Identification of organic acids produced during rice straw decomposition and their role in rock phosphate solubilization

The production of organic acids and changes during decomposition of rice straw amended with tricalcium phosphate (TCP) and Udaipur rock phosphate (URP) were studied under laboratory conditions. The organic C content of rice straw decreased and total N increased with time, resulting in a decrease in C:N ratio as the decomposition progressed. The pH decreased to acidic range in all the treatments on day 15, but became alkaline again later on. Soluble P increased at 15 days after incubation, declined later during decomposition, and was highest in the treatments containing TCP and Aspergillus awamori inoculation. Citric, oxalic, formic and maleic acids were detected during decomposition of rice straw and maximum amounts were present on day 15. Citric and oxalic acids were responsible mainly for P solubilization from TCP and URP; generally, citric acid was the most effective in P solubilization.

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Soil Chemistry and Cucumber (Cucumis sativus L.) Yield as Influenced by 16 Years of Composted Poultry Litter Addition

Journal of Agricultural Science ◽

10.5539/jas.v10n1p325 ◽

2017 ◽

Vol 10 (1) ◽

pp. 325

Author(s):

Hebert D. A. Abobi ◽

Armand W. Koné ◽

Bernard Y. Koffi ◽

Saint Salomon F. Diahuissié ◽

Stanislas K. Loukou ◽

...

Keyword(s):

Soil Fertility ◽

Growth Parameters ◽

Block Design ◽

C:N Ratio ◽

Poultry Litter ◽

Growth And Yield ◽

Soil Parameters ◽

Total N ◽

Organic C ◽

Litter Addition

Poultry litter is increasingly used as organic amendment in market gardening in Côte d’Ivoire. To know about the sustainability of this practice, its impacts on soil quality should be known. This study aimed at assessing the effect on soil fertility of composted poultry litter addition for 16 years following two distinct ways, and identifying soil parameters driving cucumber yield. Trials were laid out in a Fisher randomized block design with 3 treatments replicated 5 times each: Control (C), Surface-applied compost (SAC) and Buried compost (BC). Soil (0-20 cm) chemical characteristics and cucumber growth and yield parameters were measured. Values of all parameters were higher with compost addition compared to the control, except for the C:N ratio. SAC and BC showed similar values of organic C, total N, CEC, pH and available phosphorus. However, Ca2+, Mg2+, K+ and base saturation were higher in SAC than in BC. Relative to values in the control, the greatest changes in soil parameters were observed with exchangeable cations, followed by soil organic matter. Soil organic C and total N concentrations have doubled in SAC while Ca2+, Mg2+, and K+ increased at greater rate (702.4, 400.9 and 186.67% respectively). Also, cucumber growth parameters were the highest with compost addition compared to the control. Significant effect of the compost application way on cucumber was also observed: collar diameter, leaf area and fresh fruit yield in SAC (0.72±0.02 cm, 258.9±12.3 cm2, 11.1±1.3 t ha-1, respectively) were higher than in BC (0.56±0.01 cm, 230.2±2.5 cm2, 5.4±0.5 t ha-1 respectively). Fruit yields in SAC and BC were four times and twice higher than in the control (2.6±0.3 t ha-1), respectively. Cucumber growth parameters were determined by soil concentration in Mg2+ while yield was determined by Ca2+. Composted poultry litter should be promoted for a sustainable soil fertility management in vegetable farming systems.

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Soil Fertility Properties and Rice Biomass Production Under Three Rice Farming Systems at Vertisols Sambung Macan Sub District, Sragen Regency

Journal of Tropical Soils ◽

10.5400/jts.2019.v24i1.17-23 ◽

2019 ◽

Vol 24 (1) ◽

pp. 17

Author(s):

. Sukristiyonubowo ◽

Damasus Riyanto ◽

Sugeng Widodo

Keyword(s):

