Reduction of the available phosphorus pool in field soils growing maize genotypes with extensive mycorrhizal development

2003 ◽  
Vol 83 (4) ◽  
pp. 737-744 ◽  
Author(s):  
A. Liu ◽  
C. Hamel ◽  
A. A. Elmi ◽  
T. Zhang ◽  
D. L. Smith
Keyword(s):  
Mycorrhizal Fungi ◽  
Arbuscular Mycorrhizal ◽  
Dry Mass ◽  
P Uptake ◽  
Available P ◽  
Extraradical Hyphae ◽  
Extractable P ◽  
P Content ◽  
Plant P Uptake ◽  
Mycorrhizal Development

Arbuscular mycorrhizal fungi (AMF) have a large enhancing effect on the P uptake capacity of host plants, which could make possible the production of high crop yields on soil with reduced level of available P, or could help reduce the P level in rich soils, thereby reducing the risk of P loss to the environment. A field experiment was conducted in Ste-Anne-de-Bellevue, Quebec, Canada, on a loamy sand in 1997 and a fine sandy loam in 1998 to assess the impact of indigenous AMF-maize hybrid combinations on soil available P level. The experiment had three factors organized in a split-split plot design. There were two soil fumigation levels (fumigated and non-fumigated) randomized in the main plots, three P fertilizer rates (0, 60, and 120 kg ha-1) randomized in the sub-plots and three maize (Zea mays L.) hybrids with contrasting genotypes [two newly developed leafy hybrids, Leafy normal stature (LNS) and Leafy reduced stature (LRS), and a commercial hybrid, Pioneer 3979 (P3979)], which were randomized in the sub-sub-plots. Soil extractable P, plant P content, plant dry mass, root colonization with AMF and extraradical hyphae were determined at the 6-leaf, 10-leaf, tasselling and silking stages of maize, and grain yield and total P in maize were determined at harvest. Soil fumigation to reduce AMF and P fertilization reduced the amount of indigenous mycorrhizal development in maize hybrids. The growth of LNS, the most mycorrhizae-dependent hybrid, was more supressed by fumigation than the growth of the other two hybrids. When the soil P level was low, plant dry mass, grain yield and total P content of LNS were higher in the non-fumigated plots than in the fumigated plots. Fumigation had a significant but smaller influence on soil extractable P level than on plant P uptake and growth. Soil extractable P was lower in non-fumigated plots than in fumigated plots from silking to the end of the growing season in 1997, only in non-fertilized plots growing LNS. Extraradical hyphae density was positively correlated with maize P uptake and negatively correlated with soil extractable P. This suggested that soil extractable P can be reduced through AMF-enhanced plant P uptake when soil available P conditions and host plant genotype are favourable to mycorrhizal development, and when P uptake enhancement is large. Key words: Arbuscular mycorrhizal fungi, maize hybrids, soil extractable P, P uptake, extraradical hyphae, root colonization, mycorrhizal dependency

scholarly journals Dual Inoculation With Arbuscular Mycorrhizal Fungi and Phosphorus Solubilizing Fungi Synergistically Enhances the Mobilization and Plant Uptake of Phosphorus From Meat and Bone Meal

2021 ◽  
Vol 1 ◽  
Author(s):  
Bhupinder Singh Jatana ◽  
Christopher Kitchens ◽  
Christopher Ray ◽  
Patrick Gerard ◽  
Nishanth Tharayil
Keyword(s):  
Arbuscular Mycorrhizal Fungi ◽  
Mycorrhizal Fungi ◽  
Arbuscular Mycorrhizal ◽  
P Uptake ◽  
Mineral Nutrient ◽  
Meat And Bone Meal ◽  
Bone Meal ◽  
Simultaneous Application ◽  
Plant P Uptake ◽  
P Mobilization

