Cultural Growth Patterns and Incompatibility Reactions in Diaporthe and Phomopsis Populations

Comparative studies were carried out with cultures isolated from Phomopsis condiomata and/or Diaporthe ascomata found on naturally-infected living stems or on overwintered stem fragments of Arctium lappa L., Helianthus annuus L., Glycine max (L.) Merr., and Xanihium italicum Moretti, growing in or nearby the same fields in Vojvodina. Results underscored the heterogeneity of the Phomopsis anamorphs in the D. arctii (Lasch) Trav. complex. Intra-specific vegetative incompatibility groups were distinguished among Phomopsis and/or Diaporthe populations from A. lappa. More than one phytopathogenic Phomopsis and/or Diaporthe species were identified on X. italicum. P. longicolla Hobbs was isolated for the first time in Yugoslavia from soybean stem debris. The holomorph Diaporthe {Phomopsis) helianthi Muntanola- Cvetkovic, Mihaljcevic et Petrov showed distinguishing characteristics with respect to other congeneric fungi.