14
100 200
300 400
500 600
700 800
900
40d
Initial harvest time adding organic
fertilizer
Therefore, we measured the solar intensity intended for determining levels of shade. The data was acquired for 8 hours 9 AM- 4.00 PM by using solar
meter. Figure 5 described clearly the measurement of solar radiation in Field Experiment Research.
Figure 5. The trend of solar irradiance on different of the level of shades. 0 levels of shade, 60 levels of shade, 80
level of shades. It could be seen from figure above that the different on levels of shade
affected the solar radiance acceptation by plant. It indicated that the highest number of solar radiance was 780 wm
2
, 298 wm
2
, 110 wm
2
for each shading level; 0, 60, 80. The lowest number of solar radiance was 443 wm
2
, 108 298 wm
2
and 42 wm
2
with the average was 572.80 wm
2
, 218.9 wm
2
and 57.64 wm
2
for each shading level. Since defoliation management had been influenced forage production, hence it was emphasized on this research. Defoliation
management was implied in this research, including 40, 50, 60 days after plantation Figure 6.
Figure 6. Defoliation management introduced in this research.
40 50
60
First harvest time
Secondary harvest time
Third harvest time
15
10 20
30 40
50
1 5 9 13 17 21 25 29 33 37 41 45 49 53 57 61 R
a in
fa ll
m m
61 Days observation May-June 2012
22 23
24 25
26 27
28
1 5 9 13 17 21 25 29 33 37 41 45 49 53 57 61 T
e m
p e
r a
tu r
e C
61 Days observation May-June 2012
70 75
80 85
90 95
100
1 5 9 13 17 21 25 29 33 37 41 45 49 53 57 61
Hu m
id it
y
61 Days observation May-June 2012
100 200
300 400
1 5 9 13 17 21 25 29 33 37 41 45 49 53 57 61 S
o la
r R
a d
ia n
c e
c a
l m
2
61 Days observation May-June 2012
An experimental field treatment showed three different levels of irradiance shading for forage crop. At the beginning information several data was obtained
related to microclimate condition among the research field. 61 days data observation was gained. The data showed the highest temperature was 27.1
o
C, and the lowest was 23.4
o
C, with the average was 26.18
o
C. The highest humidity was 95 and the lowest was 73 with the average of humidity was 83.06. The
measurement of rainfall showed, the highest rainfall was 44.1 mm and the lowest was 0.5 mm with the average was 11.89 mm. The solar irradiance measurement
showed the highest number was 378 calm
2
and the lowest number was 296.68 calm
2
. Figure 7 described clearly the information of microclimate condition, data source from Indonesia Meteorology and Geophysics Agency.
Figure 7. Showed the microclimate condition among the research field at Field
Work Center, Faculty of Animal Science, Bogor Agriculture University, a Temperature, b humidity, c rainfall, d solar
irradiance.
3.3. Soil and Fertilizer Analysis Measurement
Soil and fertilizer analysis was measured in BALITRO, Bogor. The following method of measurement could be seen on Table 4.
16
Table 4. The analyses of Fertilizer and Soil Sample No
Parameter Method
Fertilizer 1
pH pH meter
2 N
Kjeldahl 3
P Spectrophotometer
4 K
AAS 5
C-Organic Spectrophotometer
Soil 1
pH pH-metri
2 C-Organic
Walkey Black 3
N-Total Kjeldahl
4 P ppm
Bray l 5
K Percolation with NH
4
C
2
H
3
O
2
1M In this research the utilization of organic fertilizer manure from cattle
was used. The information regarding component of organic fertilizer used soil quality analysis provided in Table 5 and 6.
Table 5. The Information of Component of Organic Fertilizer Analysis measured in Field Center Experimental Research Faculty of Animal Science,
Bogor Agriculture University. Compound
Amount N
2.17 P
0.36 K
0.28 Organic Carbon
31.88 pH
6.5 Table 6. The Information of Soil Quality measured in Field Center Experimental
Research Faculty of Animal Science, Bogor Agriculture University Levels of
shades pH
Organic carbon
N-Total CN Ratio
P K
60 5.14
2.06 0.22
9.36 6.88
0.11 80
4.74 2.5
0.28 8.93
8.28 0.15
3.4 Sampling Procedure and Data Collection 3.4.1 Plant Production
On the day after plantation determined, the plant harvested and weight by using electrical balance. P. purpureum was chopped and reminded 10 cm from
17 ground whereas S. Splendida was cutting and reminding 5 cm from ground.
Remove sample from any roots from plants and brush off dirt particles. Fresh weight was measured and dried in 65
O
C for 48 hours and weighted again. Plant biomass was converted into Mgha in dry weight basis. Leaves were grinded
partially dried sample into fitness desired for analyses.
3.4.2 Forage layer height and leaf area
The measurement of forage layer height cm was done by measuring from the soil surface to the highest point of the arch of the uppermost leaf. We were
using stick ruler with the maximum length was 3m. We also focused on measurement on leaf area mm
2
. It measured by using leaf area meter. Both forage layer height and leaf area were completed in 60 days after plantation.
3.4.3 The measurement of Chlorophylls Content.
The following analysis was performed on chlorophylls content, including chlorophyll a and chlorophyll b. Small sward was cut and used as a sample; the
third and forth leaves from the bottom of the ground. Fresh leaf was breaking into simpler form and measured for 1 gram. It was destructed and dissolved by using
80 acetone for 2 ml. Sample was centrifuged and diluted for 5 ml. Sample of chlorophyll were observed by using spectrophotometer UV-Vis on the wave
length 663 and 645 nm. The calculation of total chlorophyll the a and b chlorophyll was counted by using equation Yoshida 1981:
a chlorophyll = 0,0127 x D
663
–0,00269 x D
645
fp b chlorophyll = 20,2 x D
645
+ 8,02 x D
663
fp fp = dilatation factor = de x bc x 1a x 1.000
Information A = weight of sample
B = initial extract volume C = the extract volume obtained from the initial extraction
D = extract volume after destructed E = conversion from litter to millimeter
1.000 = conversion from gram to milligram
18
D663 = spectrophotometer on 633 nm wave length D645 = spectrophotometer on 645 nm wave length
3.4.4 The analyses of forage quality
Since the feed was not only focused on the quantities rather its quality. Moreover the main process of growth from forage was obtained form
photosynthesis process. However, the product of photosynthesis would be transferred into the organ for the growth and maintenance. The product of
photosynthesis was the dry matter production and others nutrients compound. Hence, the nutrients content analyses were measured on moisture analysis, dry
matter production, ash analysis, fat content fiber content and protein content respectively.
3.4.4.1 Dry Matter Analysis
Dry matter analysis was measured based on AOAC method Association of Official Analytic Chemist. The Total Dry Matter by Oven Drying at 105
o
C for 16 hr. The principle mechanism was emphasized on the heat treatment 105
C. Water would evaporated by heat treatment, remaining the rest material dry
matter that would be weighted formerly. Total dry matter is determined gravimetrically as residue remaining after drying. Weighing made on hot sample
or after cooling in desiccator. The calculation of moisture content could be seen on equation:
Where W
1
= dry weight of sample and container with cover in grams W
2
= tare weight of container with cover in grams W
3
= dry weight of sample in grams Percent Total Moisture was calculated as:
Total Moisture = 100 - Total DM
