Effect of Tin on Biologic Aspects of Cunninghamella echinulata and Fusarium oxysporum, under Various Cultural Conditions PDF

Keywords

Cunninghamella echinulata, Fusarium oxysporum, Biology,

Abstract

In absence of external carbon source, the loss in weight from 6-day old mycelial felts was greater with Fusarium oxysporum than with Cunninghamella echinulata when supplied with nitrate, though carbon dioxide output was almost similar. Although the three tin compounds seemed to exert no effect on growth of Cunninghamella when supplied with nitrate alone, stannous ions stimulated growth on either urea or peptone media . On the other hand, the three compounds were toxic to Fusarium when supplied with urea. With an adequate supply of carbon, the inorganic tins enhanced, but Plictran inhibited, growth of Cunninghamella. Nitrate favored greater absorption of sugar than either urea or peptone. Stannic and Plictran were suppressive to glucose uptake by Cunninghamella when supplied with either nitrogen sources, whereas stannous exerted almost no effect with nitrate or urea but was suppressive with peptone. The tin compounds also hindered glucose uptake by Fusarium, a phenomenon that was alleviated or even reversed with urea feeding. Inorganic tin stimulated respiration of Cunninghamella in the presence of nitrate, while respiration was inhibited in the presence of urea. Plictran inhibited respiration in media containing either nitrate or urea. On the other hand, the three tin containing compounds enhanced respiration of Fusarium regardless of the nitrogen source. Further, the presence of glucose in media containing tin attenuated respiration of Cunninghamella, regardless of the nitrogen source. The results show that glucose slightly suppressed nitrogen absorption from urea or peptone , but remarkably increased nitrogen uptake from nitrate media. In most cases, the various tin compounds inhibited nitrogen absorption by Cunninghamella when glucose was supplied to the media. In the absence of glucose, the tin compounds stimulated urea and peptone absorption.