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…

Drought tolerance assessment and differentiation of grapevine cultivars using physiological metrics: insights from field studies

This study aimed to validate a protocol and compare metrics for evaluating drought tolerance in two Vitis vinifera grapevine cultivars under field conditions. Various metrics were calculated to represent the physiological responses of plants to progressive water deficit. Data were collected from Sauvignon Blanc and Chardonnay plants subjected to three irrigation levels during the 2022-2023 season, along with data from three previous seasons. Hydro-escape areas were used to assess the plant’s ability to reduce water potential with decreasing soil water availability.

Effects of different soil types and soil management on greenhouse gas emissions 

Soil is important in the carbon cycle and the dynamics of greenhouse gases (CO2, CH4 and N2O). Key soil characteristics, such as organic matter content, texture, structure, pH and microbial activity, play a determining role in GHG emissions[1]. The objective of the study is to delimit different types of soil, with different soil management and to be able to verify the differences in CO2, CH4 and N2O emissions. The study was carried out in a vineyard of Bodegas Campo Viejo in Logroño (La Rioja), whose plant material is Vitis vinifera L. cv. Tempranillo.

Conventional and alternative pest management strategies: a comparative proteomic study on musts

In a context of sustainable agriculture, “agroecological immunity” is an emerging concept to reduce the use of chemical pesticides to protect crops against pathogens. This alternative strategy aims to combine different levers including the use of “bio”solutions. These include biocontrol products, some of which being plant defense elicitors, as well as products authorized in organic farming such as copper or sulfur. In vineyards, depending on climate conditions, powdery and downy mildews can be devastating diseases.

Exploring the prevalence of esca-induced leaf symptoms in French vineyards and the role of climate: a national scale analysis

Esca, a severe trunk disease affecting vineyards, is caused by fungal pathogens that induce wood necrosis and decay, leaf symptoms, yield losses, and potentially a rapid death of the vine. The prevalence of this disease varies across years, regions, cultivars, and plot ages. Despite its significance in understanding and predicting dieback risk in different vineyards, the role of climate in trunk diseases remains a relatively unexplored research area. While some studies have demonstrated the impact of certain climatic conditions on the prevalence of the disease, they often focus on a limited number of plots and yield conflicting results.We conducted a statistical analysis, using a Bayesian approach on a national database comprising prevalence data of esca from over 500 different plots in France, spanning the years 2003 to 2022 and encompassing various cultivars.

Viticultural heritage in mountain territories of Catalonia: prospecting in the region of Osona, northern Spain

The recovery of ancestral or minority vine varieties has been gaining great interest in recent years, among other reasons because it is likely that some of these varieties, due to the fact that they are found in relict areas, have a greater potential for adaptation to external factors (biotic or abiotic) and can minimize the effects that climate change is causing in viticulture. Varieties that can be grown at altitude are currently being sought to combat rising temperatures and prolonged extreme drought conditions. In Catalonia, the Pyrenean expansion of vineyard cultivation is documented from the 10th century and has been related to the “small climatic optimum” (9th-12th centuries) and also to seigniorial power.[1] But different adverse climatic periods and the arrival of Phylloxera by the late 19th century made many of these crops disappear.[2]