Fusarium diseases of cereals : IV. Observations on Fusarium nivale on wheat

Abstract

Isolates of Fusarium nivale (Fr.) Ces., (Calonectria nivalis Schaffn.) from barley, oats and wheat, differed in their growth and sporulation on potato sucrose agar and in their pathogenicity to wheat. F. nivale caused pre-emergence death when infected wheat seed was sown in the field. Diseased seedlings had brown lesions on roots, coleoptiles and leaves and produced few tillers initially. Mature infected plants showed browning of the leaf sheaths on which perithecia were usually produced. Infection spread through a crop in three phases, initially by means of mycelia and conidia, later by ascospores and at flowering by both ascospores and conidia produced on the upper parts of the mature plants. Infected grain was shrivelled but germinated well under laboratory conditions.