Cause This physiological condition is caused by high temperatures and/or moisture stress during tuber development. Also known as sugar end or jelly end.
Symptoms Affected tubers usually are pointed on the stem end, although bud ends also have been observed with translucent end. Tuber flesh from the affected area is translucent or glassy, devoid of starch, and usually high in reducing sugars. Tubers usually break down in storage or, if processed, produce dark fry products due to elevated sugar levels.
Cultural control
- It is very important to manage soil moisture to minimize water stress during development. Using sprinklers and soil water monitoring equipment facilitates irrigation management.
- Some varieties (Lemhi, Nooksack) are less susceptible.
- Plant in moderate soil types; avoid planting in heavier clay soils.