IMMEDIATE AND RESIDUAL EFFECTS OF LIME AND PHOSPHORUS FERTILIZER ON SOIL ACIDITY AND MAIZE PRODUCTION IN WESTERN KENYA

2013 ◽  
Vol 50 (1) ◽  
pp. 128-143 ◽  
Author(s):  
P. O. KISINYO ◽  
C. O. OTHIENO ◽  
S. O. GUDU ◽  
J. R. OKALEBO ◽  
P. A. OPALA ◽  
...  
Keyword(s):  
Soil Ph ◽  
Residual Effects ◽  
Available P ◽  
Fertilizer Rate ◽  
Maize Production ◽  
Western Kenya ◽  
Exchangeable Al ◽  
Soil Available P ◽  
P Fertilizer ◽  
Fertilizer Recovery

SUMMARYSoil acidity and phosphorus (P) deficiency are some of the major causes of low maize yields in Kenya. This study determined the immediate and residual effects of lime and P fertilizer on soil pH, exchangeable aluminium (Al), available P, maize grain yield, agronomic P use and P fertilizer recovery efficiencies on a western Kenya acid soil. The treatments were: P fertilizer (0, 26 and 52 kg P ha−1as triple super phosphate) and lime (0, 2, 4 and 6 tons lime ha−1) applied once at the beginning of the study. A burnt liming material with 92.5% calcium carbonate equivalent was used. Soil samples were analysed prior to and after treatment application. The site had low soil pH–H2O (4.9), available P (2.3 mg kg−1), total N (0.17%), high Al (2.0 cmol kg−1exchangeable Al and 29% Al saturation). Lime reduced soil pH and exchangeable Al, leading to increased soil available P. Lime at 2, 4 and 6 tons ha−1maintained soil pH ≥ 5.5 for 2, 3 and 4 years, respectively. The study observed that the recommended P fertilizer rate (26 kg P ha−1) for maize production in Kenya was inadequate to raise soil available P to the critical level (≥10 mg P kg−1soil bicarbonate extractable P) required for healthy maize growth. To maintain soil available P at the critical level where 52 kg P ha−1and combined 52 kg P ha−1+ 4 tons lime ha−1were applied, it would be necessary to reapply the same P fertilizer rate after every one and two cropping seasons, respectively. The 4-year mean grain yield increments were 0.17, 0.34, 0.50, 0.58 and 1.17 tons ha−1due to 2, 4, 6 tons lime ha−1, 26 kg P and 52 kg P ha−1, respectively. Both agronomic P use and P fertilizer recovery efficiencies increased with increasing rates of lime and decreased with increasing rates of P fertilizer. Therefore, combined applications of both lime and P fertilizer are important for enhancing maize production on P-deficient acid soils in western Kenya.

EFFECT OF COMBINING ORGANIC RESIDUES WITH MINJINGU PHOSPHATE ROCK ON SORPTION AND AVAILABILITY OF PHOSPHORUS AND MAIZE PRODUCTION IN ACID SOILS OF WESTERN KENYA

2007 ◽  
Vol 43 (1) ◽  
pp. 51-66 ◽  
Author(s):  
M. N. KIFUKO ◽  
C. O. OTHIENO ◽  
J. R. OKALEBO ◽  
L. N. KIMENYE ◽  
K. W. NDUNG'U ◽  
...  
Keyword(s):  
Soil Ph ◽  
Phosphate Rock ◽  
Farmyard Manure ◽  
Combined Treatment ◽  
Chicken Manure ◽  
Available P ◽  
Organic Residues ◽  
Maize Production ◽  
Study Results ◽  
Minjingu Phosphate Rock

