The Effect of Organic Matter (Centrosema pubescens) and Rock Phosphate Application on the Activity of Phosphatase and P Fraction of Latosol Soil in Darmaga, Bogor

One of the problems of acid soils such as Latosol is very low in P-availabi/ity due to high P-j'vcation in those soils. Sincesoils is deficiency of P, adaptation of plants and microorganisms to overcome deficiency of P in soil is by producing phosphatase. Phosphatase. is an enzyme that able to catalize transformation of organic P to inorganic P, and produced by plant roots, residual of plants and microorganisms. Organic mailer as a source of P besides N and energy formicroorganisms, and then rock phosphate as an alternative P fertilizer were used in this research. The objective of theresearch was to study the effect of organic matter (Centrocema pubescent) and rock phosphate application on phosphataseactivity and P fraction of Latosol soil from Darmaga, Bogor. The experiment was designed by completely randomized designwith two factors and three replications. The first factor was application of organic matter with the rate of 0, 2.5, and 5 %, and the second factor was application of rock phosphate with the rate of 0, 20, and 40 ppm P. Soil equivalent to four hundred grams of oven dried soil, organic matter, and rock phosphate were mixed based on the treatments of the experiment, and were placed in plastic pots, and then were incubated for 8 weeks period After incubation period, the soil were air dried and analyzed for phosphatase activity, available P, and organic and inorganic P. The result showed that organic mailer increased activities of acid and alkaline phosphatase, organic and inorganic-P of soil. On the other hand, rocle phosphate increased inorganic P but decreased activities of acid phosphatase,. Application of organic matter or rock phosphate on activity of acid phosphatase was higher (2.3-2.6 times) than on alkaline phosphatase. There was no effect of combinationbetween organic matter and rock phosphate on the activity of phosphatase and organic/inorganic P. Combination betweenorganic matter and rock phosphate Significantly affected available P. In each rates of rock phosphate given, the increasing rate of organic matter increased available P in their interactions, on the contrary, in each rates of organic matter, the increasing rate of rock phosphate did not affect available P in their interactions. However it was tended to decrease in therate of 40 ppm P.

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Relationship of soil phosphorus fractions to phosphorus soil tests and fertilizer response

Canadian Journal of Soil Science ◽

10.4141/s02-079 ◽

2003 ◽

Vol 83 (4) ◽

pp. 443-449 ◽

Cited By ~ 6

Author(s):

R. H. McKenzie ◽

E. Bremer

Keyword(s):

Available P ◽

Soil Test ◽

Strongly Correlated ◽

P Fractions ◽

Soil Tests ◽

Fertilizer Response ◽

Inorganic P ◽

Soil P ◽

P Fertilizer ◽

Soil Test P

Soil tests for available P may not be accurate because they do not measure the appropriate P fraction in soil. A sequential extraction technique (modified Hedley method) was used to determine if soil test P methods were accurately assessing available pools and if predictions of fertilizer response could be improved by the inclusion of other soil P fractions. A total of 145 soils were analyzed from field P fertilizer experiments conducted across Alberta from 1991 to 1993. Inorganic P (Pi) removed by extraction with an anion-exchange resin (resin P) was highly correlated with the Olsen and Kelowna-type soil test P methods and had a similar relationship with P fertilizer response. No appreciable improvement in the fit of available P with P fertilizer response was achieved by including any of the less available P fractions in the regression of P fertilizer response with available P. Little Pi was extractable in alkaline solutions (bicarbonate and NaOH), particularly in soils from the Brown and Dark Brown soil zones. Alkaline fractions were the most closely related to resin P, but the relationship depended on soil zone. Inorganic P extractable in dilute HCl was most strongly correlated with soil pH, reflecting accumulation in calcareous soils, while Pi extractable in concentrated acids (HCl and H2SO4) was most strongly correlated with clay concentration. A positive but weak relationship as observed between these fractions and resin P. Complete fractionation of soil P confirmed that soil test P methods were assessing exchangeable, plant-available P. Key words: Hedley phosphorus fractionation, resin, Olsen, Kelowna

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Organic management and legume presence maintained phosphorus bioavailability in a 17-year field crop experiment

Renewable Agriculture and Food Systems ◽

10.1017/s1742170513000380 ◽

2013 ◽

Vol 30 (3) ◽

pp. 211-222 ◽

Cited By ~ 2

Author(s):

