الفهرس 
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Abstract
SUMMARY
Field experiments were carried out at the Research and Experiment
Station , Faculty of Agriculture at Moshtohor , Zagazig University
in the two successive seasons ( 1981/1982 and 1982/1983) to
investigate the effect of soil application of various nitrogen levels,
and various concentrations of di~ferent foliar micronutrients on the
quantitative and qualitative characters of Egyptian clover and ryegrass
mixture •
Soil analysis of the experimental plots indicated a clay soil
texture with pH value of 7.5
Each experiment included fourty-eight treatments which were the
combination of four soil nitrogen levels, ( i.e. 0.0 , 30 , 60 and 90
kg N/fad) ; four micronutrients ( Zn , Fe , Mn and Cu ) and three concentrations
each of thesemicronutrients ( 0 ,0.1 ,0.2 ; 0 ,0.2 ,0.4 ;
o ; 0.2 , 0.4 and 0, 0.1 , 0.2 % ) respectively.
The design of the experiment was split-split plot , with five
replications • The four nitrogen levels were randomly arranged in the
main plots , the four micronutrients were assigned randomly in the
sub-plots t and their concentrations were devoted to the sub-sub plots.
The area of the experimental unit was 10.5 sq.m.
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Egyptian clover and Italian ryegrass were sown as a mixture
using seed rate of 15 kg and 2.5 kg, respectively for obtaining a
mixture forage stand of 75 % Egyptian clover and 25 % Italian ryegrass •
The main results could be summarized as follows :-
A - Forage yield
(1) In general , applying either 30 or 60 kg N/fad could be enough
to produce high forage yield over the majority of the individual
cuts in the two growing seaSons •
(2) The increase in the total forage yield of the mixture was greater
by applying the first N level ( 30 kg N/fad) compared to the
control • This increase in forage yield started to be slightly
lower at the subsequent higher levels of N application .Applying
60 kg N/fad is the recommended rate for obtaining highly reasonable
forage yield under the circumstances of these experiments •
(3) Foliar application of Mn , Zn , or Cu ; each had a pronounced
effect in increasing the forage yield of the mixture. However,
Mn ranked the first, followed by Zn then Cu for producing the
highest forage yield of the majority of the individual cuts in
the two growing seasons • Meanwhile Fe was the last in this rank.
Either Zn or Cu at 0.1% concentration, and either Hn or Fe at 0.2%
concentration produced the highest forage yield of most of the
individual cuts and the total yield •
(4) No interaction effect of N levels and micronutrient treatments
was found on the forage yield of the individual cuts or~the total
yield •
Combined analysis for the forage yield revealed that :
(5) Applying 60 kg N/fad could be the recommended rate for nitrogen
application as far as the cuts and the total forage yield were
concerned •
(6) Manganese produced the highest total forage yield, followed by
Zn , then Cu followed by Fe with a significant difference between
each of the previously mentioned micronutrients •
(7) Applying 0.2% Mn, 0.1% Zn , 0.1% Cu, and 0.2 %” Fe produced the
highest forage yield of each of the four cuts and the total yield
as well, where the interaction between the applied micronutrients
and their concentrations effects was significant in all cuts except
for the second one •
B - Dry yield:
(8) Applying 60 kg N/fad could be the recommended N level for producing
the highest dry yield of the different cuts and the total yield.
(9) Manganese had the highest effect in producing the top total yield,
then Zn followed by Cu , then Fe , Without significant differences
between the first three micronutrients • Whereas, the difference
in the effect between the first and last one was significant.
(10) Manganese at 0.4% significantly produced the highest dry yield
of all cuts of the two seasons compared with the control • That
concentration produced the highest total dry yield • However ,
the other micronutrlents , Zn , Cu and Fe at the first concentration
level 0.1 , 0.1 and 0.2 % , respectively produ~ed the
highest yield of the cuts and the total yield as well where Zn
followed Mn , then Cu followed by Fe in their effects •
Combined analysis for the dry yield revealed that
(11) Applying 60 kg N/fad is recommended N level for producing the
highest dry yield of the cuts and the total yield of the mixed
stand as well •
(12) Manganese application at 60 kg N/fad could be suggested for
practical and better production , where the interaction effect
was significant • It is also Observed that ”either Cu or Fe
produced the lowest dry yield of most cuts at almost all
nitrogen application levels •
(13) Highest dry yield.was produced by applying Mn , then Zn,followed
by Cu , then Fe.
(14) Applying 0.4% Mn produced the highest dry yield in all cuts , and
the total dry yield as well. However, 0.1% Zn , 0.2% Fe , and 0.1%
eu significantly produced the highest dry yield of the cuts and
the total yield
c - Plant height
(15) Increasing nitrogen application levels caused a continuous significant
increase in the plant height of the two components of the
mixed stand. However, Egyptian clover plants responded to nitrogen
application levels up to 60 kg N/fad, and ryegrass plants up to .
90 kg N/fad.