Experiments were conducted in both the greenhouse and the field on highly weathered (Orthic Ferralsol) soils to evaluate the effect of combining on-farm organic residues (chicken manure, farmyard manure, sugar bagasse) with Minjingu phosphate rock (MPR) on soil pH, extractable (available) and sorbed phosphorus (P), and to assess the cost benefit for maize production. The greenhouse study results indicated that, in the first eight weeks of incubation, soil pH increased linearly with increase in MPR rates and decreased thereafter. The available P also increased linearly. Chicken manure and sugar bagasse were most and least effective respectively in reducing P sorption, while there was a significant negative relationship between P adsorption maxima and extractable P. The field experiment data showed that the available P values increased significantly above the control in all the treatments where MPR and organic materials were applied separately or combined. Treatment effects on Langmuir sorption maxima (Smax) in the field were variable. An increase in Smax with an increase in MPR rates was noted. However, there was a positive relationship between Smax and available P (r = 0.52 to 0.69), suggesting the diversity of factors affecting the complex nature of P dynamics under field conditions. MPR applied alone in the first season gave a significant residual positive effect on maize grain yield for two additional seasons. The economic analysis revealed that a single application of chicken manure (2 t ha−1) combined with MPR at 60 kg P ha−1 gave the highest incremental net benefit equivalent to US$ 657 ha−1 during the three maize cropping seasons.

scholarly journals Comparison of Chemical Properties and Application as Acid Soil Amendment of Pretreatment Center Slag and Other Slags

2001 ◽  
Vol 2 (2) ◽  
pp. 8-17
Author(s):  
Suwarno . ◽  
Itsuo Goto ◽  
Hiroshi Masujima
Keyword(s):  
Soil Ph ◽  
Soil Amendment ◽  
Converter Slag ◽  
Acid Soil ◽  
Chemical Properties ◽  
Available P ◽  
Liming Material ◽  
Exchangeable Ca ◽  
P Fertilizer ◽  
Bf Slag

Chemical properties of Pretreatment center slag (PTC-slag) were analyzed and compared to those of converter slag (C slag) and blast furnace slag (BF slag). PTC slag had a high EC value as well as citric acid soluble P and contained more Ca, Si, P, K, and Na but less Mg and Fe than C slag. Compared to BF slag, PTC slag contained more Fe, Ca, Mg, P, Mn, and Na but less Si, Al, and K. Although neutralizing value of PTC slag was lower than that of C slag, its ability to neutralize soilacidity was markedly higher. A pot experiment using Andisol from Tochigi Prefecture and komatsuna plant was carried outto evaluate PTC slag as liming material as well as P fertilizer. PTC slag, C slag, and dolomite were applied as liming materials and combined with super phosphate (SP). Addition of SP of 2.5 and 5.0% phosphate absorption coefficient (PAC) to PTC slag significantly improved the yield of komatsuna.This result, however, only apply for PTC slag adjusting soil pH to 6.5. Addit~ono f the same dosage of SP to PTC slag adjusting soil pH to 7.5 did not give significant effect. On the other hand, addition of SP of 2.5 and 5.0% PAC to C slag or dolomite significantly improved the yield for both C slag ordolomite adjusting. the soil pH to 6.5 and 7.5. Results of the experiment also indicated that P'TC slag and C slag significantly increased soil pH; exchangeable Ca, and Mg and improved available P, B, and Mn in Andisol. The magnitudes ofthese effects of the two slags, however, were difference. As compared to C slag and dolomite, PTC slag increased lower exchangeable Mg but higher available P. These results suggest that for acid soil amendment, PTC slag was better than dolomite and C slag due to the fact that this material supplymore P and B. Application of PTC slag as acid soil amendment will reduce the demand of P fertilizer, and even in high dosage can meet the P demand of komatsuna plant.

scholarly journals Dinamika P Tersedia, pH, C-Organik dan Serapan P Nilam (Pogostemon cablin Benth.) pada Berbagai Aras Bahan Organik dan Fosfat di Ultisols

