Effect of irrigation regions and mulcher in microbial population of said on Aonla (Emblica officinalis Greartn) cv. NA-10 under sodie soil.
Dr. Mohd. Suhail, drsuhial.lmp@gmail.com, Mob. 9450384746, KVK Lakhimpur
Key worlds : Aonla drip, fungus, bacteria earthworms
ABSTRACT
Total number of earthworm increased significantly with increasing level of irrigation (I1) and it was maximum in mulching by paddy straw. Application of water at I3 (IW/CPE=0.6) irrigation regime produced significantly maximum number of fungal colonies and bacterial population in I1 (IW/CPE=1.0) irrigation regime. The total number of fungal and bacterial population was maximum in paddy straw mulching. Interactive effect of irrigation regimes and mulches proved beneficial in improving the microbial population of the soil. The maximum number of bacterial and fungal colony were observed in I3M2 and I2M2 treatment combination, respectively.
INTRODUCTION
Aonla or Indian Goosberry (Emblica officinalis) thrives well in varied climate and soil conditions in the country. In recent years its cultivation is inereasing rapidly particularly in salt affected soil (sodic, saline) and also in ravines area. Drip irrigation coupled with mulching can play an important role in conserving oil moisture, regulating soil temperature, reducing soil erosion, improving soil structure and control the weed population. Continuous use of organic mulches also helps in physio-chemical and biological properties of the soil. The present investigation was design to find out the effect of drip irrigation and mulching on fungal bacterial and earthworm population in the soil.
MATERIAL AND METHOD
A two years field experiment was conducted during 1996-97 and 1997-98 at Main Experimental Station of N.D.U.A. & T. Kumarganj, Faizabad. The site is lies between a latitude of 24.470 and 26.560 and longitude of 81.120 and 83.890 at an elevation of 113.0 meter of mean sea level. There were four irrigation regimes and three mulching treatments.
Table 1: Detail of treatment combinations and their notation
S.N. Details of treatment combination Notation
1 IW / CPE = 10 + Black polythene I1M1
2 IW/ CPE = 10 + Paddy straw I1M2
3 IW / CPE = 10 + Control I1M3
4 IW / CPE = 0.8 + Black polythene I2M1
5 IW/ CPE = 0.8 + Paddy straw I2M2
6 IW / CPE = 0.8 + Control I2M3
7 IW / CPE = 0.6 + Black polythene I3M1
8 IW/ CPE = 0.6 + Paddy straw I3M2
9 IW / CPE = 0.6 + Control I3M3
10 IW / CPE = 0.4 + Black polythene I4M1
11 IW/ CPE = 0.4 + Paddy straw I4M2
12 IW / CPE = 0.4 + Control I4M3
Where,
IW is depth of irrigation water (cm)
CPE is cumulative pan evaporation (mm) recorded class ‘A’ pan evapometer
Details of layout are given below
(i) Design - Factorial R.B.D. (ii) Number of replication - Three
(iii) Irrigation frequency - Third day interval (iv) Experimental unit - Two
(v) Experimental material - Aonla cv. N.A. 10 (vi) Size of basin - 3.0 x 3.0 m2
Application of water
Water is usually applied by drip method on the bases of cumulative pan evaporation which is an indirect estimation method crop water status. The evaporation was daily recorded form the Department of Meteorology with the help of class ‘A’ pan evapometer. The amount of water required was computed at the ratio of IW over CPE at third day interval for irrigation treatment as per the following formula:
Quantity of water (liter)
= (Size of baisn 〖(m〗^2) ×depth of irrigation (cm)×Pan evaporation (mm))/100
Mulching
Black polythene sheet of 400 gauge of 4.0 x 4.0 m2 size was unrolled on the surface of the basin with their corner and side stitched with stacking pins and their other side tagged in soil to avoid rolling and splitting on account of strong winds. Paddy straw @ 20 Kg/plant (approximately 10 cm thickness) was spread over the tree basin and there were no mulches in control treatment. The mulches were placed after fertilization, irrigation and weeding the experimental plots to ensure the uniform moisture content.