Rice Straw ◽

Block Design ◽

Farming Systems ◽

Rice Farming ◽

Organic System ◽

Total N ◽

Organic C ◽

Rice Grains ◽

Conventional Systems ◽

Rice Residues

The farmers realize that green revolution technology with high inputs is no longer sustainable. They want to move to other rice farming systems. The aim of research was to study soil chemical-physical characteristics and rice productions under three rice farming systems. This study was conducted in Vertisols at Sambung Macan Sub District, Sragen Regency, arranged in a randomized complete block design with three replications and as the treatments was an organic, semi organic and conventional rice systems. One kilo gram composites soil samples of 0-20 cm in depth were collected from five random sampling points of every site and taken in March 2017, before soil preparation. Rice biomass productions namely rice grains, rice straw and rice residues were harvested in the end of June 2017. The results indicated that in organic field, the soil chemical-physical fertility was superior to that of in semi organic and conventional and semi organic system was better than conventional in terms of soil pH, organic C and total N, P and K total, soil bulk density, particle density, soil porosity and permeability. Similar finding was observed for rice biomass productions. The rice grains yields were 7.53 ± 0.85, 6.60 ± 0.15 and 5.77 ± 0.71, rice straw were 7.97 ± 0.47, 7.63 ± 0.21 and 6.93 ± 0.25 and forrice residues were 4.20 ± 0.10, 3.30 ± 0.20 and 3.25 ± 0.35 Mgs ha-1 season-1 in organic, semi organic and conventional systems, respectively.Compared to the conventional system, the organic increased about 31 %, 15% and 29 % for rice grains, rice straw and rice residues, respectively. Comparing semi organic to conventional, the improvement was 14 %, 10 % and 2 % for rice grains, rice straw and rice residues, respectively. This short term research concluded that organic rice farming was superior to both semi organic and conventional systems, but the long term effect of organic need to be further evaluated.

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Simulation of soil carbon dynamics in Australia with {\sc Roth C}

10.5194/ismc2021-91 ◽

2021 ◽

Author(s):

Raphael Viscarra Rossel ◽

Juhwan Lee ◽

Mingxi Zhang ◽

Zhongkui Luo ◽

YingPing Wang

Keyword(s):

C:N Ratio ◽

Clay Content ◽

Natural Environments ◽

Soil Organic C ◽

Total N ◽

Organic C ◽

Continental Scale ◽

C Stocks ◽

C Decomposition ◽

Soil Measurements

We simulated soil organic carbon (C) dynamics across Australia with the Rothamsted carbon model ({\sc Roth C}) by connecting new spatially-explicit soil measurements and data with the model. This helped us to bridge the disconnection that exists between datasets used to inform the model and the processes that it depicts. We compiled publicly available continental-scale datasets and pre-processed, standardised and configured them to the required spatial and temporal resolutions. We then calibrated {\sc Roth C} and run simulations to estimate the baseline soil organic C stocks and composition in the 0--0.3~m layer at 4,043 sites in cropping, modified grazing, native grazing, and natural environments across Australia. We used data on the C fractions, the particulate, mineral associated, and resistant organic C (POC, MAOC and ROC, respectively) to represent the three main C pools in the {\sc Roth C} model's structure.&#160; The model explained 97--98\% of the variation in measured total organic C in soils under cropping and grazing, and 65\% in soils under natural environments. We optimised the model at each site and experimented with different amounts of C inputs to simulate the potential for C accumulation under constant and chainging climate in a 100-year simulation. Soils under native grazing were the most potentially vulnerable to C decomposition and loss, while soils under natural environments were the least vulnerable. An empirical assessment of the controls on the C change showed that climate, pH, total N, the C:N ratio, and cropping were the most important controls on POC change. Clay content and climate were dominant controls on MAOC change. Consistent and explicit soil organic C simulations improve confidence in the model's estimations, contributing to the development of sustainable soil management under global change.&#160;

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Soil properties following long-term application of stockpiled feedlot manure containing straw or wood-chip bedding under barley silage production

Canadian Journal of Soil Science ◽

10.4141/cjss2013-087 ◽

2014 ◽

Vol 94 (3) ◽

pp. 389-402 ◽

Cited By ~ 6

Author(s):

J. J. Miller ◽

B. W. Beasley ◽

C. F. Drury ◽

X. Hao ◽

F. J. Larney

Keyword(s):

