Enhanced Biochemical Compounds and Biomarkers Associated from Induced Somatic Embryogenesis in Gossypium Hirsutum L., CV Y331 BLT

Aims: The aim of this work was to identify biomarkers associated with somatic embryogenesis. Study Design: The experiment was laid down in a completely randomized design consisting of two type of calli and each replicated three times. Place and Duration of Study: Department of Nature sciences (Nangui Abrogoua University-Côte d’Ivoire) and Laboratory of Mycology and Plant Biotechnology, Faculty of Pharmaceutical Sciences, GESVAB, EA 3675, University of Bordeaux 2, France, between September 2023 and May 2024. Methodology: To achieve this, cotton calli were induced from hypocotyl explants and cultured under conditions favoring somatic embryogenesis. Then, total phenolics, proteins, and total sugars were quantified in these calli, along with the activity of specific enzyme proteins. Additionally, Ultra-high-performance liquid chromatography (UHPLC) was used to profile polyphenolic compounds. Results: Results indicate that embryogenic calli accumulate significantly higher levels of total phenolics (144.22 µg/g fresh calli), proteins (103.47 µg/g fresh calli), and sugars (15.54 µg/g fresh calli) compared to non-embryogenic calli. Ultra-High-Performance Liquid Chromatography (UHPLC) analysis revealed that embryogenic calli specifically accumulate salicylic acid and catechin, suggesting their role as biochemical markers of somatic embryogenesis. In contrast, non-embryogenic calli were characterized by high rutin and genistein content, indicating their involvement in callogenesis rather than embryogenesis. Enzymatic assays showed increased activity of polyphenol oxidase (PPO), phenylalanine ammonia-lyase (PAL), and tyrosine ammonia-lyase (TAL) in embryogenic calli, underscoring the involvement of phenolic metabolism in embryogenic competence. Additionally, enhanced catalase and ascorbate peroxidase activities in embryogenic calli suggest a critical role in oxidative stress regulation during somatic embryogenesis. Conclusion: These findings provide valuable biochemical markers for selecting embryogenic cotton varieties and optimizing tissue culture protocols. The elevated biochemical synthesis in embryogenic calli enhances metabolic activity, stress tolerance, and developmental signaling, all crucial for successful somatic embryogenesis. This metabolic vigor supports efficient embryo formation and improves regeneration outcomes in cotton biotechnology.