Phosphorus (P) is the second most important mineral nutrient for plant growth and plays a vital role in maintaining global food security. The natural phosphorus reserves [phosphate rock (PR)] are declining at an unprecedented rate, which will threaten the sustainable food supply in near future. Rendered animal byproducts such as meat and bone meal (MBM), could serve as a sustainable alternative to meet crop phosphorus demand. Even though nitrogen (N) from MBM is readily mineralized within a few days, >75% of the P in MBM is present as calcium phosphate that is sparingly available to plants. Thus, application of MBM with the aim of meeting crop N demand could result in buildup of P reserves in soil, which necessitates the need to improve the P mobilization from MBM to achieve higher plant P use efficiency. Here, we tested the potential of two microbial inoculum-arbuscular mycorrhizal fungi (AMF) and P solubilizing fungi (Penicillium bilaiae), in improving the mobilization of P from MBM and the subsequent P uptake by maize (Zea mays). Compared to the non-inoculated MBM control, the application of P. bilaiae increased the P mobilization from MBM by more than two-fold and decreased the content of calcium bound P in the soil by 26%. However, despite this mobilization, P. bilaiae did not increase the tissue content of P in maize. On the other hand, AMF inoculation with MBM increased the plant root, shoot biomass, and plant P uptake as compared to non-inoculated control, but did not decrease the calcium bound P fraction of the soil, indicating there was limited P mobilization. The simultaneous application of both AMF and P. bilaiae in association with MBM resulted in the highest tissue P uptake of maize with a concomitant decrease in the calcium bound P in the soil, indicating the complementary functional traits of AMF and P. bilaiae in plant P nutrition from MBM. Arbuscular mycorrhizal fungi inoculation with MBM also increased the plant photosynthesis rate (27%) and root phosphomonoesterase activity (40%), which signifies the AMF associated regulation of plant physiology. Collectively, our results demonstrate that P mobilization and uptake efficiency from MBM could be improved with the combined use of arbuscular mycorrhizal fungi and P. bilaiae.

Soil phosphorus depletion capacity of arbuscular mycorrhizae formed by maize hybrids

2003 ◽  
Vol 83 (4) ◽  
pp. 337-342 ◽  
Author(s):  
A. Liu ◽  
C. Hamel ◽  
S. H. Begna ◽  
B. L. Ma ◽  
D. L. Smith
Keyword(s):  
Plant Biomass ◽  
Arbuscular Mycorrhizal ◽  
Am Fungi ◽  
P Uptake ◽  
Maize Hybrids ◽  
Soil P ◽  
Extractable P ◽  
P Content ◽  
Total P ◽  
Extractable Soil

The ability of arbuscular mycorrhizal (AM) fungi to help their host plant absorb soil P is well known, but little attention has been paid to the effect of AM fungi on soil P depletion capacity. A greenhouse experiment was conducted to assess, under different P levels, the effects of mycorrhizae on extractable soil P and P uptake by maize hybrids with contrasting phenotypes. The experiment had three factors, including two mycorrhizal treatments (mycorrhizal and non-mycorrhizal), three P fertilizer rates (0, 40, and 80 mg kg-1) and three maize hybrids [leafy normal stature (LNS), leafy reduced stature (LRS) and a conventional hybrid, Pioneer 3979 (P3979)]. Extractable soil P was determined after 3, 6 and 9 wk of maize growth. Plant biomass, P concentration and total P content were also determined after 9 wk of growth. Fertilization increased soil extractable P, plant biomass, P concentration in plants and total P uptake. In contrast to P3979, the LNS and LRS hybrids had higher biomass and total P content when mycorrhizal. Mycorrhizae had less influence on soil extractable P than on total P uptake by plants. The absence of P fertilization increased the importance of AM fungi for P uptake, which markedly reduced soil extractable P under AM plants during growth. This effect was strongest for LNS, the most mycorrhizae-dependent hybrid, intermediate for LRS, and not significant for the commercial hybrid P3979, which did not respond to AM inoculation. Key words: Arbuscular mycorrhizal fungi, extraradical hyphae, maize hybrid,plant biomass, P uptake, soil extractable P

scholarly journals Colonization and Growth Effects of the Mycorrhizal Fungus Glomus intraradicies in a Commercial Nursery Container Production System

