Cytoembryological and morphometric characteristics of some Armenian grape cultivars

Research Not

Preliminary study of Armenian grapevines phenolic contents

Research Not

Armenian grapevines: cytoembryological, morphological and chemical analysis

The objectives of our study was to phenotype Armenian grapevines on the base of cytoembryological, morphometric and phenolic content analysis of 10 wine and 10 table cultivars (Vitis vinifera L.). The presented results suggest that Armenian table grape cultivars have higher level of abnormalities in the process of seed formation than wine cultivars. However, during ovule development, the observed differences between table and wine varieties were not significant. The berry morphometric analysis demonstrated that table cultivars formed significantly larger and heavier berries than wine cultivars. The obtained results show that wine grapes contained significantly higher phenol concentrations than table grapes, in both colored and white grapevine cultivars. The study of phenol composition, an important chemical descriptor in grapevine phenotyping, provides oenological information useful to improve the wine quality. Cultivar characterization could be used as marker for the selection of table and wine grape breeding programs. These results will be upgraded in the database for Armenian grapevine varieties. In future Armenian germplasm will be compared with datasets of neighboring countries, to determine the varietal origins relationships

Genetic analysis of the VvMybA1 gene in Armenian grapevines (V. Vinifera L.)

Research Not

Analysis of the origin of parthenocarpy in grapevine cultivar Corinto Bianco

Póster presentado en la 2nd Annual ConferenceFleshy Fruit Development & Ripening (COST Action FA1106 QualityFruit), celebrada en Chania (Grecia) del 22 al 25 de septiembre de 2013.Seedless fruits appear spontaneously in grapevine (Vitis vinifera L.) as a result of somatic variation. Stenospermocarpic and parthenocarpic seedlesness are known. The first type is widely used in table grapes production because seed development aborts after fertilization giving rise to seed traces and almost normal size berries. In contrast, small berries without seed traces develop in absence of fertilization in parthenocarpic cultivars that are appreciated for raisin production. The cultivar Corinto Bianco is a parthenocarpic somatic variant of the Spanish seeded cultivar Pedro Ximénez. Morphological and molecular comparison of flower development and gametogenesis between both genotypes were directed to understand the genetic and molecular basis of this parthenocarpic phenotype. Histological analyses showed that ovules developed similarly in both genotypes. However, macrogametogenesis was altered in Corinto Bianco showing disorders during mitosis after mother cell meiotic reduction. Microgametogenesis was also altered in Corinto Bianco, which pollen was 100% sterile in 2012 and 2013, compared with Pedro Ximénez pollen that showed only 8.47 and 21.64% of sterility in those years. The average number of seeds per berry was 1.35 in Pedro Ximénez berries, which weight was six times higher than in Corinto Bianco parthenocarpic berries with zero seeds. In addition, we observed partial phenotypic reversion in 2.6% of Corinto Bianco berries that carried one seed and displayed a comparable size to that of Pedro Ximénez berries. These seeds were unable to germinate in soil under normal conditions. Fortunately, following an in vitro germination protocol we were able to rescue 41 seedlings derived from revertant berries for further analyses. Gene expression alterations between Pedro Ximénez and Corinto Bianco, that could lead to the identification of candidate genes responsible for the phenotypic change, were analyzed by comparing closed flowers of both genotypes at 50% bloom time using the NimbleGen Vitis HX12 microarray. We identified 441 genes upregulated and 949 downregulated in the parthenocarpic mutant (¿2-fold change and 5% FDR). Interestingly, genes related with cell cycle and gametogenesis were downregulated in Corinto Bianco, including a cyclin (CYB1;2- like) and a MADS-box gene (AGL66-like), whose function in Arabidopsis is related with mitosis and pollen development, respectively. The expression of these genes could be related with defects in gametogenesis in Corinto Bianco. These preliminary results suggest the presence of defects in the meiotic mechanisms central to the process of gametogenesis in Corinto Bianco, providing clues for further characterization of the origin of parthenocarpy in this cultivar.Peer Reviewe

Armenian national grapevine collection: Conservation, characterization and prospects

