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…

Yield prediction assessment before bloom and at veraison in a cv. Airén high yielding vineyard in Toledo (La Mancha, Spain)

Anticipation in the possible responses of grapevines to environmental variations is key to adjust field work in view of a more effective management. This idea has been the driving force behind the current work, which seeks to understand the interaction patterns of the vine with its habitat throughout the growing cycle.

USING CHECK-ALL-THAT-APPLY (CATA) TO CATEGORIZE WINES: A DECISION-MAKING TOOL FOR WINE SELECTION

Bordeaux is the largest appellation vineyard in France. This contrasting vineyard with varied terroirs offers all styles of wine, resulting from the blending of several grape varieties. If these different profiles make the renown of Bordeaux wines, it can appear as a constraint when the aim is to study Bordeaux wines in their diversity. The selection of a representative sample can be performed by a sensory analysis carried out by trained panelists or by wine professionals, which can take several forms: consensus among experts, conventional descriptive analysis, typicality or quality evaluation. However, because of time, economic, and logistical constraints, these methods have limited applications. As an alternative to classical descriptive analysis, more intuitive methods that do not require training have been proposed recently to describe wines using an expert panel such as Napping, Free Choice or Flash Profiling, CATA or RATA.

Influence of the carbonic maceration winemaking method on the colour features of Tempranillo red wines

During recent years, carbonic maceration (CM) wines are increasingly demanded by consumers. The Spanish Rioja Qualified Designation of Origin (D.O.Ca. Rioja) is a winemaking area

EFFECT OF FERMENTATION TEMPERATURE GRADIENT AND SKIN CONTACT ON ESTER AND THIOL PRODUCTION AND TROPICAL FRUIT PERCEPTION IN CHARDONNAY WINES

Wines with tropical fruit aromas have become increasingly more available1,2. With increased availability of different wine styles, it has become important to understand the compounds that cause the fruity aromas in wine. Previous work using micro fermentations showed that fermentation temperature gradients and time on skins resulted in an increase in thiol and ester compounds post fermentation and these compounds are known to cause tropical fruit aroma in wines³. This work aimed to scale up these fermentations/operations to determine if the desired aromas could still be achieved and if there is a perceivable difference in tropical fruit aromas, liking, and emotional response in the wines at the consumer level.

Alternative methods to evaluate the pinking susceptibility of white wines: derivative spectroscopy and ciel*a*b* colour analysis

Pinking describes the appearance of a salmon-red blush in white bottled wines produced exclusively from white grape varieties. It is understood as an undesirable chromatic phenomenon by both wine consumers and the industry. Nowadays, there are no treatments to fully reverse pinking once it occurs. Partial reversion has been shown after exposure of pinked wine to ultraviolet (UV) light.