By Vikram Bisht and Xiaowei Guo MAFRD
Aug. 19, 2014, Manitoba – Continuously hot and humid weather could have impacts on potato tuber production in different degrees, reports Vikram Bisht and Xiaowei Guo with the potato and horticultural crops department at Manitoba Agriculture, Foods and Rural Development, in the latest potato disease report.
Most potato fields have been or are being irrigated to avoid plant water deficits, however, excessive moisture in the soil or high relative humidity under the plant canopy could result in nitrate leaching and disease developing. P-Days ranged from 604 to 626.
The muggy weather favoured disease development recently. There was no late blight disease reported or found. The seven-day DSV's ranged from 2-5, 3-7 and 4-7 in the southern, central and western areas, respectively. Therefore, the seven-day schedules of fungicide application and field scouting are still recommended at the current stage.
Early blight jumped to the top of the diseases occurring on potato plants so far. In some fields, two to three fungicide applications have been done for this disease. Application of systemic fungicides for early blight disease is recommended. Blackleg, verticillium wilt and white mould were not significant yet.