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…

Towards a better understanding of cultivar susceptibility to esca disease: results from a pluriannual common garden monitoring

Grapevine (Vitis vinifera L.) exhibits a high level of genetic and phenotypic diversity among the approximately 6000 cultivars recorded. This perennial crop is highly vulnerable to numerous fungal diseases, including esca, which is a complex vascular pathology that poses a significant threat to the wine sector, as there is currently no cost-efficient curative method[1]. In this context, an effective approach to mitigate the impact of such diseases is by leveraging the crop’s genetic diversity. Indeed, susceptibility to esca disease appears to vary between cultivars, under artificial or natural infection. However, the mechanisms and varietal characteristics underlying cultivar susceptibility to esca are still unknown.

Understanding the impact of rising temperatures due to climate change on aromatic compositions in Malbec wines from Mendoza, Argentina

Mendoza is one of Argentina’s most important and outstanding wine regions producing the renowned Malbec wines due to its optimal soil and weather conditions. However, the effects of 21st-century climate change would negatively impact Malbec wines quality. This study investigated the effect of temperature increase and the impact of plant hormone abscisic acid (ABA) used to mitigate the negative effect of temperature increase on Malbec wines aromatic composition through GC-MS. Four treatments were applied on vines at field condition: Control, Control + 3 ºC, ABA and ABA + 3 ºC.

Organic mulches slightly influence wine phenolic composition and sensorial properties

Grapevines have traditionally been grown in semi-arid areas, but viticulture is now compromised by climate change. Therefore, it is necessary to implement environmentally friendly viticulture practices to adapt grapevines to current climatic conditions. In this context, organic mulches offer many benefits, such as reduced soil erosion and increased organic matter, soil water content and crop productivity. However, these practices must not compromise grape and wine quality. Therefore, the objective of this study was to evaluate the effect on wine physicochemical and phenolic composition and sensorial properties of different soil management practices on the vine row. Over four years, five soil treatments were examined in two different vineyards.

Bioprotection of grape must by Metschnikowia sp.: genericity and mechanism

The market trend heads to food products with less chemical inputs, including in oenology. During the winemaking process, sulfites are commonly use to avoid microbiological contamination and stabilization of the wine thanks to its antimicrobial and antioxidant activities. Nevertheless, this use is not without consequences on human health and environment, leading for example to allergic reaction and pollution. A biological alternative to these sulfites has emerges: the bioprotection.

Physico-chemical properties of vine pruning residues with potential as enological additive

Grapes are one of the world’s primary fruit crops, and pruning activities generate high amounts of annual wood wastes [1]. These pruning shoots contain valuable phenolic compounds and could have numerous potential applications [1,2]. Consequently, the aim of this work was to evaluate the physico-chemical properties of vine pruning residues with potential as enological additives. For this purpose, grapevine shoots from 12 varieties grown in Chile were collected during the winter of 2021.