2017 ◽  
Vol 14 (3) ◽  
Author(s):  
Any Kusumastuti
Keyword(s):  
Soil Ph ◽  
Block Design ◽  
P Uptake ◽  
Available P ◽  
Organic C ◽  
Randomized Block Design ◽  
Pogostemon Cablin ◽  
Soil Available P ◽  
Two Factors ◽  
The Media

The experiment was conducted at field experiment of Lampung State Polytechnic from June up to November 2012, using complete randomized block design with factorial pattern, which consists of two factors, and three replications. The first factor is organic matter (POME) dosage, consists of three dosages (without POME, 25% POME with 75% soil, and 50% POME with 50% soil). The second factor is dosage of SP-36 Fertilizer (without SP-36, 1.8 g, 3.6 g, and 5.4 g SP-36 per polybag (plant) respectively. The study aims was to determine (1) The dynamics of soil available P, (2) The effect of the best POME dosage for pH, C-organic and P uptake, (3) The effect of the best SP-36 dosage for pH, C-organic and P uptake, (4) The interaction between dosages of POME and SP-36 on pH, C-organic and P uptake of plant. The observation consists of (a) Soil available P, (b) pH and C-organic (c) and P uptake of plant. The data was analysis with variance analysis, furthermore, if the result is significance, was continued with LSD test, but soil available P dynamics was presented in graphic form. The result showed that (a) Applications of POME and SP-36 increase the soil available P, (b) The media with 25% POME and 50% POME were gave the better result on pH, C-organic and P uptake by plant, (c) SP-36 fertilizer fertilizer at various doses has not been any impact on soil pH, organic-C and P uptake of plants (d) There is no interaction between POME and SP-36 fertilizer on soil pH, organic C and P uptake of plants Keywords : P Dynamics, P Uptake of Patchouli, Pogostemon cablin, ultisols

scholarly journals Changes in Soil Available Phosphorus, Leaf Phosphorus Content and Yield of Sword Bean (Canavalia ensiformis (L.) DC.) by Application of SP-36 and Phosphate Rock on Acid Upland Soil of East Lampung

2016 ◽  
Vol 20 (1) ◽  
pp. 29
Author(s):  
Achmad Arivin Rivaie
Keyword(s):  
Soil Ph ◽  
Phosphate Rock ◽  
Phosphorus Content ◽  
Available P ◽  
Available Phosphorus ◽  
Upland Soil ◽  
Canavalia Ensiformis ◽  
Soil Available Phosphorus ◽  
P Fertilizer ◽  
Total P

A glasshouse trial was performed to determine changes in phosphorus (P) nutrition and the yield of sword bean (Canavalia ensiformis (L.) DC.) following the application of different rates and types of P fertilizer in an acid upland soil of East Lampung. Two different types of P fertilizer, namely SP-36 (total P = 36%) and Phosphate Rock (PR) (total P = 24.3%, particle size distribution = 75% <0.25 mm, 85% < 0.50 mm, 90% < 1.00 mm) were used in the trial. For the treatment, each P fertilizer type consisted of four rates (0, 50, 100 and 150 mg P2O5 kg-1 soil) that were arranged in a Completely Randomized Design with four replications. The results showed that the application of P fertilizers had significant effects on soil pH, soil plant-available P, the potential-P (HCl 25%), leaf N and P concentrations, the yield of sword bean. Increased rates of both forms of P fertilizer increased the soil pH values. As the soil used had low pH and very high exchangeable Al, hence, this result is most probably related to the addition of Ca2+ to the soil solution that resulted from the P fertiliser applied (liming effect), either from SP-36 (monocalcium phosphate) or PR (flour apatite). There was no difference in soil available P concentration due to the different in P fertilizer types, indicating that 4 months after the fertilizer application, the relatively insoluble Phosphate Rock had the same P solubility with SP-36. Increased rates of both forms of P fertilizer increased the sword bean yield. For the application of 0 kg P2O5 ha-1, although sword bean crops had pods, but, they did not give any seed. Whereas, at the addition of P fertilizer at the rate of 50, 100, and 150 kg P2O5 ha-1 for both P fertilizer types, the crops were able to give the seeds in the pods. [How to Cite: Achmad AR. 2015. Changes in Soil Available Phosphorus, Leaf Phosphorus Content and Yield of Sword Bean (Canavalia ensiformis (L.) DC.) by Application of SP-36 and Phosphate Rock on Acid Upland Soil of East Lampung. J Trop Soils 19: 29-36. Doi: 10.5400/jts.2015.20.1.29][Permalink/DOI: www.dx.doi.org/10.5400/jts.2015.20.1.29]

