MARDI Res.Bull., (1985)13,3: (225-217)
SHADE TOLERANCE POTENTIAL OF SOME TROPICAL FORAGESFOR
INTEGRATION WITH PLANTATIONS
1. GRASSES
C.C. WONG*, H. RAHIM* and M.A. MOHD. SHARUDIN.
Keywords: Shade, Nitrogen, Dry matter productivity, Tillering, Grasses,Tropical forages.
RINGKASAN
.12
jenis rumput tropika telah dinilaikan dengan menggunakan
Ketahanan terhadap naungan bagi
naungan buatan di dalam rumahkaca pada kadar 64Vo, 30%, 78Vo dan 97c cahaya yang sesuai untuk
fotosintisis (photosynthetic quantum flux - PHAR) berbanding dengan cahaya matahari sepenuhnya.
I n i d i i k u t i d e n g a n p e r c u b a a nd i l a d a n g u n t u k m e n i l a i k e u p a y a a ne n a m j e n i s r u m p u t t e r p i l i h p a d a k a d a r
cahaya l00To (kawalan), 60Vo. 34Vo dan 18Vc PHAR daripada cahaya matahari sepenuhnya dan
dipotong setiap enam minggu dan sepuluh minggu.
D a l a m k a j i a n d i r u m a h k a c a , n a u n g a n m e n g u r a n g k a n p e n g e l u a r a na n a k r u m p u t ( t i l l e r ) , h a s i l
bahan kering bagi pucuk, daun. batang, tunggul dan akar dengan berkesan (P<0.01), tetapi
menambahkan keluasan permukaan daun. Dalam keadaan naungan, pembahagian bahan kering
kepada komponen daun yang melebihi akar memberikan peningkatan nisbah pucuk/akar dan daun/
batang. Purata pengurangan hasil bahan kering di antara rumput-rumput ialah 28.7%,63.3Vo dan
82.4Vo betbanding dengan kawalan bagi pengurangan cahaya sebanyak 44Va,66Va dan 827o daripada
cahaya PHAR di dalam rumahkaca. Rumput-rumput yang terbaik dan sesuai di bawah naungan ialah
Panicum maximum, P. maximum cv. Tanganyika, Digitaria setivalva dan Brachiaria decumbens'
Spesies-spesiesSetaria sphacelald cv. Kazungula, Digitaria decumbens cv. Transvala dan B. ruziziensis
sangat kurang ketahanannya terhadap naungan. Pada naungan yang banyak (97o PHAR), rumputrumput tempat an iaitu Paspalum conjugatum dan Axonopus compressusdisenaraikan di tempat ketujuh
dan keempat selepas rumput spesies-spesiesPanicum.
Bagi percubaan di ladang pula, P. maximum dan B. decumbens memberikan hasil yang tertinggi
pada semua paras naungan. Pengurangan hasil purata bahan kering terhadap enam jenis rumput ialah
23.1% dan 37.67c t:erbanding dengan kawalan bagi cahaya 667o dan 82% PHAR daripada cahaya
matahari sepenuhnya. Axonopus compressus dan P. maximum var. trichoglunre menghasilkan bahan
kering yang tertinggi pada paras naungan sederhana dan dipotong setiap enam minggu atau sepuluh
minggu. Rumput-rumput tegak di bawah naungan yang dipotong setiap sepuluh minggu memberikan
pengeluaran anak rumput dan hasil bahan kering yang tinggi. Sementara itu potongan setiap enam
minggu memberikan hasil yang tinggi bagi rumput-rumput yang bukan berjenis tegak seperti ,4.
compressus dan P. conjugatum.
Bagi rumput-rumput di bawah naungan yang banyak adalah dicadangkan supaya jangka masa
potongan dipanjangkan untuk meninggikan lagi kandungan botani dan kadar penghidupannya. Pada
amnya, kandungan nitrogen bertambah mengikut kadar naungan dan jangka masa potongan yang lebih
pendek. Rumput-rumput yang kurang penghasilannya, seperti S. sphacelata cv. Kazungula dan ,4.
compressus, mempunyai kandungan nitrogen yang tinggi. Panicum maximum var. trichoglume
mengandungi paras nitrogen yang terendah.
Keputusan-keputusan lain dibandingkan dalam hubungan terhadap pengurusan pastura di dalam
tanaman perladangan.
production potential of tropical forage and
pasture grassesunder a wide range of light
regimes as encountered at different stagesof
plantation crop development in the humid
tropics. The problems of integrating pastures,
livestock and tree crops have been high-
INTRODUCTION
With the current increasinginterestin
multiple land use incorporatingcrops such
as pastures with plantation agriculture,
there is a void of information on the relative
*Livestock Research Division, MARDI,
Serdang, Selangor, Malaysia.
225
lighted by THot'lns (1978). Shading experiments had been attempted to identify shadetolerant species (WHIreltnN, BosonQusz
1,978; ERtxsEN and
and Raxecou,
WHrrNp,v, 1981). Results from a grazing
trial on some improved tropical forages in
5-year-old oil palm at Serdang indicated few
improved species of legumes which were
tolerant to very low light regimes (CHeN,
CHING, A:m and HASSTN, 1978). As the
grasses were planted under an already
closed canopy, the light limitation and root
competition from the existing oil palms
could have posed constraints to effective
establishment.
design was a Randomized Complete Block
in a split-plot arrangement with three
replications.
Soil belonging to Tropeptic Haplorthox
series was collected from 0-40 cm depth
and mixed with one third by volume of fine
sand. The mixture was then sieved through
a 0.5 x 0.5 cm screenand air-dried. To each
cubic metre of the mixture, 2 kg NPK
compound fertilizer (I4:1.4:I4) were added
and mixed thoroughly before potting. Plastic
pots, measuring 16.5 cm in diameter, were
each filled with 2.5 kg of the air-dried soil
mixture and planted with two or three tillers
of the grassesunder study.
In newly established plantations, the
interrows are generally wide and receive
almost complete or full solar radiation. It is
at this early stage of plantation development
that the potential for forage integration with
plantation crops could be exploited for
subsequent utilization in the later years
when light gradually becomes limiting.
Dead tillers were replaced until
completed establishmentwas obtained. The
established grasses were then allowed to
grow for four weeks before a uniform
cutting at 5-cm stubble height was undertaken to promote tillering. A second
uniform cutting was imposed four weeks
later just prior to the introduction of shade
levels obtained by varying the density of
shadescreens.The photosyntheticquantum
flux (PHAR) of the transmitted light
through the shade screens was measured
around noon by a Lambda Li-185 light
meter (Table 2).
In order to screen for grass species
better adapted to growth in a wide range of
light levels that are reflective of the fluctuating light environment as experienced in
plantations, two trials were initiated to
evaluate tropical grass species for a wide
spectrum of shade tolerance. In the first
experiment, the effect of different shade
levels on the growth and performance of 12
tropical grasses was determined under
greenhouse environment. The second trial
was to compare the performance of six
tropical speciesin the field under four shade
regimes and at 6- and lO-weekly defoliation
Research Station,
intervals at MARDI
Serdang.