2000 ◽  
Vol 18 (4) ◽  
pp. 247-251
Author(s):  
F.T. Davies ◽  
J.A. Saraiva Grossi ◽  
L. Carpio ◽  
A.A. Estrada-Luna
Keyword(s):  
Production System ◽  
Mycorrhizal Fungi ◽  
Host Plants ◽  
Glomus Intraradices ◽  
Mycorrhizal Fungus ◽  
Arbuscular Mycorrhizal ◽  
Dry Mass ◽  
Fertility Level ◽  
Mycorrhizal Development ◽  
Container Production

Abstract The objectives of this research were to demonstrate that mycorrhiza can survive in a commercial nursery container production system, and enhance plant productivity. Four species were used as host plants [Nandina domestica ‘Moon Bay’, Loropetalum chinense variety Rubrum ‘Hinepurpleleaf’ Plumb delight®, Salvia gregii, and Photinia fraseri]. Plants were inoculated with arbuscular mycorrhizal fungi, Glomus intraradices, and grown in a commercial nursery in Texas. For the first 5.5 months, plants were grown in #1 cans containing either 3 kg cu m (5 lbs cu yd) or 4.2 kg cu m (7 lbs cu yd) 24N–4P205–8K20. For the final 6.5 months of the study, plants were in larger containers, all of which contained 4.2 kg cu m (7 lbs cu yd) 24N–4P2O5–8K2O. The commercial inoculum of Glomus intraradices only enhanced growth of N. domestica. The shoot dry mass of mycorrhizal N. domestica plants at 3 kg cu m was the same as non-colonized plants at the higher fertility level of 4.2 cu m. Intraradical hyphae development and colonization (total arbuscules, vesicles/endospores, hyphae) of L. chinense, N. domestica, and S. gregii increased at the higher fertility levels. S. gregii had the greatest mycorrhizal development and a 216% increase in hyphae development and colonization at the higher fertility level.

Effect of vesicular–arbuscular mycorrhizal fungi and phosphorus on the survival and growth of flowering dogwood (Cornus florida)

1986 ◽  
Vol 64 (5) ◽  
pp. 950-954 ◽  
Author(s):  
David M. Sylvia
Keyword(s):  
Mycorrhizal Fungi ◽  
Arbuscular Mycorrhizal ◽  
Dry Mass ◽  
Cornus Florida ◽  
P Nutrition ◽  
Flowering Dogwood ◽  
Vesicular Arbuscular ◽  
Field Nursery ◽  
Survival And Growth ◽  
Mycorrhizal Development

Mycorrhizal development and growth of flowering dogwood (Cornus florida L.) seedlings were investigated in a field nursery and glasshouse. Seedlings and associated soil were collected from April to November from a fumigated nursery bed that contained areas of both stunted and rapidly growing plants. The rate of mycorrhizal colonization and associated spore formation were greater on the rapidly growing seedlings. In a glasshouse test, dogwood seedlings were inoculated with chlamydospores of Glomus etunicatum, G. intraradices, or a control solution which contained microorganisms associated with the mycorrhizal fungi, and were fertilized weekly with Hoagland's solutions which had 0, 47, or 93 mg P∙L−1. After 12 weeks, seedlings inoculated with G. etunicatum had greater survival, shoot dry mass, and root fresh mass than seedlings inoculated with G. intraradices or the control. However, G. etunicatum did not affect the concentration or total uptake of P into shoots. This fungus can apparently enhance the survival and growth of dogwood seedlings without improving P nutrition.

scholarly journals Phosphorus acquisition and internal utilization efficiency in tropical maize genotypes