Soil Properties ◽

C:N Ratio ◽

Wood Chip ◽

Water Soluble ◽

Bedding Material ◽

Total N ◽

Organic C ◽

Silage Production ◽

Total Organic C

Miller, J. J., Beasley, B. W., Drury, C. F., Hao, X. and Larney, F. J. 2014. Soil properties following long-term application of stockpiled feedlot manure containing straw or wood-chip bedding under barley silage production. Can. J. Soil Sci. 94: 389–402. The influence of long-term land application of stockpiled feedlot manure (SM) containing either wood-chip (SM-WD) or straw (SM-ST) bedding on soil properties during the barley (Hordeum vulgare L.) silage growing season is unknown. The main objective of our study was determine the effect of bedding material in stockpiled manure (i.e., SM-WD vs. SM-ST) on certain soil properties. A secondary objective was to determine if organic amendments affected certain soil properties compared with unamended soil. Stockpiled feedlot manure with SM-WD or SM-ST bedding at 77 Mg (dry wt) ha−1 yr−1 was annually applied for 13 to 14 yr to a clay loam soil in a replicated field experiment in southern Alberta. There was also an unamended control. Soil properties were measured every 2 wk during the 2011 and 2012 growing season. Properties included water-filled pore space (WFPS), total organic C and total N, NH4-N and NO3-N, water-soluble non-purgeable organic C (NPOC), water-soluble total N (WSTN), denitrification (acetylene inhibition method), and CO2 flux. The most consistent and significant (P≤0.05) bedding effects on soil properties in both years occurred for total organic C, C:N ratio, and WSTN. Total organic C and C:N ratio were generally greater for SM-WD than SM-ST, and the reverse trend occurred for WSTN. Bedding effects on other soil properties (WFPS, NH4-N, NO3-N, NPOC) occurred in 2012, but not in 2011. Total N, daily denitrification, and daily CO2 flux were generally unaffected by bedding material. Mean daily denitrification fluxes ranged from 0.9 to 1078 g N2O-N ha−1 d−1 for SM-ST, 0.8 to 326 g N2O-N ha−1 d−1 for SM-WD, and 0.6 to 250 g N2O-N ha−1 d−1 for the CON. Mean daily CO2 fluxes ranged from 5.3 to 43.4 kg CO2-C ha−1 d−1 for SM-WD, 5.5 to 26.0 kg CO2-C ha−1 d−1 for SM-ST, and from 0.5 to 6.8 kg CO2-C ha−1 d−1 for the CON. The findings from our study suggest that bedding material in feedlot manure may be a possible method to manage certain soil properties.

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Soil Quality Dynamic and Rice Production of Three Different Rice Farming Systems in Sragen District, Central Java Province

Jurnal Tanah dan Iklim ◽

10.21082/jti.v44n2.2020.101-108 ◽

2020 ◽

Vol 44 (2) ◽

pp. 101

Author(s):

Sukristiyonubowo Sukristiyonubowo ◽

Sugeng Widodo ◽

Arif Anshori ◽

Damasus Riyanto

Keyword(s):