The general strategy for grapevine genetic resources conservation in Armenia encompasses the collection of the still existing diversity and the use of protection techniques to minimize the losses over time. Being studied mainly by ampelography, the genetic diversity of Armenian grapevine needs to be re-investigated in accordance with modern requirements and international scales. The purpose of the presented research was the first large-scale molecular characterization of Armenian grape varieties by molecular methods using a set of 24 simple sequence repeat (SSR) markers encompassing the nine SSR markers recommended by the European project GrapeGen06. The obtained results indicate the uniqueness of the major part of the investigated varieties and reveal a substantial level of genetic variation within the Armenian grapevine. Based on the realized large-scale investigation a true-to-type inventory of Armenian grape germplasm will be realized and documented in theVitis International Variety Catalogue and in the European Vitisdatabase. The next step having strategic importance in terms of conservation of grape genetic resources in Armenia will be establishment of the first ArmenianVitis database with multi-crop passport description of all varieties preserved in grape collection

Hydrogen-doped Brookite TiO2 Nanobullets Array as a Novel Photoanode for Efficient Solar Water Splitting

As a representative photocatalyst for photoelectrochemical solar water splitting, TiO2 has been intensively studied but most researches have focused on the rutile and anatsase phases because brookite, another important crystalline polymorph of TiO2, rarely exists in nature and is difficult to synthesize. In this work, hydrogen doped brookite (H:brookite) nanobullet arrays were synthesized via a well-designed solution reaction for the first time. H:brookite shows highly improved PEC properties with excellent stability, enhanced photocurrent, and significantly high Faradaic efficiency for overall solar water splitting. To support the experimental data, ab initio density functional theory calculations were also conducted. At the interstitial doping site that has minimum formation energy, the hydrogen atoms act as shallow donors and exist as H+. which has the minimum formation energy among three states of hydrogen (H+. H0, and H-). The calculated density of states of H:brookite shows a narrowed bandgap and an increased electron density compared to the pristine brookite. The combined experimental and theoretical results provide frameworks for the exploration of the PEC properties of doped brookite and extend our knowledge regarding the undiscovered properties of brookite of TiO2.ope

Description of the Vitis vinifera L. phenotypic variability in eno-carpological traits by a Euro-Asiatic collaborative network among ampelographic collections

The grapevine intra-specific variability captured an increasing interest during the last decades, as demonstrated by the number of recently funded European projects focused on the grapevine biodiversity preservation. However, nowadays, crop plants are mainly characterized by genotyping methods. The present work summarizes the phenotype data collected among 20 ampelographic collections spread in 15 countries, covering mostly of the viticultural areas in the Euro-Asiatic range: from Portugal to Armenia and from Cyprus to Luxembourg. Together with agro-climatic characterization of the experimental site, in two years, about 2400 accessions were described, following a common experimental protocol mainly focused on the carpological and oenological traits, obtaining a general overview of the distribution of the considered phenotypic traits in the cultivated Vitis vinifera species. The most replicated cultivars were selected and, for the subset of these reference cultivars, their behavior in the different environmental conditions over sites and years was described by ANOVA methods

Description of the vitis vinifera L. Phenotypic variability in eno-carpological traits by a Euro-Asiatic collaborative network among ampelographic collections

The grapevine intra-specific variability captured an increasing interest during the last decades, as demonstrated by the number of recently funded European projects focused on the grapevine biodiversity preservation. However, nowadays, crop plants are mainly characterized by genotyping methods. The present work summarizes the phenotype data collected among 20 ampelographic collections spread over 15 countries, covering most of the viticultural areas in the Euro-Asiatic region: from Portugal to Armenia and from Cyprus to Luxembourg. Together with agro-climatic characterization of the experimental site, over two years about 2,400 accessions were described. A common experimental protocol mainly focused on the carpological and oe-nological traits was followed, obtaining a general overview of the distribution of the considered phenotypic traits in the cultivated Vitis vinifera species. The most replicated cultivars were selected and, for the subset of these reference cultivars, their behavior in the different environmental conditions over sites and years was described by ANOVA methods