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Biodiversity of Soil Microbes from Rhizosphere at Wamena
Biological Garden (WBiG), Jayawijaya, Papua
SRI WIDAWATI
, SULIASIH, H.J.D. LATUPAPUA, ARWAN SUGIHARTO
Microbiology Division, Research Center of Biology, Indonesian Institute of Sciences, Bogor 16002
Received: 30 November 2004. Accepted: 26 December 2004.
ABSTRACT
The isolation, identification and population of soil microbes from rizosphere at WBiG had been done in the Soil Laboratories Microbiology,
Microbiology Division, Research Center of Biology, Indonesian Institute of Sciences (LIPI), Bogor. The soil was collected randomly from 16
sites in WBiG, and taken from 0-15 cm depth. Isolates of microbes were identified by Bergeys manual method for bacteria; Ellis method for
fungi, and the morphology of isolate method for Actinomycetes. The population of microbes was estimated by plate count method. The
result of isolation, identification and population soil microbes from 16 samples in WBiG showed that 20 isolates of bacteria (Azotobacter
sp., Accinetobacter sp. , Bacillus sp., Citrobacter sp., Flavobacterium sp., Klebsiella sp., Nitrosomonas sp., Pseudomonas sp., Rhizobium
sp., Thiobacillus sp., Azospirillum sp., Azotobacter chrococcum, Bacillus panthothenticus, Chromobacterium violaceum, C.lividum,
Escherrrichia coli, Flavobacterium breve, Klebsiella aerogenes, Spaerotillus natans, and Staphylococcus epidermidis); nine isolates of fungi
(Aspergillus niger, Bisporomyces, Monilia sp., Cephalospharium sp., Verticillum sp., Giocladium sp., Penicillium sp., Nelicocephalum sp.,
and Cuninghamella sp.), and seven isolates of Actinomycetes (Streptomyces, Streptosporangium, Nocardia, Thermomonospora,
Thermoactinomyces, Micromonospora, Mycobacterium). The population of Bacillus (10
8
-10
9
), Rhizobium (10
6
-10
7
), Azospirillum (10
6
-10
7
),
and Thiobacillus (10
4
-10
9
) were founded all of soil samples.
2005 Jurusan Biologi FMIPA UNS Surakarta
Key words: soil microbes, Wamena Biological Garden (WbiG).
INTRODUCTION
Biodiversity of soil microbes has been regarded as
human and vegetation life resource, especially the one
connected with biological and environment resources. This
can be achieved by developing a conservation system of
ex-situ, like the one being pioneered by Indonesian Institute
of Sciences (LIPI) in Kabupaten Jayawijaya called Wamena
Biological Garden (WBiG). This is the first conservation
area of ex-situ mountain biota in the Eastern part of
Indonesia. It is located on Susu mountain and its surround-
ings with the height of l595-1670 m above sea level. The
temperature is 15-26C with a rainfall of 1500-1900 mm. It
has a wet tropical climate with vague difference between
rainy and dry seasons (SW, 2004, personal observation).
WBiG is hilly with steep and gradual slopes having
various typical soil colors which make it possible for the
diversity of microbes, especially in rhizosphere area. WBiG
environment is still virgin and has not been touched by the
cruelty of chemical fertilizers and pesticides, and is an
advantage and gives a positive impact to vegetation and
indigenous microbes. Especially photosphere area, it is rich
in biological activities as microbes feed on the carbon
compounds exuded by root. Plants may exude compounds
that attack certain species to the rhizosphere that protect
the root from diseases (SW, 2004, personal observation).
Soil is a unity of subsistence that includes the varieties
of microbes, because microbes community is one of the
important components of soil, therefore, the microbial
activity and species compositions are generally influenced
by the physical characteristic and soil chemical properties,
climate and vegetation (Jha et al., 1992).
Soil microbes are one of biota communities, which are
very interesting to be studied in order to find out their
existence and uses. So, soil microbes have an important
role to the subsistence on earth, because it has the role on
biological and chemical cycling among the flora, fauna, and
life of microbes itself. Nevertheless, not every soil microbe
is suitable and compatible with the habitat and its host, and
it is well known that they can perform symbiotic and com-
mensalisms. Each type of microbes fills as a unique niche and
plays a different role in nutrients cycling and soil structure.