Soil Quality ◽

Rice Straw ◽

Green Revolution ◽

Farming Systems ◽

Rice Farming ◽

Organic System ◽

Total N ◽

Organic C ◽

Rice Grains ◽

Rice Residues

Abstract. The farmers realize that green revolution technology with high inputs is no longer sustainable, expensive and the yield decrease. Some farmers move to organic rice farming, semi organic, and the rest remain doing conventional rice farming. The research aim was to monitor soil quality dynamic and rice productions under three rice farming systems. This study was conducted in Vertisols at Sambung Macan Sub District, Sragen Regency. The treatments were arranged in randomized complete block design with three replications. The treatments was organic, semi organic and conventional rice farming systems. The results indicated that in organic field, the soil quality in 2019 was more superior than in semi organic and conventional in 2018 and 2017 and soil qualities of semi organic system was better than conventional in terms of soil chemical, physical and biological including soil pH, organic C and total N, P and K total, soil bulk density, particle density, soil porosity and permeability. Similar finding was observed for rice biomass productions in 2019. In 2019 the rice grains yields were 12.68, 7.43 and 7.0, rice straw were 7.25, 6.55 and 6.25 and forrice residues were 4.15, 3.20 and 3.15 tons ha-1 season-1 in organic, semi organic and conventional systems, respectively. Compared to the conventional system, the organic increased about 81%, 16% and 32% for rice grains, rice straw and rice residues, respectively. Compared to conventional, semi organic improved about 6%, 5% and 2% for rice grains, rice straw and rice residues, respectively.Abstrak. Petani menyadari bahwa green revolution technology tidak lumintu, biaya produksi mahal dan hasil panen menurun. Sebagian petani beralih ke budidaya padi organik, semi organik dan sebagian bertahan pada sistem konvensional dengan perbaikan. Penelitian bertujuan untuk mengetahui perkembangan kualitas tanah dan hasil brangkasan padi pada sistem padi organik, semi organik dan konvensional. Penelitian dilaksanakan pada tahun 2017, 2018 dan 2019 pada tiga sistem budidaya padi di Kecamatan Sambung Macan, Sragen. Penelitian menggunakan rancangan acak kelompok, dengan tiga ulangan dan sebagai perlakuan tiga budidaya padi. Hasil penelitian menunjukkan bahwa kualitas tanah pada budidaya organik pada tahun 2019 lebih unggul dibandingkan semi organik dan konvensional pada tahun 2018 dan 2017. Begitu juga kualitas tanah pada semi organik pada 2019 lebih baik dibandingkan budidaya konvensional. Hasil brangkasan padi pada budidaya organik tahun 2019 lebih tinggi dibandingkan dengan tahun 2018 dan 2017 baik pada budidaya padi semi organik maupun konvensional. Hasil gabah, jerami dan sisa panen dari ketiga sistem budidaya padi pada tahun 2019 masing masing sebesar 12,68; 7,43 dan 7,0; jerami 7,25; 6,55 dan 6,25 dan sisa panen 4,15; 3,20 dan 3,15 ton ha-1 musim-1 untuk budidaya padi organik, semi organik dan konvensional. Dibandingkan dengan konvensional sistem, budidaya organik meningkat sekitar 81%, 16% and 32% untuk gabah, jerami dan sisa panen. Dibandingkan dengan konvensional, budidaya semi organik meningkat 6%, 5% and 2% untuk gabah, jerami dan sisa panen.

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Efficient lignin decomposing microbial consortium to hasten rice-straw composting with moderate GHGs fluxes

10.21203/rs.3.rs-203292/v1 ◽

2021 ◽

Author(s):

Pradeep Kumar Dash ◽

Soumya Ranjan Padhy ◽

Pratap Bhattacharyya ◽

Ankita Pattanayak ◽

Soumya Routray ◽

...

Keyword(s):

Rice Straw ◽

Large Scale ◽

Microbial Consortium ◽

Lignin Content ◽

C:N Ratio ◽

Straw Decomposition ◽

Moisture Management ◽

Carbon Nitrogen Ratio ◽

Nitrogen Ratio ◽

Rice Straw Decomposition

Abstract We hypothised that lignin decomposition microbial consortium would make rice-straw decomposition faster as straw contain around 15–24% lignin. In this study, we isolated lignin degrading microbes from four natural sources and based on their ability towards lignin degradation four microbial strains and their combination (2 bacteria (LB 8, LB 18) and 2 fungi (LF 3, LF 9) were selected for rice straw decomposition. During straw decomposition greenhouse gases emission, enzymatic activities (β-glucosidase, cellulase, laccase), reduction in lignin content, weight loss and carbon nitrogen ratio (C:N) were quantified. The β-glucosidase, cellulase and laccase activities were higher in LB 18 + LF 3 consortium as compared to others. The lignin content was also decreased (8.9–9.5 to 6.6–7.9%) continuously from initial to 28th days of composting under LB 18 + LF 3. We found the microbial consortium LB 18 + LF 3 decomposed the rice straw faster as indicated by reduction of C:N ratio and reduction of lignin, hemicellulose and cellulose contents of 60, 19.2, 41.5 and 10.3%, respectively at 28th day from initial compare to other strains/consortium. However, higher, CH4 and CO2 fluxes were observed at 28th days after composting (1.36 and 200.7 mg m− 2 h− 1) with no significant trend in N2O flux. Further, the consortium identified could be tested for in-situ straw decomposition with proper moisture management to evaluate its potential in field condition. Therefore, we conclude that use of lignin decomposing microbial consortium has the potential to hasten the composting of rice straw in large scale, so viable option to reduce the menace of straw burning.