Courtney Gallaher ◽

Sieglinde S. Snapp

Keyword(s):

Organic Matter ◽

Soil Properties ◽

Particulate Organic Matter ◽

P Uptake ◽

Field Crop ◽

Inorganic P ◽

Soil P ◽

P Fertilizer ◽

Term Management

AbstractLegumes have been shown to enhance bioavailability of phosphorus (P) from sparingly soluble pools, yet this functional trait remains underutilized in agriculture, and is untested at decadal scales. Management and legume presence effects on temporal soil properties were evaluated in a 17-year field crop experiment using soil samples collected in 1992, 2000 and 2006. Management systems compared included: (1) conventional corn–soybean–wheat rotation (C–S–W), (2) organic (C–S–W+red clover), (3) alfalfa and (4) early successional field. To evaluate the effects of long-term management versus recent management (residues and P fertilizer) on P and bio-availability to soybean, subplots of soybean were established with and without P-fertilizer (30 kg P ha−1), and compared to subplots and main plot with the long-term system. We evaluated soil properties (C, total P, Bray extractable inorganic P, particulate organic matter phosphorus) and soybean P uptake, biomass and yield. Recent fertilizer P inputs had no detectable influence on soil P, and total soil P stayed stable at ~350 mg P kg−1, whereas inorganic P (Pi) declined from an initial value of 54 to an average of 35 mg P kg−1. A P balance was constructed and showed a net loss of −96.7 kg P ha−1 yr−1 for the organic system, yet Bray-Pi and soybean P uptake were maintained under organic production at similar levels to the conventional, fertilized system. Particulate organic matter P was 57, 82 and 128% higher in organic, alfalfa and successional treatments, respectively, compared to conventional. A similar pattern was observed for soil C, soybean yield and bioavailable P, which were 20–50% higher in the organic, alfalfa and successional systems relative to conventional. This study provides evidence that long-term management history influences bioavailability of P.

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Phosphorus transformations in acid light-textured soils treated with dry swine manure

Canadian Journal of Soil Science ◽

10.4141/s03-049 ◽

2005 ◽

Vol 85 (1) ◽

pp. 75-87 ◽

Cited By ~ 34

Author(s):

Lotfi Khiari ◽

Léon E. Parent

Keyword(s):

Organic Matter ◽

Swine Manure ◽

Organic Ligand ◽

Acid Soils ◽

P Availability ◽

P Fractionation ◽

Soil C ◽

Soil P ◽

Metal Organic ◽

P Fraction

Organic matter can sorb P in acid soils through metal-organic matter-phosphate complexes. The pyrophosphate extractable Al and Fe and soil C contents were hypothetized to influence P partitioning in Ferro-Humic Podzols. Reaction of added P may be mitigated by adding lime or organic matter as dry swine manure (DSM) together with mineral P fertilizers. Three soils had 40 to 50 g kg-1 of soil organic matter (SOM) content, and 76 to 140 mmol (Al + Fe)pyro kg-1. A peaty soil phase had 200 g SOM kg-1, and 58 mmol (Al + Fe)pyro kg-1. Rates of monoammonium phosphate were 0, 27, 69, and 144 kg P ha-1 in a simulated fertilizer band. Rates of DSM and lime were 800 and 185–369 mg per 35 mL of soil, respectively. After 6 wk of incubation, soil P was fractionated sequentially into aluminium bound P (Al-P), iron bound P (Fe-P), and loosely bound P. Total P, desorbed P and organic P were determined in separate subsamples. A proportion of 79–92% of added P was recovered as Al-P and Fe-P in the three low SOM soils, compared to 51–61% in the high SOM soil. The DSM increased loosely bound P from 25 to 34% in the high SOM soil and from 4.8 to 5.9% in low SOM soils. With DSM, the proportion of desorbed P was much higher in the high (70%) than in low SOM (22%) soils. Compared to the non-amended treatment, lime showed no significant effect on any P fraction but desorbed P. The DSM increased P availability in the fertilizer band considerably more in the soil having the lowest (Al + Fe)pyro/C ratio. Key words: P fractionation, organic ligand, P sorption, fertilizer band

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Phosphorus forms and related soil chemistry of Podzolic soils on northern Vancouver Island. II. The effects of clear-cutting and burning

Canadian Journal of Forest Research ◽

10.1139/x00-099 ◽

2000 ◽

Vol 30 (11) ◽

pp. 1726-1741 ◽

Cited By ~ 46

Author(s):

