Abstract:
Two field experiments were
carried out to investigate the optimum
nitrogen rate (80, 100 and 120 kg N fed.-1;
Fed = 0.38 ha) and stimulative compounds,
i.e. foliar spraying with water, as control,
Azotobacter spp. and Azospirillum spp.,
yeast, compost tea and humic acid on
vegetative growth, yield, quality, as well as
storability of bulb yield of onion (Allium
cepa L.) under North Delta conditions. The
results showed that the vegetative growth
was positive influenced, also yield its
components, quality and storability of onion
were related to the medium rate of nitrogen
(100 kg N fed.-1). Furthermore, foliar
spraying with humic acid at the rate of
1 kg fed.-1 led to a significant increment in
the most of vegetative growth
characteristics, as well as total bulb yield
and its components, bulb quality and
storability of onion. Both of 100 kg N fed.-1
and spraying humic acid at the rate of 1 kg
fed.-1 significantly increased most vegetative
growth characteristics, total and marketable
bulbs yield fed.-1, bulb quality and
storability of onion. So, this study
concluded that onion farmers at North Delta
of Egypt should fertilize onions with
nitrogen at the rate of 100 kg N fed.-1 with
spraying humic acid at the rate of 1 kg fed.-1
to achieve the highest economic yield.