الفهرس 
Material and methodsOnly 14 pages are availabe for public view
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Abstract
Two field experiments were carried out at the Experimental
Farm of the Fac. Agric. Moshtohor, Zagazig University (Benha
Branch) during the winter seasons of 1995/96 and 1996/97.
The aim of this study is to elucidate the combined effect of
organic and mineral N-fertilization on growth, chemical
composition of plant foliage, yield and quality of cabbage. The
biological activity, organic carbon, total nitrogen, ammonical-N and
nitrate-N in the soil in different periods were also determined. The
experiment was carried out to investigate the response of cabbage
plants (Brassica oleraceae vaT.capitata cv. Improved Baladi) to the
effect of two organic manures i.e., biogas and farmyard manures
(FYM) as organic nitrogenous sources combined with ammonium
nitrate as a mineral fertilizer. This experiment included ten
treatments. Eight of them were the combinations of the used two
;Organic manures and four levels of mineral nitrogen i.e., 20,40,60
and 80 kg N/fed. and then it was completed by using 60, 40, 20 and
o N kg/fed organic manure source to reach the standard level of
cabbage Nsfertilization i.e., 80 kg N/fed. In addition to the
previously mentioned eight treatments, the treatment of 80 kg N as
ammonium nitrate only beside the control one (without any /
application of fertilizers) were used to form ten treatments.
A completely randomized plots design with four replicates
was adopted. Agncultural practices were done as commonly
followed in the district.
The obtained results could be summarized as follows:
1. Vegetative groW1th characteristics (at 75 days after
transplanting):
1-1. Fertilization of cabbage plants with 20 kg N as anUnonium nitrate
+ 60 kg N as biogas manure (BM) led to a significant increment
in the vegetative growth characteristics expressed as plant
height, stem length, number of leaves per plant and fresh weight
per plant: Meanwhile, fertilizing plants with 80 kg N/fed. of the
biogas manure gave a significant increment in stem weight and
the percentage of dry matter in leaves and stem.
1-2. Using 20 kg N ammonium nitrate + 60 kg N as organic
fertilizer ”biogas manure” gave the highest significant values
of the photosynthetic pigments expressed as chlorophyll a, b,
a + b and total carotenoids. This was true during both seasons
” of growth.
1-3. Cabbage plants that fertilized with 20 kg mineral-N + 60 kg
organic-N (biogas manure) showed a significant increment in
the plant.leaves content of the chemical constituents i.e., total
N, N03-N, P and K. Meanwhile, it is worthy to mention that
treatment of 60 kg N as ammonium nitrate + 20 kg N as FYM
showed the highest values in N and K content especially in
the first season, but such values didn’t reach the level of
significancy at 0.05 as compared with the distinguished
treatment i.e., 20 kg N of ammonium nitrate + 60 kg N of the
biogas manure.
2- Vegetative growth characteristics (at 115 days after
transplanting):
2-2. Fertilizing cabbage plants with 20 kg N as mineral nitrogen +
60 kg N as biogas manure led to a significant increment in all
the vegetative growth characteristics expressed as plant
height, stem height, fresh weight per plant, stem weight, head
weight and thl~ dry matter (%) of leaves and stem. However,
the dry matter (%) increments of stem didn’t reach the level of
significancy in the first season.
3- Head physical characteristics and total yield:
3-1. Using 60 kg N (mineral-N) + 20 kg N (FYM) showed the highest
values with respect to the number of leaves (outer, inner and
total) and head diameter especially in first season. Moreover, the
same treatment resulted in the highest values with respect to the
number of inner leaves and head length especially in the second
season. However, no significant differences were detected
between such treatment and that where 20 kg mineral N + 60 kg
N of the biogas manure was used.
3-2. Concerning the effect on total head yield and quality, the
treatment at which 20 kg mineral Nin the form of ammonium
nitrate + 60 kg organic nitrogen/fed. as a biogas manure
proved to be the most effective treatment in improving the
physical characteristics and total yield of the cabbage head.
4- Head leaves cnemtcal composition:
4-1. The significantly highest values of the chemical constituents of
cabbage head leaves i.e., total N, N03-N, Pand K contents
were obtained by using 20 kg N as mineral source + 60 kg
N/fed., applied as biogas manure. Meanwhile” the differences
between the above mentioned treatment and those of 60 kg
mineral N + 20 kg N of Fr’Mssource, 40 kg mineral N + 40 kg
N fed added as biogas and 0 kg mineral N + 80 kg N/fed. of
biogas manure source didn’t reach the level of significancy at
0.05.
4-2. Fertilizing cabbage plants with 20 kg mineral N + 60 kg N/fed.
of the biogas manure led to a significant increment in
reducing, non-reducing and total sugars as well as vitamin C
leaves content.
5- Biological activity, organic carbon, tetal nitrogen,
ammonical-Nand nitrate-N in the experimental soil:
5-1. The biological activity (C02 evolution):
It was recorded that the N-supplements either in the form of
chemical fertilizer or organic manuring (FYM or BM)
increased the microbial respiration and CO2 output in the soil.
The combination between the nitrogen fertilizer as an organic
supplements and that of the mineral Nsfertilizer clearly
increased the biological activity. It is also” evident that the
biogas manure addition clearly pronounced higher biological
activity in the soil than that of the farmyard manure.
5-2. The combination between organic manures (B~1or FYM) with
mineral N-fertilizer led to an increment in the carbon
mineralization in the soil. Comparing the obtained results
from the two sources of manure it could be noticed that biogas
manure was Inore effective than farmyard one in microbial
activity and organic carbon mineralization in the experimental
soil.
5-3. Comparing the effect of mineral N-fertilizer with that of the
two sources of the organic manures (BM & FYM) on the total
nitrogen concentration in soil, the results revealed that biogas