Utilization of nutritional compounds and sclerotial development of Sclerotium rolfsii isolated from Elaeis guineensis and Xanthosoma mafaffa in Ghana

2008

English

Sclerotium rolfsii is a facultative soil parasite of economic importance causing disease of several eco­nomic crop plants. Bacterial and fungal parasites are themselves an assemblage of strains differing genetically and liable to variation. The possible effect of external nutrients 011 different S. rolfsii strains in Ghana has not been studied. In this study the utilization of twelve different nutritional compounds and sclerotia formation by jive strains of Sclerotium rolfsii, SrXLL, SrXAJ, SrXA2, SrELJ and SrEL2 was investigated. In broth media with different carbon compounds - fructose, glucose, maltose, starch and sucrose - and with different nitrogen compounds - Ammonium chloride, Ammonium nitrate, As­paragi11e, Pepto11e and Sodium nitrate - a clearly discernible order of ability to utilize the hvo groups of compounds was noticed. The order of the strains in descending order of efficiency was SrEL2 > Sr ELI SrXLL > SrX'4l > SrXA2. Among the carbon compounds the least utilized was starch. The best car­bon compound varied with the strains. Pepto11e was universally a good nitrogen source. Over a co11-ce11tratio11 range of 0.5 to 2.0%, the greatest amount of pectolytic enzymes was produced in pectin me­dia (20.0 per minute), Filtrates of strains SrXLL, SrXAJ and SrEL2 showed greater pectolytic enzymes activity than those of strains SrXA2 and SrELJ. But strains SrXAJ and SrXA2 showed greater ability to break down cellulose than the other three strains. In all the media studied the pH of the culture filtrate decreased to acidic levels at the end of incubation period.

Tortoe, C.; Clerk, G. C.