terclim by ICS banner
IVES 9 IVES Conference Series 9 Reduced bunch compactness in a clone of Tempranillo associates with a complex reciprocal translocation detected by long-read sequencing genomics

Reduced bunch compactness in a clone of Tempranillo associates with a complex reciprocal translocation detected by long-read sequencing genomics

Abstract

Grapevine cultivars are vegetatively propagated to maintain their varietal attributes. However, spontaneous somatic variation emerges during prolonged periods of vegetative growth, providing an opportunity for the natural improvement of traditional grapevine cultivars. Notably, reduction in bunch compactness is a favorable trait in viticulture, offering advantages such as decreased susceptibility to bunch fungal diseases, and a more uniform ripening of berries. To unravel the genetic and developmental mechanisms behind bunch compactness variation, we examined a somatic variant of Tempranillo Tinto cultivar with loose bunches. We found that the mutant clone exhibits a ~50% reduction in pollen viability compared to typical Tempranillo clones. By aligning Illumina and Nanopore whole-genome sequencing reads to a diploid genome assembly of Tempranillo, we identified genome structural variations (SV) specific of this clone: translocation events involving chromosomes 1-3, 7-11, and 8-17. The presence of the SV breakpoints was validated using PCR and Sanger sequencing. The analysis of self-cross progeny of the mutant clone showed that low pollen viability and reduced number of seeds per berry co-segregate with the SV event between specific haplotypes of chromosomes 1 and 3, suggesting a causal effect for this rearrangement. Inspection of Nanopore read alignments identified that the SV 1-3 event corresponds to a complex reciprocal translocation with duplications at the breakpoints of the two involved chromosomes. Considering that heterozygous reciprocal translocations associate with partially incompatible chromosome pairing during meiosis, we propose that this type of SV decreases fruit set rate by lowering gamete viability, ultimately reducing bunch compactness.

DOI:

Publication date: June 14, 2024

Issue: Open GPB 2024

Type: Article

Authors

Pablo Carbonell-Bejerano1*, Noelia Alañón1, Yolanda Ferradás1,2, Nuria Mauri1,3, José Miguel Martínez-Zapater1, Javier Ibáñez1*

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 Centre for Research in Agricultural Genomics (CSIC-IRTA-UAB-UB), Cerdanyola del Vallès, Barcelona, Spain

Contact the author*

Keywords

bunch compactness, clonal variation, genome structural variation, pollen viability, reciprocal translocation

Tags

IVES Conference Series | Open GPB | Open GPB 2024

Citation

Related articles…

Analysis of off flavours in grapes infected with the fungal bunch rot pathogens, Aspergillus, Botrytis and Pencillium

Fungal bunch rots of grapes cause major losses to grape yield worldwide, yet the impact these moulds have on grape and wine quality is not well characterised. We sought to investigate the formation of unwanted volatile compounds of fungal origin in both synthetic grape juice culture media and in inoculated grape berries. Botrytis cinerea, Aspergillus niger, Aspergillus carbonarius, or Pencillium expansum were grown in synthetic grape juice medium and the culture homogenates analysed 4 and 7 days post inoculation. HS-SPME-GC-MS analysis of the culture homogenates 4 days post inoculation demonstrated that each of the fungi examined produced varying quantities of the mushroom or fungus-like aroma compounds, 1-Octen-3-ol, 1-Octen-3-one and 3-Octanone with A. carbonarius producing up to ten times the amounts of all three metabolites per mg of dry mycelium.

Sensory profile of wines obtained from disease-resistant varieties in La Rioja

The European wine industry is facing multiple challenges derived from climate change and the pressure of different fungal diseases that are compromising the production of traditional varieties. A sustainable alternative maybe the adoption of resistant varieties.
In this study, we have evaluated the enological potential of 9 resistant varieties (5 white and 4 red varieties) in La Rioja. Microvinifications were carried out with three biological replications. Oenological parameters were very diverse with acid content varying from 2.6 g/L to 6.6 g/L.

Survey reveals training needs for airblast sprayer operators

In California, little training in sprayer calibration or pesticide drift management is required to apply pesticides. Yet, there is a need to maximize pesticide efficacy and minimize drift. Therefore, our team is developing a training course on airblast application best practices. We distributed a survey to identify current practices and used importance-performance analysis to interpret responses to the importance of spray related topics and satisfaction with previous training.

Developing and assessing different cordon establishment techniques for long-term vineyard management

Aim: The aim of this research is to quantify the impacts of different cordon establishment techniques on vine health and longevity. It is hypothesised that wrapping developing cordon arms tightly around the cordon wire will cause a constriction of the vascular system, becoming worse over time and disrupting the flow of water and nutrients.

The effect of sulfur compounds on the formation of varietal thiols in Sauvignon Blanc and Istrian Malvasia wines

Varietal thiols 3-sulfanylhexan-1-ol (3SH), 3-sulfanylhexyl acetate (3SHA) and 4-methyl-4-sulfanylpentan-2-one (4SMP) are essential for fruity aromas of Sauvignon Blanc wines. The concentration of varietal thiols in wines was thought to be related to the concentration of their precursors in grapes, however only a small proportion of precursors are released to varietal thiols during fermentation. New findings suggested that specific grape juice metabolites could significantly impact on the development of three major varietal thiols and other aroma compounds of Sauvignon Blanc wines.