The pots were randomized weekly and
watered twice daily to field capacity. All
grasses were harvested to a 5-cm stubble
height on 24 February,27 April and lastly
on 7 June 1982,giving a L0-weeklyregrowth
in the first two harvests and 6-weekly
regrowth in the third harvest. After each
harvest, NPK fertilizer equivalent to 50 kg
N, 20 kg P and 50 kg I(/ha was applied.
Tiller counts were taken prior to each
harvest.
MATERIALS AND METHODS
Pot Trial Under Greenhouse Environment
The experiment was initiated in
October 1981 to assessthe performance of
12 tropical grasses (Table 1/ under four
shade levels (inclusive of a control) in a soilpot culture at Serdang. The experimental
The harvestedmaterials were separated
into leaf and stem fractions. The leaf samples
were subsampled for leaf area determination in the first and second harvests using an
electronic leaf area meter. The leaf and
stem fractions were then dried in an oven at
80"C for 48 hours and weighed for dry
226
Table 1. The 12 tropical grassesselectedfor study
Botanical name
Common name
Axonopus compressus(Sw.) Beauv.
Carpet grass
Signalgrass
B rachiaria decumbens Stapf .
Congograss
MARDI digit
Brachiaria ruziziensis Germain & Evrard
D igitaria setiv alv a Stent.
Transvaladigit
'Rumput pahit'
Digitaria decumbens cv. Transvala (Stent)
Ottochloa nodosa (Ktnth)
Dandy
Green panic
Commonguinea
Tanganyika
guinea
Tee grass
Panicum maximum var. trichoglume (Eyles)
Panicum maximum lacq.
Panicum maximum cv. Tansanvika
Paspalum conj ugatum Berg.
Setaria sphacelata var. sericea cv.
Kazungula (Schumach) Stapf. & C.E. Hubb
Setaria sphacelata var. splendida (Stapf.)
Kazungula
setaria
Splendidasetaria
Table 2. Light levels under various shade screens in the pot trial
Density of shadescreen(layers)
Shade level
% PHAR
PHAR (ME/m'?ls)
In greenhouse
I
SGO
SG1
I 350
760
2
3
SG2
SG3
460
0
215
100
56
34
18
Outside greenhouse
64
30
18
9
PHAR at full sunlight-- 2130ME/m'ls
measured2 x 2 metres. The shade levels
(Table 3) were obtained by using different
densities of shade screen mounted on a
wooden frame2 m aboveground level. The
four sidesof each main plot were covered
from the top to about 1 m from the ground
to minimize morning and evening light
transmission.
matter (DM) determination. The root and
stubble dry weights were recorded at the
end of the last harvest.
Field Trial
Another trial was conducted on a
similar soil (Tropeptic Haplorthox) at
Serdang to determine shade tolerance and
defoliation effects on the performance of six
selected tropical grassesof different growth
habits under field conditions. The six
grasses were Carpet grass, Signal grass,
Common guinea, Green panic, Tee grass
and Kazungula setaria.
All the grasseswere initially establishedfrom vegetativecuttings(3-4 tillers
per plantingpoint) and plantedat 0.5 x 0.5
m spacing.Basalfertilizerscomprising50 kg
N/ha as Nitro 26,30 kg P/ha as triple superphosphateand 50 kg l(ha as muriate of
potash were applied after planting. The
maintenancefertilizer rateswere 150kg N,
40 kg P and 100kg lUha/yr asNitro 26, triple
superphosphateand muriate of potash
respectively,and were split-appliedtwice
annually. All plots received two uniform
The experimental design was a splitsplit plot with shade as the main plot,
defoliation frequencies as the sub-plot and
the grasses as the sub-sub-plot treatment
with three replications. Each sub-sub-plot
227
Table 3. Light levelsunder the variousshadescreensin the field
Densityof shade
screen(layers)
0
I
2
J
Shade
level PHAR(ME/m2ls)
'
SFO
SF1
2 300
I 380
sF2
780
420
SF3
defoliationsat 15-cmstubbleheightprior to
of the shadetreatment,and
commencement
defoliationat 6- and l0-weeklv cuts.
in ?,1"o,1,
full sunlieht
100
60
34
18
StatisticalAnalysis
Data were subjectedto an analysisof
variancefor a split plot design in the pot
trial and a split-splitplot in the field trial.
The meanswere ranked for shade-tolerant
performance.
All plots were harvested by hand,
weighed fresh and sub-sampledfor dry
matter yield determination. The dried
sampleswere ground to pass through a 1mm meshsteelscreen,and nitrogencontent
was determined on the bulked plant tops
using Kjeldahl analysis.
RESULTS
Environmental Conditions
Pot trial
Tiller countswere taken in June 1980
and again in November 1981 from five
randomquadrats(20 x20 cm) in eachplot.
Leaf water potential of the most recently
expandedleaves of the grassesunder the
shadelevelswas determinedusing a pressure
chamber. Soil moisture was determined
gravimetricallyfrom soil coresof 0-15 cm
depth. At the end of the experiment,roots
were sampledfrom soil cores,each20 cm2x
30 cm deepwith the crown root in the centre
of the core. The soil coreswere washedand
the roots collectedand oven-driedfor dry
weight determination.
Mean daily air temperature and
relativehumidity at 9 am and 3 pm aswell as
instantaneousPHAR around noon under
the different shade screensin the greenhouseare given in Table4.
The meandaily temperatureunder the
shadescreensgenerallydecreasedby about
1oC and the mean daily relative humidity
increasedby 3% to 6Vacomparedwith the
control. Mean instantaneous
PHAR were in
the ratio of tffiVa : 56Vo: 34Vo: lSVoof the
control for the shade treatments in the
greenhouseor equivalentto 64Vo: 30Vo :
18Vo : 9Vo of PHAR in full sunlight
(outsidegreenhouse).
MeteorologicalData
Field trial
Temperature and relative humidity
were recordedby thermohydrographsplaced
in Stevensonscreensin the four shadelevels
of Replicate1. Rainfallwasobtainedfrom a
meteorologicalsite some 100 m from the
experimental site. On several cloudless
days,diurnal variationsof the PHAR of the
transmitted light under the shade levels
were measuredat hourly intervals with a
Lambda Li-185 light meter.
228
In the field trial, the environmental
conditionswere best depicted by a typical
diurnal variationin PHAR, air temperature
and relativehumidity percentagebetween8
am and 6 pm under variousshadelevelsat
Serdangon a clear day (1,0.2.82)(Figures
Ia, Ib and 1c).
The mean daily air temperatures
under the shadescreenswere also lowered
photosynthetic
Table 4. Mean daily temperaturesand relative humidity and instantaneous
quantumflux under 4 shadeintensitiesin greenhouse
Mean daily
temp. ('C)
PHAR
Instantaneous
Density shade
screen(layers)
Shade
treatment
70 PHAR
ln tull
daylrght
Quantity zo PHAR in
,
(ME/m'zls) -g r e e n n o u s e
SGO
0
1 350
SG1
SG2
SG3
I
2
3
760
460
245
100
56
34
18
64
30
18
o
Relative
humidity (%)
3pm
9am
3pm
9am
27.3
26.4
26.8
2'7.0
32.0
32.0
32.5
32.r
96
b4
96
96
67
67
70
96
PHAR : PhotosYnthetic quantum flux
Gravimetric measurements of the soil
moisture from 0-15 cm depth, and leaf
water potential of the six tropical grasses,
increasedwith shade intensity.
