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bioRxiv · 10.64898/2026.07.14.738465

Introducing PHJ Media: A Unique Machine Learning -Driven Basal Formulation to Overcome Recalcitrance for Multi-Genotype Micropropagation of Cannabis sativa L.

Abstract

Applications of tissue culture are critical for Cannabis sativa L. (cannabis), supporting clonal propagation, germplasm preservation, pathogen elimination, among other biotechnological applications. However, extensive genetic diversity associated with cannabis results in highly variable responses to in vitro conditioning, and no consensus basal media formulation exists to support reproducible micropropagation across genotypes. To address these limitations, a hybridized ensemble-NSGA-II approach was employed for concurrent optimization of individual media components to create a species specific, cultivar inclusive basal salt formulation for cannabis micropropagation. The resulting PHJ media represents a unique formulation that overcomes recalcitrance across a wide array of cannabis cultivars, facilitating improved growth and uniformity for the nine cultivars used in its development and validation. These results remain consistent from explant initiation through multiple rounds of subculture. The ability of PHJ to overcome genotypic recalcitrance is telling of its potential applicability with an array of plant species beyond cannabis. Additionally, robust performance both with and without plant growth regulators underscores the plausible use of PHJ for diverse applications beyond standard micropropagation. Ultimately, this cultivar-inclusive basal medium demonstrates utility for both scientific research and industrial-scale operations.

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Pepe, M., Hesami, M., Jones, M.. 2026-07-15. Introducing PHJ Media: A Unique Machine Learning -Driven Basal Formulation to Overcome Recalcitrance for Multi-Genotype Micropropagation of Cannabis sativa L.. https://doi.org/10.64898/2026.07.14.738465

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