Cultural Operations (Manuring and fertilization)
Plant were supplied with uniform dose of farm yard @ 50 kg per plant and chemical fertilizer @ 800 g N, 600 g P2O5 ad 800 g K2O per plant into two split doses, one half dose at the time of mulching (Feb.) and second half dose in the last month of August.
Microbial population
Soil sampling : Soil samples were collected from the basin of aonla plants at 0 – 20 cm depth with the help of screw augur at the termination of experiment. Soil samples of all replications were mixed thoroughly to make the composite sample for analysis.
Dilutaion procedure: The composite soil samples (10 g) each were suspended in 95 ml of distilled water to obtain a dilution of 110 shaking the suspension vigorously for 5 minutes and allowing to settle down the coarse particles. Adequots the 1 ml solution from the suspensed sample with the help of sterile pipette and discharge in a culture tube containing 99 ml. distilled water to obtain 1 : 100 dilution, similarly 1 : 1000, 1 : 10000 and 1 : 100000 dilutions were also prepared. All the procedure done in under aseptic condition of laminar flow fitted with UV lamp.
Isolation of fungi
Culture media: Mortine agar media was used for isolation of soil fungi during the investigation is given in Table 2
Table 2: The composition of media
S. No. Ingradient Quantity S. No. Ingradient Quantity
1. Streptomycine sulphate 1.0 g 5. Agar 20.0 g
2. Peptone 5.0 g 6. Rose Bengal 0.033 g
3. Potassium dihydrogen Phosphate (KH2PO4) 1.0 g 7. Distilled water 1000 ml
4. Magesium suplhate (MgSO4 7H2O) 0.5 g 8. Glucose 2.0 g
Procedure: One milliliter of finally diluted soil sample was poured into 20 petridish in which 15 ml of distilled melted Mortine agar medium. After inoculation, the Petri dishes were incubated in BOD incubator at 25 + 20C for a period of one week to allow fungal growth. Fungal growth (colonies) were counted with the help of colony counter from the first appearance of the colony for a week of incubation.
Isolation of bacteria
Culture media: The composition of nutrient agar media was used for isolation of soil bacteria is given in Table 3.
Tables 3. The compostition of media.
S.No. Ingradient Quantity S.No. Ingradient Quantity
1. Glucose 1.0 g 3. Agar 20.0 g
2. Potassium orthophosphate 0.5 g 4. CaCO3 0.5 g
Procedure: The number of bacteria were isolated by dilution plate technique. Each Petri dish was poured with 15 ml of melted agar. Quickly diluted samples were inoculated and Petri plates were rotated clock and anticlock wise and left for solidification. Inoculated Petri plates were kept in the inverted position for a period of one week at 25+30C in BOD incubator. The bacterial colonies were counted carefully after incubation at both the surfaces. The number of bacteria per g of oven dry soil was calculated by following formula.
Bacteria per g dry soil = (average count ×dilution)/(dry weight of one gram moist soil)
Number of earthworm (per 0.15m3)
The number of earthworms were counted on soil surface and upto the depth of 15 cm.