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Simulation of soil carbon dynamics in Australia under a framework that better connects spatially explicit data with Rᴏᴛʜ C

10.5194/bg-2020-150 ◽

2020 ◽

Author(s):

Juhwan Lee ◽

Raphael A. Viscarra Rossel ◽

Zhongkui Luo ◽

Ying Ping Wang

Keyword(s):

C:N Ratio ◽

Clay Content ◽

Spatially Explicit ◽

Natural Environments ◽

Soil Organic C ◽

Total N ◽

Organic C ◽

Soil C ◽

Continental Scale ◽

C Stocks

Abstract. We simulated soil organic carbon (C) dynamics across Australia with the Rothamsted carbon model (Rᴏᴛʜ C) under a framework that connects new spatially-explicit soil measurements and data with the model. Doing so helped to bridge the disconnection that exists between datasets used to inform the model and the processes that it depicts. Under this framework, we compiled continental-scale datasets and pre-processed, standardised and configured them to the required spatial and temporal resolutions. We then calibrated Rᴏᴛʜ C and run simulations to predict the baseline soil organic C stocks and composition in the 0–0.3 m layer at 4,043 sites in cropping, modified grazing, native grazing, and natural environments across Australia. The Rᴏᴛʜ C model uses measured C fractions, the particulate, humus, and resistant organic C (POC, HOC and ROC, respectively) to represent the three main C pools in its structure. The model explained 97–98 % of the variation in measured total organic C in soils under cropping and grazing, and 65 % in soils under natural environments. We optimised the model at each site and experimented with different amounts of C inputs to predict the potential for C accumulation in a 100-year simulation. With an annual increase of 1 Mg C ha−1 in C inputs, the model predicted a potential soil C increase of 13.58 (interquartile range 12.19–15.80), 14.21 (12.38–16.03), and 15.57 (12.07–17.82) Mg C ha−1 under cropping, modified grazing and native grazing, and 3.52 (3.15–4.09) Mg C ha−1 under natural environments. Soils under native grazing were the most potentially vulnerable to C decomposition and loss, while soils under natural environments were the least vulnerable. An empirical assessment of the controls on the C change showed that climate, pH, total N, the C:N ratio, and cropping were the most important controls on POC change. Clay content and climate were dominant controls on HOC change. Consistent and explicit soil organic C simulations improve confidence in the model's predictions, contributing to the development of sustainable soil management under global change.

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TITONIA DAN JERAMI PADI YANG DIKOMPOSKAN TERHADAP CIRI KIMIA TANAH DAN PRODUKSI JAGUNG PADA ULTISOL

Jurnal Solum ◽

10.25077/jsolum.16.1.11-18.2019 ◽

2019 ◽

Vol 16 (1) ◽

pp. 11

Author(s):

Gusnidar Gusnidar ◽

Annisa Fitri ◽

Syafrimen Yasin

Keyword(s):

Key Words ◽

Rice Straw ◽

Soil Ph ◽

Chemical Properties ◽

Dry Weight ◽

Corn Production ◽

Total N ◽

Organic C ◽

West Sumatra ◽

Level Of Significance

Ultisol is broad suboptimal soils, need to be developed to increase for foods and animal feeds, but properties of physics and chemistry by the soils bad. This research was aimed to studied the influence of compost derived from titonia plus rice straw in improving chemical properties of Ultisol and corn production. This researh was conducted in glasshouse and Soil Laboratory of Agriculture Faculty, Andalas University, Padang, West Sumatra, Indonesia from January to July 2017. The experiment consisted of 5 treatments (0.00; 2.50; 5.00;7.50; 10.00 tonha-1. with 3 replications. Soil data resulted were compared to the soil criteria, while corn data were statistically analyzed the variance and continued using DNMRT at 0.05 level of significance, if F-calculated > F-table. The results of research showed that optimum dosage for repaired chemical properties of 7,50 tonha-1. It dosage soil pH 6,18 unit; available P by 17,64ppm; CEC by 18,38cmol(kg)-1; organic-C by 1,27%, total-N by 0,23%; K-exch. by 0,49cmol(kg)-1; Ca-exch. by 2,63 cmol(kg)-1; Mg-exch. by 0,57cmol(kg)-1 dan Na-exch. by 0,39cmol(kg)-1, with dry weight of seed by 85,48gpot-1; dry weight of straw by 75,84gpot-1 and dry weight of 100 seed by 25,50g. Key words : Compost derived from titonia plus rice straw, corn, Ultisol.

