PHYTOPHTHORA TROPICALIS, A NEW PATHOGEN OF ORNAMENTAL PLANTS IN POLAND

Abstract

From Hedera helix and Epipremnum aureum showing necrosis of shoot base spread upwards and on leaves Phytophthora tropicalis was isolated. The species was obtained from ⅞ of Hedera and ¾ of Epipremnum diseased shoot and root parts. Additionally, Botrytis cinerea, Fusarium avenaceum and Rhizoctonia solani was recovered from some of affected plants. The chosen 2 isolates colonised petioles and leaf blades of both host plants. P. tropicalis caused necrosis of leaves of 11 tested cultivars of H. helix and 13 other pot plant species and seedlings of tomato. The fastest spread of necrosis was observed on leaves of Peperomia magnoli- aefolia, Pelargonium zonale and Phalaenopsis x hybridum. The development of disease was observed at temperatures ranged from 10 to 32.5°C with optimum 30°C.