Table 4: Effect of drip irrigation regimes and mulching on earth worms fungal and bacterial population of the soil
4.1 Earthworms population (per 0.15 m3)
Mulching Irrigation (IW/CPE
I1 I2 I3 I4 Mean
M1 20.21 17.13 16.88 15.00 17.31
M2 25.59 22.92 21.34 20.42 22.57
M3 21.50 21.00 19.04 18.08 19.91
Mean 22.43 20.35 19.09 17.83
CD (at 5%) I = 1.652 M = 1.429 I x M = NA
4.2 Fungal population (000 g-1 of soil)
Mulching Irrigation (IW/CPE
I1 I2 I3 I4 Mean
M1 55.75 62.21 163.33 209.84 122.78
M2 72.84 78.79 259.25 136.88 136.94
M3 82.59 99.17 181.22 39.34 100.58
Mean 70.39 80.06 210.27 128.67
CD (at 5%) I = 11.352 M = 9.832 I x M = 19.662
4.3 Bacterial population (m g-1 of soil)
Mulching Irrigation (IW/CPE
I1 I2 I3 I4 Mean
M1 8.75 6.34 4.52 3.65 5.83
M2 8.95 9.63 9.52 6.78 8.72
M3 6.69 2.50 2.01 1.53 3.18
Mean 8.13 6.16 5.35 3.99
CD (at 5%) I = 0.538 M = 0.470 I x M = 0.937
RESULT AND DISCUSSION
Earthworm
The average date illustrated in table (4.1) that earthworm population tends to increase (22.43) significantly in regime (I1) and there was a decline dramatically in response to deficit of water at I4 (IW/CPE = 0.4). It might be due to two major variables i.e. temperature and moisture affect the earthworm population. However, higher amount of water significantly increases the earthworm population.
Interaction of these two factors was found non significant on earthworm population. However, the maximum number of earthworm (25.59) was recorded in I1 (IW/CPE = 1.0) irrigation regime with paddy straw mulching (M2) it was followed by I2M2, I1M3, I3M2, and so forth.
The benefit of organic mulch (paddy straw) demonstrated maximum number of earthworm (22.57) followed by control and black polythene mulching. Organic mulches reduced tillage and maintain moisture which affects earthworm population (Edwards and Lofty 1982b; Werner and Dindal, 1989, Berry and Karlen, 1993)
Fungal population
It is revealed from Table (4.2) and Fig (1) that the fungal population in soil was significantly affected by irrigation regimes, mulching and their interaction.
The maximum number of fungal population (210.27) was counted in I3 (IW/CPE = 0.6) irrigation regime, it was followed by I4 (128.68), I2 (80.06) and I1 (70.39), however I1 and I2 was found statistically akin.
It is clear from the observation that paddy straw mulching produced significant maximum number of fungal population (136.94), strived by black polythene mulching (M1) and without mulching (M3) treatment.
The interaction effect of different irrigation regimes and mulching methods showed that the fungal population in the soil varied from 39.34 to 259.25 (Table 4.2). Among the different treatments combinations I3M2 produced significantly maximum number (259.25) of fungi per g of soil and it was accompanied by I4M1, I3M3, I3M1, and I4M1 and so on.
The highest fungal population in I3 irrigation indicates that the high moisture reduced the fungal population in the soil. Same findings are reported by Dhingra and Changes (1981).
Bacterial population
It is observed from Table (4.3) & Feg.No. 2 that bacterial population in soil was significantly influenced by irrigation regimes, mulching and their interaction.
The bacterial population was significantly maximum (8.13) in I1 irrigation regime and it was followed by I2, I3 and I4.
Similarly mulching with paddy straw showed significant maximum number of bacterial (8.72) which was followed by black polythene (M1 = 5.83) and control (M3 = 3.18).
The interaction effect of different irrigation regimes and mulching methods indicated that bacterial population per g of soil varied from 1.53 to 9.63 as illustrated in Table (4.2). Maximum number of bacteria was recorded in I2M2 and the same was followed by I3M2, I1M2, I1M1, I4M2 and so on. However, minimum number of bacteria was recorded in I4M3 treatment combination.
It has been attributed that the bacterial activities were maximum at higher level of moisture (I1) and decreased sharply as soil moisture decreased. It might be due to bacteria require high amount of moisture for their development in the soil. The results are also earlier report by Batthacharya and samedder (1976), Griffin (1983), Nicosia and Barbagallo (1987). It is well known that fungi and bacteria play an important role in soil fertility through their activities on organic matter decomposition and nutrient cycl. The present results also verified by the work of Baath and Soderstorm (1982). Marumata et al. (1991). Camprubi et al. (1995).
LITERATURE CITED
Baath, E.; soderstrom, B. (1982). Seasonal and spatial variation in fungal biomass in a forest soil. Soil Bio. Biochem. 14 : 353 – 358.
