Sorogen elongation and side branching during fruiting body development in Polysphondylium pallidum.

Abstract

We report a cinematographic analysis of culmination in fruiting bodies of Polysphondylium pallidum. During the final stages of aggregation, sorogen elongation is slow. An increase in the rate of sorogen elongation occurs when the growing stalk contacts the substratum, lifting the cell mass into the air. The elongation process slows and finally stops as differentation of the terminal spore mass occurs. During the rapid elongation phase, variations in the rate of elongation of the main cell mass are correlated with the process of side branching. Side-branch elongation resembles elongation of the main sorogen with the rate of elongation increasing as the side-branch stalk contacts the main stalk and slowing as spore differentiation occurs. The morphological events of branching have been studied in detail and models to explain this process are discussed.