Microorganism living in the soil can be grouped into
bacteria, fungi, actinomycetes, algae, and protozoa (Rao,
1994). Some groups of soil microbes are useful as biofer-
tilizer and biocontrol. They were Klebsiella, Nitrosomonas,
Thiobacillus, Lactobacillus, Azotobacter, Azospirillum,
Rhizobium, Bacillus, Pseudomonas, and Frankia (one of
actinomycetes group). The other actinomycetes group is
Streptomyces. It is potential as a source of various bioactive
compounds used in pharmaceutical industry, agriculture
and for other purpose. These Streptomyces were found to
have high biodiversity and can be used as source of germ
plasm. The work was also done to find candidate of bio-
pesticide from Streptomyces that can be applied together
with Rhizobium and phosphate solubilizing bacteria as bio-
fertilizer (Lestari et al., 2002). Thus the soil microbes
perform a wide range of function in the ecosystem.
The aim of the research is to know the biodiversity of
soil microbes from rhizosphere at WBiG.
B I O D I V E R S I T A S ISSN: 1412-033X
Volume 6, Nomor 1 Januari 2005
Halaman: 6-11
DOI: 10.13057/biodiv/d060102
WIDAWATI et al. – Soil microbes at Wamena Biological Garden
7
MATERIALS AND METHODS
The soil was collected randomly (sampling square
method/stratification) from 16 sites from rhizosphere area at
WBiG such as Susu mountain, Dapuk hill, Dapuk valley and
near Dapuk river area. Soil sample number 1 to 11 was
collected from Susu mountain area. This area was
dominated by Imperata cylindrica. Whereas number 12 to
16 were collected from Koliken valley, Koliken hill and
surround of Dapuk river. This area was dominated by I.
cylindrica and seno (Castanopsis accuminattisima). The soil
sample was taken from rhizosphere (0-15 cm depth). There
are many different color types, physical element, and soil
chemistry. It founded 11 type soil samples from WBiG
(Table 1. and 2.).
One kg soil sample from 16 sites at WBiG was kept in
black plastic bags (still in fresh condition) and in the Soil
Microbiological Laboratory, Microbiology Division, Research
Center of Biology, Indonesian Institute of Sciences, Bogor
these samples were air dried before the analysis of physic
element and soil chemistry. The identification of microbes
population used fresh soil. The population of microbes was
determined by serial dilution plate count method
(Thompson, 1989; Ravina et al., 1993). Isolation,
identification, and the count of population of microbes used
a selective medium, i.e. Pikovskaya, tauge agar, mannitol
ashby, okon, yema congo red, DPY, PY, Na, LB, TA, etc.
Identification of soil microbes was estimated by morpho-
logy, physiological test, microscopic and chemistry test.
Isolation, identification and population procedure of bacteria
Ten grams fresh soil was suspended into 90 ml distilled
water solution. Mix on wrish action shaker for one hour to
provide mechanical desegregation of bacterial cell.
Subsequent dilutions were prepared by manually shaking
the suspension for 10 seconds to resuspend the soil. Then
transfer 1 ml an aliquot with a sterile pipette to 9 ml sterile
distilled water in a test tube. This suspension was shacked
manually for 10 seconds, and subsequent serial dilutions
were prepared as method as noted above 10
-1
to 10
-7
.
Spread 0.2 ml of soil suspension from each serial dilution
onto isolation selective agar medium (Pikovskaya, okon,
manitol ashby, yema congo red, DPY, and PY). The
number of bacteria colony was estimated after 3-7 days of
incubation at 28
o
C by plate count method. Pick up the
colonies to the same isolation medium, 8 strains per
petridish. Select and transfer the different colonies to
nutrient agar or LB (culture collection medium) or selective
agar medium. The isolates of bacteria were identified by
using morphological characteristic as observation of cell
shape by monstaining (coccus, rod, short
rod/filamentous and spore formation), gram,
stain, observation of living cell (motility, spore
formation, and single, paired or chain) (Krieg and
Holt, 1984).