Berry, E.C.; Kalen, D.L. (1993). Composition of altenative forming system II. Earthworms population density and species diversity. Ame. J. Alt.ern. Agric., 8 : 21-26
Bhattacharya, M.; Smadhar, K.R. (1976). Epidemological studies on jute disease. Survival of Macrophomina Phascoli (Maubl). in soil. Plant and Soil, 44 : 27-36
Camprubi, C.; Calvet, C.; Estaum, V. (1995). Growth enhancement of citrus reshni after inoculation with Glomus intorardices and Trichoderma aurcovrinde and enzyme activity in potting mixes. Pland and Soil, 173 (2) : 233 – 238.
Dhingra, O.D.; Changas, D. (1981). Effect of soil temperature; moisture, and nitrogen and competilive saprohytic ability of Macrophomia phaseolino. Transaction of British Myeological Society, 77 (1) : 15 – 20.
Edwanrds, C.A.; Lafty, J.K. (1982 b). Nitrogen fertilizers and earthworms population in agriculture soil. Soil Bio. Biochem., 14 : 515 – 521.
Griffin, D.C. (1963). Soil physical factors and ecology of fungi III activity of fungi in relatively dry soil. Transaction of the British Mycological Society, 46 : 373 – 377.
Marumata, T.; Aaki, M.; Suzuk, Y.; Kusaka, T.; Kheng, J.W.C.; Higashi, T. (1991). Effect of rhizosphere conditions on the growth of strawberry I. Effect of nitrogen level, soil temperature and mulch. Bulletin of faculty of Agriculture, Yamaguchi University, No. 39 : 23 – 35.
Nicois, O.L.D.; Barbagallo, S.C. (1987). Irrigation experiment with practically treated waste water. Rivisa di ingegneria Agriaria, 18 (2) : 98 – 103
Werner, M.R.; Dinda, D.L. (1989). Earthworm community dynamics in convertional and low input agro ecosystem. Rev. Ecol. Biol. Soil, 26 : 427 – 437
Dr. Mohd. Suhail, drsuhial.lmp@gmail.com, Mob. 9450384746, KVK Lakhimpur
Key worlds : Aonla drip, fungus, bacteria earthworms
ABSTRACT
Total number of earthworm increased significantly with increasing level of irrigation (I1) and it was maximum in mulching by paddy straw. Application of water at I3 (IW/CPE=0.6) irrigation regime produced significantly maximum number of fungal colonies and bacterial population in I1 (IW/CPE=1.0) irrigation regime. The total number of fungal and bacterial population was maximum in paddy straw mulching. Interactive effect of irrigation regimes and mulches proved beneficial in improving the microbial population of the soil. The maximum number of bacterial and fungal colony were observed in I3M2 and I2M2 treatment combination, respectively.
INTRODUCTION
Aonla or Indian Goosberry (Emblica officinalis) thrives well in varied climate and soil conditions in the country. In recent years its cultivation is inereasing rapidly particularly in salt affected soil (sodic, saline) and also in ravines area. Drip irrigation coupled with mulching can play an important role in conserving oil moisture, regulating soil temperature, reducing soil erosion, improving soil structure and control the weed population. Continuous use of organic mulches also helps in physio-chemical and biological properties of the soil. The present investigation was design to find out the effect of drip irrigation and mulching on fungal bacterial and earthworm population in the soil.
MATERIAL AND METHOD
A two years field experiment was conducted during 1996-97 and 1997-98 at Main Experimental Station of N.D.U.A. & T. Kumarganj, Faizabad. The site is lies between a latitude of 24.470 and 26.560 and longitude of 81.120 and 83.890 at an elevation of 113.0 meter of mean sea level. There were four irrigation regimes and three mulching treatments.