scholarly journals Quality Enhancement of Humid Tropical Soils after Application of Water Hyacinth (Eichornia crassipes) Compost

2017 ◽  
Author(s):  
Zainal Muktamar ◽  
Bajora Justisia ◽  
Nanik Setyowati
Keyword(s):  
Organic Matter ◽  
Soil Properties ◽  
Soil Ph ◽  
Particulate Organic Matter ◽  
Water Hyacinth ◽  
Sweet Corn ◽  
Available P ◽  
Exchangeable Al ◽  
Coefficient Corrélation ◽  
Compost Application

Compost application to soil leads to the improvement of its properties. However, nutrient content and enhancing capacity of compost are highly dependent on the original source and additive. The purpose of the experiment was to investigate selected soil quality indicators’ improvement and sweet corn growth following application of water hyacinth compost. Greenhouse experiment was carried out using Completely Randomized Design with 2 factors. First factor consisted of soils from humid tropics, i.e. Andepts, Udepts, and Udults and second factor comprised of water hyacinth compost rates, i.e. 0, 5, 10, 15, 20, and 25 Mg ha-1. Treatment combinations were replicated 3 times. Compost was incorporated in soil a week before planting of sweet corn. After reaching maximum sweet corn growth, soil sample was collected, air-dried, grinded and passed through 0.5 mm screen, and analyzed for selected soil properties, except microbial biomass carbon (MBC) and particulate organic matter carbon (POMC) which were analyzed using fresh soil samples. The experiment pointed out that application of water hyacinth compost on Udepts exhibited the highest total soil organic carbon (TSOC), MBC, soil pH and available P (Bray I), followed by those in Andeps and Udults. Particulate organic matter carbon (PMOC), however, was highest in Andepts as compared to other soils. Higher rates of compost application contributed higher increase in TSOC, MBC, soil pH, available P, and exchangeable K. Udults had more pronounced increase in soil pH and decline of exchangeable Al than other soils. Pearson correlation analysis showed that the most distinct correlation among soil properties was observed between exchangeable Al and soil pH, followed by TSOC and MBC with coefficient correlation of -0.91 and 0.85, respectively. Correlation between soil properties and sweet corn growth exhibited that the most prominent correlation was shown between available P and shoot dry weigh of sweet corn with coefficient correlation of 0.92. This indicates that soil available P has significant contribution on sweet corn growth.

scholarly journals PENINGKATAN EFISIENSI PEMUPUKAN FOSFOR PADA ULTISOL DENGAN MENGGUNAKAN ABU TERBANG BATUBARA

2020 ◽  
Vol 8 (1) ◽  
pp. 189-202
Author(s):  
F Fahrunsyah ◽  
M Mulyadi ◽  
Agus Sarjono ◽  
Surya Darma
Keyword(s):  
Growth Yield ◽  
Dry Weight ◽  
P Uptake ◽  
Absorption Efficiency ◽  
Available P ◽  
Exchangeable Al ◽  
P Fertilizer ◽  
Total Plant ◽  
Four Levels ◽  
Total P

