Anatomia e histoquímica de galhas foliares em Cnidoscolus pubescens Pohl (Euphorbiaceae)

Abstract

Galls are structures that exemplify the complex interaction between plants and insects, both by the methods of defense of the plant against herbivory, and by the attributes developed by insects to take control of the plant and form the chambers of nutrition and maturation. The present work aims at the anatomical and histochemical description of leaf galls in Cnidoscolus pubescens Pohl (EUPHORBIACEAE), which does not have gall records in the literature. In this way, the results contribute for the first time with information about the presence of galls and the processes of their formation in this species. The samples were collected in the city of Santa Teresinha-Ba, stored in fixers for later formation of histological slides, which were analyzed for anatomy, while histochemistry was performed from the submission of samples to different histochemical tests. The anatomy results showed a preference for the galling organism for areas close to or on the central rib, with a certain degree of reorganization of conductive vessels and deformations in other plant tissues. Structures related to the plant's direct defense line were also recorded, with higher concentrations close to gall formation areas. The histochemical results indicated the presence of phenolic compounds and signaled nutritional substances in the free form and contained in other structures, such as free lipids and found within the laticiferous and idioblast and proteins only observed inside the laticiferous. The starch gradient found is related to the plant storage tissue, providing energy for the development of the gall.