The aim of this trial was to assess if potatoes grown under mesh crop cover protected the plants from late-blight – see blog of Dec 10th, 2017.
This summer the Sarvari Research Trust took part in this project to find out if crop covers (mesh) could control late-blight disease on potatoes. Ali Bates of Pandy Farm, Tregarth, hosted the trial on his potato field planted with several varieties. Mesh was supply by Organic Research Centre and was placed in position in July.
Well, we would have to choose to do a blight trial in the first summer for ages to have no blight. Plants struggled to stay alive and were frequently wilting and stopped growing in the worst drought we have had since 1976. The field was monitored for blight. Even at the end of the season in September when tops were cut prior to harvest, no foliage blight was observed. The yield of marketable tubers from covered plots was compared with adjacent control plots. Unfortunately the covered plots did not yield more than the control plots. A similar trial was conducted on several other farms. I wonder if they had more exciting results.
Conclusion: It has not been possible to assess if crop covers can control blight. Similar experiments in New Zealand claimed to have excellent inhibition of foliage blight under mesh covers. However, the leaf disease was not diagnosed and could have been caused by a pathogen other than P. infestans. It is possible that the project might run again next year. We will get plenty of late blight, I feel sure!
You will find more information about the project here. LWA/OGA Potato Blight group