Botrytis cinerea and Colletotrichum acutatum are important strawberry pathogens Nitrogen (N) application can increase yield but also susceptibility to pathogens Strawberry plants (Camarosa and Ventana) were grown in sand fertilised with base nutrients plus ammonium nitrate ammonium sulphate or calcium nitrate at low (40 ppm N) and high (140 ppm N) concentration Controls consisted of base nutrients only and water only Flower production fruit yield and berry size all increased with increasing Nconcentration but Nsource itself was not important Disease susceptibility was affected by both Nconcentration and Nsource At high Nconcentration C acutatum fruit lesions were largest in ammonium sulphate treatments > ammonium nitrate > calcium nitrate; Botryits cinerea lesions were largest in ammonium nitrate > ammonium sulphate > calcium nitrate Similar trends were observed for leaf susceptibility to the two pathogens These data suggest that calcium nitrate may be a suitable source of nitrogen helping growers to reduce disease risk

New Zealand produces approximately 5,500 tonnes of brassica seed per year, two thirds of which, valued at $13M, is exported. Black rot caused by Xanthomonas campestris pv. campestris is a common disease of brassicas, and while crop losses are not extensive in New Zealand, internationally total crop losses have been reported. Seeds are the primary source of inoculum and the ease with which this inoculum spreads means that even small traces can cause severe epidemics. Genetic resistance to black rot is a complex trait which makes breeding for resistance in brassicas challenging. The effectiveness of chemical and cultural practices is variable. Biological control with natural antagonistic microbes may provide a more effective means of controlling black rot and other pests and diseases, and create opportunities for increasing the export value of brassica seed. Current cultural practices and the potential for biological control for the management of black rot are reviewed. Keywords: biocontrol, Brassicaceae, crucifer