Advances in Biology & Earth Sciences

The ecological-anatomical characteristics of vegetative and generative organs of Althaea officinalis L. ecotypes were examined. Microscopic analyses involved comparative assessment of transverse sections from samples collected under in situ and ex situ conditions, where statistically significant structural differences were identified. In situ specimens showed denser tissue organization, intensive accumulation of ergastic substances, well-developed sclerenchyma and palisade parenchyma, as well as a higher density of secretory structures and trichomes. In contrast, ex situ specimens exhibited hypertrophy and hyperplasia in vegetative organs, resulting in enlarged parenchymatous tissues and xylem vessels with greater diameters. Functional activity of stomatal apertures was also observed. The results indicated enhanced development of anatomo-functional structures and formation of intracellular inclusions under in situ conditions. Differences in the stomatal apparatus - small guard cells with closed stomata in situ (xerophytic trait) versus large guard cells with open stomata ex situ (mesophytic trait) - demonstrate the species’ phenotypic plasticity and adaptive strategies. This ecological-anatomical comparison, conducted for the first time within the flora of Azerbaijan, provides a valuable scientific basis for understanding the anatomical foundations of ecological adaptation in medicinal plants.