Ultisol is one type of soil that has a very wide distribution in Indonesia, but the use of this soil faces many obstacles. The main problem in ultisol utilization is the low availability of phosphorus (P) and the low absorption efficiency. Coal fly ash (CFA) is a material that can overcome these problems. The objective of this study was to examine the effect of Application CFA on several soil chemical properties (pH, exchangeable Al, exchangeable Ca and available P), plant growth, yield, and absorption efficiency of P fertilizer. This study used a completely randomized factorial design consisting of two factors. The first factor was CFA that consisted of three levels of treatment, namely: A0 = 0 t ha-1 or without CFA, A1 = 40 t CFA ha-1, A2 = 80 t CFA ha-1. The second factor was P fertilizer that consisted of four levels of treatment, namely: P0 = 0 kg ha-1, P1 = 30 kg P ha-1, P2 = 60 kg P ha-1 and P3 = 90 kg P ha-1. The results of the study showed that the application of 80 t CFA ha-1 increased the pH by 13.41%, reduced exchangeable Al by 59.53% and increased exchangeable by Ca 192.66% compared to control. The combination 80 t CFA ha-1 and 90 kg P ha-1 increased available P by 986.79% compared to control. The application of 80 t CFA ha-1 resulted in the highest total plant dry weight and total P uptake. The treatment resulted in total plant dry weight of 172.96 g and total P uptake of 187.62 mg plant-1, increased 62.39% and 100.21% respectively compared to the control. The application of 90 kg P fertilizer ha-1 resulted in the highest total dry weight of maize, and total P uptake, namely 167.49 g and 174.39 mg plant-1, respectively, which means that the total plant dry weight increased by 51.00% and the total uptake P increased 69.79% compared to control. The highest seed dry weight was obtained in the combination of 80 t CFA ha-1 and 90 kg P ha-1, namely 39.33 g, an increase of 715.53% compared to the control. The combination of 40 t CFA ha-1 and 30 kg P ha-1 resulted in the highest absorption efficiency of P fertilizer, namely 30.43%. This means that in this treatment, maize can absorb 30.43% of the applied P fertilizer.

scholarly journals Micro-Dosing of Lime, Phosphorus and Nitrogen Fertilizers Effect on Maize Performance on an Acid Soil in Kenya

2015 ◽  
Vol 4 (2) ◽  
pp. 21 ◽  
Author(s):  
P. O. Kisinyo ◽  
P. A. Opala ◽  
V. Palapala ◽  
S. O. Gudu ◽  
C. O. Othieno ◽  
...  
Keyword(s):  
Grain Yield ◽  
Smallholder Farmers ◽  
Acid Soil ◽  
Acid Soils ◽  
N Fertilizer ◽  
Nitrogen Fertilizers ◽  
Maize Production ◽  
P Fertilizer ◽  
Fertilizer Recovery ◽  
Experimental Treatments

<p>High cost of inorganic fertilizers and lime has precluded their use by smallholder farmers to remedy the problem of soil acidity and infertility in Kenya. To address the problem, we tested a precision technique referred to as micro-dosing, which involves application of small, affordable quantities of inorganic inputs on an acid soil in Busia County, Kenya. Experimental treatments were N-fertilizer (0 and 37.5 kg N ha<sup>-1</sup>), P-fertilizer (0 and 13 kg P ha<sup>-1</sup>) and lime (0, 0.77 and 1.55 tons lime ha<sup>-1</sup>). 37.5 kg N and 13 kg P ha<sup>-1 </sup>are 50% of the recommended fertilizer rates for maize production in Kenya while 0.77 and 1.55 tons lime ha<sup>-1</sup> are 25 and 50% of the actual requirement. Soil chemical changes, maize grain yield and nutrient recovery were determined. Lime and P-fertilizer significantly affected only the top-soil pH, Ca, Mg and available P, while the effects of N-fertilizer were evident on both top- and sub-soil N likely due to its faster mobility than P and lime. Grain P-fertilizer recovery efficiencies were 14 and 16-27% due to 13 kg P and 13 kg P + 0.77-1.55 tons lime ha<sup>-1</sup>, respectively. N-fertilizer recovery efficiencies were 37 and 42-45% due to 37.5 kg N and 37.5 kg N + 0.77-1.55 tons lime ha<sup>-1</sup>, respectively. Fertilizers applied to supply 37.5 kg N, 13 kg P and 0.77-1.55 tons lime ha<sup>-1 </sup>increased grain yield above the control by 134, 39 and 12-22%, respectively, therefore micro-dosing of these inputs can increase maize production on Kenyan acid soils.</p>

