1. The activation of iron deficiency responses of grapevine rootstocks is dependent to the availability of the nitrogen formsSarhan Khalil, Rebeka Strah, Arianna Lodovici, Petr Vojta, Federica De Berardinis, Jörg Ziegler, Maruša Pompe Novak, Laura Zanin, Nicola Tomasi, Astrid Forneck, Michaela Griesser, 2024, original scientific article Abstract: Background In viticulture, iron (Fe) chlorosis is a common abiotic stress that impairs plant development and leads to yield and quality losses. Under low availability of the metal, the applied N form (nitrate and ammonium) can play a role in promoting or mitigating Fe deficiency stresses. However, the processes involved are not clear in grapevine. Therefore, the aim of this study was to investigate the response of two grapevine rootstocks to the interaction between N forms and Fe uptake. This process was evaluated in a hydroponic experiment using two ungrafted grapevine rootstocks Fercal (Vitis berlandieri x V. vinifera) tolerant to deficiency induced Fe chlorosis and Couderc 3309 (V. riparia x V. rupestris) susceptible to deficiency induced Fe chlorosis. Results The results could differentiate Fe deficiency effects, N-forms effects, and rootstock effects. Interveinal chlorosis of young leaves appeared earlier on 3309 C from the second week of treatment with NO3 −/NH4 + (1:0)/- Fe, while Fercal leaves showed less severe symptoms after four weeks of treatment, corresponding to decreased chlorophyll concentrations lowered by 75% in 3309 C and 57% in Fercal. Ferric chelate reductase (FCR) activity was by trend enhanced under Fe deficiency in Fercal with both N combinations, whereas 3309 C showed an increase in FCR activity under Fe deficiency only with NO3 −/NH4 + (1:1) treatment. With the transcriptome analysis, Gene Ontology (GO) revealed multiple biological processes and molecular functions that were significantly regulated in grapevine rootstocks under Fe-deficient conditions, with more genes regulated in Fercal responses, especially when both forms of N were supplied. Furthermore, the expression of genes involved in the auxin and abscisic acid metabolic pathways was markedly increased by the equal supply of both forms of N under Fe deficiency conditions. In addition, changes in the expression of genes related to Fe uptake, regulation, and transport reflected the different responses of the two grapevine rootstocks to different N forms. Conclusions Results show a clear contribution of N forms to the response of the two grapevine rootstocks under Fe deficiency, highlighting the importance of providing both N forms (nitrate and ammonium) in an appropriate ratio in order to ease the rootstock responses to Fe deficiency. Keywords: vitis, iron uptake, chlorosis, nitrate, ammonium, RNA-Seq Published in DiRROS: 19.06.2024; Views: 27; Downloads: 11 Full text (9,52 MB) This document has many files! More... |
2. Combined effects of early season leaf removal and climatic conditions on aroma precursors in Sauvignon blanc grapesPaolo Sivilotti, Branka Škvarč, Lorena Butinar, Melita Sternad Lemut, Klemen Lisjak, Andreja Vanzo, 2017, original scientific article Abstract: Early leaf removal around the cluster zone is a common technique applied in cool climate viticulture, to regulate yield components and improve fruit quality. Despite the increasing amount of information on early leaf removal and its impact on total soluble solids, anthocyanins and polyphenols, less is known regarding aroma compounds. In order to verify the hypothesis that defoliation, applied before or after flowering, could impact the biosynthesis of thiol precursors, we performed a two year (2013 and 2014) experiment on Sauvignon blanc. We provided evidence that differential accumulation of thiols precursors in berries is affected by the timing of defoliation and this impact was related to modifications in biosynthetic pathway. Furthermore, the possible interaction between leaf removal treatment and seasonal weather conditions, and its effect on the biosynthesis of volatile precursors are discussed. Our results suggested that in Sauvignon blanc the relative proportion of 4-S-glutathionyl-4-methylpentan-2-one (G-4MSP) and 3-S-glutathionylhexan-1-ol (G-3SH) precursors can be affected by defoliation, and this could be related to the induction of two specific genes encoding glutathione-S-transferases (VvGST3 and VvGST5), while no significant effects on basic fruit chemical parameters, polyphenols and methoxypyrazines were ascertained under our experimental conditions. Keywords: early leaf removal, cluster exposure, thiol precursors, methoxypyrazines, Vitis vinifera Published in DiRROS: 06.09.2022; Views: 543; Downloads: 238 Link to full text |
3. Poročilo o preskusu št.: LVG 2019-106 : opis vzorca: 11131748: Vitis vinifera, drugo, 11131939: Vitis vinifera, drugo, 11460442: Vitis vinifera, drugo : namen testiranja: sum na: Xylosandrus crassiusculusAndreja Kavčič, 2019, expertise, arbitration decision Keywords: varstvo gozdov, Vitis vinifera, Xylosandrus crassiusculus, žuželke, morfološke analize Published in DiRROS: 10.10.2019; Views: 1758; Downloads: 113 This document has many files! More... |
4. Poročilo o preskusu št.: LVG 2019-101 : opis vzorca: 11131878: Vitis vinifera, drugo, 11460138: Vitis vinifera, drugo, 11460060: Vitis vinifera, drugo : namen testiranja: sum na: Xylosandrus crassiusculusAndreja Kavčič, 2019, expertise, arbitration decision Keywords: varstvo gozdov, Vitis vinifera, Xylosandrus crassiusculus, žuželke, morfološke analize Published in DiRROS: 10.10.2019; Views: 1747; Downloads: 116 This document has many files! More... |
5. Poročilo o preskusu št.: LVG 2019-099 : opis vzorca: 11131731: Vitis vinifera, drugo, 11131922: Vitis vinifera, drugo, 11460459: Vitis vinifera, drugo : namen testiranja: sum na: Xylosandrus crassiusculusAndreja Kavčič, 2019, expertise, arbitration decision Keywords: varstvo gozdov, Vitis vinifera, žuželke, morfološke analize Published in DiRROS: 10.10.2019; Views: 1776; Downloads: 113 This document has many files! More... |
6. Poročilo o preskusu št.: LVG 2019-014 : opis vzorca: Vitis vinifera, les, lubje, sekanci, št. enot 10 : namen testiranja: sum na: Fitofagna žuželkaAndreja Kavčič, 2019, expertise, arbitration decision Keywords: varstvo gozdov, morfološke analize, Kmetijsko gozdarski zavod Novo mesto, vinska trta, Vitis vinifera, les, fitofagna žuželka, podlubniki, Xylosandrus germanus Published in DiRROS: 12.04.2019; Views: 2356; Downloads: 146 This document has many files! More... |