Barbara J Cade-Menun ◽

Shannon M Berch ◽

Caroline M Preston ◽

L M Lavkulich

Keyword(s):

Organic Matter ◽

Vancouver Island ◽

Available P ◽

Resonance Spectroscopy ◽

Inorganic P ◽

Clear Cut ◽

Podzolic Soils ◽

Clear Cutting ◽

Slash Burning

When cedar-hemlock (CH) forests of northern Vancouver Island are clear-cut and replanted, growth of replanted trees is often poor. This growth check can be overcome with nitrogen (N) and phosphorus (P) fertilization, suggesting that it may be because of deficiencies of these elements. A widely used site-preparation tool in these forests is slash burning. Because fire is known to alter nutrient cycling in forests, this burning may be contributing to the problem of poor seedling growth. Thus, the objective of this study was to compare P in forest floor and soils from clear-cut CH stands 10 years, 5 years, and immediately after burning to P concentrations and forms in undisturbed old growth CH stands. Analytical methods included extraction and digestion procedures, fractionation and 31P nuclear magnetic resonance spectroscopy. Soon after burning, an "ashbed effect" was noted, with increased pH and higher concentrations of available P in surface soil horizons. Available P concentrations and pH returned to preburn levels within 10 years. However, destruction of organic matter appeared to disrupt illuviation processes throughout the soil profile, producing long-term changes in organic matter, organic P, and organically complexed Fe and Al in lower mineral horizons. Total P concentrations were unchanged, but there was a shift from organic to inorganic P forms and changes in P forms with time at depth in the profile. These changes in P distribution and movement in the soil may contribute to the growth check observed in these forests.

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The Changes of P-fractions and Solubility of Phosphate Rock in Ultisol Treated by Organic Matter and Phosphate Rock

Journal of Tropical Soils ◽

10.5400/jts.2012.v17i3.203-210 ◽

2013 ◽

Vol 17 (3) ◽

pp. 203-210

Author(s):

Sri Djuniwati ◽

Budi Nugroho ◽

Heru Bagus Pulunggono

Keyword(s):

Organic Matter ◽

Phosphate Rock ◽

Acid Soils ◽

Essential Elements ◽

Imperata Cylindrica ◽

Soil Reaction ◽

P Fractions ◽

Phosphate Rock Dissolution ◽

Randomized Design ◽

P Fraction

Phosphorus (P) is one of the essential elements for plant, however, its availability is mostly very low in acid soils. It is well documented that application of phosphate rock and organic matter are able to change the level of availability of P-form in acid soils. The objective of the research were to evaluate the changes of P-fractions ( resin-P, NaHCO3-Pi, and NaHCO3-Po) and phosphate rock dissolution which were induced by application of organic matter (Imperata cylindrica, Pueraria javanica, dan Colopogonium mucunoides) and phosphate rock in Utisol Lampung. The experiment was designed in a completely randomized design with three factors and three replications. The first factor was the types of organic matter (I. cylindrica, P. javanica, and C. mucunoides), the second factor was the rate of organic matter (0, 2.5, and 5%), and the third factor was the rate of phosphate rock (0, 40, and 80 mg P kg-1). The results showed that in the rate of 0 and 1% organic matter, the type of organic matter did not affect P-fraction of NaHCO3-Pi, but in the rate of 2.5 and 5%, NaHCO3-Pi due to application of P. javanica, and C. mucunoides higher than due to application of I. cylindrica. However, the increasing rate of organic matter increased NaHCO3-Pi. Then, P-fraction of Resin-Pi was affected by the type of organic matter, the rate of organic matter, and the rate of phosphate rock, respectively. P-fraction of resin-Pi due to application of P. javanica, and C. mucunoides was higher than due to application of I. cylindrica, but the effect of P. javanica, and C. mucunoides was not different. Increasing the rate of organic matter and phosphate rock increased P-fraction of resin-Pi and NaHCO3-Pi, but P-fraction of NaHCO3-Po was not affected by all treatments. Meanwhile, dissolution of phosphate rock was affected by the kind of organic matter and soil reaction. In the rate of 5% organic matter, dissolution of phosphate rock by application of I. cylindrica (70%) was higher than P. javanica (26.6%), and C. mucunoides (33.5%), but in the rate of 1%, the effect of I. cylindrica , P. javanica, and C. mucunoides were not different.Keywords: C. mucunoides; I. cylindrica; P. javanica; phosphate rock; P-fractions[How to Cite: Djuniwati S, B Nugroho, and HB Pulunggono. 2012. The Changes of P-fractions and Solubility of Phosphate Rock in Ultisol Treated by Organic Matter and Phosphate Rock. J Trop Soils, 17: 203-210. doi: 10.5400/jts.2012.17.3.203][Permalink/DOI: www.dx.doi.org/10.5400/jts.2012.17.3.203]