scholarly journals Column Study of Nitrate Downward Movement and Selected Soil Chemical Properties’ Changes in Mine Spoiled Soil as Influenced by Liquid Organic Fertilizer

2017 ◽  
Author(s):  
Zainal Muktamar ◽  
Sari Hasibuan ◽  
Dotti Suryati ◽  
Nanik Setyowati
Keyword(s):  
Soil Sample ◽  
Soil Ph ◽  
Organic Fertilizer ◽  
Soil Column ◽  
Chemical Properties ◽  
Soil Chemical Properties ◽  
Available P ◽  
Downward Movement ◽  
Exchangeable K ◽  
Exchangeable Al

Open pit coal mining is common practice to extract coal from lithosphere. This system, however, will bring about soil degradation. Organic fertilization is an alternative to recover fertility of the degraded soil. The objectives of the experiment were to determine nitrate downward movement and change of selected chemical properties in the soil column and to compare the growth of lamtoro (Leucaena leucocephala) as affected by local based liquid organic fertilizer. Column experiment was conducted using mine spoiled soil from Taba Penanjung Sub-District, Central of Bengkulu District, Bengkulu, Indonesia located at approximately 364.5 m above sea level. The experimental design was Completely Randomized Design with 3 treatments consisting of control, 75 and 150 ppm of local based liquid organic fertilizer (LOF). The treatment was replicated 3 times. Soil column was prepared using PVC pipe with diameter of 12.5 cm and length of 40 cm. Soil sample was put into the column and compacted by knocking the base of the column until the soil height achieved 35 cm. Lamtoro was raised in the column for 11 weeks. At the end of experiment, lamtoro shoot was cut and the PVC column was cleaved horizontally and soil was pushed out from the column. Soil sample was, then, sliced into 6 fractions, representing depth of 0-5, 5-10, 10-15, 15-20, 20-25, and &gt; 25 cm. Fresh soil sample from each depth was extracted by distillated water and analyzed for NO3- N. Remaining of soil samples was air-dried for 72 hours, grinded with 0.5 mm screen, and analyzed for available P, exchangeable K, soil pH and exchangeable Al. The experiment indicated that local based liquid fertilizer significantly increased soil NO3-N, available P, exchangeable K, soil pH and reduced exchangeable Al. Higher rates of LOF caused increase in selected soil chemical properties but exchangeable Al. However, NO3-N was potential to move downward to deeper depth of the soil profile. Change of exchangeable Al, soil pH and exchangeable K was observed until 20-25 m depth of soil profile, but change of available P was detected only to 10-15 cm depth. Better soil chemical properties were followed by enhancement of lamtoro growth.

scholarly journals Influence of SP-36 and Phosphate Rock on Changes in Soil Available P, Leaf P Content, and Growth of Physic Nut (Jatropha curcas L.) in an Ultisol

2015 ◽  
Vol 19 (1) ◽  
pp. 9
Author(s):  
Achmad Arivin Rivaie
Keyword(s):  
Jatropha Curcas ◽  
Phosphate Rock ◽  
Fertilizer Application ◽  
Available P ◽  
Physic Nut ◽  
Jatropha Curcas L ◽  
P Content ◽  
Soil Available P ◽  
P Fertilizer ◽  
Leaf P