(16) Manganese was the most important micronutrient in producing the
tallest ryegrass plants in the first three cuts of the two growing
seasons • Whereas, the effect of the applied micronutrients on
the height of Egyptian clover was fluctuating among cuts and growing
seasons having no specific trend •
D - Leaf/stem ratio
(17) Leaf/stem ratio of Egyptian clover was continuously and significantly
increased by applying the subsequent increments of N levels ( 0 to
90 kg/fad) in the first and second cuts • Whereas, the third and
fourth cuts were differently affected • Regarding the two studied
cuts of ryegrass, there was a significant and continuous increase
in leaf/stem ratio as the N application level increased from 0 to
90 kg/fad. This increase was significant in the third cut but not
in the fourth one of the two growing seasons •
(18) Results did not show any’ significant effect for the applied
micTonutrients , concentrations or their interaction on leaf/stem
ratios of either Egyptian clover or ryegrass in the mixture •
E - Leaf area :
(19) Nitrogen levels up to 60 kg/fad is the sufficient dose that is
required for producing high leaf area of Egyptian clover and .
ryegrass in the mixture • These results were reflected on either
forage or dry yield that previously discussed •
(20) Micronutrients did notsignific~nt1y affect leaf area of Egyptian
cloVer in all cuts of the two growing seasons • This was not the
case for ryegrass where leaf area was significantly affected by
the applied micronutrient treatments in the first three cuts of
the two growing seasons. Manganese ranked the first in producing
the highest leaf area of ryegrass with a significant difference
compared with each of the other micronutrients • No significant
effects for the various concentrations of the applied micronutrients
w,ere obtained. .
F - Number of tillers/~egrass plant in t4e mixture
(21) Applying 60 kg N/fad 1s the optimum level for producing the maximum
number of tillers per plant under the circumstances of these
experiments • Th:is N level appeared to be the suggested level for
producing the maximum forage ~nd dry yield of the mixture •
The heighest number of tillers per ryegrass plant was prod~ced
in the middle two cuts
(22) Neither the applied micronutrients , concentrations or the
interaction of both exhibited any significant·effect on the number
... c. j, of tillers/plant . However, Mn at its highest concentration 0.4%
looks to have the highest effect in increasing the number of
ryegrass tillers per plant •
G - Botanical c~osition of the mixed stand :
(23) Ryegrass and weeds fractions of the mixed stand were increased
and Egyptian clover was decreased as the N application level
increased from 0 up to 90 kg/fad.
(24) No specific effect for either micronutrients , concentrations or
their interaction on the botanical composition of the mixed stand
was obtained .,
H - Light intensity:
(25) The highest realistic increase in the amount of light that penetrated
and intercepted by the plant canopies was at 60 kg N/fad
with a continuous significant increase as the N levels increased
from 0 and up to ’this level.
(26) Manganese at the concentration of 0.4% , and Zn at 0.1% sigpificantly
produced less light intensity on the ground surface as
compared to the control. Whereas, no significant interaction·
effect was detected between the different applied micronutrients
and their concentrations •
I - Chlorophyll pigments content :
(27) Nitrogen application level.up to 90 kg/fad significantly increased
chlorophyll a , b and carotenoides in both Egyptian clover and
ryegrass leaves in the mixed stand •
(28). Zinc ,Cu or Fe were the most potent micronutrients that played
a role in promoting the accumulation of chlorophyll pigments and
carotenoides in Egyptian clover or ryegrass in the mixed stand •
(29) The highest accumulation of chlorophyll a ,b and carotenoides
in Egyptian clover were obtained by applying 90 kg N/fad with Zn at
0.2 % for either chlorophyll a or b , and with Fe at 0.4 % for
carotenoides • In ryegrass, 90 kg N/fad with Cu at 0.2% produced
the highest chlorophyll a , band carotenoides •
J - Crude protein content and y~eld :
(30) Applying 60 kg N/fad increased the crude protein content of the
mixture compared with the control by 8.57 , 6.77 , 5.57 and 8.07 %
in the subsequent four cuts , respectively , being 30.0 , 35.8 , .
20.8 and 23.2 % for crude protein yield(31) Manganese 0.4 % produced the highest crude protein content and
yield of the mixture
K - Crude fiber content and yield :
(32) Crude fiber content significantly decreased as N application
level increased from 0 to 90 kg N/fad. Whereas, nitrogen application
increased the crude fiber yield of the mixed forage stand.
(33) No significant effect was detected for the various micronutrient
treatments on crude fiber content • Whereas , the crude fiber
yield was Significantly affected by the applied micronutrients •
the lowest crude fiber yield and Zn or Cu were in between •
Manganese produced the highest crude fiber yield while Fe produced
L - Total carbohYdrates ( CH20 ) content and yield :
(34) The lowest CH20 content was obtained at the highest N application
level and the reverse was true • Whereas , the total CH
2
ti yield
responded differently to the applied N levels compared with the
(35) Manganese significantly produced the highest CH
2
0 yield compared
to Fe which produced the lowest CH
2
0 yield •
M - Fat content :
(36) There wa.s no specific trend for the effect of the applied treatments
on fat content of the forage mixture •
N - Ash content
(37) Ash content increased by the subsequent increase in N application
level up to 90 kg N/fad in the first three cuts and up to
60 kg N/fad in the fourth cut •
(38) Manganese was the most potent element among the other applied
micronutrients in producing the highest ash content • And Zn
ranked the second after Mn with no significant differences between
Mn and Zn in their effect on ash content of the forage mixture.
o - Zinc content :
~ (39) The application of 0.2 % Zn with 90 Kg N/fad accumulated the
highest Zn content •
p - Iron content :
(40) The application of 0.4 % Fe with 90 kg N/fad accumulated the
highest Fe content in the mixture •
Q - Manganese content :
(41) The application of 0,4 % Mn with 90 kg N/fad accumulated the
bj,ghest MIl content in the forage mixture ,
R - Copper content:
(42) The application of 0.2% Cu with 90 kg N/fad accumulated the
highest Cu content
s - Dry matter disappearance :
(43) The highest DMD % was obtained by applying Mh at 90 kg N/fad.