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The Effect of Organic Matter (Pueraria javanica) and Rock Phosphate on the Growth and P-uptake of Corn Plant (Zea mays) in Andisol Pasir Saronggae

Jurnal Ilmu Tanah dan Lingkungan ◽

10.29244/jitl.5.1.17-22 ◽

2003 ◽

Vol 5 (1) ◽

pp. 17-22

Author(s):

S Djuniwati ◽

A Hartono ◽

L.T Indriyati

Keyword(s):

Organic Matter ◽

Dry Matter ◽

Rock Phosphate ◽

P Uptake ◽

Corn Plant ◽

Randomized Design ◽

Two Factors ◽

Plastic Bag ◽

Department Faculty ◽

Water Holding

Phosphor (P) is the second esensial element after nitrogen which is needed by plants, however, its ava/i!ahi/ity is aproblem in vulcanic ash soils such as Andisol. The objective of the research was to study the effect of organic matter(Puerariajavanica) and rock phosphate to the growth and P-uptake of corn plant in Andisol Pasir Sarongge. The experiment was conducted in the greenhouse of Soil Department, Faculty of Agriculture, Bogor Agriculture University.The design of the experiment was completely randomized design with two factors and three replications. The firstfactor was the rates of organic matter (0, 2.5%, and 5%) and the second factor was the rates of rock phosphate (0, 40 mg Plkg, and 80 mg Plkg), therefore there were 27 of treatments of experiment. Three kilogram of soil samples were put in the plastic bag and mixed with combination of organic matter and rock phosphate based on the treatments and then incubatedfor 4 week periods. After incubation, five seeds of corn were planted, and then were selected and left three plants after one week period. The soil moisture was maintained to water holding capacity.The results of the study showed that after 4 weeks of planting (4WAP), addition of organic matter increased plantheight, dry matter and P- uptake of corn plant. However, the effect between the rate of 2.5% and 5% of organic matter to those variables above were not significantly different. The increased of plant height (4WAP), dry matter, and P-uptake due to addition of organic matter were in the range of 32-41%, 68-105%, and 84-92%, respectively. Meanwhile. addition of rock phosphate. and combination of organic matter and rock phosphate did not affect those variables.

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EFEKTIVITAS BEBERAPA DEPOSIT FOSFAT ALAM INDONESIA SEBAGAI PUPUK SUMBER FOSFOR TERHADAP PERTUMBUHAN BIBIT KELAPA SAWIT PADA TANAH ULTISOLS

Jurnal Penelitian Tanaman Industri ◽

10.21082/jlittri.v16n4.2010.165-171 ◽

2020 ◽

Vol 16 (4) ◽

pp. 165

Author(s):

A. KASNO ◽

SUDIRMAN SUDIRMAN ◽

M.T. SUTRIADI

Keyword(s):

