Viability of sporangia of Phytophthora infestans in relation to drying

• Published in: Transactions of the British Mycological Society Vol. 64; no. 1; pp. 73,IN5 - 78,IN5
• Main Authors: Warren, R.C., Colhoun, J.
• Format: Journal Article
• Language: English
• Published: 01.01.1975
• ISSN: 0007-1536
• DOI: 10.1016/S0007-1536(75)80077-5

The effect of drying on the viability of detached sporangia of Phytophthora infestons was studied at 95 % r.h., 90 % r.h. and in a saturated atmosphere. Sporangia produced on potato plugs bore a water film which influenced the rate at which sporangial germination was eliminated. In the presence of a water film no germination occurred after drying at 95 % r.h. for 20 min whereas in the absence of this film sporangia failed to germinate after drying at g5 % r.h. for 5 min or at 90% r.h. for 2·5 min. Slow rewetting of dried sporangia which failed to germinate, or exposure to chemicals, media or host tissue failed to induce germination. Dried sporangia which failed to germinate were found to be vacuolated and the cell membranes were damaged.