FINE STRUCTURE OF THE AGARICUS CARPOPHORE

Abstract

The fine structure in the carpophore of the mushroom, Agaricus campestris, was studied with the electron microscope. The stipe consists of two types of cells (i) fundamental and (ii) long and thread-like. The pileus contains only the first type. The tramal cells of the gills are more elongated than broad, regularly arranged, and rich in cytoplasmic contents. The cross wall of the hyphal cells shows a conspicuous pore apparatus with dark septal swellings encased in the plasma membrane. The nuclear membranes are differentiated early during nuclear division and are highly alveolated around the interphase nucleus. In the maturing basidium, the mitochondria increase in number by division of pre-existing ones, and thus become small with few cristae. Numerous vacuoles appear in the upper portion of the basidium. Oil globules are also produced in the mature basidium but were not observed during the early stages of development of the basidium or in any other part of the carpophore. The young basidium has food reserve which is granular in nature. The basidiospore contains numerous large oil globules, few mitochondria, scanty endoplasmic reticulum, and a wall of three well-defined layers.