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THE SULPHUR STATUS OF EASTERN CANADIAN PRAIRIE SOILS: THE RELATIONSHIP OF SULPHUR, NITROGEN AND ORGANIC CARBON

Canadian Journal of Soil Science ◽

10.4141/cjss85-018 ◽

1985 ◽

Vol 65 (1) ◽

pp. 179-186 ◽

Cited By ~ 9

Author(s):

L. D. BAILEY

Keyword(s):

Sandy Loam ◽

C:N Ratio ◽

High Potential ◽

Canadian Prairie ◽

Canadian Prairies ◽

Total N ◽

Organic C ◽

Prairie Soils ◽

Relationship Of ◽

The Relationship

Surface and subsurface samples of 17 of the most agriculturally important soils of the eastern Canadian prairies were analyzed for total S, sulphate S, total N and organic C. The soils varied in texture from sandy loam to clay loam. Fifteen of the soils were of the Chernozemic order, one was Brunisolic and the other Luvisolic. The subgroups included were Orthic Blacks, Gleyed Rego Blacks, Orthic Dark Greys, Eluviated Eutric Brunisol and Orthic Luvisol. The total S of the soils decreased with depth and was significantly correlated with total N and with organic C. The sulphate sulphur extracted with 0.1 M CaCl2 accounted for an average of 2.6% of the total S in each of the three soil depths analyzed. The calculated N:S and C:N ratios averaged 8.3 and 1.25 (0–15 cm), 7.2 and 14.1 (15–30 cm), and 6.5 and 11.0 (30–60 cm), respectively. The N:S ratios, and to limited extent the C:N ratios, were used to describe the sulphur status of the soils. Soil with N:S and C:N ratios 6.0 and 12.5 (0–15 cm), 5.2 and 13.5 (15–30 cm), 4.7 and 11.4 (30–60 cm), respectively, could have a high potential to supply sulphate S to plants and may not be deficient in plant-available S. Soils with N:S and C:N ratios of 8.7 and 13.5 (0–15 cm), 7.2 and 14.7 (15–30), 6.3 and 11.2 cm (30–60 cm), respectively, may be deficient in sulphur for some crops. However, they may have a high potential to convert total S to sulphate S. Soils with N:S and C:N ratio of 12.4 and 11.2 (0–15 cm), 11.1 and 13.0 (15–30), 10.2 and 9.9 (30–60 cm), respectively, may be deficient in plant-available S and could have a low potential for conversion of total S to sulphate S. Key words: Sulphur status of soils; potential available sulphur

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Application of Different Organic Acids on Phosphorus Solubility from Rock Phosphate

Journal of Horticulture and Plant Research ◽

10.18052/www.scipress.com/jhpr.2.43 ◽

2018 ◽

Vol 2 ◽

pp. 43-48 ◽

Cited By ~ 1

Author(s):

Aftab Jamal ◽

Azam Khan ◽

Muhammad Sharif ◽

Hifsa Jamal

Keyword(s):

Citric Acid ◽

Humic Acid ◽

Oxalic Acid ◽

Organic Acids ◽

Rock Phosphate ◽

Ph Value ◽

Ph Values ◽

P Concentration ◽

Extractable P ◽

Oxalic Acids

An incubation experiment was conducted on P solubilization from rock phosphate (RP) through different organic acids such as oxalic acid, citric acid, acetic acid, humic acid and sulphur in the laboratory of the Department of Soil and Environmental Sciences, KP Agricultural University Peshawar during fall 2011. The experiment was laid in a complete randomize design. There were three replications with six treatments. The organic acids were used at the rate of 2 % for 50 g RP in 250 ml conical flasks. These samples were kept in an incubator at 250c for four months and analysed for Mehlic-3 extractable P and pH values after 20 days interval. Statiscal analyses were made and maximum P concentration of 1.52% was observed in the treatment of oxalic acid mixed with RP followed by the treatments of RP mixed with humic acid with P concentration of 0.368% (Fig. 1). Rapid increases in P solubility from RP by mixing with oxalic acids were noted up to 60thdays of incubation period and then remained stable after this period. Solubilization of P from RP by mixing with other organic acids was inconsistent. The pH in treatment of citric acid mixed with RP was noted as 5.64, followed by the treatments of oxalic acid with pH values of 6.31. A dramatic increase in pH value of 9.33 was observed in the treatment of RP mixed with humic acid. It is because the humic acid contains sodium salt and sodium hummate causes increase in its pH values.

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