VIEW ARTICLE

Relationship of Age of Soybean Seedlings and Inoculum to Infection by Pythium ultimum. F. A. Laviolette, Assistant Professor, Department of Botany and Plant Pathology, Purdue University, Lafayette, Indiana 47907; K. L. Athow, Professor, Department of Botany and Plant Pathology, Purdue University, Lafayette, Indiana 47907. Phytopathology 61:439-440. DOI: 10.1094/Phyto-61-439.

The relationship of age of plant and inoculum to infection by Pythium ultimum was studied by inserting 4- to 20-day-old mycelium into the hypocotyl of soybean seedlings 8-14 days of age. Nearly 100%, 8-10 days of age, were killed with 4- to 8-day-old mycelium. The percentage killed progressively decreased with increased age of mycelium and/or increased age of plant.