Oil Palm ◽

Rock Phosphate ◽

Block Design ◽

Acid Soils ◽

Dry Weight ◽

Root Weight ◽

Trunk Diameter ◽

P Content ◽

P Fertilizer ◽

And Control

ABSTRAKPenelitian bertujuan untuk mempelajari pengaruh fosfat alam asalIndonesia terhadap kadar P dalam tanah dan pertumbuhan kelapa sawit.Penelitian dilaksanakan di rumah kaca Balai Penelitian Tanah di Laladon,Bogor dari bulan Juni sampai Desember 2009, dengan menggunakanrancangan percobaan acak kelompok dengan 8 perlakuan dan diulang 5kali. Perlakuan yang dicoba adalah 5 P-alam asal Indonesia, ditambahSuperphos, P-alam Tunisia, dan kontrol. Tanah yang digunakan adalahTypic Kanhapludults dan Typic Plinthudults yang diambil dari Lampung,dengan tanaman indikator adalah kelapa sawit. Hasil penelitianmenunjukkan bahwa pemupukan P nyata meningkatkan diameter batang,tinggi tanaman, berat akar dan berat kering tanaman. Pemupukan P denganSuperphos memberikan peningkatan yang lebih tinggi daripada pemu-pukan dengan fosfat alam. Efektivitas pupuk P-alam pada TypicPlintudults lebih rendah dibandingkan pada Typic Kanhapludults. PupukP-alam dari Indonesia sama efektifnya dengan P-alam Tunisia untukpemupukan tanaman kelapa sawit. Pemupukan P dengan Superphos padatanaman kelapa sawit nyata meningkatkan kadar P tanah lebih tinggidaripada kadar P tanah yang dipupuk P-alam. Pemberian pupuk P belumberpengaruh terhadap kadar P dalam akar dan tanaman kelapa sawit dalampembibitan.Kata kunci: Elaeis guinensis, kelapa sawit, tanah masam, fosfat alamABSTRACTEffectiviness of several rock phosphate deposites fromIndonesia as P fertilizer sources on the growth of oilpalmseedling on ultisolsThe aim of this research was to study the effect of rock phosphatefrom Indonesia on P content on the soil and growth of oil palm. Thisresearch was conducted at the glass house of Indonesian Soil ResearchInstitute, Laladon Bogor from June to December 2009, using randomizedcomplete block design (RCBD) with 8 treatments and 5 replicates. Thetreatments were 5 types of Indonesia rock phosphate, Superphos, Tunisiarock phosphate, and control. The soils used were Typic Kanhapudults andTypic Plinthudults, and oil palm nursery as plant indicator. The resultshowed that P fertlizer was significant to increase trunk diameter, plantheight, root weight, and plant dry weight. Superphos fertilizer increasedtrunk diameter, plant height, root weight, and plant dry weigth better thanrock phosphate. Effectivity of rock phosphate at Typic Plinthudults waslower than at Typic Kanhapludults. Indonesian rock phosphate waseffective for fertilizing oil palm, as well as Tunisia rock phosphate. Pfertilization using Superphos significantly increased P soil content and wasbetter than rock phosphate. Application of rock phosphate did notinfluence P contents in root and plant of oil palm in nursery.Key words: Elaeis guinensis, oil palm, acid soils, rock phosphate

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Rhizospheric P and K in forest soil manipulated with ammonium sulfate and water

Canadian Journal of Soil Science ◽

10.4141/s95-070 ◽

1997 ◽

Vol 77 (4) ◽

pp. 515-523 ◽

Cited By ~ 12

Author(s):

Stephen Clegg ◽

George R. Gobran

Keyword(s):

Organic Matter ◽

Ammonium Sulfate ◽

Norway Spruce ◽

Tree Growth ◽

Limiting Factor ◽

Organic P ◽

Inorganic P ◽

Soil Fractions ◽

Extractable P ◽

P Fraction

This study shows how the stress manipulations, ammonium sulfate, drought and irrigation changed the P and K status of three soil fractions (bulk soil, rhizosphere and soil-root interface) from E, Bh and Bs horizons of a Norway spruce stand in southwestern Sweden. The results indicate that dynamic linkages exist between the three soil fractions and tree growth. Accumulation rather than depletion of P and K were observed in the vicinity of the roots which we attribute primarily to accumulated organic matter and high rates of mineralization. Relative depletion of P and K around roots resulted from treatments that stimulated tree growth and P and K uptake. The ratio of organic P, the largest extractable P fraction, to inorganic P indicated that organic P is an important P resource when inorganic P is heavily utilized in treatments where growth has increased. There are indications that K supply was reduced by stimulating growth with ammonium sulfate and irrigation, suggesting that K rather than P can become the second limiting factor to growth at this site after N. Key words: Organic matter, available P and K, relative depletion, Norway spruce, ecosystem manipulation, conceptual model, environmental stress

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Exogenous phosphorus compounds interact with nitrogen availability to regulate dynamics of soil inorganic phosphorus fractions in a meadow steppe

10.5194/bg-2019-173 ◽

2019 ◽

Author(s):

Heyong Liu ◽

Ruzhen Wang ◽

Hongyi Wang ◽

Yanzhuo Cao ◽

Feike A. Dijkstra ◽

...

