Key Points:A replicated trial was set up in a commercial crop at Levels, South Canterbury with potato cultivar Innovator, planted on 12 October 2015. The trial site was four years out of potatoes.A number of diseases were found in the sampled plants and tubers including Spongospora root galling and tuber powdery scab; Rhizoctonia stem canker and tuber black scurf; Sclerotinia white mould on stems, black leg on stems, and common scab on tubers.Rhizoctonia stem canker and Spongospora diseases predominated, while the other diseases were at very low incidence levels.Nebijin® reduced the severity of powdery scab on tubers at both assessment timings and this reduction was statistically significant when compared to the nil treatment. None of the other treatments affected any of the diseases observed in the trial.There were no statistically significant differences between the treatments for unmarketable or marketable yields. Overall mean yield of marketable tubers was equivalent to 82.8 t/ha.
No. 8 Seed tuber and in-furrow fungicides on soil-borne diseases
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