| dc.description.abstract | An experiment was carried out at the Field
Station, University of Nairobi, Kabete Campus to find
out firstly, the effect of nitrogen, (0, 50, 100 and
150 kg N/ha) and phosphorus (0, 17.47, 34i93 and 52.41
kg P/ha) rates, and their interaction on growth, flower
and essential oil yields and quality of chamomile
plants; and secondly whether chamomile plants can grow
under Kenyan conditions and at an altitude above 1800 m
above sea level. The treatments were laid down in a
split-plot design with three replicates. The variety
Max et Oljea was used. The essential oil was extracted
by steam distillation using Clevinger apparatus and its
composition was determined by gas liquid chromatography.
The results showed that vegetative growth and
dry matter production of chamomile plants were significantly
increased by nitrogen application. Nitrogen
at 50 kg Nlha increased significantly both fresh and
dry flower yields of the plants.
Increasing nitrogen application from 0 to 100
kg N/ha, increased essential oil yield per unit dry
flower weight and per plant from 0.627 to 1.036% and
from 5.85 to 16.64 kg/ha., respectively. However,
application of more than 50 kg N/ha did not significantly
increase essential oil yield from the plants.
Essential oil yield per unit dry flower weight increased
with increasing phosphorus application. Increasing
application of phosphorus from 0 to 17.47 kg P/ha. increased
essential oil yield from 0.728 to 0.914%. Applying
more than 17.47 kg P/ha. decreased the essential
oil yield.
Increasing application of nitrogen and phosphorus,
from 0 to 50 kg N/ha, and 0 to 17.47 kg P/ha.
increased chamazulene concentration in the essential
oil from 6.89 to 8.60%, and from 7.07 to 8.25%, respectively.
However, application of more than 50 kg
N/ha and 17.47 kg P/ha. led to a decrease of chamazulene.
Nitrogen fertilization significantly decreased
bisabololoxides "A" and "B" concentration in
the essential oil of chamomile flowers. Increasing
application of nitrogen from 0 to 150 kg N/ha. decreased
bisabololoxides "A" and "B" concentration in
the essential oil from 41.56 to 31.58% and from 21.69
to 13.19%, respectively. Nitrogen fertilization increased
farnesene content in the essential oil of
chamomile flowers. However, applying more than 50
kg N/ha. increased farnesene concentration.
The interactions between nitrogen nad phosphorus,
had no significant influence on chamomile plant
growth, development, yield and quality of the essential
oil.
In general, the results showed that nitrogen
played a vital role in the growth and development of
chamomile plants and in the biosynthesis of the essential
oil and its components from the plants. Phosphorus
fertilization did not significantly influence the
growth and development of the plants. However, it is
recommended that further research should be done in
the areas of plant nutrition, ecological zones, plant
breeding and varietal evaluation, plant biochemistry
and the economic evaluation of chamomile growing in
Kenya. | en |