30
(/
:o
)
R
2
a
1
6
AR in full sunlight
- . S F 0= 1 0 0 %
- -SF l :606/c
-.SF 2 : 34%
-.-SF3=1ll%
E
t2
f/
8 1 0 1 2 1 4 1 6 1 8 2 0 2 2
am
Pm
Timc of daY
Figure1a. Diurnal variationsin air tempera'
ture under 4 shadeintensitiesin the field.
t00
Monthly rainfall at Serdang for the
experimental period could be described as
normal and favourable for plant growth
except for a short dry spell in June 1981
(Figure Id). Dry matter yield and rainfall
were not correlated but it was evident that
period of high rainfall usually coincided with
period of high DM production, particularly
at the higher irradiance levels.
PHAR in full sunlight
+SF0:100%
---sFl:60olc
:e
-SF
*SF
Establishment
With adequate water, nutrients and
favourable temperature, all the grasses in
the greenhouse showed excellent growth.
Similarly. in the field trial, the six grasses
established well from the vegetatively propagated tillers except for Tee grass. At
commencement of the shade treatments, all
pots had good growth of grasses,and in the
field, the plots comprised almost purely
planted grasses.
2:34c/c,
3 : 18%
E
.:
6t)
v
't
am
9
l1
13 15
Time of day
t7
19
2l
pm
Figure 1b. Diurnal variations in relative
humidity under 4 shadelevelsin thefield.
Tillering
by about 1'C compared with that of the
control. The mean relative humidity
increasedby 37o-7% in increasingshade
densities.Phyotosyntheticquantum fluxes
were in the ratio of l00Vo : 60Vo: 34Vo:
1.8Vofor the four shadelevels (inclusiveof
the control).
Shade generally increased the stature
of tillers (visual observation as height was
not taken), the difference being greater
between SG 0 and the other levels (SG 1 SG 3) than between the shade levels themselves. Cumulative tiller production over
the three harvests in the 12 grasses was
229
Date: 10-2-82
PHAR in full sunlight
*-.-SF0=100o/o
-.-.-SF1=60o/c
.--.SF2=347c
-SF3=l8o/o
o
tz
SF2
-b'r.,
a,,--
TJ
1
/
sF3
I
./''
.r'
7
am
,.'
9
i
/
./
ll
13
Time of day
l5
1'7
19
Pm
Figure 1c. Diurnal variations in instantaneousphotosyntheticquantumfluxes
under 4 shade levels.
500
400
300
2N
100
0
J F M A M J J A S O N D J F
l98l
1980
A S O N D J F M A
l 9u2
Figure Id. Monthly rainfall at MARDI ResearchStation, Serdangduring the experimental
period (January 1980to April 1982).
reduced significantly (P<0.01) by shade
intensity (Figure2).
The overall mean tiller number of the
12 grassesdeclinedfrom 131.5at SG 0 to
26.6 at SG 3 (Table 5/. Tiller production
also decreased(P<0.01) with each successiveharvestirrespectiveof shadeintensityin
the greenhouse.The stoloniferousgrasses
were generally higher in tiller production
acrossall shadelevels.Carpet grassranked
the highest(P<0.05) with over 162 tillers/
230
pot followed by MARDI digit (114 tillers/
pot), Transvaladigit (112 tillers/pot)and
'Rumput pahit' (100 tillers/pot). The
Panicumspp. and Signal grasswere intermediate in tillering capacityunder shade.
Congo grassand Splendidasetariagavethe
lowesttiller production (Table5).
In the field trial, the tillering response
to shadewas similar to that in the pot trial.
Tillering also declined with time and was
higher (P<0.05) for the lO-weeklycut than
the 6-weeklycut (Table6).
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Plant Parts Composition
In the pot trial, shadegreatly affected
the distribution of dry matter in the plant
parts. The root dry weight (DW) was
significantly(P<0.01) depressedby shade
levels resultingin a decreasingroot DW
percentage
of the whole plant but a higher
shoot/root ratio (Table 5 and Figure 2). The
root DW at SG 1, SG 2 and SG 3 comPrised
and6.7Vaof the control(SG0).
46.7Vo,13.3%
were higherin root
The erect grasses
DW than the stoloniferousgrasses.Setaria
spp. producedthe highestmean root DW
(13.8g/pot) at all shadelevels,followedby
Panicumspp.(8.6g/pot),MARDI digit (7.4
g/pot),Congograssand Signalgrass(4.6 g/
pot). 'Rumput pahit' (2.a glpot) and Tee
grass(2.5 g/pot), both with shallowroots,
had the lowestroot DW (Table5).
the whole plant increased with shade
intensity up to SG 2 before it declined at SG
3 (Figure 3 and Table 5).
The leaf DW reduction from SG 0 to
S G 1 , S G 2 a n d S G 3 w e r e 2 6 V o , 5 8 V oa n d
797a of the control respectively. As a consequence of the higher increase in leaf
composition of the total plant, the leaf/stem
ratio of the grasses under shading was
e n h a n c e df r o m 1 . 1 a t S G 0 t o 1 . 8 a t S G 3
(Table 5).
The high yielding grasses, namely
Common guinea and Tanganyika guinea,
produced significantly (P<0.01) the highest
total leaf DW (22.0 g/pot) than the other
grasses (Table 5). This was followed by
MARDI digit (19.7 gipot), Green panic and
Signal grass (13.9 g/pot). Carpet grass
averagedabout 8.9 gipot and Tee grass 7.7
g/pot. Although these two grasses were
lowest in leaf DW, they were ranked fourth
and fifth respectively at SG 3. Transvala
digit and Congo grass were the poorest
yielders in leaf DW (< 1.0 g/pot) at SG 3.
In the field environment,root DW
responsesto shadeintensitywere similar.
Ten-weekly defoliation produced higher
(P<0.05) root DW than the 6-weeklycut
(Table6).
Leaf Area and Specific Leaf Area
The stem bW dectined significantly
(P<0.01) with increasingshade intensity
(Figure 3) but stem DW percentage of
whole plant increased slightly until it
declined at SG 3 (Table 5) except for
Transvaladigit, MARDI digit, Tee grass
and 'Rumput pahit' which had reductionin
stem DW percentageat all shadelevels.
Overall mean reductionsin stem DW
from SG 0 to SG 1, SG 2 and SG 3 were
33Vo,70Voand 87Voof that of the control
(SG 0). Surprisingly,
Greenpanic(16g/pot)
and Transvaladigit (15 g/pot) emergedthe
highest in stem DW, followed closely by
Signalgrass(14 dpo|. Commonguinea(12
g/pot)rankedfourthand'Rumputpahit'(l I
g/pot) was fifth. The stoloniferousgrasses
like Carpet grass, and Congo grass were
lowestin stem DW (Table5).
Leaf DW declined with increasing
of
shade(P<0.01)but leaf DW percentage
./-J1
Leaf area usually increasedfrom SG 0
to SG 1 and then declined non-significantly
with further shade increase except at SG 3
where leaf area was significantly (P<0.05)
lower than those at the other shade levels
(Figure 4/. Common guinea produced significantly (P<0.05) the highest leaf area (32
'Rumput p^ahit' and
dm2/pot) followed by
Green panic, each with 26 dm'lpot and
Tanganyika guinea and Signal grass, each
with 24 dm2/pot (Table 5).
In the field trial, the leaf area index
(LAI)
increased non-significantly with
shading but declined at SF 3 (Table 6,). As
expected, Common guinea produced the
highest LAI while the stoloniferous grasses
viz. Tee grass and Carpet grass were the
lowest.
The specific leaf area which was the
ratio of leaf area to leaf DW presents a
measure of leafiness of a srass under shade
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Sp8
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Sp7
J
Spl-Carpetgrass
Sp2-Signalgrass
Sp3-Congograss
Sp4-MARDIdigit
Sp5-Transvaladigit
Sp6-'Rumputpahit'
Sp7-Greenpanic
Sp8-Tanganyikaguinea
Sp9-Commonguinea
Sp l0 - Tee grass
S p l l - K a z u n g u l as e t a r i a
S p 1 2 - S p l e n d i d as e t a r i a
Shade levels (o/c PHAR in greenhouse)
Figure 4. The influence of shading on leaf areaproduction of 12 tropical grassesgrown
undergreenhouse
environment.
as an adaptivesensitivityto reducedlight.
Specificleaf area increased(P<0.01) with
shading but was negatively correlated to
DM yield(r : -0.96). 'Rumputpahit'and
Tee grasswere highestin specificleaf area
comparedto the Panicum spp. and Digitaria
spp. (Table 5). Nevertheless,specific leaf
area increasewas greatestin the Panicum
spp. (datanot shown).
centageof the plant tops acrossthe grasses
were30.4Vo, 23.3Vo19.jVo andl6.lVo at SG
0, SG 1, SG 2 and SG 3 respectively.
CumulativeDM yieldsof the plant topsover
the three harvests among the grassesat
different shadeintensitiesare illustratedby
their regression curves (Figure 5) and
regressionequations(Table 7).
Dry Matter Production
Under the greenhouseenvironment,
the DM yield of the 12 tropical grasses
declinedsignificantly(P<0.01) with shade
intensity (Table 5,). The mean DM per-
236
Overall mean DM yield of the plant
tops in the 12 grassesat SG 1, SG 2 and SG
3 were 7LVo,37Vaand 18Vorespectively
of
that obtainedin control (SG 0). At SG 0,
Signal grassproduced the highestcumulative DM yield (60.8 g/pot) followed by
Tanganyikaguinea(51.6 g/pot), Transvala
Treatment
Shadc.
''
Grassess''
G r a s s e sw i t h i n s h a d e * "
Shadewithin grasscs"'"
e60
bo
Spl-Carpetgrass
Sp2-Srgnalgrass
Sp4-MARDIdigit
Sp5-Transvaladigit
Sp6-'Rumputpahit'
Sp7-Greenpanic
LSD (0.01)
2.90
3.73
7.46
7.61
guinea
Sp t3- Tanganyika
Sp9-Commonguinea
Sp l0 - Tee grass
Sp ll - Kazungulasctaria
sctaria
Sp l2 - Splendida
,/
_-.-.-'-'-'-'
SP'i
-.. --y':'*- 1; - --.*-** - -
] ) u
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S h a d e l e v e l s( ? ; P H A R i n f u l l s u n l i g h t )
Figure 5. Regressioncurves of the effect of shadingon the cumulativedry matteryield of
grownunder greenhouseconditions. Species 3
the top growth in 11 tropical grasses
(Congo grass)was omitted.
Table 7. Regressionequationsfor dry matter yield of the tropical
grassesas affectedby shade
Cumulativedry matter yield (g/pot)
Regressionequation
Carpet grass
Signal grass
MARDI digit
Transvaladigit
'Rumput pahit'
Green panic
Common guinea
Tanganyikaguinea
Tee grass
Kazungulasetaria
Splendidasetaria
Y=
Y=
Y=
Y=
Y=
Y=
Y=
Y=
Y:
Y=
Y=
6.34+ 0.325- 0.0009s'z
- 0.001652
-1.62+ 1.085
-13.46+ 2.375- 0.0021s'z
-11.5 + 1.535- 0.0089s'z
-0.,10+ 0.915- 0.004752
-3.12+ 2.015- 0.02Sr
7.30+t.37S-0.011s'?
7.87+ r.53S- 0.0145s':
2.57+ 0.525- 0.000952
- 0.0217s'?
-12.11+ 2.0365
-6.75 + 1.435- 0.0105s':
Y : Yield, S : Shadelevel (Va PHAR outsidegreenhouse)
*Significant(P = 0.05)
'*Significant (P : 0.01)
zJt
Correlationof
determination(12)
0.71'.
0.98"
0.93.*
0.93"
0.93*'
0.69"
*
0.90*
0.81"
0.96'0.60'
0.92"
of dry matter. Carpet grass performed
poorly at SF 0 but its DM yield increasedto
7.9 tlhalyr at SF 1 and 7.4 tlhalyr at SF 2.
Tee grass behaved in similar way under
shade but was less persistent and less productive.
digit (49.6g/pot)and MARDI digit (49.5g/
pot).
The indigenous
grasses
namelyCarpet
grass(21.7g/pot)and Tee grass(32.3glpot)
were the lowestyieldersat SG 0. However,
under heavyshade(SG 3), they rankedon
par with Signalgrassbut were higheryielding than the Setariaspp. and Digitaria spp.
(Figure 5).
Plant Survival and Botanical Composition
At the end of the pot trial, all grasses
in the three replicatessurvived at SG 0 and
SG 1 but under heavy shade (SG 3),
mortality of grassesin all the replicateswas
evident. Green panic, Common guinea and
Carpet grass were the only three grasses
which had 100% survival in all replicatesat
SG 2 and SG 3. Tanganyika guinea had
700Vo mortality in one replicate at each
shade level, SG 2 and SG 3, while Signal
grass and 'Rumput pahit' each had 100%
mortality in two replicates at SG 3. Congo
grass died out completely in all the
replicates at SG 2 and SG 3. The Setaria
spp., Digitaria spp. and Tee grass did not
survive in all replicates at SG 3, indicating
poor tolerance of these grasses to heavy
shade.
At moderateshadelevels(SG 1 and
SG 2), the Panicumspp.continuedto be the
bestyieldersparticularlyTanganyikaguinea
and Common guinea. This was closely
followedby MARDI digit, However,Signal
grassshoweda markeddeclinein DM yield
from SG 1 onwards.Transvaladigit performedpoorly undershadeand wasranked
11th at SG 2 and SG 3. MARDI digit
yieldedpoorly at SG 3 while the indigenous
grassescontinuedto be poor in DM production.Nevertheless,
the indigenousgrass
persistedwell at SG 3, especiallyCarpet
grassbut not'Rumput pahit'.
In the field trial, the annualDM yields
of the six grasses
at 6- and 1O-weekly
cutting
intervalsin four shadelevelsare shownin
Figure6. CumulativeDM yield was highest
at 6-weeklycut comparedto 10-weeklycuts
for Carpet grass,Green panic, Tee grass
and Kazungulasetaria.In contrast,Signal
grass and Common guinea maintaineda
higherDM productionunder the 10-weekly
cut.
Across all the shade levels, Signal
grasswasthe highestyielderat both cutting
frequencieswith 16.1 tlhalyr at 6-weekly
cuts and 19.3 tlhalyr at 1O-weeklycuts.
Commonguineaproducedan averageyield
of 15.1tlhalyr at 6-weeklycutsand 77.6 tlhal
yr at 10-weekly cuts. Kazungula setaria
yielded about 9 tlhalyr for both cutting
intervalswhile Green panic producedabout
6 tlhalyr and was sensitiveto 6-weeklycuts
under heavyshade(SF 3).
The two indigenousgrasses,Carpet
grassand Tee grass,were the lowestyielders
In the field, the botanical composition
(as DWTo) of the six grasseswere almost
700Vopure in the swards at commencement
of trial. After 28 months of defoliation, the
planted grass composition declined with
shade intensity (Table 6).
However, at 10-weekly cuts, the
botanical composition of the planted grasses
was generally higher than that of the
6-weekly cuts. On the other hand, Carpet
grass increased tremendously in botanical
composition with shade level, indicating its
adaptation to lower irradiance. At 6-weekly
cuts, Carpet grass composition increased
from 267o at SF 0 to almost 100% at SF 3
while at 10-weeklycuts, its composition was
enhanced to 96Vo at SG 2 but declined to
5 2 V oa t S G 3 .
Botanical composition of Signal grass
declined from I007o at SF 0 to 50Vo in the
6-weekly cuts and to 75Voin the 10-weekly
23n
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239
grassand Green panic were the lowest of all
the grassesin shade tolerance at SG 0.
cuts at SG 3. Common guinea and Kazungula
setaria also showed similar declines with
shade intensity. Green panic, not being
persistent at 6-weekly cuts, died out under
heavy shade(SG 3). Tee grasswas generally
poor in botanical composition at all shade
levels and at both cutting intervals, reflecting its instability in such environmental and
managementconditions.
At moderate shade (SG 1), both
Tanganyika guinea and Common guinea
becamethe top two in shadetolerancewhile
MARDI digit was ranked third, followed by
Green panic and Signal grass. Poorest performance was from Congo grass and Tee
grass, but Carpet grass improved to rank
number nine.
Generally, the weed component
increased with shading. The weed species
were mainly Nephrolepis biserrata, Lygodium
flexuosum, Imperata cylindrica, Phymatodes
scolopendria, Mikania cordatq, Melastoma
malabathricum and Lantana camara.
At SG 2, Common guinea and
Tanganyika guinea continued to rank at the
'Rumput pahit'
top in shade tolerance with
and Green panic being ranked third. Congo
grass, Transvala digit and Tee grass were
the lowest in shadetolerancerating at SG 2.
Overall Assessmentof Shade Tolerance
Under heavy shade (SG 3), the
Panicum spp. again ranked top with Carpet
grass following after. Signal grass and Tee
grass were ranked fifth and seventh respectively. The lowest were from Congo grass,
Transvala digit and Kazungula setaria.
There was great similarity in the
responsesto shade of the grassesin the pot
trial and in the field. N{ost of the agronomic
attributes responded in a similar pattern to
shading. Correlation coefficients between
the DM yield, tillering and root dry weight
of the pot trial with those of the field
e x p e r i m e n tw e r e 0 . 9 2 , 0 . 9 7 a n d 0 . 8 5 r e s p e c tively (significant at P : 0.01). Hence, the
overall assessmentof shade tolerance in the
grasseswas based on the pot trial results.
Nitrogen Content
The percentage of nitrogen in the
dried forages of the six tropical grasses
increased significantly (P<0.01) with
increasingshade intensity. The grasseswere
also significantly different (P<0.01) from
each other in N content (Table 6). Kazungula
setaria and Carpet grass had significantly
higher (P<0.01) nitrogen content than the
other grasses.Green panic had the lowest
nitrogen content.
The overall comparison of the grass
performance under various shade levels was
by rank comparison and mean rank. If all
best to
the grasses were ranked (1
12 : worst, with respect to each of the
desirable attributes), the grasseswere thus
selectedto ascertainthe best compromising
attributes for tolerance to different shade
intensities. The best grassesare those that
have the lowest mean rank.
The shade tolerance of the grasses
ranked from the nine agronomic attributes
at four shade levels is illustrated in
Appendix 1. Of the 12 grassesstudied, the
Panicum spp. emerged the best at all four
shadelevelsGable 8/. At SC 0 (control).
Signal grass ranked first followed by
digit.
Common guinea and MARDI
grass
Tee
were
Tanganyika guinea and
respectively.
Carpet
ranked fourth and fifth
There were also significantdifferences
(P<0.01) in defoliation intervals on nitrogen
content as well as defoliation x grassinteraction (Table 6). The 6-weekly cuts gave
higher nitrogen content in dry matter than
t h e 1 0 - w e e k l yc u t s .
2.10
DISCUSSION
From data on all the agronomic attributes measured in the 12 grassesfor shade
tolerance, many of the grassesbehave like
sun plants. All seemed to make the best
Table 8. Ranking of 12 tropical grassesgrown under 4 shadelevelsunder
greenhouse
environmentfor overallshadetolerancebasedon the meanrank
scoreof 9 agronomicattributes
Shade levels (Eo PHAR in greenhouse)
Ranking
sGo (r00)
sG 1 (s6)
sG 2 (34)
s G3 ( r 8 )
I
Signal grass
Tanganyika guinea
Common guinea
Tanganyika guinea
2
3
4
5
Common guinea
Common guinea
Tanganyika guinea
Green pantc
MARDI
MARDI
Common guinea
Tanganyika guinea
Green panic
Green panic
'Rumput pahit'
Tee grass
'Rumput pahit'
Signal grass
MARDI
Sptendida setaria
Signal grass
Signal grass
'Rumput pahit'
7
Splendida setaria
Tee grass
Transvala digit
Kazungula setaria
'Rumput pahit'
Carpet grass
I
9
10
Kazungula setaria
MARDI
Congo grass
Carpet grass
Splendida setaria
Splendida setaria
Kazungula setaria
Transvala digit
Tee grass
Kazungula setaria
11
12
Carpet grass
Tee grass
Transvala digit
Transvala digit
Green panic
Congo grass
Congo grass
Congo grass
b
digit
digit
digit
Carpet grass
digit
enable tropical grassesto fully exploit the
incoming radiation in the full sunlight
(EnrxseN and WutrNnY, 1981).
growth at or close to full sunlight except for
Kazungula setaria,MARDI digit and Green
panic with projected optimum DM production around 50% full sunlight. The mean
yield reductions across the grasses were
28.77o, 63.3% and 82.47o of that of the
control (SG 0) f.or a 44Vo, 66Vo and 827o
PHAR
reduction in the sreenhouse
respectively.
Water stress could limit the general
growth of the grassesin full sunlight, as
partially shaded plants were under less
water stress (Table 5). The leaf water
potential of the six grassesunder shadewere
generally higher than those in full sunlight
(control). Soil moisture under shade was
higher, possibly due to lower evapotranspiration brought about by reduced
solar radiation on the shadedplants. Hence,
maximal yields were achieved under partial
shade in a low nutrient input system.
Tillering capacity and leaf, stem and
root growths were greatly depressed by
shade intensity in both experiments. In the
field experiment, a similar PHAR percentage reduction at higher irradiance also
resulted in DM yield reduction but the
degree of reduction was not commensurate
with the intensity of PHAR reduction
especiallyat the higher light level (from SF 0
to SF 1). By contrast, two grasses,namely
Carpet grass and Green panic, produced
maximal yields under partial shade (SF 1
and SF 2). It appeared that there were
constraints that militated against productivity and the realization of maximal
yield potential in full sunlight.
Of the 12 grasses evaluated, the
Panicum spp. and Signal grassranked top in
DM production at the various shade intensities in both experiments. The l0-weekly
cuts of the field trial produced a higher
(42%) overall DM production than the 6weekly cuts at SF 3. Nonetheless, Signal
grassoutyielded the other grassesat SG 0 in
the pot trial and at full sunlight in the field.
Average DM yields of 21 and 24 tlhalyr at 6'
and 10-weekly cuts were obtained respectively. Such yields were comparableto those
recorded in earlier cutting experiments at
Serdang (WoNc, 1980).
The current fertilizer rate of 150 kg N/
halyr could be inadequate to support
maximum yield potential as a rate of 365 kg
N/ha/yr has been quoted as insufficient to
141
Even at moderate shade (SF 1), the
yield of Signal grasswas still high (20-24 tl
haiyr). At SF 2, 13-16tlha/yr were obtained.
Despite the yield decline with shade
intensity, Signal grasscontinued to show its
superiority in DM yield over the other
grassesexcept for the Panicum spp. even at
S F 3 . H o w e v e r . u n d e r h e a v y s h a d e( S F 3 ) .
its growth, vigour and persistence were
reduced as indicated by the low tillering
capacity,marked leaf area decline, low root
DW and finally poor botanical composition
in the swards especiallyunder the 6-weekly
cutting management. Poor performance of
Signal grass under heavy shade had also
been reported in Solomon Islands (Snatru
and WHrreMAN, 1983) and at Serdang
(CHrN and BoNc, 1984). Its sensitivity to
heavy shade and at short cutting frequency
could thus only favour its use in moderate
s h a d ea n d u n d e r l a x c u t t i n g o r g r a z i n g .
Common guinea, like Signal grass,
maintained high DM yield across all shade
levels,with 21 -28 tlhalyr for both 6- and 10weekly cuts iespectivelyat SF 0, 17-20 t/ha/
yr at SF 1 and SF 2, 8-10 tlhalyr at SF 3.
The prolonged cutting (1O-week) interval
enhanced DM yield, tillering and botanical
composition in swards at SF 3.
Green panic performed poorly in the
field experiment despite its better growth
under shade. Its average yield was about
one-third that of Signal grass or Common
guinea. It was rather sensitive to 6-weekly
cuts under heavy shade. Its poor performance could be attributed to its poor
adaptation to the humid tropics.
Tanganyikaguinea in many respects
was similar to Common guinea in shade
responsesexcept its ranking was better than
Common guinea under heavy shade. CHeN
and Bonc (1984) reported best growth of
Tanganyika guinea at 4-monthly cutting
interval under a closedoil palm canopy. The
potential of this grassunder shade deserves
further attention.
The genus, Panicum has been known to
have species adapted to shaded habitats
1 1')
(Bnowr, 1977). Good growth from Panicum
spp. under light shade had been reported
and
(SaNrHtnesecARAM, FenotNeNoez
GooNnsercenn, 1969). In this study, even at
SF 3, the DM yield was about one-third that
of the control and two to three times more
than those of the indigenous grasses,
indicating that the Panicum spp. were still
by far the higher yielding and better adapted
grassesunder shade. This could be attributed to the erect habit of the grassas well
as the morphological adaptive changes in
their shoot/root ratio and larger leaf area
WtlsoN and
under shade (Luolow,
He,slEHunsr, 7974). Furthermore, WoNG
and WtlsoN (1980) indicated that the
stature of a Panicurn sp. under shade was
taller and leaf area well-distributedthroughout the canopy, resulting in low light
extinction coefficients.All these could thus
contribute to its better performance than
the other grasses under heavy shade. Its
ability to persist.undergrazingin plantation
had been proven (Surnt, RosvewRrt and
MusnoorN 1982). The more prostrate
grassessuch as Carpet grass and Tee grass,
were the lowest yielders at all shade levels
but they were ranked fourth and seventh
respectively, at SG 3. They generally
preferred shorter cutting intervals (6-weekly
cuts). However, under partial shade, Tee
grass in the field experiment was not as
aggressive in growth as Carpet grass.
Although both specieswere highlighted as
persistent grasses under heavy shade
( < I 5 % s u n l i g h t )b y C H e Na n d B o N c ( 1 9 8 4 ) ,
DM production of Tee grass was generally
40Vo lower than that of Carpet grass in the
field trial. No Tee grass plants survived ai
SG 3 in all three replicates in the greenhouse. Even in the field, its botanical
composition was low (<I07o) whereas, in
the case of Carpet grass, growth improved
with shade. Higher botanical composition in
a sward was obtained at 6-weekly cuts and
under moderate to heavy shade.
In Solomon Islands, Carpet grass was
also found to be the most common grass
under coconut (Svnu and WuIteueN,
1983). It was not surprising that at SF 3, its
tents, ranging from 1.46% to 2.44Vo, wete
considerablyhigher than those reported by
WoNc (1980) for grassesfertilized at 400 kg
N/ha/yr at Serdang.The enhancednitrogen
content of the shaded grassescould be an
advantagein otherwise low-nitrogen tropical
grassesreceivinglittle nitrogen fertilization.
Increased nitrogen content in the tropical
grassesunder shading had also been recorded
e l s e w h e r e( E n r r s e N a n d W H I T N E v , 1 9 8 1 ;
SvtrH and WHtrevnN, 1983).Nevertheless,
the nutritive value of the grassesneedsto be
studied as forage quality could be reduced
by shade (WImoN and WoNc, 1982).
DM yield was at least 307o of that of the
control and thus was a favoured grass for
intense shade. Its tillering was the highest
among the grasses assessed.Due to its
shallow rooting system,Carpet grassis thus
prone to environmental stressand hence it
performed better under partial shade.
'Rumput pahit' vgasalso noted for its
luxuriant growth under moderate shade but
did not persistwell in SG 3, where only one
replicate survived. Its rapid decline in leaf
area with shading and low root DW probably
contributed to its poor shade tolerance. It
was ranked sixth at SG 3.
Agronomic Implications
With the exception of the Poor Performance of Kazungula setaria at SG 0, the
Setaria spp. in the pot trial were generally
average in their responses of DM yield,
tillering, specific leaf area and leaf area to
moderate shade. Under SG 3, they were
among the least shade-tolerant grasses
(Table 5).
The results indicate that improved
grasses,particularly Panicum spp. and Signal
grass, have maximum potential in forage
production during the juvenile stages of
plantation crops and could be further
extended for utilization in plantations until
the light levels (abour30%) become a major
limiting factor to their DM production.
Below this light level, indigenous grasses
such as Carpet grasscould take over through
weed invasion until total solar radiation is
cut off by the closed canopy.
The Digitarlc spp. generally grew well
at SG 0 but Transvala digit was sensitiveto
shading, resulting in poor ranking at SG 2
and SG 3 (Table 8). By contrast, MARDI
digit remained good in growth up to SG 2,
but produced poorly in DM Yield and
tillering at SG 3. Similar responseswere also
reported in Mealani digit in Hawaii where
yield was markedly depressedunder heavy
shade (27% sunlight) (Enlxseru anc
WHITNEy, 1981). The forage potential for
MARDI digit would be for utilization under
moderate shade only.
The nitrogen contents in the grasses
were above the critical level (74lo crude
protein) below which DM intake of the
grasses would be affected (Mtlrono and
MrNSoN, 1966). In fact, nitrogen content
increasedwith shade intensity, with 6-weekly
cuts giving a higher percentage than the
l0-weekly cuts in all the six grassesassessed
(Table 6).
Tropical grassesare generally known
for their low crude protein content and the
shadedgrasseswith enhancednitrogen con-
_ +-l
Although these trials were carried oul
under artificial shade without competitive
effects of the establishedplantation crops,
the findings on the spectrum of shade
tolerancein the grassescould be adopted for
further verification in plantations. Nevertheless, the grasses identified had been
shown in field trial elsewhereto be suitable
for integration with plantation crops (Surnl
et al., 1982).
Since the DM yield declined with
shading,the carrying capacityof the grasses
under shade would also decrease.Based on
the DM production of the grassesunder
various shade levels. and the estimated DM
intake of 9 kg DM per cattle per day, the
projected stocking rate of the promising
grasseswould be about 4 heads/haat 60c/c
3 heads/haaI 34o/c:and 2 headslha at 19%
light. However, the loss of ground spaceby
the standing tree crops should be taken into
consideration in the extrapolation of the
possible carrying capacity of the shaded
pasture.
In view of the declining DM yield with
shade and the sensitivity of improved grasses
to defoliation under shade, careful management of the grassesis necessaryto ensure
the continual DM productivity and persistence of the grasses.Limited grazing at low
stocking rates or lenient cutting would be
recommended to ensure that consumption
by the cattle per unit area does not exceed
DM productivity under the varying shade
l e v e l s . U n d e r s u c h c i r c u m s t a n c e sv, a r y i n g
the stocking rate according to the shade
intensity would be the best approach to
promote efficient utilization of the available
pasturesin the plantation as well as to avoid
damage to the main crops, especiallyduring
the juvenile stage, as often, feed shortageis
the main causeof such destruction.
Finally, the need to look at other
shade-tolerant species (ferns) at low light
levels (<10% sunlight) besidesgrassesand
legumes as possible feeds for livestock
deservesimmediate attention.
ACKNOWLEDGEMENTS
The authors wish to express their
appreciation to the field staff for their
assistanceand to Mr. Ahmad Shokri Hj.
Othman for statistical analyses and the
Central Analytical Services for nitrogen
analvses.
ABSTRACT
S h a d e t o l e r a n c e o f l 2 t r o p i c a l g r a s s c sw a s e v a l u a t c d u n d e r a r t i f i c i a l s h a d e i n g r e e n h o u s e
c o n d i t i o n sw i t h t r a n s m i s s i o no f 6 4 7 a . 3 0 % . 1 8 c / ca n d 9 c i p h o t o s v n t h e t i cq u a n t u m f l u x ( P H A R ) o f t h e
f u l l s u n l i g h t f b l l o w e d b v a f i e l d e x p c r i m e n t t o a s s e s st h e p e r f o r m a n c eo f s i x s e l e c t e dg r a s s e su n d e r l i g h t
t r a n s m i s s i o no f 1 0 0 ' u Z( c o n t r o l ) . 6 0 l c , 3 4 c r c a n d 1 8 9 i o f P H A R o f t h e f u l l s u n l i s h t a n d d e f o l i a t e d a t 6 a n d 1 O - w e e k l yc u t t i n g i n t e r v a l s .
I r l t h e g r c e n h o u s et r i a l . s h a d i n gs i g n i f i c a n t l v( P < 0 . 0 1 ) r e d u c e d t i l l e r p r o d u c t i o n .
c u m u l a t i y ed r y
matter vields of shoot. leaf, stem. stubble and root, but enhanced specific
lcaf area. Increased
p a r t i t i o n i n g o f d r y m a t t c r t o t h e l e a f c o m p o n c n t a t t h e e x p e n s eo f r o o t
u n d e r s h a d er e s u l t e d i n h i g h e r
s h o o t / r o o t a n d l e a f / s t e mr a t i o s . M e a n d r v m a t t e r v i e l d r e d u c t i o n a c r o s st h e g r a s s e sw c r e
2g.7c/r.633%
and 82.4c/cof that of the control for a 4411. 66lt and 827o reduction in PHAR in
the greenhouse trial.
The best shade-tolerant grasses were Panicum marimum, P. maximum cv. Tanginyika
, Digitaria
setivalva an<1Brachiaria decumbens. The least shade-tolerant species were
Setaria sphacetita cv.
Kazungula, Digitaria decumbenscv. Transvala and B. ruziziensri. However, at
dense sfraae 1lA PURR
transmission). the indigenous grasses, Paspalum conjugatum and Axonopus
compressus were ranked
s e v e n t ha n d f o u r t h r e s p e c t i v e l y .
In thc field experiment, P. maximum and B. decumbens were the best yielders across all shadc
levels. Mean dry mattcr (DM) yield reduction of the six grasseswere 23.lVc and 3j .6o/cof the control for
a 667c and tl2% PHAR reduction in full sunlight. Axonopus compressus and P. maximum var.
trichoglume produced higher DM at moderate shade under both defoliation intervals. The 10-weekly cut
g a v e h i g h e r D M y i e l d a n d t i l l e r p r o d u c t i o n u n d e r s h a d e i n t h e e r e c t g r a s s e s ,w h i l e t h e 6 - w e e k l y
cut
resulted in higher yield for the prostrate grasses.viz. A. compressrs and p. conjugatum.
P r o l o n g e d c u t t i n g i n t e r v a l sw e r e p r c f e r r e d u n d e r h c a v v s h a d et o c n h a n c c s u r v i v a l a n < jb o t a n i c a l
compositionof the sown grassesT
. h e n i t r o g e n c o n t e n t o f t h e g r a s s e sg e n e r a l l y i n c r e a s e dw i t h s h a d i n g
a n d u n d e r s h o r t e r c u t t i n g i n t e r v a l . L o w - y i e l d i n g g r a s s e s ,n a m e l y S . s p h a c e l a t ac v . K a z u n g u l a a n d , 4 .
compressus, had higher nitrogen contents while P. maximum var. trichoglume had the lowest.
T h e s i g n i f i c a n c e o f t h e f i n d i n g s w a s d i s c u s s e di n r e l a t i o n t o p a s t u r e m a n a g e m c n t u n d e r
plantations.
REFERENCES
BnowN, w.V. (1977). The Kranz syndrome and its
subtypes in grass systematics.Mem. Torrey Bot.
Club 23, 1-97.
tropical foragesunder the closedcanopy of oilpalm. L Grasses. MARDI Res. Bull. 11.21g63.
Csrn. C.P. and BoNc, J.l. (1934). Performance of
C S E N .C . P . . C H e N c , K . C . . A : r r , S . S .a n d H A S S A NW
.
-)t
I
-++
S u K R I ,M . , R o s u e w r t t , O . a n d M u s r o o t N , K . ( 1 9 8 2 ) .
