Southern blight of sneezeweed and torch lily.

Abstract

Damping off of sneezeweed (Helenium autumnale L.) and torch lily (Kniphofia×hybrida hort.) were found in Mie Prefecture, Japan in 1996. On the soil around the diseased plants, sclerotia of Sclerotium rolfsii Sacardo were formed. The isolated S. rolfsii had pathogenicities to original host plants. Diseases of torch lily and sneezeweed caused by S. rolfsii were first found in Japan. So we proposed to designate the diseases as southern blight of torch lily and sneezeweed. Optimum temperatures for growth of S. rolfsii, which were isolated from torch lily and sneezeweed, were 30°C, and damping off of tomato seedling by each isolate rapidly occurred on 25, 30 and 35°C.