Observations on the epidemiology of <em>Leptosphaeria maculans</em> stem canker in winter oilseed rape.

Gladders, P.; Musa, T.M.

The main source of Leptosphaeria maculans (Desm.) Ces. & de Not. Infection on winter oilseed rape in Cambridgeshire was stubble debris from the previous season. Heavy leaf spot infection of seedlings near unploughed oilseed rape stubble resulted in complete crop loss. The fungus actively colonized stubble debris after harvest and perithecia were formed predominantly on tissues colonized during this period. Ascospores were detected throughout the year, mainly from October to April. The degree of leaf spot infection in the autumn was correlated with stem canker infection at the end of flowering and with severe stem lesions at harvest. The incidence of leaf spot infection was greater in the spring than in the autumn, particularly during the period of extension growth and early flowering. Stem canker infections were first seen in March and continued to develop up to and after harvest.

BRASSICA; LEPTOSPHAERIA; PLANT epidemiology; LEAF spots; PLANT stem diseases & pests; FLOWERS

Plant Pathology, 1980, Vol 29, Issue 1, p28

0032-0862

Academic Journal

10.1111/j.1365-3059.1980.tb01134.x