HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Similar articles in this journal Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via Google Scholar Google Scholar Articles by Davey, C. B. Articles by Papavizas, G. C. Search for Related Content PubMed Articles by Davey, C. B. Articles by Papavizas, G. C. Agricola Articles by Davey, C. B. Articles by Papavizas, G. C.

Saprophytic Activity of Rhizoctonia as Affected by the Carbon-Nitrogen Balance of Certain Organic Soil Amendments¹

ABSTRACT

Carbon (C) from cellulose added to soil slightly suppressed the competitive saprophytic activity of Rhizoctonia, whereas nitrogen (N) from NH₄NO₃ increased it. Cellulose and NH₄NO₃, combined to produce a wide range of C/N ratios and incorporated in soil, suppressed Rhizoctonia activity at most C/N ratios. With certain exceptions, soil bacteria and fungi increased in numbers with decreasing C/N ratios. Soil streptomycetes were not greatly affected. Oat straw and soybean hay enriched with NH₄NO₃suppressed Rhizoctonia activity at all C/N ratios tested. The cellulolytic fungus Humicola greatly increased in numbers in the presence of decomposing oat straw whereas Trichoderma was not affected.

¹ Contribution from the Crops Research Division, ARS, USDA, Beltsville, Md. Presented before Div. III, Soil Science Society of America, Dec. 7, 1960, at Chicago, Ill.

² Soil Scientist and Mycologist, respectively.

Received for publication April 16, 1962. Accepted for publication June 4, 1962.