Keyword(s):

Nitrogen Availability ◽

Plant Biomass ◽

Octacalcium Phosphate ◽

Inorganic Phosphorus ◽

Phosphorus Compounds ◽

Calcareous Grassland ◽

Available P ◽

Olsen P ◽

P Fertilizer ◽

P Fraction

Abstract. Here we investigated the effects of P compounds (KH2PO4 and Ca(H2PO4)2) with different addition rates of 0, 20, 40, 60, 80 and 100 kg P ha−1 yr−1 and NH4NO3 addition (0 and 100 kg N ha−1 yr−1) on soil labile (Olsen-P), moderate-cycling and recalcitrant inorganic phosphorus (IP) fractions in a calcareous grassland of northeastern China. Soil moderate-cycling IP, not readily available to plants but transforming into available P quickly, include variscite (Al-P), strengite (Fe-P), dicalcium phosphate (Ca2-P) and octacalcium phosphate (Ca8-P); recalcitrant fractions include hydroxylapatite (Ca10-P) and occluded P (O-P). Soil labile and moderate-cycling IP fractions and total P significantly increased with increasing P addition rates, with higher concentrations detected for KH2PO4 than for Ca(H2PO4)2 addition. Combined N and P treatments showed lower moderate-cycling IP fractions compared to ambient N conditions due to enhanced plant productivity. Moderate-cycling IP was mainly regulated by aboveground plant biomass with KH2PO4 addition, while by soil pH and plant biomass with addition of Ca(H2PO4)2. Ca(H2PO4)2 addition significantly increased the soil recalcitrant IP (Ca10-P) fraction, while KH2PO4 addition showed no impact on it. A significant positive correlation was detected between soil moderate-cycling IP fractions and soil Olsen-P which illustrated that moderate-cycling IP fractions were important sources for available P. Our results suggest that moderate-cycling IP fractions are essential for grassland P biogeochemical cycling and chemical form of P fertilizer should be considered during fertilization management for maintaining soil available P.

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Improving Phosphate Efficiency by Phosphate Solubilizing Bacteria and Organic Matter Estimated by Radio Isotop (32P) Technique in Some Soils

Journal of Tropical Soils ◽

10.5400/jts.2012.v17i3.245-252 ◽

2013 ◽

Vol 17 (3) ◽

pp. 245-252

Author(s):

Arie Mudjiharjati ◽

Tri Candra Setiawati ◽

Martinus Harsanto Pandutama

Keyword(s):

Organic Matter ◽

Rock Phosphate ◽

Available P ◽

P Availability ◽

Phosphate Solubilizing Bacteria ◽

Soil Matrix ◽

Natural Materials ◽

Residual P ◽

Phosphate Solubilizing ◽

P Absorption

Phosphorous (P) contents in many soils are varies highly along with their ability to provide available P to plant growth. Soils may contain very high in total P, but low in available P due to high P adsorbed by soil matrix and all their adsorbing agents. This research which using natural materials was aimed to increase P availability in some high-P absorption soils. The natural materials utilized for extracting P were organic matter, P extracting bacterial, and rock phosphate. Those materials were interacted to high P absorption soils which were: Oxisol, Inceptisol, and Andisol. The detail objectives of this research were: (1) to study the potential of P-extracting agents (organic matter, and P-extracting bacteria) in releasing P of three high P- absorption soils; (2) to quantify the -age of P coming from the treatments; (3) to calculate the efficiency of P utilization by plant; and (4) to quantify Residual P in soils. The P mobility was analyzed by radioisotope technique using KH232PO4 carrier free solution. The results showed that adding soil organic matter increased the available P by 15.24% in Oxisol, 40.18 in Inceptisol, and by 7.34% in Andisol. Plant sorption toward P from % P used efficiency(%-PUE) up to 60 days was still very low, 0.65 to 9.34%. This was in accordance with the residual P in soils which were still quite high ranging from 94% to 96% in Andisol, 91%97% in Inceptisol, and 96%-98% in Oxisol. The implication of the results of this research, however, is that the application of natural materials in improving soil P availability provides a longtimeresidual effect which could give benefit to the following crops.Keywords: Andisols; Inceptisol; Oxisols; P. diminuta; PUE; rock phosphate[How to Cite: Mudjiharjati A, TC Setiawati and MH Pandutama. 2012. Improving Phosphate Efficiency by Phosphate Solubilizing Bacteria and Organic Matter Estimated by Radio Isotop (32P) Technique in Some Soils. J Trop Soils, 17 (3) : 245-252. doi: 10.5400/jts.2012.17.3.245][Permalink/DOI: www.dx.doi.org/10.5400/jts.2012.17.3.245]

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