Crop (Maize) Response to Direct Application of Local Phosphate Rock on Selected Acid Soils of Tanzania

2007 ◽  
Vol 38 (1) ◽  
pp. 93-106 ◽  
Author(s):  
M. M. Msolla ◽  
J. M. R. Semoka ◽  
C. Szilas ◽  
O. K. Borggaard
2013 ◽  
Vol 18 (1) ◽  
pp. 1
Author(s):  
. Nurjaya ◽  
Dedi Nursyamsi

Source of P fertilizer which is used by farmers in upland acid soils area is generally acidulated phosphate rock (PR), such as tripel super phosphate (TSP), super phosphate 36% P2O5 (SP-36), as well as partial acidulated phosphate rock (PAPR) which contain 10-30% P2O5. Their effectiveness, however, varies and depends on the soil and plant types. Phosphate rock fertilizers have a high prospects for acid soils because its effectiveness equals to the SP-36, cheaper, slow release, and its application can also leave  the residual P in the soil that available for plants for next few seasons. Field experiment aimed to study the effectiveness of direct application of PR at upland acid soils and its effect on soil available-P as well as maize (Zea mays L.) yield was conducted in Acid Inceptisols of Ciampea, Bogor in wet season years 2008/2009. The experiment was arranged by a Randomized Completely Block Design with 3 replications. Maize of P-12 variety was used as a plant indicator. The treatment consisted of 6 levels of phosphate rock: 0, 20, 30, 40, 50, and 60 kg P ha-1, as well as one level of SP-36 40 kg P ha-1 as standard fertilizer. In addition, urea of 300 kg ha-1 and KCl of 100 kg ha-1 were used as basal fertilization. The result showed that the application of PR in the amount ranging from 20 to 60 kg P ha-1 increased total-P and available-P, and pH, decreased exchangeable Al in the soils as well as increased maize straw and grain. Phosphate rock  application at 40 kg P ha-1 level was equally effective as SP-36 in the tested soils. Critical level of soil P for maize grown in the soil was 675 and 5.00 mg P2O5 kg-1 extracted with HCl 25% and Bray I, respectively. The requirement of P for maize grown in the soil to achieve maximum profit was 38 kg P ha-1 and 17.5 kg P  ha-1 or equivalent to PR of 583 and 268 kg ha-1 in low (soil P < critical level) and high (soil P > critical level) soil P status,  respectively.Keywords: Direct application, phosphate rock, soil available-P, upland acid soils.[How to Cite: Nurjaya and D Nursyamsi. 2013. Effectiveness of Direct Application of Phosphate Rock in Upland Acid Inceptisols Soils on Available-P and Maize Yield. J Trop Soils 18 (1): 1-9. doi: 10.5400/jts.2013.18.1.1] [Permalink/DOI: www.dx.doi.org/10.5400/jts.2013.18.1.1]  


2021 ◽  
Vol 648 (1) ◽  
pp. 012175
Author(s):  
A F Siregar ◽  
Husnain ◽  
I W Suastika ◽  
N P S Ratmini ◽  
I A Sipahutar ◽  
...  

1996 ◽  
Vol 46 (3) ◽  
pp. 235-239 ◽  
Author(s):  
Hu Hong-Qing ◽  
Li Xue-Yuan ◽  
Liu Jung-Fu ◽  
Xu Feng-Lin ◽  
Liu Jung ◽  
...  

2020 ◽  
Vol 5 (1) ◽  
pp. 1
Author(s):  
Alex Boateng ◽  
Prof. Emmanuel Owusu- Bennoah

