1. STUDIES ON MICROBIAL INOCULATION IN THE PREPARATION OF PHOSPHO-COMPOST USING
FOREST LEAF LITTER
K. S. Usha1, A. N. Balakrishna1, D. N. Padma1, M. Raghavendrakumar1, N.G. Kumar2, P. Nirmala2
and B.V. Chinnappa Reddy3
1. Department of Agricultural Microbiology; 2. Department of Agricultural Entomology; 3. Department of Agricultural Economics
University of Agricultural Sciences, GKVK Campus,
Bangalore-560065, Karnataka, India
INTRODUCTION 42.2
45 40 3.5 3.19
37.4 38.4
40
The value of organic wastes as soil conditioner has been the subject of 33 3
35 2.45
Organic-C (%)
considerable debate. The simplest and most common method of 39.9 2.5
30 26.3 30 2.11 2.42
Total N (%)
estimating the value of organic wastes is to convert the wastes to useful 25 32.2 60 2 1.66 1.59
30
compost as a substitute for commercial fertilizers. Further, microbial 20 1.5 1.56 60
90
inoculation with efficient decomposing microbial cultures hastens the 15 1
0.89 90
Mean Mean
processes of decomposition and addition of rock phosphate enriches the 10 0.5
compost with P. 5
1 0
0
Control Treated
Control Treated
MATERIAL AND METHODS Treatments
Treatments
2
Treatment details: 1. Control 2. Inoculated with microbial consortium 1.79
60
1.8 1.64
Microbial consortium: Trichurus spiralis, Trichoderma harzianum and 1.6
49.3
1.45 50
Pleurotus sp. 1.4
NH4-N (m g/g)
Replications: 13 samples were drawn from each of the Vat and 30 40 30
C:N ratio
1.2
1.63 60
analyzed separately. Design: CRD 60
1 0.84 0.87
1 30 25.5 25.4
90 90
Leaf litter: The leaf litter consisted of Roncilate sp. (125 kg) 0.8 0.63 17.9
Mean 20 13.2
Strobilanthes sp. (100 kg), Lepisanthes descipens (25 kg) and Euginea 0.6 30.9 Mean
0.78
8.3
jambolana (25 kg). 0.4 10
0.2
15.6
Cow Dung: Cow dung was added at 10% of the weight of the leaf litter 0 1
0
used (25 kg). Control Treated
Control Treated
Rock phosphate: Rock phosphate was added at 2% P2O5 of the weight Treatments
of leaf litter. Treatments
Vats: The vats of size 6’ x 4’ x 3’ were made from locally available palm
stems.
35 32.22
A v a i l a b l e P 2 O 5 (m g / g s o il )
30 2
25.05 1.6
25 1.4
NO3-N (mg/g)
21.22 30 1.5 30
26.17 1.16
20 60 60
90 1 0.74 0.74 1.43
15 12.57 90
8.8 9.69 Mean
10 0.5 0.35 Mean
0.61
5 10.36
0
0 1
Control Treated
Control Treated
Treatments
Treatments
40
35 35.66
3.5 3.09
Abundance (#/400g sam ple)
30
3
2.68 28.16
Collembola
T o t a l P ( g /K g s o il)
2.24 25
2.5 30 Cryptostigmatids
20 18.33 Other Mites
2 60
15.16 Other invertebrates
90 15
1.5 Total fauna
1.02 9.58
Mean 10
1 0.68
0.651 0.7 6.41
4.25 5.16
0.36 5 2.33 2.58
0.5
1
0
0
Control Treated
Control Treated Treatments
Treatments
CONCLUSION
Inoculation of microbial cultures to forest leaf litter has significantly reduced the time
required for decomposition of forest leaf litter.
RESULTS
A good compost of C/N ratio 13.2 could be obtained 30 days earlier compared to without
inoculation.
Inoculation of leaf litter with MIC has significantly reduced the organic-C
(32.2%) as compared to control (39.9%) over 90 days of decomposition. The compost thus prepared was also high in nitrate-N, total-N and available-P. Such
The total-N significantly increased by 90 days (2.42%) in the treatment improvement in the quality of compost is due to inoculation with microorganisms.
with MIC as compared to the control (1.56%).
Further, enrichment with rock phosphate and microbial inoculation enhanced the available-P
The C:N ratio was significantly reduced at all the intervals over the content in compost.
period of decomposition both in control as well as in treatment with
microbial consortium. However, the C: N ratio in the treatment with This is due to solubilization of insoluble-P present in the rock phosphate during the process
microbial consortium was 13.2 as compared to the control (25.5) at 60 days of decomposition and this can replace the costlier super phosphate in sustainable agriculture.
of decomposition suggesting that a good compost could be obtained 30
days earlier.
ACKNOWLEDGEMENT
Significantly higher soil faunal population was observed in leaf litter
with MIC+MRP treatment compared to control. Further, the populations of The authors are grateful to TSBF-CIAT/GEF/UNEP for the financial support to carryout
Collembola, cryptostigamtids, other Acari and other invertebrates were the investigation.
higher in this treatment than control.
Significantly higher rate of ammonification and nitrification due to
REFERENCES
microbial consortium was recorded at all periods of decomposition. Leal, N., Canizalez, C.M-de. and de-Canizalez,C.M., 1998. Composting of organic residues
Significantly higher available-P2O5 and total- P2O5 contents in compost due mixed with rock phosphate. Agronomia Tropical Maracay, 48(3): 335-357.
to inoculation of MIC were recorded as compared to the control over a Parr, J.F. and Hornick, S.B., 1992. Utilization of Municipal wastes. In: Soil Microbial Ecology.
period of 90 days decomposition. (Ed. Blaine Metting, Jr). pp. 545-560.