Isolation, identification, and population procedure
of fungi
Ten grams soil sample was suspended onto
90 ml of distilled water (in erlenmeyer glass),
than mix on writh action shaker for one hour at
120 rpm. The soil extract was diluted from 10
-1
to
10
-7 .
Spread 0.2 ml soil sample suspension from
each serial dilution onto isolation TA medium with
antibiotic. It was inoculated at 28
o
C for 3 days.
Pick up the colonies to the same isolation
medium. Select and transfer the different colonies to be
identified by Charmichael et al. (1980), Domasch and Gans
(1980), and Ellis (1993).
Isolation, identification, and population procedure of
actinomycetes
Soil samples were dried at room temperature for 3 to 5
days. Then they were heated at 90 to 110
o
C for 10 to 60
minutes. The soil samples were spreaded onto isolation
agar medium. They were incubated at 28
o
C for 7 to 14
days. Pick up the colonies to the same agar medium (8
colonies/petridish). The isolates were selected and
transferred colonies to humic acid containing medium and
YS medium. The isolation of medium for actinomycetes was
humic acid-Vitamin agar medium: Humic acid 0.3 g,
Na2HPO4 0.5 g; KCl 1.7 g, MgSO4.7H2O 0.05 g, FeSO4
7H2O 0.01 g, CaCO3 0.02g, B-Vitamins solution 2 ml, 4N-
NaOH 0.6 ml, agar 18 g, pH 7.2. Humic acid-gellan gum
medium: Humic acid 0.3 g, MOPS 1 g, CaCL2 0.44 g, 4 N-
NaOH 0.6 ml, trace element solution 0.5 ml, gellan gum 7
g/liter, pH 7.0. Identification of actinomycetes isolates were
used morphological characteristic i.e. observation of colony
(growth, color of aerial and substrate mycelium, and
diffusible pigment), on ISP No. 2, ISP No. 3, ISP No. 4, and
YS agar media in petridish, microscopic morphology (spore,
sporangium, aerial mycelium and substrate mycelium)
(Miyadoh, 2003).
RESULT AND DISCUSSION
The typical characteristics of soil and vegetation at
WBiG influence soil microbes diversity, such as bacteria,
fungi and actinomycetes population (table 3, 4, and 5). In an
aerobe condition, bacteria dominated the area and carried
out some microbiological activities in the soil because fungi
and actinomycetes could not grow well without oxygen
(Rao, 1994).
Physical and chemical analyses show that, in general,
the soil condition at WBiG is acid with pH range of 4 to 6.
The soil texture is sand clay. According to Rao (1994) the
soil texture depended on the percentage of sand, dust, and
clay. In the case of sand clay or dust clay, its particles came
together to form an aggregate. The stability of an aggregate
depended on both the content of organic matter in each
type of the soil (Table 1.) and the nature condition of
microbes which tied the soil particles to become one. Soil
texture, therefore, is important for microbes and vegetation
to survive in their habitat.
Table 1. Soil physic analysis from 11 sites in Wamena Biological Garden.
Soil
samples
Soil color
Vegetation
Soil Texture (%)
Sand
Clay
Dust
1
Black
Imperata cylindrica
18.03
38.06
43.01
2
Brown
Imperata cylindrica
15.65
35.74
48.61
3
Gray
Imperata cylindrica
10.89
38.82
49.28
4
Red
Imperata cylindrica
11.51
65.75
22.69
5
Brown reddish
Imperata cylindrica
16.36
43.45
40.19
6
Yellow
Imperata cylindrica
17.51
41.42
41.06
7
Lime particle
Imperata cylindrica
35.30
16.06
45.61
8
Black
Pittosporum ramiflorum
5.79
51.37
42.84
9
Brown
Vaccinium varingiaefolium
16.73
28.01
55.26
10
Brown
Castanopsis accuminattisima
20.17
18.56
61.25
11
Dark brown
Grevillea papuana
7.38
52.08
40.54
BIODIVERSITAS Vol. 6, No. 1, Januari 2005, hal. 6-11
8
Table 2. Soil chemistry analysis from 11 sites of Wamena
Biological Garden.
