Dataset Information

Cluster thinning effect on Pinot noir berry ripening.

ABSTRACT: The impact of yield on fruit and wine quality has been studied extensively; vine response to increased yield is well known, but responsible mechanisms – including the regulation of pathways responsible for color, aroma and mouthfeel – have not been characterized at the level of genetic regulation. To examine the impact of crop load on transcriptomic and metabolomic changes during grape berry maturation vines from two cluster thinning treatments (50% or 75% of clusters removed following fruit set) were compared to control vines (no cluster thinning). Treatments were applied to mature Pinot noir grapevines over three consecutive vintages. Agronomic parameters, including yield per vine and the yield to pruning weight ratio, as well as fruit and wine composition, were determined at harvest. Fruit transcriptomic and metabolomic changes were measured in berry samples collected from each treatment at 7 to 10 day intervals from fruit set to harvest. The patterns of berry development by weight, sugar accumulation, and malic acid degradation indicated that vines responded differentially to crop load reduction by accelerating berry maturation progress. RNA-Seq analysis, and untargeted GC-MS and UHPLC-QTOF-MS -based metabolomic approaches were used. The indication of the acceleration of maturation transcriptional programs and of metabolite accumulation in the treated vines was suggested by multivariate analyses. To identify the transcriptional key triggers of this response we applied a two-regression step statistical approach which identified genes modulated over development dependent on the crop load. Comparing vintages we were able to estimate the environmental influence on the crop load treatments among years. The application of this multifaceted approach allowed the construction of robust models describing the impact of crop load on the genetic regulation of grape maturation.

ORGANISM(S): Vitis vinifera

PROVIDER: GSE101532 | GEO | 2022/12/31

REPOSITORIES: GEO

ACCESS DATA

Similar Datasets

Project description:Leaf removal is a grapevine canopy management technique widely used to modify the source-sink balance and/or microclimate around berry clusters to optimize fruit composition. In general, the removal of basal leaves before flowering reduces fruit set, hence achieving looser clusters, and improves grape composition since yield is generally curtailed more than proportionally to leaf area itself. Albeit responses to this practice seem quite consistent, overall vine performance is affected by genotype, environmental conditions, and severity of treatment. The physiological responses of grape varieties to defoliation practices have been widely investigated, and just recently a whole genome transcriptomic approach was exploited showing an extensive transcriptome rearrangement in berries defoliated before flowering. Nevertheless, the extent to which these transcriptomic reactions could be manifested by different genotypes and growing environments is entirely unexplored. To highlight general responses to defoliation vs. different locations, we analyzed the transcriptome of cv. Sangiovese berries sampled at four development stages from pre-flowering defoliated vines in two different geographical areas of Italy. We obtained and validated five markers of the early defoliation treatment in Sangiovese, an ATP-binding cassette transporter, an auxin response factor, a cinnamyl alcohol dehydrogenase, a flavonoid 3-O-glucosyltransferase and an indole-3-acetate beta-glucosyltransferase. Candidate molecular markers were also obtained in another three grapevine genotypes (Nero d'Avola, Ortrugo, and Ciliegiolo), subjected to the same level of selective pre-flowering defoliation (PFD) over two consecutive years in their different areas of cultivation. The flavonol synthase was identified as a marker in the pre-veraison phase, the jasmonate methyltransferase during the transition phase and the abscisic acid receptor PYL4 in the ripening phase. The characterization of transcriptome changes in Sangiovese berry after PFD highlights, on one hand, the stronger effect of environment than treatment on the whole berry transcriptome rearrangement during development and, on the other, expands existing knowledge of the main molecular and biochemical modifications occurring in defoliated vines. Moreover, the identification of candidate genes associated with PFD in different genotypes and environments provides new insights into the applicability and repeatability of this crop practice, as well as its possible agricultural and qualitative outcomes across genetic and environmental variability.

Project description:Background: Global climate change, in particular the entailed predicted temperature increase, will noticeably affect plants vegetative and reproductive development. High temperatures alter the composition of the grapevine fruit, one of the most important fruits produced worldwide. This is leading to variable yield and quality, already observed in many growing regions in recent years. However, physiological processes underlying temperature response and tolerance of the grapevine fruit have hardly been investigated. Currently, all studies on fleshy fruits investigating their abiotic stress response on a molecular level were conducted during the day but possible night-specific variations were overlooked. The present study explores the grapevine fruit transcriptomic response at different developmental stages upon heat stress at day and night. Methodology/Principal Results: Short heat stresses (2 h) were applied at day and night to vines bearing clusters sequentially ordered according to the developmental stages along their vertical axis. The recently proposed microvine model was grown in climatic chambers in order to circumvent common constraints and biases introduced in field experiments with perennial vines. Post-véraison berry heterogeneity inside clusters was evaded upon constituting homogenous batches following organic acid and sugar measurements on individual berries. A whole genome transcriptomic approach was subsequently conducted using NimbelGen® 090918 12X microarrays (30K). Results revealed important differences in heat stress responsive pathways according to day or night treatment, in particular regarding genes within phenylpropanoid metabolism. Precise distinction of post-véraison stages led to a stage-specific detection of anthocyanin-related transcripts repressed by heat. Important modifications in cell wall-related processes as well as indications for a heat-induced delay of ripening and sugar accumulation were observed at véraison and reversed in later stages. Conclusion: This first day - night study on heat stress adaption of the grapevine berry shows that the transcriptome of fleshy fruits is differentially affected by abiotic stress at night. The present results emphasize the necessity to include different developmental stages and especially different time points in transcriptomic studies. A total of 12 samples were analyzed representing three berry developmental stages (two after the onset of ripening, one during green growth). At each stage, heat stress was applied at day and night. Controls and treated berry samples were drawn in triplicates (two in duplicates) at day and at night on the microvine dwarf (Dwarf Rapid Cycling and Continous Flowering; DRCF) gibberellin-insensitive (GAI) mutant.

Dataset Information

Cluster thinning effect on Pinot noir berry ripening.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure