Fusarium Wilt and Corm Rot of Freesias

Abstract

1. Fusarium wilt and corm rot of freesias is prevalent in California, Florida, and Indiana, and has become destructive in Texas with the introduction of extensive freesia growing. Four species of Fusarium, F. bulbigenum, F. martii-minus, F. moniliforme, and F. solani, were isolated from infected freesia corms, and reproduced the disease in inoculation experiments. F. conglutinans from cabbage plants and F. lycopersici from tomato plants also induced typical symptoms on inoculated freesias; and five other Fusarium species were found able to cause somewhat less severe injury. It is probable that other species of Fusarium may at times cause wilt and corm rot of freesias. The disease is carried by infected corms, by old remnants of infected plants, and by the soil. 2. Fusarium solani and F. martii-minus caused decay of inoculated onion bulbs, but the other two Fusarium spp. isolated from freesia corms did not attack onions. Normal gladiolus corms planted in soil inoculated with the four species of Fusarium from freesias were attacked by a decay of the plates, which also prevented development of new roots.