Soil
samples
N
(%)
P
(ppm)
K
(me/100g)
C
(%)
C/N
Ca
(Me/100g)
PH
1
0.25
(m)
2.1
(l)
0.06
(v.l)
2.76
(m)
11.04
(m)
32.90
(v.h)
5.26
(acid)
2
0.23
(m)
2.7
(l)
0.10
(l)
2.47
(m)
10.74
(l)
19.23
(h)
4.25
(acid)
3
0.04
(v.l)
1.6
(v.l)
0.13
(l)
0.36
(v.l)
9.00
(l)
9.73
(m)
4.60
(acid)
4
0.06
(v.l)
0.3
(v.l)
0.07
(v.l)
0.62
(v.l)
10.33
(l)
9.55
(m)
6.05
(acid)
5
0.06
(v.l)
0.2
(v.l)
0.07
(v.l)
0.69
(v.l)
11.50
(m)
8.88
(m)
5.00
(acid)
6
0.05
(v.l)
0.4
(v.l)
0.05
(v.l)
0.51
(l)
10.20
(l)
9.34
(m)
5.25
(acid)
7
0.03
(v.l)
0.1
(v.l)
0.05
(v.l)
0.36
(v.l)
12.00
(m)
9.03
(m)
4.65
(acid)
8
0.21
(m)
4.8
(l)
0.53
(m)
2.54
(m)
12.10
(m)
26.00
(v.h)
5.30
(acid)
9
0.23
(m)
3.3
(l)
0.26
(l)
3.85
(m)
16.74
(h)
8.82
(m)
4.90
(acid)
10
0.22
(m)
1.6
(v.l)
0.15
(l)
3.12
(h)
14.48
(m)
9.34
(m)
4.35
(acid)
11
0.30
(m)
3.9
(l)
0.36
(l)
3.05
(h)
10.17
(l)
19.23
(h)
4.80
(acid)
Annotation: v.l = very low; l = low; m = moderate; h = high; v.h =
very high
The acidity level in soil sample No. 4 with I. cylindrica in
it approached normal pH (6.05) followed by element
contents of N, P, K, C, C/N ratio with a low to moderate Ca
content, and also did the other soil samples. This shows
that most WBiG area is not fertile. This condition occurs
because the agriculture pattern of the people around WBiG
is still very simple and inherently dependent on natural soil
fertility, because rotation system has been being practiced
continuously for a long time, it decreases the soil fertility.
Another possibility is that the people of Wamena never use
chemical fertilizers.
It turned out that the physical and chemical conditions of
the soil did not prevent the existence of microbes in the
rhizosphere (Table 3, 4, 5). Those tables illustrate the
results of microbes identification which go as follows:
Twenty isolates of bacteria (genus and species), nine
isolates of fungi (genus and species) and seven isolates of
actinomycetes (genus). All these isolates were gotten from
soil samples taken from the depth of 0-15 cm under
rhizosphere plants. Thus, soil acidity, soil fertility, soil
texture, vegetation types and perhaps the elevation of area
and soil colors (Figure 1.) can influence the variety and
population of microbes in a rhizosphere. Widawati and
Suliasih (2001) noted, the number of microbes at Halimun
mountain was influenced by the different vegetation type,
soil pH, and the elevation of area. The composition of
population and soil microbes activity were influenced by the
different climate and vegetation (Jha et al., 1992). On the
other hand the activity of microorganisms is constantly
changing with temperature, moisture, pH, food supply and
other environmental conditions. So, different species prefer
different condition. So, microbes are generally assumed
that of the major microbial group’s soil, fungi are tolerant of
acidity, whereas most bacteria and actinomycetes are
relative in tolerant (Gunarto, 2000).
