The Development of Diaporthe Phaseolorum Variety Sojae in Culture

ABSTRACT

The development of the Phomopsis state of Diaporthe phaseolorum var. sojae is described briefly. Both α and β conidia are produced from similar phialides. The isolate studied is homothallic but has trichogynes or trichogyne-like hyphae in early developmental stages. Perithecia develop from initials that include an ascogonial coil surrounded by enveloping hyphae. Perithecial initials ultimately differentiate into an outer peridium, a prominent centrum pseudoparenchyma layer, and paraphyses. Peridial and centrum hyphae in the apical region proliferate early in development to produce an elongate, periphysis-lined neck. The ascogenous system develops from the terminal portion of the ascogonial coil by septation of coil cells and subsequent production of short, ascogenous hyphae. The ascogenous hyphae proliferate to form a hemispherical basal hymenium. Asci are produced from croziers. The asci become detached from the hymenium and fill the centrum, compressing paraphyses and pseudoparenchyma. Development of D. phaseolorum var. sojae is believed to be a variation of the basic developmental pattern known in some other Pyrenomycetes.

Key Words:

• Phomopsis
• conidiogenesis
• cytology
• morphology