2008 ◽  
Vol 43 (7) ◽  
pp. 893-901 ◽  
Author(s):  
Sidney Netto Parentoni ◽  
Claudio Lopes de Souza Júnior
Keyword(s):  
Grain Yield ◽  
Selection Index ◽  
P Uptake ◽  
Utilization Efficiency ◽  
Available P ◽  
Phosphorus Acquisition ◽  
Tropical Maize ◽  
Maize Genotypes ◽  
Plant P Uptake ◽  
Soil Available P

The objective of this work was to determine the relative importance of phosphorus acquisition efficiency (PAE - plant P uptake per soil available P), and phosphorus internal utilization efficiency (PUTIL - grain yield per P uptake) in the P use efficiency (PUE - grain yield per soil available P), on 28 tropical maize genotypes evaluated at three low P and two high P environments. PAE was almost two times more important than PUTIL to explain the variability observed in PUE, at low P environments, and three times more important at high P environments. These results indicate that maize breeding programs, to increase PUE in these environments, should use selection index with higher weights for PAE than for PUTIL. The correlation between these two traits showed no significance at low or at high P environments, which indicates that selection in one of these traits would not affect the other. The main component of PUTIL was P quotient of utilization (grain yield per grain P) and not the P harvest index (grain P per P uptake). Selection to reduce grain P concentration should increase the quotient of utilization and consequently increase PUTIL.

scholarly journals FUNGOS MICORRÍZICOS ARBUSCULARES E DOSES DE FÓSFORO NO DESENVOLVIMENTO DE MUDAS DE GUANANDI

Nativa ◽  
2018 ◽  
Vol 6 (3) ◽  
pp. 246
Author(s):  
Edilson Nonato Da Silva ◽  
Aline Torquato Tavares ◽  
Cândida Pereira Da Silva ◽  
Tiago Alves Ferreira ◽  
João Victor Gonçalves Carline ◽  
...  
Keyword(s):  
Mycorrhizal Fungi ◽  
Arbuscular Mycorrhizal ◽  
Dry Mass ◽  
Mycorrhizal Colonization ◽  
University Campus ◽  
Experimental Station ◽  
Calophyllum Brasiliense ◽  
Shoot Mass ◽  
Different Levels ◽  
Forest Engineering

O experimento foi realizado na Estação Experimental de Engenharia Florestal do Campus Universitário de Gurupi, Universidade Federal do Tocantins (UFT), com objetivo de determinar a melhor dose de fósforo na presença de fungos arbusculares em mudas de guanandi (Calophyllum brasiliense Camb.) O delineamento experimental utilizado foi inteiramente casualizado com três repetições em esquema fatorial 6 x 2. Os tratamentos foram seis doses de fósforo (0; 400; 800; 1200; 1600 e 2000 g de P2O5 por m³) no substrato na presença e ausência de Fungos Micorrízos Arbusculares (FMAs). As características avaliadas foram altura das plantas, diâmetro do caule, massa seca da parte aérea (MSPA), massa seca da raiz (MSR), massa seca total (MST) e colonização micorrízica. Os diferentes níveis de adubação influenciaram a colonização micorrízica arbuscular. Nas doses 400 e 1600 g de fósforo por m3 de substrato observou-se maior porcentagem de colonização. A altura e o diâmetro das plantas foram significativamente afetados pela presença de P2O5. A massa seca da parte aérea e massa seca total não é afetada por doses de P2O5. O melhor desempenho das mudas de C. brasiliense ocorreu aos 90 dias com dose de 1.421 g de P2O5 por m3 de substrato.Palavras-chave: Calophyllum brasiliense Camb., adubação, micorrização. MYCORRHIZAL FUNGI AND PHOSPHORUS DOSES IN THE DEVELOPMENT OF GUANANDI SEEDLINGS ABSTRACT:The experiment was carried out at the Forest Engineering Experimental Station of the Federal University of Tocantins (UFT), University Campus of Gurupi, with the objective of determining the best dose of phosphorus in the presence of arbuscular fungi in guanandi (Calophyllum brasiliense Camb. The experimental design was completely randomized with three replicates in a 6 x 2 factorial scheme. The treatments were six doses of phosphorus (0, 400, 800, 1200, 1600 and 2000 g of P2O5 per m³) on the substrate in the presence and absence of Arbuscular mycorrhizal fungi (FMAs). The evaluated characteristics were plant height, stem diameter, shoot dry mass (MSPA), root dry mass (MSR), total dry mass (MST) and mycorrhizal colonization. The different levels of fertilization influenced arbuscular mycorrhizal colonization. At 400 and 1600 g of phosphorus per m3 of substrate, a higher percentage of colonization was observed. The height and diameter of the plants were significantly affected by the presence of P2O5. Dry shoot mass and total dry mass are not affected by P2O5 doses. The best performance of C. brasiliense seedlings occurred at 90 days with a dose of 1421 g of P2O5 per m3 of substrate.Keywords: Calophyllum brasiliense Camb., fertilization, mycorrhization. DOI:

scholarly journals Effect of Phosphate Fertilizer and Arbuscular Mycorrhizal Fungi on The Nutrient, Phosphateuptake and in Vitro Digestibility of Alfalfa

2016 ◽  
Vol 40 (3) ◽  
pp. 203 ◽  
Author(s):  
Bambang Suwignyo ◽  
Bela Putra ◽  
Nafiatul Umami ◽  
Cahyo Wulandari ◽  
Ristianto Utomo
Keyword(s):  
Organic Matter ◽  
Mycorrhizal Fungi ◽  
Dry Matter ◽  
Arbuscular Mycorrhizal ◽  
Phosphate Fertilizer ◽  
P Uptake ◽  
In Vitro Digestibility ◽  
P Fertilizer ◽  
Total P

This study aimed to determine the effect of arbuscular mycorrhizal fungi (AMF) and phosphate (P) fertilizer on the nutrient content, phosphate uptake and in vitro digestibility of alfalfa (Medicago sativa L.).The research was conducted at green house of Forage and Pastures Science Laboratory, Faculty of Animal Science Universitas Gadjah Mada. The experiment was arranged in Completely Randomized Design using 3x4 factorial patterns with four replications. The first factor was dosage of phosphate fertilizer SP 36 (0, 60, and 120 kg/ha). Second factor was the dosage of AMF (0, 0.8, 1.6, and 2.4kg/ha). The variable measured was nutrient contents (crude protein, dry matter, and organic matter), total P uptake and dry matter and organic matter in vitro digestibility. The results showed that the interaction of AMF and P fertilizer had no significant effect on crude protein and total P uptake, but highly significant effect on the parameters of dry matter, organic matter and dry matter and organic matter in vitro digestibility. 

scholarly journals The Phosphate Inhibition Paradigm: Host and Fungal Genotypes Determine Arbuscular Mycorrhizal Fungal Colonization and Responsiveness to Inoculation in Cassava With Increasing Phosphorus Supply

2021 ◽  
Vol 12 ◽  
Author(s):  
Ricardo Alexander Peña Venegas ◽  
Soon-Jae Lee ◽  
Moses Thuita ◽  
Deusdedit Peter Mlay ◽  
Cargele Masso ◽  
...  
Keyword(s):  
Mycorrhizal Fungi ◽  
Arbuscular Mycorrhizal ◽  
Field Trials ◽  
P Uptake ◽  
Fungal Colonization ◽  
P Availability ◽  
Terrestrial Plants ◽  
Soil Microbial ◽  
Arbuscular Mycorrhizal Fungal ◽  
P Supply