Table 1: Detail of treatment combinations and their notation
S.N. Details of treatment combination Notation
1 IW / CPE = 10 + Black polythene I1M1
2 IW/ CPE = 10 + Paddy straw I1M2
3 IW / CPE = 10 + Control I1M3
4 IW / CPE = 0.8 + Black polythene I2M1
5 IW/ CPE = 0.8 + Paddy straw I2M2
6 IW / CPE = 0.8 + Control I2M3
7 IW / CPE = 0.6 + Black polythene I3M1
8 IW/ CPE = 0.6 + Paddy straw I3M2
9 IW / CPE = 0.6 + Control I3M3
10 IW / CPE = 0.4 + Black polythene I4M1
11 IW/ CPE = 0.4 + Paddy straw I4M2
12 IW / CPE = 0.4 + Control I4M3
Where,
IW is depth of irrigation water (cm)
CPE is cumulative pan evaporation (mm) recorded class ‘A’ pan evapometer
Details of layout are given below
(i) Design - Factorial R.B.D. (ii) Number of replication - Three
(iii) Irrigation frequency - Third day interval (iv) Experimental unit - Two
(v) Experimental material - Aonla cv. N.A. 10 (vi) Size of basin - 3.0 x 3.0 m2
Application of water
Water is usually applied by drip method on the bases of cumulative pan evaporation which is an indirect estimation method crop water status. The evaporation was daily recorded form the Department of Meteorology with the help of class ‘A’ pan evapometer. The amount of water required was computed at the ratio of IW over CPE at third day interval for irrigation treatment as per the following formula:
Quantity of water (liter)
= (Size of baisn 〖(m〗^2) ×depth of irrigation (cm)×Pan evaporation (mm))/100
Mulching
Black polythene sheet of 400 gauge of 4.0 x 4.0 m2 size was unrolled on the surface of the basin with their corner and side stitched with stacking pins and their other side tagged in soil to avoid rolling and splitting on account of strong winds. Paddy straw @ 20 Kg/plant (approximately 10 cm thickness) was spread over the tree basin and there were no mulches in control treatment. The mulches were placed after fertilization, irrigation and weeding the experimental plots to ensure the uniform moisture content.
Cultural Operations (Manuring and fertilization)
Plant were supplied with uniform dose of farm yard @ 50 kg per plant and chemical fertilizer @ 800 g N, 600 g P2O5 ad 800 g K2O per plant into two split doses, one half dose at the time of mulching (Feb.) and second half dose in the last month of August.
Microbial population
Soil sampling : Soil samples were collected from the basin of aonla plants at 0 – 20 cm depth with the help of screw augur at the termination of experiment. Soil samples of all replications were mixed thoroughly to make the composite sample for analysis.
Dilutaion procedure: The composite soil samples (10 g) each were suspended in 95 ml of distilled water to obtain a dilution of 110 shaking the suspension vigorously for 5 minutes and allowing to settle down the coarse particles. Adequots the 1 ml solution from the suspensed sample with the help of sterile pipette and discharge in a culture tube containing 99 ml. distilled water to obtain 1 : 100 dilution, similarly 1 : 1000, 1 : 10000 and 1 : 100000 dilutions were also prepared. All the procedure done in under aseptic condition of laminar flow fitted with UV lamp.
Isolation of fungi
Culture media: Mortine agar media was used for isolation of soil fungi during the investigation is given in Table 2
Table 2: The composition of media
S. No. Ingradient Quantity S. No. Ingradient Quantity
1. Streptomycine sulphate 1.0 g 5. Agar 20.0 g
2. Peptone 5.0 g 6. Rose Bengal 0.033 g
3. Potassium dihydrogen Phosphate (KH2PO4) 1.0 g 7. Distilled water 1000 ml
4. Magesium suplhate (MgSO4 7H2O) 0.5 g 8. Glucose 2.0 g
Procedure: One milliliter of finally diluted soil sample was poured into 20 petridish in which 15 ml of distilled melted Mortine agar medium. After inoculation, the Petri dishes were incubated in BOD incubator at 25 + 20C for a period of one week to allow fungal growth. Fungal growth (colonies) were counted with the help of colony counter from the first appearance of the colony for a week of incubation.
