Js. Johnk et Rk. Jones, COMPARISON OF WHOLE-CELL FATTY-ACID COMPOSITIONS IN INTRASPECIFIC GROUPS OF RHIZOCTONIA-SOLANI AG-1, Phytopathology, 84(3), 1994, pp. 271-275
Gas chromatography and integrated computer software (Microbial Identif
ication System, Microbial ID, Inc., Newark, DE) were used to identify
and compare fatty acid compositions among isolates representing three
intraspecific groups of Rhizoctonia solani anastomosis group 1 (AG-1).
The major fatty acids found, constituting 94-96% of the C9-C20 fatty
acids present, were linoleic (18:2 cis 9, 12), oleic (18:1 cis 9), and
palmitic (16:0). Smaller amounts of nine other fatty acids were consi
stently identified in preparations from 2- and 4-day-old cultures. Lib
rary entries were generated for the intraspecific groups AG-1 IA, AG-1
IB, and AG-1 IC. A dendrogram of these library entries showed that AG
-1 IA and AG-1 IB are very closely related in fatty acid composition,
whereas AG-1 IC is different. Intraspecific group libraries challenged
with independent isolates could be used to identify most isolates of
AG-1 IB and AG-1 IC but not AG-1 IA. Most of the isolates of AG-1 IA w
ere identified as AG-1 IB.