terclim by ICS banner
IVES 9 IVES Conference Series 9 International Congress on Grapevine and Wine Sciences 9 2ICGWS-2023 9 Identification of a stable epi-allele associated with flower development and low bunch compactness in a somatic variant of Tempranillo Tinto

Identification of a stable epi-allele associated with flower development and low bunch compactness in a somatic variant of Tempranillo Tinto

Abstract

Grapevine cultivars are vegetatively propagated to preserve their varietal characteristics. However, spontaneous somatic variations that occur and are maintained during cycles of vegetative growth offer opportunities for the natural improvement of traditional grape cultivars. One advantageous trait for winegrowing is reduced bunch compactness, which decreases the susceptibility to pests and fungal diseases and favor an even berry ripening. In this study, we examined a loose bunch somatic variant of Tempranillo Tinto cultivar (TT) to elucidate the molecular basis underlying this variation. The variant displayed a masculinized flower phenotype, characterized by an underdeveloped yet functional gynoecium, with reduced development of the style, stigma and septum, as compared to the complete hermaphroditic flowers typically observed in TT. Genetic analysis of its self-progeny demonstrated the co-segregation of the masculinized flower phenotype with the hermaphrodite allele of the grape sex locus (SDR)[1]. While genome re-sequencing did not identify any genetic variation within the SDR locus, an RNA-seq analysis identified one SDR-located gene over-expressed in the somatic variant compared to a control TT clone. The hermaphrodite allele was specifically over-expressed in the variant. Both Illumina WGBS and Nanopore epigenomic analyses identified a hermaphrodite allele-specific hyper-methylated region upstream of the upregulated gene. Analysis of chromatin conformation capture (3C) revealed a three-dimensional rearrangement of the locus, including the presence of a novel 36 kb chromatin loop delimiting the hyper-methylated region, which could be responsible for the over-expression and the phenotype. These findings indicate that somatic epi-alleles in the SDR locus can determine variation in gynoecium development leading to decreased fruit set and looser bunches in grapevine.

Acknowledgements: This study is part of the projects BIO-2017-86375-R and PID2020-120183RB-I00, and PRE-2018-086017 grant funded by MCIN/AEI/10.13039/501100011033 and by “ERDF A way of making Europe”. This study is also part of the vWISE project.

1)  Massonnet, M., Cochetel, N., Minio, A., Vondras, A. M., Lin, J., Muyle, A., Garcia, J. F., Zhou, Y., Delledonne, M., Riaz, S., Figueroa-Balderas, R., Gaut, B. S., & Cantu, D. (2020). The genetic basis of sex determination in grapes. Nature Communications, 11(1), 1–12. DOI: 10.1038/s41467-020-16700-z

DOI:

Publication date: October 4, 2023

Issue: ICGWS 2023

Type: Article

Authors

Alañón, Noelia1*; Ferradás, Yolanda2; Lijavetzky, Diego3; Ferrero, Lucía4; Martínez-Zapater, José Miguel1; Ariel, Federico4; Carbonell-Bejerano, Pablo1; Ibáñez, Javier1

1 Instituto de Ciencias de la Vid y del Vino (ICVV, CSIC-CAR-UR), Departamento de Viticultura, Logroño, Spain
2 Departamento de Biología Funcional, Universidad de Santiago de Compostela, Santiago de Compostela, Spain
3 Instituto de Biología Agrícola de Mendoza (IBAM), CONICET, FCA-UNCuyo, Almirante Brown 500, M5528AHB, Chacras de Coria, Mendoza, Argentina
4 Instituto de Agrobiotecnología del Litoral, CONICET, Universidad Nacional del Litoral, Colectora Ruta Nacional 168km 0, 3000, Santa Fe, Argentina

Contact the author*

Keywords

bunch compactness, somatic variation, flower development, chromatin conformation, epiallele

Tags

2ICGWS | ICGWS | ICGWS 2023 | IVES Conference Series

Citation

Related articles…

INTEGRAPE guidelines and tools: an effort of COST Action CA17111

INTEGRAPE was a European interdisciplinary network for “data integration to maximize the power of omics for grapevine improvement” (CA17111, https://integrape.eu/), funded by the European COST Association from September 2018 to 2022. This Action successfully developed guidelines and tools for data management and promoted the best practices in grapevine omics studies with a holistic future vision of: “Imagine having all data on grapevine accessible in a single place”.

Water availability at budbreak time in vineyards that are deficitary irrigated during the summer: Effect on must volatile composition


In recent years, Mediterranean regions are being affected by marked climate changes, primarily characterized by reduced precipitation, greater concurrence of temperature extremes and drought during the growing season, and increased inter-annual variability in temperatures and rainfall. Generally, high-quality red wines need moderate water deficit. Hence, irrigation may be needed to avoid severe vine water stress occurring in some vintages and soils with low holding capacity. The aim of this work was to evaluate the effects of soil recharge irrigation in pre-sprouting and summer irrigation every week (30 % ETO) from the pea size state until the end of ripening (RP) compared to exclusively summer irrigation every week (R) in the same way that RP, on must volatile composition at harvest.

Effect of two water deficit regimes on the agronomic response of 12 grapevine varieties cultivated in a semi-arid climate

The Mediterranean basin is one of the most vulnerable regions to Climate Change effects. According to unanimous forecasts, the vineyards of Castilla-La Mancha will be among the most adversely affected by rising temperatures and water scarcity during the vine’s vegetative period. One potential strategy to mitigate the negative impacts of these changes involves the identification of grapevine varieties with superior water use efficiency, while ensuring satisfactory yields and grape quality.

Grapevine adaptation to drought and resistance to Neofusicoccum parvum, causal agent of Botryosphaeria dieback

The sustainability of viticulture in response to climate change has been addressed mainly considering agronomic impacts, such as water management and diseases, either separately or together.
In grapevines, there is strong evidence that different genotypes respond differently to biotic and abiotic stresses. A screening was conducted on various local cultivars in response to drought and Neofusicoum parvum infection aiming to evaluate their susceptibility to abiotic stress and resistance to fungal diseases.

Effect of rising atmospheric CO2 levels on grapevine yield and composition by the middle of the 21st century: what can we learn from the VineyardFACE?

Atmospheric CO2 levels have been rising continuously since the industrial revolution, affecting crop physiology, yield and quality of harvest products, and grapevine is no exception [1]. Most of previously reported studies used potted plants in controlled environments, and explored grapevine response to relatively high CO2 levels, 700 ppm or more. The vineyardFACE, established in Geisenheim in 2012, uses a free air carbon dioxide enrichment (FACE) system to simulate a moderate (ambient +20%) increase in atmospheric CO2 in a vineyard planted with cvs. Cabernet-Sauvignon and Riesling grafted on rootstock 161-49 Couderc and SO4, respectively.