Isolation of bacteria
Culture media: The composition of nutrient agar media was used for isolation of soil bacteria is given in Table 3.
Tables 3. The compostition of media.
S.No. Ingradient Quantity S.No. Ingradient Quantity
1. Glucose 1.0 g 3. Agar 20.0 g
2. Potassium orthophosphate 0.5 g 4. CaCO3 0.5 g
Procedure: The number of bacteria were isolated by dilution plate technique. Each Petri dish was poured with 15 ml of melted agar. Quickly diluted samples were inoculated and Petri plates were rotated clock and anticlock wise and left for solidification. Inoculated Petri plates were kept in the inverted position for a period of one week at 25+30C in BOD incubator. The bacterial colonies were counted carefully after incubation at both the surfaces. The number of bacteria per g of oven dry soil was calculated by following formula.
Bacteria per g dry soil = (average count ×dilution)/(dry weight of one gram moist soil)
Number of earthworm (per 0.15m3)
The number of earthworms were counted on soil surface and upto the depth of 15 cm.
Table 4: Effect of drip irrigation regimes and mulching on earth worms fungal and bacterial population of the soil
4.1 Earthworms population (per 0.15 m3)
Mulching Irrigation (IW/CPE
I1 I2 I3 I4 Mean
M1 20.21 17.13 16.88 15.00 17.31
M2 25.59 22.92 21.34 20.42 22.57
M3 21.50 21.00 19.04 18.08 19.91
Mean 22.43 20.35 19.09 17.83
CD (at 5%) I = 1.652 M = 1.429 I x M = NA
4.2 Fungal population (000 g-1 of soil)
Mulching Irrigation (IW/CPE
I1 I2 I3 I4 Mean
M1 55.75 62.21 163.33 209.84 122.78
M2 72.84 78.79 259.25 136.88 136.94
M3 82.59 99.17 181.22 39.34 100.58
Mean 70.39 80.06 210.27 128.67
CD (at 5%) I = 11.352 M = 9.832 I x M = 19.662
4.3 Bacterial population (m g-1 of soil)
Mulching Irrigation (IW/CPE
I1 I2 I3 I4 Mean
M1 8.75 6.34 4.52 3.65 5.83
M2 8.95 9.63 9.52 6.78 8.72
M3 6.69 2.50 2.01 1.53 3.18
Mean 8.13 6.16 5.35 3.99
CD (at 5%) I = 0.538 M = 0.470 I x M = 0.937
RESULT AND DISCUSSION
Earthworm
The average date illustrated in table (4.1) that earthworm population tends to increase (22.43) significantly in regime (I1) and there was a decline dramatically in response to deficit of water at I4 (IW/CPE = 0.4). It might be due to two major variables i.e. temperature and moisture affect the earthworm population. However, higher amount of water significantly increases the earthworm population.
Interaction of these two factors was found non significant on earthworm population. However, the maximum number of earthworm (25.59) was recorded in I1 (IW/CPE = 1.0) irrigation regime with paddy straw mulching (M2) it was followed by I2M2, I1M3, I3M2, and so forth.
The benefit of organic mulch (paddy straw) demonstrated maximum number of earthworm (22.57) followed by control and black polythene mulching. Organic mulches reduced tillage and maintain moisture which affects earthworm population (Edwards and Lofty 1982b; Werner and Dindal, 1989, Berry and Karlen, 1993)
Fungal population
It is revealed from Table (4.2) and Fig (1) that the fungal population in soil was significantly affected by irrigation regimes, mulching and their interaction.
The maximum number of fungal population (210.27) was counted in I3 (IW/CPE = 0.6) irrigation regime, it was followed by I4 (128.68), I2 (80.06) and I1 (70.39), however I1 and I2 was found statistically akin.
It is clear from the observation that paddy straw mulching produced significant maximum number of fungal population (136.94), strived by black polythene mulching (M1) and without mulching (M3) treatment.
