A study on Tribulus terrestris L. anatomy and ecological adaptation

Abstract

A study on Tribulus terrestris root, stem and leaf anatomy in implication for its ecological adaptation was conducted. The anatomical structure of the leaf showed clearly distinguished xeromorphic adaptations typical for C4 plants. The lamina is isobilateral and amphistomatous and possesses thick cuticle, "Kranz" anatomical structure, mesophyll with reduced intercellular spaces, epidermis with small stomata and reduced stomatal density and numerous unicellular trichomes particularly on the lower epidermis. The leaf structure explains the plant's poor performance when shaded and limits its distribution to sunny locations. The stem and root have compact structure with well developed vascular tissue, high sclerification and little parenchyma. The small intercellular spaces make roots and stems not well aerated and explain the poor growth of Tribulus terrestris plants on waterlogged soils.