The microbes population in the out area of rhizosphere
was not as numerous as that in the rhizosphere. This can
be seen in soil sample No. 7 (Table3) which contained
limestone. There might have been no association
connection between microbes and local vegetation that the
existence of microbes in the soil is not good. When, an
association occurs between vegetation and microbes, plant
root exudates macro and micro element to release it into
the soil rhizosphere to create a new environment (niche) for
the growth of microorganism (Setiadi, 1989). Looking at the
number of population in the sample taking area Nos. 1, 4, 6,
11, 12, and 15 it was supposed that association connection
between vegetation and microbes had taken place.
Therefore, each type of microbe filled a special niche and
played a different role in the nutrient cycle.
Microbes which were potential as bio-fertilizers were
often found in rhizosphere. This is seen from the
identification results. Several microbes like Azospirillum,
Azotobacter, Pseudomonas, Aspergillus, and Streptomyces
are potential to become bio-fertilizers or bio-controls. It is
possible, because rhizosphere is rich with biological activity
as microbes feed on the carbon compounds exuded by
root, while organic and inorganic materials released by the
plants into the areas (in the form of exudates), will be useful
for life continuity of soil microbes (Setiadi, 1989)
Bacteria
Bacteria are the most dominant microorganisms in the
soil. They may, perhaps, cover half of the biomass in the
soil. Like Table 3., all samples, which were analyzed,
contained bacteria of different population number. In acid
soil type with low to moderate nutrient content, bacteria
population spread unevenly. The result of identification of
11 soil types in 16 rhizosphere locations produced 20 genus
(including 10 species). Azospirillum sp., Bacillus sp.,
Pseudomonas sp., Rhizobium sp., Thiobacillus sp., and
Spaerotillus natans dominated the area. These bacteria are
generally found in the soil regardless of the soil condition
(Rao, 1994). In the identification results of soil sample
number four and fifteen, a bacterium rarely found in the soil
was identified, i.e. Escherichia coli. Rao proposed (1994)
that E. coli was rarely found in the soil, except as a
contaminant or a waste. This happens in the land of
Wamena owing to the fact that natives live a very simple
life. It is probable that they empty the bowels anywhere.
Bacteria can be found in any type of soil but their
population is varied because of the influence of soil texture
and organic substrate in the soil. Bacteria’s ability to survive
in favorable ecosystem is due to their character to form
spores which have thick strong sheathes to make it easier
for them to survive in a savage environment. Bacteria can
also stand extreme climate condition although temperature,
humidity, pH, agriculture practice, fertilizers, pesticide, and
the addition of organic matter can influence their population
(Rao, 1994).
Fungi
The number of fungi in the soil is fewer than those of
bacteria. All fungi have mycelium thread, which are
organized from individual hypha. So, a fungi colony can
dominate all soil types (RAO, 1994).
Fungi identification results of 11 soil types from 16 sites
at WBiG produced nine genus, including one species
(Aspergillus niger) which dominated several places at
WBiG. This species is a fungi colony which can be found in
many soil types because it has saprophytic character
whose spores can be so easily distributed by air that genus
can be present everywhere (in the fields, in the prairie, in
the forest soil and in the degraded land, such as an ex-gold
mine).
WIDAWATI et al. – Soil microbes at Wamena Biological Garden
9
Species domination is also determined
by agriculture activities including crop
plantation (practiced in Wamena) and the
use of chemical fertilizers or pesticides
(not practiced in Wamena). So, it can be
said that fungi is one of the most
important microbes in the soil ecosystem
dynamics, because they function in the
decomposition, mineralization and
organize the migration of soil elements to
plant root (Christensen, 1984 cit Suharna,
1999).
The results of fungi population count
have the same total average (no obvious
difference) (Table 4.). Thus, although a
fungi colony is microbes which is more
resistant to soil acidity, their live hood still
depends on the availability of organic
materials (Soepardi, 1978) and is much
influenced by climate, especially soil
moisture content (Sutejo et al., 1991).
Figure 2. One of bacteria type (holozone of
phosphate solubilizing bacteria).