Integration of Kedah-Kelantan cattle with oilpalms - A preliminary repotl. MARDI Res.
Bull. 10,436-41.
(1978). Pasture and animal production under
five-year-old oil palms at Serdang. Proc.
Seminar on Integration of Animals with Plantation Crops, Kuala Lumpur, 1978' pp. 179-92'
E R T K s E NF, . I . a n d W s n N e v , A . S . ( 1 9 8 1 ) . E f f e c t o f
light intensity on growth of some tropical forage
species. L lnteraction of light intensity and
nitrogen fertilization on six forage grasses.
T H o u r s D . ( 1 9 7 8 ) . P a s t u r e sa n d l i v e s t o c k u n d e r t r e e
crops in the humid tropics. Trop Agric', Trin.
55,39-44.
Agron. J. 73,427-33.
W H I T E M A N ,P . C . , B o n o n o u E z , M . a n d R n N r c o u , E '
(1978). Shade tolerance in four tropical pasture
legume species. Proc. l2th Int. Grassld. Congr.,
Moscow, 1978, pp. 402-10.
LuDLow. M.M., Wrr-soN, G.L. and Hgslesunsr,
M.R. (1974). Studies on the productivity of
tropical pasture plants. V. Effect of shading on
growth, photosynthesis and respiration in two
grassesand two legumes. Aust. J. agric. Res.25,
W r L s o N ,J . R . a n d W o N G , C . C . ( 1 9 8 2 ) .E f f e c t s o f s h a d e
on some factors influencing nutritive quality of
Green panic and Siratro pastures. Aust. J. agric.
425-33.
Res.33.937-49.
Mrlrono, R. and MINsoN, D.J. (1966). Intake of
tropical pasture species. Proc. 9th Int. Grassld.
Congress, Sao Paulo, 1965, pp.815-22.
. r o d u c t i v i t y a n d c h e m i c a lc o m p o WoNc C.C. (.1980)P
sition of twenty improved tropical grassesin the
h u m i d t r o p i c s . M A R D I R e s .B u l l . 8 , 1 6 3 - 7 3 .
SexrstnlsecnRAM, K., FenolNnNoez, D.E'F. and
GooNnsexpnr, G.C.M. (1969). Fodder grass
cultivation under coconut. Ceylon Cocon. Plrs.
Rev.9. 1ffi-7.
WoNc, C.C. and WtlsoN, J.R. (1980). Effects of
shading on the growth and nitrogen content ot
Green panic and Siratro in pure and mixed
swards defoliated at two frequencies. Aust. J.
agric. Res.31,269-85.
S M I T H ,M . A . a n d W u t r E u r N , P . C . ( 1 9 8 3 ) . E v a l u a t i o n
of tropical grasses in increasing shade under
coconut canopies. Expl. Agric. 19,153-6t.
Acceptedfor publicationon 18th May, 1985'
245
Appendix 1. The overall mean and agronomicattribute ranking for the 12 tropical grasses
grown under4 shadelevelsin a greenhouse
Shadelevel
SLA
Dry matter
Leaf area
Root
sG 0 (100%PHAR)
Carpetgrass
J
2
10
3
5
8
12
2
Green panic
9
l l
Common guinea
8
Signal grass
7
Congo grass
4
MARDI
digit
Transvala digit
'Rumput pahit'
12
10
8
Leaf
ratio
2
9
5
2
2
4
7
6
8
4
1
7
t2
'7
1
1
Shoot/roor Leaflstem
Stem
2
0
1
1
0
1
I
11
9
3
9
8
10
6
4
5
6
1
2
7
9
4
2
t2
10
o
3
Tillering
DM
yield
1
Mean
rank
t2
8.22
7
1
4.44
10
9
7.22
J
3
5.22
2
3
6.78
5
I
6.67
1t
6
8.33
8
2
4.78
Tanganyika
11
7
3
3
9
8
1
o
5
5.89
1
4
12
11
4
3
10
4
l0
6.55
setana
5
9
2
7
1l
It
5
o
11
7. 7 8
Splendida setaria
o
6
1
5
10
8
12
7
6.78
Carpet grass
4
1l
8
Signal grass
o
5
Congo grass
5
12
l0
9
o
5
Transvala digit
'Rumput pahit'
o
12
7
1
2
Green panic
8
8
l0
1
t1
3
t
2
9
lr
setaria
7
1
Splendida setaria
3
guinea
Tee grass
Kazungula
6
sG | (s6%PHAR)
MARDI
digit
Common guinea
1
8
1
2
4
1
11
7. 1 1
0
6
4
2
8
9
6
6.22
8
8
12
o
12
9
8.78
1
9
7
1
2
4
5.22
4
12
2
8
7.44
1
1
2
12
10
10
I
9
4
10
6.56
6
4
1
6
11
8
2
6.m
+
3
)
8
3
5
J
4.O/
o
9
I
6
1
4.55
12
11
3
l0
7
t2
8.56
3
5
7
10
5
6.33
7
3
7
10
1
11
5
11
7
6.22
Tanganyika
guinea
Tee grass
z
Kazungula
SLA = SpecificLeaf Area,
Rankinq:1 = Best and 12 = Worst
246
Appendix 1. Contd.
Shade level
SLA
Dry matter
Leaf area
Root
Leaf
Stem
Shoot/root Leaf/stem Tillerine
ratio
ratio
DM
vield
Mean
rank
SG 2 (34Vo PHAR)
Carpet grass
Signal grass
Congo grass
MARDI
digit
Transvala digit
'Rumput pahit'
2
3
12
10
7
5
12
2
6
ll
I
Green panic
7
Common guinea
9
3
4
,l
5
8
ll
l0
1
e
ll
5
3
1
t2
12
12
t2
3
2
9
a
8
11
10
5
J
9
6
4
2
A
7
4
1
ll
t)
2
1
2
0
5
3
4
10
8
'7
6
7
9
12
1
3
2
12
8
6
1
o
12
2
9
s
t2
4
II
6
3
2
6.33
5.56
12.00
4.56
8.44
4.78
4.78
3.78
1
9
5.00
7.78
7
8
7.22
7.67
6
4
12
r0
ll
7
3
2
5.33
6.11
1 0 .11
6.88
9.6'7
6.22
3.78
3.88
1
4
3.78
6.55
9
8
8.ll
7.00
Tanganyika
gulnea
Tee grass
11
o
A
t0
4
1
3
0
Kazungula
8
setafla
Splendida setaria
8
o
1
5
0
'l
7
o
6
6
7
1l
sG 3 (18% PHAR)
carpet grass
a
b
9
4
4
8
8
Signal grass
1
9
6
Congo grass
11
11
6
11
5
2
8
6
9
2
12
t2
5
5
11
6
10
6
a
2
5
3
6
I
1
2
7
10
3
z
4
12
MARDI
digit
Transvala digit
'Rumput pahit'
Green panic
Common guinea
1
0
1
2
Tanganyika
gulnea
Tee grass
t
5
11
7
11
2
8
'7
J
I
8
3
5
l1
4
5
o
10
10
Kazungula
setaria
7
10
3
Splendida setaria
3
7
3
1
0
7
1
2
9
SLA = SpecificLeaf Area.
Ranking: 1 : Best and 12 : Worst.
", ,11
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