The evaluation of keeping quality in the variety testing system is conducted on a five-point scale, where high keeping quality corresponds to a marketable yield of more than 90%, and low — less than 75%. The genetic potential of a variety determines the limits of suitability: southern cultivar types usually have a shorter dormancy period compared to varieties specialized for winter storage.
The most important agrotechnical condition for ensuring keeping quality is balanced mineral nutrition. Excess nitrogen in the second half of the growing season prevents the full maturation of the bulb neck, promoting the development of rots, while potassium fertilizers contribute to the formation of dry outer scales.
Technological maturity, necessary for successful storage, occurs at mass lodging of the tops (about 70%). Subsequent high-quality drying of the bulbs is a mandatory step that minimizes the risk of infection with neck and bacterial rots and ensures the preservation of marketable qualities until spring.
General information about the subject — on the page
Keeping quality.