Compost amendment enhances the biological properties of Andosols and improves phosphorus utilization from added rock phosphate

Abstract

The aim of the present study was to investigate the relationship between the uptake of phosphorus (P) from rock phosphate (RP) by plants and the enhancement of the biological properties of the soil by compost amendments. In experiments conducted in Wagner's pots (200 cm 2 ), the enrichment of Andosols with RP at 0, 100, or 200 mg P kg )1 soil was combined with the addition of one of four types of compost at a rate equivalent to 13.3 mg P kg )1 soil or with no compost treatment, and the amended soils were used to grow African millet (Eleusine coracana Gaertn, cv. Yukijirushi) for 60 days. The composts added to the soil were based on poultry manure (PM), cattle manure (CM), sewage sludge (SS), or P-adjusted sawdust (PSD). In an incubation experiment, RP was added at 0 or 150 mg P kg )1 of soil in combination with each of the four types of compost at the same rate of application as in the pot experiment, or with no compost. The uptake of P from RP (RP-P) by plants was highest with PM, followed by CM and PSD, and then SS; it was four-to five-fold more with compost addition than no compost addition. Microbial biomass P was significantly higher when RP was added with PM or CM. RP-P uptake by plants showed a positive correlation (r = 0.72, P < 0.05) with the microbial biomass P in the soil. In the soil incubation, the population density of phosphate-solubilizing bacteria (PSB) was significantly higher in compost-amended soils than in the absence of compost treatment, and was highest with the addition of PM. The available P in soil showed a positive correlation (r = 0.70, P < 0.05) with the population density of PSB. These results show that the uptake of P from RP by plants is enhanced by amendment with compost, especially PM or CM compost, and is strongly related to the biological properties of the soil, such as the microbial biomass P and the population density of PSB.

Compost amendment enhances population and composition of phosphate solubilizing bacteria and improves phosphorus availability in granitic regosols

“…4b). This result is supported by the findings of previous study, which showed a similar relationship using Andosols (Wickramatilake et al 2010).…”

“…The strong positive correlation between RP utilization by plants and the microbial biomass P was shown by a previous study using Andosols (Wickramatilake et al 2010). The results of this study show that the microbial biomass P at day 15 has a strong positive correlation with available P at day 30 of soil incubation (r ¼ 0.71; p < 0.01) (Fig.…”

“…In addition, a number of fungal species solubilize P; these species generally belong to the genera Aspergillus or Penicillium (Reyes et al 1999;Vazquez et al 2000). The significant positive correlation between utilization of RP by plants and the population density of PSB enhanced by compost amendments in Andosols was shown by Wickramatilake et al (2010).…”

Potential Utilization of Local Phosphate Rocks to Enhance Rice Production in Sub-Saharan Africa

“…These can be expected to form complex cations of PRs, as well as lowering rhizosphere soil pH. Further, there are also P-solubilizing soil microbes 57 , such as bacteria, including Bacillus spp. and Pseudomonas spp., and fungi, including Actinnomycetes spp., Penicillium spp., and Aspergillus spp.…”

“…Wickramatilake et al (2010) showed that the P uptake from low-grade Chinese PR by African Millet (Eleusine coracana Gaertn) is enhanced by poultry and cattle manure compost and that it is strongly related to microbial biomass P and the population density of P-solubilizing bacteria 57 . Moreover, the addition of sulfur to PRs, which promotes the dissolution of PR due to the sulfuric acid that is produced by Thiobacillus spp.…”