The interaction effect of different irrigation regimes and mulching methods showed that the fungal population in the soil varied from 39.34 to 259.25 (Table 4.2). Among the different treatments combinations I3M2 produced significantly maximum number (259.25) of fungi per g of soil and it was accompanied by I4M1, I3M3, I3M1, and I4M1 and so on.
The highest fungal population in I3 irrigation indicates that the high moisture reduced the fungal population in the soil. Same findings are reported by Dhingra and Changes (1981).
Bacterial population
It is observed from Table (4.3) & Feg.No. 2 that bacterial population in soil was significantly influenced by irrigation regimes, mulching and their interaction.
The bacterial population was significantly maximum (8.13) in I1 irrigation regime and it was followed by I2, I3 and I4.
Similarly mulching with paddy straw showed significant maximum number of bacterial (8.72) which was followed by black polythene (M1 = 5.83) and control (M3 = 3.18).
The interaction effect of different irrigation regimes and mulching methods indicated that bacterial population per g of soil varied from 1.53 to 9.63 as illustrated in Table (4.2). Maximum number of bacteria was recorded in I2M2 and the same was followed by I3M2, I1M2, I1M1, I4M2 and so on. However, minimum number of bacteria was recorded in I4M3 treatment combination.
It has been attributed that the bacterial activities were maximum at higher level of moisture (I1) and decreased sharply as soil moisture decreased. It might be due to bacteria require high amount of moisture for their development in the soil. The results are also earlier report by Batthacharya and samedder (1976), Griffin (1983), Nicosia and Barbagallo (1987). It is well known that fungi and bacteria play an important role in soil fertility through their activities on organic matter decomposition and nutrient cycl. The present results also verified by the work of Baath and Soderstorm (1982). Marumata et al. (1991). Camprubi et al. (1995).
LITERATURE CITED
Baath, E.; soderstrom, B. (1982). Seasonal and spatial variation in fungal biomass in a forest soil. Soil Bio. Biochem. 14 : 353 – 358.
Berry, E.C.; Kalen, D.L. (1993). Composition of altenative forming system II. Earthworms population density and species diversity. Ame. J. Alt.ern. Agric., 8 : 21-26
Bhattacharya, M.; Smadhar, K.R. (1976). Epidemological studies on jute disease. Survival of Macrophomina Phascoli (Maubl). in soil. Plant and Soil, 44 : 27-36
Camprubi, C.; Calvet, C.; Estaum, V. (1995). Growth enhancement of citrus reshni after inoculation with Glomus intorardices and Trichoderma aurcovrinde and enzyme activity in potting mixes. Pland and Soil, 173 (2) : 233 – 238.
Dhingra, O.D.; Changas, D. (1981). Effect of soil temperature; moisture, and nitrogen and competilive saprohytic ability of Macrophomia phaseolino. Transaction of British Myeological Society, 77 (1) : 15 – 20.
Edwanrds, C.A.; Lafty, J.K. (1982 b). Nitrogen fertilizers and earthworms population in agriculture soil. Soil Bio. Biochem., 14 : 515 – 521.
Griffin, D.C. (1963). Soil physical factors and ecology of fungi III activity of fungi in relatively dry soil. Transaction of the British Mycological Society, 46 : 373 – 377.
Marumata, T.; Aaki, M.; Suzuk, Y.; Kusaka, T.; Kheng, J.W.C.; Higashi, T. (1991). Effect of rhizosphere conditions on the growth of strawberry I. Effect of nitrogen level, soil temperature and mulch. Bulletin of faculty of Agriculture, Yamaguchi University, No. 39 : 23 – 35.
Nicois, O.L.D.; Barbagallo, S.C. (1987). Irrigation experiment with practically treated waste water. Rivisa di ingegneria Agriaria, 18 (2) : 98 – 103
Werner, M.R.; Dinda, D.L. (1989). Earthworm community dynamics in convertional and low input agro ecosystem. Rev. Ecol. Biol. Soil, 26 : 427 – 437