Figure 3. One of fungi type (holozone of
phosphate solubilizing fungi).
Figure 4. The one of actinomycetes type
Table 3. Identification and Population of soil bacteria from 16 sites at Wamena Biological Garden.
Microbes identified from soil
The number of soil samples
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
The number of bacteria (cell/gram soil)
Azospirillum sp.
2+
2+
2+
2+
2+
2+
2+
2+
2+
2+
2+
2+
2+
2+
2+
2+
Azotobacter chrococcum
2+
2+
1+
1+
1+
1+
A. paspalii
2+
2+
3+
2+
1+
1+
3+
1+
Acinetobacter sp.
1+
Bacillus sp.
3+
3+
2+
3+
3+
3+
3+
3+
3+
2+
3+
3+
3+
3+
3+
3+
B.panthothenticus
3+
2+
3+
Citrobacter sp.
3+
2+
2+
3+
1+
Chromobacterium violaceum
3+
2+
1+
2+
1+
C.lividum
2+
1+
3+
Escherichia coli
1+
1+
Flavobacterium sp.
1+
1+
1+
F. breve
2+
Klebsiella sp.
1+
3+
2+
1+
K.aerogenes
1+
2+
Nitrosomonas sp.
3+
1+
1+
3+
1+
3+
3+
1+
Pseudomonas sp.
2+
3+
Rhizospbium sp.
2+
2+
2+
2+
2+
2+
2+
2+
2+
2+
2+
2+
2+
2+
2+
2+
Spaerotillus natans
2+
3+
2+
2+
2+
1+
3+
+
3+
3+
1+
3+
1+
Staphylococcus epidermidis
2+
1+
3+
`1+
2+
3+
1+
3+
1+
1+
1+
1+
Thiobacillus sp.
2+
1+
1+
3+
1+
1+
1+
1+
1+
2+
2+
1+
2+
1+
1+
1+
∑ all bacteria type
11
9
7
11
8
12
6
9
7
8
11
10
6
8
12
7
Annotation: 1+ = low (10
4
-10
5
), 2+ = moderate (10
6
), 3+ = high (10
7
-10
8
). The vegetation of soil sample No.1 to No.11, same as Table 1.
The vegetation of soil sample No.12 to No 16: Imperata cylindrica, Imperata cylindrica, Ipomoea batatas, Castanopsis accuminattisima and
Castanopsis accuminattisima.
Figure 1. Soil color from 11 sites at Wamena Biological Garden.
BIODIVERSITAS Vol. 6, No. 1, Januari 2005, hal. 6-11
10
Table 4. Identification and population of fungi from 16 sites at
Wamena Biological Garden.
Soil
samples
Vegetation
Species
Pop.
1
Imperata cylindrica
Aspergillus niger
+
2
Imperata cylindrica
Bisporomyces sp..
+
3
Imperata cylindrica
Monilia sp.
+
4
Imperata cylindrica
Aspergillus niger
+
5
Imperata cylindrica
Aspergillus niger
+
6
Imperata cylindrica
Cephalospharium sp.
+
7
Imperata cylindrica
Aspergillus niger
+
8
Pittosporum ramiflorum
Aspergillus niger
+
9
Vaccinium varingiaefolium
Aspergillus niger
+
10
Castanopsis accuminattisima
Verticillum sp.
+
11
Grevillea papuana
Gliocladium sp.
+
12
Imperata cylindrica
Penicillium sp.
+
13
Imperata cylindrica
Penicillium type A
+
14
Ipomoea batatas
Penicillium type B
+
15
Castanopsis accuminattisima.
Nelicocephalum sp.
+
16
Castanopsis accuminattisima.
Cuninghamelle sp.
+
Table 5. Identification and population of actinomycetes from 16
sites at Wamena Biological Garden.
Soil
samples
Vegetation
Genus
Pop.
