COMPARATIVE PHENOMICS IN Limnospira platensis STRAINS REVEALS PHOTOBIOENERGETIC SIMILARITIES AND DIFFERENCES IN AMERICAN AND AFRICAN STRAINS

Abstract

This study addresses the functional diversity of wild Limnospira platensis strains from two continents. Wild strains retain regulatory and metabolic flexibility often lost during domestication, making them essential for exploring natural adaptation within the species evolutionary history. We investigated the comparative growth performance of five Limnospira strains under controlled temperature and light regimes to identify phenotypic differences attributable to single environmental variables. We then evaluated their biochemical and biophysical responses under naturally fluctuating light conditions, linking energy use strategies to phylogenetic relationships. Our analyses reveal that while certain traits, such as fine-tuning of photosynthetic reactions, are shared among closely related strains, overall growth performance is highly variable even within phylogenetically similar groups. For example, photosensitive strains (e.g., UTEX 3086) differ markedly from high light tolerant strains (e.g., UTEX LB 2342) in their mechanisms of coping with light stress. Together, these comparative analyses highlight how environmental sensitivity and energy-use strategies vary across strains of the same species, reflecting broader patterns of diversification within Limnospira.