Potato microtuberization: its regulation and applications

Potato (Solanum tuberosum L.) is a globally consumed staple food crop grown in temperate regions. The underground storage organs (tubers) are a rich source of carbohydrates, proteins, vitamins, and minerals, contributing to food and nutritional security. Tuberization, the process by which underground stems (stolons) develop into tubers, is intricately regulated by genetic, epigenetic, and environmental factors. Studying the developmental transition from stolon to tuber in soil-based systems is challenging due to the limited visibility of below-ground stages. Microtuberization is the formation of small tubers under controlled, soil-less, and in vitro conditions, offering an effective alternative for precise monitoring of tuber development stages. Microtubers are valuable as disease-free seed propagules and essential for germplasm conservation, supporting the preservation and propagation of genetic resources. Microtuberization is influenced by both internal factors, viz., genotype and explant, and external factors, viz., photoperiod, temperature, light, plant growth regulators, sucrose, and synthetic molecules. These factors collectively regulate the transition from stolon to tuber. Microtubers exhibit strong similarities to field-grown tubers, making them a reliable model to study the environmental and molecular mechanisms of tuberization. This review examines the key factors driving microtuberization and explores potential molecular regulators involved in stolon-to-tuber transition. Furthermore, the applications of microtuberization are highlighted, including disease-free seed production, mass multiplication, germplasm evaluation and conservation, molecular farming, genetic engineering, and stress adaptation research. Additionally, microtubers serve as an experimental tool for unraveling the molecular intricacies of tuberization, paving the way for advancements in potato research and global food security strategies.