THE EFFECTS OF PLANTING DENSITY AND NITROGEN NUTRITION IN EARLY PRODUCTION OF LEEKS

In field study conducted in 1991–1992 leeks cv.
Kilima was grown from seedlings raised in the greenhouse in pressed soil blocks and planted in the middle of April at the density of 40, 54 or 80 plants/m². Nitrogen was supplied as a preplant fertilization at the rates of 100 and 150 kg N/ha or in split doses: 100 + 50 kg N/ha or 100 + 100 kg N/ha.
During the harvest done in the third decade of July the marketable yield of leeks including plants of 10–15, 15–20 and >20 mm in stem diameter was determined.
Index parts collected twice during the growing period as well as edible parts taken at harvest were analysed for macronutrients content.

The results of the study proved that marketable yield of leeks increased from 39.87 t/ha to 43.60 t/ha and 48.08 t/ha if the plant population was enhanced from 40 to 54 and 80 per lm². The adverse effect was observed concerning the mean weight of plant which declined from 117 to 104 and 84 g respectively.
Irrespective of plant population, the most efficient method of leeks fertilization appeared to be the application of 100 kg N/ha before planting and 50 kg N/ha as a top dressing.
No significant differences in yield and its quality was found if the preplant dose was enhanced from 100 to 150 kg N/ha.
The macronutrients content in leeks was not dependent on plant spacing, while split application of nitrogen, especially at the rate of 200 kg/ha considerably increased the amount of total N and NO₃-N in the crop.

VII International Symposium on Timing Field Production of Vegetables

E. Kolota, K. Adamczewska-Sowinska

leeks, plant population, nitrogen nutrition, yield, mineral contents

https://doi.org/10.17660/ActaHortic.1994.371.53