Challenges and suggestions for tissue culture-free transformation and genome editing in de novo grapevine meristems

Authors: KAYA, HILAL BETUL - Cornell University; Nasti, Ryan; WANG, LI - Cornell University; INOUE, AIDAN - School Of Integrative Plant Science, Cornell Agritech; ORAVEC, MADELINE - School Of Integrative Plant Science, Cornell Agritech; Cadle Davidson, Lance; BOGDANOVE, ADAM - Cornell University

Submitted to: PhytoFrontiers
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 2/6/2026
Publication Date: 2/9/2026
Citation: Kaya, H., Nasti, R.A., Wang, L., Inoue, A., Oravec, M., Cadle Davidson, L.E., Bogdanove, A. 2026. Challenges and suggestions for tissue culture-free transformation and genome editing in de novo grapevine meristems. PhytoFrontiers. 1(1):1-22. https://doi.org/10.1094/PHYTOFR-01-26-0001-SC.
DOI: https://doi.org/10.1094/PHYTOFR-01-26-0001-SC

Interpretive Summary: Generating new engineered plant varieties is challenging especially in woody crops like grapes. New technologies using genes that control how plants grow can be applied along with genetic engineering components to make this process easier, specifically by creating new, modified shoots directly on the treated plant. This strategy has been applied in a variety of species, including tobacco, soybean, and tomato but has been shown with limited success in woody plants. We report our results and challenges getting these modified shoot induction methods to function in grapevines as well as identifying potential avenues for improvement to these techniques based on our observations. In particular, we show that woody plants have challenges with scarring over at the treatment sites limiting the amount of engineered shoots that can form from those sites.

Technical Abstract: Creating new plant varieties typically requires complex laboratory tissue culture to grow whole plants from explant tissues treated with genome engineering components. This is a process that is slow, expensive, and often more challenging in woody crops like grapevine. To bypass this, advancements have been made with "tissue culture-free" methods using growth-stimulating genes to induce new, genetically modified shoots to grow directly on soil-grown plants. This posed as a promising avenue to enable easier and more efficient genetic modification in grapevines. We therefore looked to adapt these methods for soil-grown grapes. Despite over 1,500 attempts across two independent labs using various techniques, no modified shoots were successfully produced with these techniques. The study found that in grapevine, scarring and growth from axillary meristems likely limited the number of new shoots from forming from the treatment sites. Sharing such limiting parameters from these unsuccessful results helps other scientists avoid repeating these same challenges while providing a roadmap for improving future gene-editing methods in challenging to transform crops, particularly woody crops.