A field trial was conduded during two consecutive seasons (200112002 and
200212003) at the Experimental Farm, Faculty of Agriculture, Ain Shams Univ., Shobra
EI-Kheima, Cairo, Egypt, to investigate the growth, produdivity and quality of Fennel
(Foeniculum vulgare, Mill) as affeded by diversity sources of nitrogen fertilization.
Ammonium nitrate was applied at the rate of 0, 30. 60 and 90 kg Nlfed. as a source of
inorganic nitrogen fertilization. Biogas manure used as organic fertilizer with the levels
0, 40 and 60 kg N/fed., and biofertillzer was applied as inoculation with Bacillus
polymyxa. Irrespective of the concentrations, inorganic fertilizer surpassed all bio-
organic fertilizers. The best records of growth parameters, oit percent, estimated
yields of fruits and oil and nitrogen parameters were obtained by application 90 kg
Nlfed. of mineral nitrogen. Soil inoculation with Bacillus polymyxa significantly
overcame the fruits inoculation with the same inoclum for the aforementioned
paramelers. Biogas manure application at 60 kg Nlfed. produced the highest values of
ali tested parameters in comparison with other bio-organic treatments and control.
The biofertilizers as such or combined with inorganic nitrogen augmented all tested
parameters in comparison with uninoculated plants. Therewithal, soil inoculation with
Bacillus polymyxa and supplemented with inorganic nitrogen 60 kg Nlfed. produced
the highest values of growth parameters, oil content, yields of fruits and oil in
comparison with control, with exception plant fruit yield in the first season wherein 90
kg N/fed. of inorganic N and the same inoculum was the best treatment. On the other
side, application of biogas manure at eo kg Nlfed. + 60 kg inorganic N/fed.
Significantly induced the best records of the most tested parameters. In addition,
biogas manure (8i02) produced the highest values of estimated volatile oil yield,
nitrogen and protein contents and nitrogen uptake, when supplemented with 60kg
N/fed. of inorganic nitrogen.
In concern to essential oil constituents GC analySis of the fruits oil, indicated
that estragole, limonene, fenchone, anethole and v-terpinene are th~ main
compounds of the oil. It was found that the relative percentage of the oil constituents
were fluctuated as a result of interaction among all fertilization sources. In terms of
fenchone compound, which is responsible for fennel bitterness, the interaciion
between aforementioned nitrogen fertilizers reduced its relative percent, trus mean
more favorable taste for the essential oil If used for food dressing.
Counts of total microbia! flora and bacilli influenced by inoculation with
Bacillus po/ymyxa giving an additional increase in the rhizosphere of inoculated
fennel plants. C02 evolution was assayed during the different stages of plant growth, it
was found that using of inoculation, inorganic N-fertilizer and biogas manure gf!\fE-
higher rate of CO2 evoluted from the rhizoephere of inoculated plants than tnose vf
uninoculated one and it was also noticed that soil inoculation treatment surpassed to
fruit inoculation treatment for the previous tested parameter.