Leaf anatomy of predominant species in forests and grasslands of the Iberá

Abstract

The Iberá macrosystem has several types of vegetation, where in addition to aquatic and marsh vegetation are found hydrophilic forests, savannahs with a predominance of grasses and grasslands with shrub species interspersed among the herbaceous species. Previous studies of leaf anatomy were only carried out on aquatic and marsh plants. In this work, leaf anatomy was studied in predominant or frequent species growing in grasslands and forests of the Iberá macrosystem, with the aim of detecting leaf structural characters that may represent adaptive value to these environments. Leaves of 42 species corresponding to 26 families were analyzed with optical and scanning electron microscopy. Statistical analysis was performed based on a data matrix of the anatomical characters analyzed, also including the environment types in which the species studied grow. The analyzed characters of the epidermis were: cuticle design, stomata, trichomes, design of epidermal cells of both epidermis, where a predominance of identical morphology on both sides was observed. In the mesophyll, the type, presence and form of calcium and inulin crystals, and distribution of glandular structures such as laticifers, cavities and secretory cells were evaluated. The data reported are discussed in relation to the available literature. No constant characters associated with a particular vegetation type are found. Species living in the same environment do not have similar anatomical features, as shown by clustering analysis (UPGMA).