POPULATION AND VIABILITY STUDIES OF HELMINTHOSPORIUM SATIVUM IN FIELD SOILS

Publisher Website
Google Scholar
Abstract
The population and viability of spores of Helminthosporium sativum from two locations in each of 100 cultivated fields in Saskatchewan were determined in the spring of 1959. The determinations were made by the flotation–viability count method as described herein. Spore numbers in the different samples ranged from a count of less than 8 to 893 with an average of 118 per gram of soil. A predominant number of the samples contained 200 or less spores per gram. Soils summerfallowed or cropped to cereals in 1958 did not differ significantly in spore populations. The coefficient of correlation between the populations of the paired samples in the fields was 0.83. Viability of spores varied from 11 to 100%; a relatively small number of the samples was in the 11 to 30%, and the others were fairly evenly distributed in the 31 to 100% range. Evidence is presented to support the reliability of the flotation–viability count method. The applicability of the method to studies of various root rot problems and the behavior of certain fungi, other than H. sativum, in soil is discussed.
Keywords

This publication has 2 references indexed in Scilit: