Do Cecidomyiidae galls of Aspidosperma spruceanum (Apocynaceae) fit the pre-established cytological and histochemical patterns?

Abstract

Cecidomyiidae galls commonly present a zonation of tissues with lignified cell layers externally limiting a reserve tissue and internally limiting a specialized nutritive tissue next to the larval chamber. The cytological aspects of this specialized tissue indicate high metabolic activity as well as carbohydrate accumulation. In Aspidosperma spruceanum-Cecidomyiidae gall system, ultrastructural and histochemical investigations corroborated this pattern and also revealed the storage of proteins in the nutritive cells. Reactive oxygen species (ROS), callose, and pectin accumulation were related to the feeding activity of the galling herbivore. Phosphorylase, glucose-6-phosphatase, acid phosphatases, invertases, and sucrose synthase activities were detected for the first time, in the Neotropical region, and discussed in relation to gall maintenance and the feeding activity of the Cecidomyiidae.

Morphological Patterns of a Hymenopteran Gall on the Leaflets of <i>Caryocar brasiliense</i> Camb. (Caryocaraceae)

“…The formation of a suberized covering in galls was already observed in other systems such as Guarea macrophylla subsp. tuberculata (Meliaceae)-Cecidomyiidae [7] and Copaifera langsdorffii (Leguminosae)-Cecidomyiidae [8,18]. The thickness of the cuticle, trichomes neoformation, and the eventual substitution of epidermis for periderm are characters that reinforce the hypothesis of the microenvironment [3,49], which benefits gall inducing herbivores.…”

“…During gall formation, several alterations in epidermis, parenchyma, xylem and phloem cells take place [6]. Also, periderm and new vascular bundles differentiation [7][8][9], cuticle thickness, increase in number of non glandular trichomes, crystals and sclereids appearance, changes in mesophyll cell shapes [7,[10][11][12][13][14], and the formation of a nutritive tissue [7,[15][16][17][18][19] are some of the most common alterations observed during the development of gall structure.…”

The imbalance of redox homeostasis in arthropod-induced plant galls: Mechanisms of stress generation and dissipation

“…This accumulation of ROS occurred in the cells of non-galled tissues, which are the mother cells of the gall parenchymatic cortex in Aspidosperma australe and A. spruceanum [75,76]. Agrawal (2006) suggested that the unbalancing of ROS and antioxidant production is evidence of oxidative stress.…”

“…High concentrations of ROS in gall tissues were detected via the 3.3' diaminobenzidine (DAB) histochemical method in four Neotropical galls [16,52,76,77], and were related to the high oxidative stress generated in response to attack by gall-inducing organisms [79]. This accumulation of ROS occurred in the cells of non-galled tissues, which are the mother cells of the gall parenchymatic cortex in Aspidosperma australe and A. spruceanum [75,76].…”

“…Biochemical and biophysical reactions in these compartments, i.e., the inner side of the plasma membrane and the cell-wall continuum respectively, culminate in the redifferentiation of cells, with a new organization of tissue layers. The establishment of a new redox balance within these two cell compartments involves the accumulation of reactive oxygen species (ROS), as has been demonstrated histochemically, and is related to the determination of new cell fates and functions [16,52,[75][76][77]. In a general sense, the balance between ROS production and ROS scavenging in cellular compartments is assumed to affect the cell redox state, which modulates the cell reprogramming involved in the responses to the biotic stimuli of gall initiation and establishment, or triggers plant-defense mechanisms such as hypersensitivity responses (HR) [79].…”