INCREASING THE DRY MATTER PRODUCTION IN BULB ONIONS (Allium cepa L.)

Investigations have been carried out at the Research Centre Aarslev with the aim of increasing the dry matter content and production in spring sown bulb onions (Allium. cepa L.). New and old long day cultivars have been tested for total dry matter production, dry matter content, and quality characteristics.
On average a dry matter content of 13 per cent has been found with a variation from 11 to 14 per cent.
Higher contents are seen in old cultivars of Stuttgarter or new breedings of shallot cultivars (Allium. cepa var. ascalonicum). Dry matter content increases during the period of bulb development.
Harvesting later than 80-90 per cent top fall over reduces dry matter content and storage ability.
Cutting off the onion leaves before harvest and lifting the crop for artificial drying instead of wind-rowing decreases dry matter content and total dry matter production.
Increasing the nitrogen supply above 200 kg N per ha decreases dry matter content in mature bulbs.
During the storage period from November to July the dry matter content decreases slowly as a result of respiration loss.

II International Symposium on Edible Alliaceae

K. Hendriksen, S.L. Hansen

composition, carbohydrates, storage, harvest time, fertilization, cultivars

https://doi.org/10.17660/ActaHortic.2001.555.20