NITROGEN FERTILIZATION OF ZUCCHINI HARVESTED AT DIFFERENT STAGES OF FRUIT DEVELOPMENT

In a field study zucchini cv.
Astra grown from seed drilling was fertilized with nitrogen at the rates of 60-240 kg N ha^-1 applied as a single preplant or split dose with one or two top dressings.
During harvest the fruits of different stages of development according with their length (70-140, 150-210 and 220-300 mm) were picked up from separate treatments.
In the period of maximum fruit setting the samples of fruits were collected for chemical analysis.
Results of the study showed that the maximum yield of small fruits (70-140 mm) was assured by the application of 120 kg N ha^-1, while for more developed ones the most efficient doses appeared to be 180 and 240 kg N ha^-1. Heavy nitrogen fertilization caused the increment of total N and NO₃-N contents, irrespective of the size of fruits.
Harvest conducted in later stages of fruit development increased yield of zucchini fruits, which contained higher amounts of NO₃-N and Ca, while significantly lower level of dry matter, vitamin C total sugars, P, K and Mg.

International Symposium Towards Ecologically Sound Fertilisation Strategies for Field Vegetable Production

E. Kolota, A. Slociak

zucchini (Cucurbita pepo var. giromantina Alef.), N fertilization, fruit length, yield, fruit composition

https://doi.org/10.17660/ActaHortic.2006.700.17