1
Imperata cylindrica
Streptomyces
+
2
Imperata cylindrica
Streptomyces
+
3
Imperata cylindrica
Streptosporangium
+
4
Imperata cylindrica
Streptomyces
+
5
Imperata cylindrica
Nocardia
+
6
Imperata cylindrica
Nocardia
+
7
Imperata cylindrica
Streptomyces
+
8
Pittosporum ramiflorum
Micromonospora
+
9
Vaccinium varingiaefolium
Streptomyces
+
10
Castanopsis accuminattisima
Streptomyces
+
11
Grevillea papuana
Micromonospora
+
12
Imperata cylindrica
Thermoactinomyces
+
13
Imperata cylindrica
Streptomyces
+
14
Ipomoea batatas
Streptomyces
+
15
Castanopsis accuminattisima.
Thermomonospora
+
16
Castanopsis accuminattisima.
Mycobacterium
+
In the acid soil area, dominated by Myristica cylindrica
plants, eight fungi isolates were found and were dominated
by A. niger. That species and other genus like
Cuninghamella and Penicillium have a wide distribution,
especially in the tropic and subtropics areas (Domsch and
Gams, 1980). Then Sutedja (1991) stated that even though
fungi were resistant to soil acidity, they were not resistant to
drought and poor nutrition in the soil. It was the same with
WBiG soil condition. The soil is so acid with low nutrients
content that the number of fungi found was fewer than
those of other microbes like bacteria Rao (1994) said that
all environment factors which influenced bacteria and
actinomycetes migration also influenced the migration of
fungi in the soil.
Actinomycetes
Actinomycetes (order Actinomycetales) are a group of
prokaryotic organisms belonging to gram-positive bacteria.
Many of them show a branched filamentous growth, and
generally form spores and some actinomycetes even form
sporangia and zoospores. It mainly inhibits the soil and
plays an important ecological role in recycling substances in
the natural world (Miyadoh, 2003). Identification produced
6 genus from 16 soil samples, i.e. Mycobacterium,
Nocardia, Micromonospora, Thermoactinomyces
Streptosporangium, Actinomycetes, Thermonospora, and
Streptomyces (Table 5. and 6.). Considering actinomycetes
in the soil was quite plentiful, it was surprising that it was
lack of the number of genus varieties. It is possible that the
WBiG’s soil ecosystem is not good enough for
actinomycetes resulting from acid pH and low soil nutrient.
Most actinomycetes are not tolerant to soil acidity.
The population of actinomycetes will decrease at pH 5.0
(the suitable range is 6.5 to 8.0). Another factor is the
method of taking the sample. It turned that the soil sample
for identification was different from the soil sample for
bacteria and fungi identification (0-15 cm depth). According
to RAO (1994), the deeper the soil, the higher was the
percentage of actinomycetes in the total microbes
population. The increase of the discomposed organic matter
would also increase the number of actinomycetes.
The identified actinomycetes were common genus, for
example Streptomyces (almost 70%), Nocardia and
Micromonospora (Table 5a), while Streptomyces genus was
often found in the heap of garbage with the temperatures of
55C to 65C. Streptomyces species are very common in
soil and responsible for the decomposition and degradation
of natural and synthetic organic. Anonymous (2000) cit
Sembiring (2003), note the genus of Streptomyces
accommodates an unusually high degree of natural
diversity with more than 500 validly described species.
Nevertheless, a steady flow of new Streptomyces species
are being described to accommodate either organisms
isolated from diverse habitat.
Table 6. Representative characteristics of actinomycetes.
Genus
Isolates No.
Morphology
Vegetative cell
Aerial mycelium
Sporangium
Spore
Motility
Family Corybacteriaceae
Mycobacterium
16
rod
-
-
-
-
Nocardia
5 and 6
mycelia, fr
+
-
long
-
Family Micromonosporaceae
Micromonospora
8 and 11
mycelia
-
-
-
Family Streptosporangiaceae
Streptosporangium
3
mycelia
+
+
multi
-
Family Thermomonosporaceae
Thermomonospora
15
mycelia
+
-
1
-
Family Streptomycetaceae
Streptomyces
1,2,4, 7,9,10, 13, 14
mycelia
+
-
long
-
Others
Thermoactinomyces
12
mycelia
+
-
1
-