A vast majority of terrestrial plants are dependent on arbuscular mycorrhizal fungi (AMF) for their nutrient acquisition. AMF act as an extension of the root system helping phosphate uptake. In agriculture, harnessing the symbiosis can potentially increase plant growth. Application of the AMF Rhizophagus irregularis has been demonstrated to increase the yields of various crops. However, there is a paradigm that AMF colonization of roots, as well as the plant benefits afforded by inoculation with AMF, decreases with increasing phosphorus (P) supply in the soil. The paradigm suggests that when fertilized with sufficient P, inoculation of crops would not be beneficial. However, the majority of experiments demonstrating the paradigm were conducted in sterile conditions without a background AMF or soil microbial community. Interestingly, intraspecific variation in R. irregularis can greatly alter the yield of cassava even at a full application of the recommended P dose. Cassava is a globally important crop, feeding 800 million people worldwide, and a crop that is highly dependent on AMF for P uptake. In this study, field trials were conducted at three locations in Kenya and Tanzania using different AMF and cassava varieties under different P fertilization levels to test if the paradigm occurs in tropical field conditions. We found that AMF colonization and inoculation responsiveness of cassava does not always decrease with an increased P supply as expected by the paradigm. The obtained results demonstrate that maximizing the inoculation responsiveness of cassava is not necessarily only in conditions of low P availability, but that this is dependent on cassava and fungal genotypes. Thus, the modeling of plant symbiosis with AMF under different P levels in nature should be considered with caution.

scholarly journals Evaluasi produksi dan kualitas inokulum fungi mikoriza arbuskula yang diproduksi dengan teknik hidroponik pada rumput Brachiaria decumbens var. mullato

2018 ◽  
Vol 16 (2) ◽  
pp. 10
Author(s):  
A T Aryanto ◽  
P DMH Karti ◽  
I Prihantoro
Keyword(s):  
Host Plant ◽  
Mass Production ◽  
Mycorrhizal Fungi ◽  
Dry Matter ◽  
Irrigation System ◽  
Block Design ◽  
Arbuscular Mycorrhizal ◽  
P Uptake ◽  
Brachiaria Decumbens ◽  
Technique System

<p>ABSTRAK<br /><br />Pengembangan hijauan membutuhkan pupuk ramah lingkungan. Fungi Mikoriza Arbuskular (FMA) adalah asosiasi yang melibatkan jamur dan akar yang dianggap sebagai pupuk hayati untuk meningkatkan produktivitas tanaman dan toleran dari kondisi lingkungan. Ketersediaan FMA masih jarang, sehingga dibutuhkan produksi massal untuk dapat mendukung pengembangan hijauan. Tujuan dari penelitian ini adalah untuk menghasilkan inokulum AMF menggunakan sistem hidroponik dalam jumlah besar secara efektif. Penelitian ini dibagi menjadi 2 tahap. Rancangan Acak Kelompok Faktorial yang digunakan pada tahap pertama dengan faktor A adalah jenis sistem irigasi (Manual, Drip dan Nutrien Film Technique System (NFT)) dan B adalah larutan nutrisi (AB Mix dan Hyponex Red) dengan Pueraria javanica sebagai tanaman inang. Rancangan Acak Lengkap (RAL) dilakukan pada tahap kedua dengan menggunakan produksi inokulum FMA dari tahap pertama dengan Brachiaria decumbens var Mullato sebagai tanaman inang. Hasil penelitian menunjukkan bahwa interaksi antara sistem NFT dan AB Mix signifikan (P&lt;0,05) menghasilkan bahan kering tajuk, bahan kering akar dan spora paling tinggi. Semua tipe sistem irigasi dan nutrisi menunjukkan infeksi akar&gt;96%. FMA inokulasi di Brachiaria decumbes var Mulato signifikan(P &lt;0,05) pada bahan kering tajuk, kandungan N, kandungan P dan serapan P.</p><p><br />Kata kunci: Brachiaria decumbes, FMA, sistem Drip, sistem NFT, Pueraria javanica,</p><p><br />ABSTRACT</p><p>Forage mass production development requires environmental friendly fertilizer. Arbuscular Mycorrhizal Fungi (AMF) are mutualitic symbioses between plant and fungi that considered as natural biofertilizer with benefit to improve plant productivitity and environment stress tolerance. The availability of AMF is still low, so it takes mass production to be able to support forage development. The aim of the research was to produce AMF inoculum using hydroponic system in large quantities. This research divided into 2 stages. The factorial randomized block design was used for the first stage with A factor was type of irrigation system (Manual, Drip and Nutrient Film Technique System (NFT)) and B was the nutritional solution (AB Mix and Hyponex Red) using Pueraria javanica as host plant. Completely randomized design was conducted for the second stage by using AMF inoculum production from first stage using Brachiariadecumbens var Mullat as host plant. The best result was a combination beetwen NFT system and AB Mix significantly (P&lt;0.05) produce highest shoot dry matter, root dry matter and spore production. All type of irrigation system and nutrition showed root infection &gt;96%. AMF inoculation in Brachiariadecumbes var Mulato was significant different (P&lt;0.05) on shoot dry matter, N content, P content and P uptake.</p><p><br />Keywords: AMF, B. decumbes, Drip system, NFT system, P. javanica,</p>