Purpose: In recent years, phosphate rock (PR) for direct application has been tested in tropical acid soils as a potential alternative to conventional water-soluble P fertilizers like Single Superphosphate (SSP) and Triple Superphosphate (TSP). However, direct application of PR with low reactivity does not always give satisfactory results. Legume and cereal crops represent a strategy that can be used to solubilize P from some of these unreactive PRs. The objective of this study was to assess the availability of P from unreactive Togo Phosphate Rock (TPR) relative to TSP by six (6) crop species in two Ghanaian soils. Methodology:  The study was conducted in the greenhouse of the Crop Science Department, University of Ghana. Three P rates, 0mg, 50mg and 100mg P of TPR and TSP were applied to a kilogram of soil per pot in the two soil series. Randomized Complete Block Design was used to do the analyses. Results/Findings: Application of TSP resulted in higher dry matter and P uptake irrespective of the soil type. Among the legumes, cowpea gave the highest dry matter yield. Fairly, a similar trend was obtained with the application of TPR. Among the cereals, the average P uptake by sorghum from TPR was the highest, followed by maize and millet in the Nzema soil. In the Adenta series, P uptake by maize was the highest, followed by sorghum and millet. Phosphorus (P) uptake by the cereals from TPR was generally better in the Adenta than the Nzema soil. Unique contribution to theories, practice and policy: Results show increasing the rate of TPR to 100mg P/pot resulted in an increase in dry matter yield and P uptake in both soils, but was inferior to 100mg P/pot TSP application. Consequently, the rate of application of TPR should always be high if farmers want the best from their investments. Again, the low relative agronomic effectiveness of TPR for all the crops, proved the low reactivity of the material and its subsequent low performance compared with the water-soluble P. The low reactivity and the high molar mass of PO43-/CO32- of the TPR will always make it difficult for P to be made available from the TPR despite the acidity of the soil, the high density of the crops and the ability of the tested crops to exude organic acids, which facilitate phosphorus availability from TPR, therefore making TPR unsuitable for direct application.


Soil Research ◽  
1999 ◽  
Vol 37 (1) ◽  
pp. 115 ◽  
Author(s):  
Daniel E. Dodor ◽  
Yoshihiro Tokashiki ◽  
Kazuhiro Oya ◽  
Moritaka Shimo

The ability of phosphate rock (PR) to dissolve rapidly in soil is a primary concern in its direct application as P fertiliser. The dissolution of 4 PR materials (Togo, South Africa, Florida, Morocco PRs) in 15 soil samples in Okinawa was investigated in a closed-incubation system for 7 days. The fertilisers were mixed with the soils at rates of addition of 600–1200 µg Ca/g soil. The extent and rate of dissolution of the PRs were determined by measuring the increase in extractable Ca of the fertilised soils compared with unfertilised soils, i.e. the delta Ca (ΔCa) technique. Generally, the amounts of dissolution of 3 of the PRs were very low (mean 6·7% for Togo PR, 13·6% for South Africa PR, and 20·8% for Florida PR). However, Morocco PR dissolved to an appreciable extent (mean 60·8%), suggesting that it can be an alternative P source, especially in the red and yellow soils of Okinawa. Soil properties identified as affecting dissolution were different for the different PRs. In order to predict the suitability of Morocco PR for Okinawan soils, the extent of its dissolution was related to soil properties in a multiple regression analysis. Results indicated that the best regression model for predicting the amount of dissolution was the combination of pH, Ca saturation, and Truog P (r2 = 0·55**). Measured values of percentage dissolution of Morocco PR were significantly correlated with calculated percentages (r = 0·844***), indicating that the equation obtained could offer a rapid estimation of amount of dissolution of Morocco PR in Okinawan soils.


2016 ◽  
Vol 8 (1) ◽  
pp. 10
Author(s):  
Yusdar Hilman ◽  
Anuar Abdul Rahim ◽  
Mohamed Hanafi Musa ◽  
Azizah Hashim

Many of the agricultural soils in Indonesia are acidic and low in both total and available phosphorus which severely limits their potential for crops production. These problems can be corrected by application of chemical fertilizers. However, these fertilizers are expensive, and cheaper alternatives such as phosphate rock (PR) have been considered. Several soil factors may influence the dissolution of PR in soils, including both chemical and physical properties. The study aimed to identify PR dissolution factors and evaluate their relative magnitude. The experiment was conducted in Soil Chemical Laboratory, Universiti Putra Malaysia and Indonesian Center for Agricultural Land Resources Research and Development from January to April 2002. The principal component analysis (PCA) was used to characterize acid soils in an incubation system into a number of factors that may affect PR dissolution. Three major factors selected were soil texture, soil acidity, and fertilization. Using the scores of individual factors as independent variables, stepwise regression analysis was performed to derive a PR dissolution function. The factors influencing PR dissolution in order of importance were soil texture, soil acidity, then fertilization. Soil texture factors including clay content and organic C, and soil acidity factor such as P retention capacity interacted positively with P dissolution and promoted PR dissolution effectively. Soil texture factors, such as sand and silt content, soil acidity factors such as pH, and exchangeable Ca decreased PR dissolution.


Sign in / Sign up

Export Citation Format

Share Document