terclim by ICS banner
IVES 9 IVES Conference Series 9 Functional characterization of grapevine MLO genes to define their roles in Powdery mildew susceptibility by CRISPR/Cas9 genome editing

Functional characterization of grapevine MLO genes to define their roles in Powdery mildew susceptibility by CRISPR/Cas9 genome editing

Abstract

Successful powdery mildew (PM) infection in plants relies on Mildew Resistance Locus O (MLO) genes, which encode susceptibility factors essential for fungal penetration. In Arabidopsis, loss-of-function mutations in three clade-V MLOs, AtMLO2, 6, and 12 confer complete resistance to PM infection. Since then, efforts are on to discover MLO genes contributing to PM susceptibility in many species to introduce mlo-based PM-resistance. Earlier studies in tomato and grapevine, using the RNAi approach, attributed PM susceptibility to SlMLO1, 5, and 8 and VvMLO3, 13, and 17, respectively indicating likely functional redundancy among MLOs. Here, we disrupted the closest grapevine orthologues, VvMLO3, 4, 13, and 17 through CRISPR/Cas9-mediated mutagenesis in the microvine model with the goal of identifying the candidate MLO genes to introduce mlo-based PM resistance. Individual mutants mlo3, mlo4, mlo13 and mlo17 showed 8 to 50% less infection to E. necator, whereas double mutants, mlo3/4, mlo3/13 andmlo13/17 and triple mutant mlo3/13/17 showed 60 to 90% less infection. But the quadruple mlo3/4/13/17 mutant plants showed near complete PM resistance. Considerable differences were observed in the resistance level of clones among the triple and quadruple mutants due to the differences in editing efficiency of individual guide RNAs. Some mutants showed pleiotropic effects in the growth and development, ranging from early senescence and stunted growth to non-flowering phenotypes, which also seemed to depend on the percentage of gene-edited cells in the plant. The overarching goal is to excise the genome-integrated T-DNA cassette from the mutants using CRISPR Ribonucleoproteins for transgene-free PM resistance.

DOI:

Publication date: June 13, 2024

Issue: Open GPB 2024

Type: Article

Authors

Satyanarayana Gouthu1*, Laurent Deluc2,3, Samuel Talbot1

1,2 Department of Horticulture, Oregon State University, Corvallis, OR, USA
3 Oregon Wine Research Institute, Oregon State University, Corvallis, OR, USA

Contact the author*

Keywords

Powdery mildew, Grapevine MLO, mildew-resistance, Gene Editing

Tags

IVES Conference Series | Open GPB | Open GPB 2024

Citation

Related articles…

An overview of geological influences on South African vineyards

The role of soils and bedrock geology has long been acknowledged as a fundamental component of terroir. In South Africa the influence of geology is misunderstood and some important geological components will be highlighted in this paper.

The use of zirconia dioxide enclosed in a metallic cage for the stabilisation of Chardonnay white wine

White wines are commonly stabilised by removing the heat unstable proteins through adsorption by bentonite, an effective but inefficient wine processing step. Alternative absorbents are thus sought and zirconium dioxide (zirconia) is recognised as a promising candidate.

Influence of a spontaneous cover crop on the vineyard and soil erosion under Mediterranean climate

Sixty five % of the agricultural area of the Basque Country located in the DO Ca Rioja corresponds to vineyards. More than 40% of it has an average slope greater than 10%, which makes it sensitive to erosive processes. Furthermore, it is foreseeable that extreme weather events (storms, hail, extreme heat and cold, etc.) will be favored due to climate change. Cover cropping can mitigate this risk, and therefore the objective of this work is to evaluate the impact that a vegetable cover has on the agronomic behavior of the vineyard, the quality of the grape and soil erosion. For this, a trial has been carried out with a Graciano variety vineyard with a slope between 10% -20% during the years 2020 and 2021. Conventional tillage management in the area has been compared (4-6 passes per year of tillage machinery) versus spontaneous vegetation cover management in the vineyard. This implies not tilling and allowing the grass of the land to colonize the range between the lines of vines, controlling their height through 1-3 mowing passes per year, always trying to affect the surface of the land as little as possible. The vegetative growth, yield and quality of the grape and wine was measured. Furthermore, erosion has been measured using Gerlasch boxes. The yield was lower in the second year of the trial in the cover crop treatment, but erosion was significantly reduced.

Impact of malolactic fermentation on volatile composition and sensory properties of white and rosé wine from the greek variety moschofilero

Moschofilero is a native grape variety, classified as a ‘gris’ type variety, that is cultivated in PDO Mantineia, Peloponissos, Greece. It is used for the production of both white and rosé wines. Due to high altitude of the vineyards, the harvest is done by mid October, and many vintages are characterised by high acidities and low pH values.

1H-NMR-based Untargeted Metabolomics to assess the impact of soil type on the chemical composition of Mediterranean red wines

Untargeted metabolomics has proven to be an effective method to study the impact of the terroir on metabolic profile of wines. In this context, the aim of this study was to evaluate the effects of different soil types on the chemical composition of Mediterranean red wines, through 1H-NMR metabolomics combined with chemometrics.Grapes from Nero d’Avola L. red cultivar cultivated on four different soil types were separately vinified to obtain four different red wines.One milliliter of raw wine was analyzed by means of a Bruker Avance II 400 spectrometer operating at 400.15 MHz