Journal article

Publication year: 1994

Pages: 31-38

Journal: Phytopathology

Volume number: 84

Issue number: 1

ISSN: 0031-949X

eISSN: 1943-7684

DOI Link: https://doi.org/10.1094/Phyto-84-31

Publisher: American Phytopathological Society

Abstract: 
We used starch gel electrophoresis to investigate isozyme variation among 194 isolates of races 0, 2, and 3 of Cochliobolus carbonum collected in 1987 in two corn fields in North Carolina as well as six isolates of race 1 from previous collections in different states of the United States. Of eight enzyme systems studied in detail, only one, phosphogluconate dehydrogenase, was monomorphic. Diaphorase, malate dehydrogenase, glutamate oxaloacetate transaminase, and esterase were highly polymorphic in race 0, whereas isozyme variation in races 2 and 3 was very limited. Race 0 accordingly had a significantly higher average gene diversity than did race 2 or race 3. Genetic similarity between races 2 and 3 was very high. Their allele frequencies differed clearly at only two putative esterase loci. Races 2 and 3 were only distantly related to race 0, as demonstrated by cluster analysis and principal coordinates analysis. There was no apparent genetic variation among five race 1 isolates from North Carolina and South Carolina. Their common electrophoretic type occurred also in race 2 but not in race 0 or race 3, suggesting a common ancestry with race 2. Only a small proportion of race 2 and race 3 isolates or race 2 and race 0 isolates shared common electrophoretic types, which suggests that there is little, if any, genetic exchange between these races.

Harvard Citation style: WELZ, H., KOHLER, W. and LEONARD, K. (1994) ISOZYME VARIATION WITHIN AND AMONG PATHOGENIC RACES OF COCHLIOBOLUS-CARBONUM ON CORN IN NORTH-CAROLINA, Phytopathology, 84(1), pp. 31-38. https://doi.org/10.1094/Phyto-84-31

APA Citation style: WELZ, H., KOHLER, W., & LEONARD, K. (1994). ISOZYME VARIATION WITHIN AND AMONG PATHOGENIC RACES OF COCHLIOBOLUS-CARBONUM ON CORN IN NORTH-CAROLINA. Phytopathology. 84(1), 31-38. https://doi.org/10.1094/Phyto-84-31