EVALUATION DU PHOSPHORE ASSIMILABLE DES SOLS ACIDES AVEC DIFFERENTES METHODES D’EXTRACTION EN RELATION AVEC LE RENDEMENT DE L’AVOINE ET LES PROPRIETES DU SOL

1985 ◽  
Vol 65 (1) ◽  
pp. 47-60 ◽  
Author(s):  
M. GIROUX ◽  
T. SEN TRAN
Keyword(s):  
P Uptake ◽  
Available P ◽  
Anion Exchange Resins ◽  
P Fixation ◽  
Exchangeable Ca ◽  
Plant P Uptake ◽  
Fixation Capacity ◽  
Exchange Resins ◽  
Bray 1 ◽  
Extractable Al

The objective of this study was to evaluate different available P extracting methods in relation with soil properties, oat yield and plant P uptake. Six chemical extractants (Bray-1, Bray-2, new Mehlich, North Carolina DA-4, DA-10, and Olsen) and two anion exchange resins (F− and HCO3−) were compared on 42 acid soils. The DA-4, DA-10, new Mehlich, and HCO3− resin methods showed the best correlation with oat yield and plant P uptake. The Bray-1, Bray-2 methods were significantly less correlated than the other methods. The HCO3− resin was better than F− resin to predict plant P uptake and yield. Available P levels as determined by these eight methods were classified poor, medium and rich by the Cate and Nelson procedure. Oxalate extractable Al, pH (NaF), pH (H2O), exchangeable (Ca + Mg), forms of P, maximum P fixation capacity and soil texture have great influence on the plant P uptake. Soil organic matter content and oxalate-extractable Fe had significantly less important an effect. The Bray-1 and Bray-2 methods were the most affected by soil properties especially oxalate-extractable Al. The P-HCl/P-DAF ratio proposed by Mehlich to identify forms of soil P indicated that seven soils contain predominantly Ca-P and 21 soils with predominantly Al-P and Fe-P. This ratio was related with oxalate extractable Al (r = − 0.32*), pH NaF (r = − 0.59**), pH H2O (r = 0.52**) and exchangeable Ca + Mg (r = 0.55**). The maximum P fixation capacity (M) ranged from 150 to 4200 μg P/g soil and was closely related with oxalate-extractable Al (r = 0.81**), pH NaF (r = 0.74**), pH H2O (r = − 0.36*) and Mehlich ratio (r = − 0.33*). The maximum P buffering capacity (Mb) of soils was also measured and showed the best correlation with oxalate-extractable Al (r = 0.84**) and pH NaF (r = 0.53**). Key words: Soil testing, available P, anion exchange resins, P fixation, oxalate-Al, forms of P

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