrestrial ecosystemsâan experimental and functional analysis of the evolution of UV-absorbing compounds. Photochem Photobiol B Biol 66:2â12Schulze-Lefert P, Dangl JL, Becker-AndrĂ© M, Hahlbrock K, Schulz W (1989) Inducible in vivo DNA footprints define sequences necessary for UV light activation of the parsley chalcone synthase gene. EMBO J 8:651â656Sena MM, Frighetto RTS, Valarini PJ, Tokeshi H, Poppi RJ (2002) Discrimination of management effects on soil parameters by using principal component analysis: a multivariate analysis case study. Soil Till Res 67:171â181Shulaev V, Oliver DJ (2006) Metabolic and proteomic markers for oxidative stress. New tools for reactive oxygen species research. Plant Physiol 141:367â372Singleton VL, Rossi JA Jr (1965) Colorimetry of total phenolics with phosphomolybdic phosphotungstic acid reagents. Am J EnolVitic 16:144â158Spitaler R, Winkler A, Lins I, Yanar S, Stuppner H, Zidorn C (2008) Altitudinal variation of phenolic contents in flowering heads of Arnica montana cv. ARBO: a 3-year comparison. J Chem Ecol 34:369â375Stapleton AE, Walbot V (1994) Flavonoids can protect maize DNA from the induction of UV radiation damage. Plant Physiol 105:881â889Takahashi M, Asada K (1988) Superoxide production in aprotic interior of chloroplast thylakoids. Arch Biochem Biophys 267:714â722Tattini M, Gravano E, Pinelli P, Mulinacci N, Romani A (2000) Flavonoids accumulate in leaves and glandular trichomes of Phillyrea latifolia exposed to excess solar radiation. New Phytol 148:69â77Tattini M, Galardi C, Pinelli P, Massai R, Remorini D, Agati G (2004) Differential accumulation of flavonoids and hydroxycinnamates in leaves of Ligustrum vulgare under excess light and drought stress. New Phytol 163:547â561Treutter D (2005) Significance of flavonoids in plant resistance and enhancement of their biosynthesis. Plant Biol 7:581â591Treutter D (2006) Significance of flavonoids in plant resistance: a review. Environ Chem Lett 4:147â157Van Breusegem F, Dat JF (2006) Reactive oxygen species in plant cell death. Plant Physiol 141:384â390Williams CA, Grayer RJ (2004) Anthocyanins and other flavonoids. Nat Prod Rep 21:539â573Winkel-Shirley B (2002) Biosynthesis of flavonoids and effect of stress. Curr Opin Plant Biol 5:218â223Ylstra B, Touraev A, Benito Moreno RM, Stöger E, van Tunen AA, Vicente O, Mol JNM, Heberle-Bors E (1992) Flavonols stimulate development, germination and tube growth of tobacco pollen. Plant Physiol 100:902â907Zhishen J, Mengcheng T, Jianming W (1999) The determination of flavonoid contents in mulberry and their scavenging effects on superoxide radicals. Food Chem 64:555â559Zidorn C, Schubert B, Stuppner H (2005) Altitudinal differences in the contents of phenolics in flowering heads of three members of the tribe Lactuceae (Asteraceae) occurring as introduced species in New Zealand. Biochem Syst Ecol 33:855â87
Comprehensive genetic dissection of wood properties in a widely-grown tropical tree: Eucalyptus
Background: Eucalyptus is an important genus in industrial plantations throughout the world and is grown for use as timber, pulp, paper and charcoal. Several breeding programmes have been launched worldwide to concomitantly improve growth performance and wood properties (WPs). In this study, an interspecific cross between Eucalyptus urophylla and E. grandis was used to identify major genomic regions (Quantitative Trait Loci, QTL) controlling the variability of WPs. Results: Linkage maps were generated for both parent species. A total of 117 QTLs were detected for a series of wood and end-use related traits, including chemical, technological, physical, mechanical and anatomical properties. The QTLs were mainly clustered into five linkage groups. In terms of distribution of QTL effects, our result agrees with the typical L-shape reported in most QTL studies, i.e. most WP QTLs had limited effects and only a few (13) had major effects (phenotypic variance explained > 15%). The co-locations of QTLs for different WPs as well as QTLs and candidate genes are discussed in terms of phenotypic correlations between traits, and of the function of the candidate genes. The major wood property QTL harbours a gene encoding a Cinnamoyl CoA reductase (CCR), a structural enzyme of the monolignol-specific biosynthesis pathway. Conclusions: Given the number of traits analysed, this study provides a comprehensive understanding of the genetic architecture of wood properties in this Eucalyptus full-sib pedigree. At the dawn of Eucalyptus genome sequence, it will provide a framework to identify the nature of genes underlying these important quantitative traits. (Résumé d'auteur
Relationship between the Sensory-Determined Astringency and the Flavanolic Composition of Red Wines
[EN] The relationship between the proanthocyanidin profile and the perceived astringency was assessed in 13 commercial Tempranillo red wines. The concentration and compositional information were obtained by liquid chromatography with diode array detection coupled to electrospray ionization mass spectrometry after acid-catalyzed depolymerization of wine proanthocyanidins in the presence of excess phloroglucinol. Statistical analysis of the results showed significant correlations between sensory and chemical determinations. Astringency was more affected by the subunit composition than by the total concentration or the average degree of polymerization of wine proanthocyanidins. Higher proportions of epicatechin (EC) subunits in extension positions and gallocatechin (GC) subunits in terminal positions were shown to increase astringency. On the contrary, the amount of epigallocatechin (EGC) in both extension and terminal positions was negatively correlated with the perceived astringency
- âŠ