A study was carried out to determine the effects of rates and types of P fertilizer (SP-36 and Phosphate Rock) on the growth of physic nut (Jatropha curcas L.), leaf P content, and soil available P in an Ultisol in a glasshouse. The treatments consisted of four rates of P (0, 50, 100 and 150 mg P2O5 kg-1 soil) given in two different types of P fertilizer, namely SP-36 (total P2O5 = 36%) and Phosphate Rock (total P2O5 = 28%, particle size distribution = 75%<0.25 mm, 85%<0.50 mm, 90%<1.00 mm). Treatments were arranged in a Completely Randomized Design with three replications. The results showed that at the rates of 50 and 100 kg P2O5 ha-1, there was no difference in soil available P due to the application of SP-36 and Phosphate Rock, indicating that both types of P fertilizer had the same dissolution values after 8 months of P fertilizer application. At the rate of 50 kg P2O5 ha-1, the application of SP-36 and Phosphate Rock gave the same leaf P content. This could indicate that up to the first 8 months, the addition of the cheaper Phosphate Rock and the SP-36 to the soil had similar effectiveness. The response of tree biomass to P fertilization followed a quadratic pattern, in which for the application of Phosphate Rock, the P optimum rate was achieved at the rate which was lower than that for the application of SP-36. This suggests that the application of Phosphate Rock to physic nut trees was more efficient and effective compared to the application of SP-36.Keywords: Leaf P, phosphate Rock, physic nut (Jatropha curcas L.), soil available P, [How to Cite: Achmad AR. 2014. Influence of SP-36 and Phosphate Rock on Changes in Soil Available P, Leaf P Content, and Growth of Physic Nut (Jatropha curcas L.) in an Ultisol. J Trop Soils 19: 9-15. Doi: 10.5400/jts.2014.19.1.9]   

Build-up in soil available P and yield response of spring wheat to seed-placed P in a 24-year study in the Brown Soil zone

1993 ◽  
Vol 73 (2) ◽  
pp. 173-181 ◽  
Author(s):  
R. P. Zentner ◽  
C. A. Campbell ◽  
F. Selles
Keyword(s):  
Spring Wheat ◽  
Available P ◽  
Yield Response ◽  
Soil P ◽  
Olsen P ◽  
Leaf Stage ◽  
Extractable P ◽  
Soil Available P ◽  
P Fertilizer ◽  
Yield Responses

Producers in western Canada have applied phosphorus (P) fertilizer to annual crops for many years. This has increased soil available P and gradually decreased the expected yield response to P fertilization, but yield responses to small amounts of P placed with the seed are still reported regardless of soil available P levels. Controlled growth chamber studies suggest that the P responses should be most apparent during cool, wet springs. This 24-yr field study compared the yields of two fallow–spring wheat–spring wheat (F–W–W) systems, one fertilized with N and P each crop year, and the other fertilized with only N. The study, which was part of a long-term crop rotation experiment, was conducted on an Orthic Brown Chernozemic loam at Swift Current, Saskatchewan. Bicarbonate-extractable P (Olsen P) in the 0- to 15-cm depth in spring of the treatment receiving no P remained relatively constant (about 19 kg ha−1) throughout the study, while P fertilizer application at 6.5 kg ha−1 yr−1 increased extractable soil P by about 0.9 kg ha−1 yr−1. However, this increase in available P has not reduced yield responses to seed-placed P over the years. Regression analysis showed that yield response to P on fallow soil was positively related to temperature between emergence and the three-leaf stage and to precipitation at dough stage, but negatively related to precipitation near seeding time. For wheat grown on stubble, response to P was negatively related to temperature between 10 and 16 June (i.e., about the three- to four-leaf stage) and positively to precipitation received at anthesis stage. We concluded that, although available P in prairie soils has probably increased in recent years, producers can still expect to receive a 10% yield increase when small amounts of P are applied with the seed.Key words: Crop rotations, bicarbonate-extractable P, Olsen P, temperature effects, effect of precipitation

Sign in / Sign up

Export Citation Format

Share Document