Solubilization of CaHPO4 and AlPO4 by Aspergillus niger in culture media with different carbon and nitrogen sources

Abstract

The solubilization of inorganic phosphates by microorganisms supplies phosphates for plant nutrition and increases their growth. The solubilization of CaHPO4 (Ca-P) and AlPO4 (Al-P) by Aspergillus niger using several carbon and nitrogen sources was studied. Solubilization of Ca-P was enhanced when the carbon sources were mannitol, maltose, galactose and glucose (in that order). Galactose, sucrose and maltose were the carbon sources that enhanced the solubilization of Al-P. More extensive growth, acid production, and decrease in pH were obtained in the Al-P medium than in the Ca-P medium, however, the quantity of solubilized phosphate was 12% less. Phosphate solubilization was related to acid production, pH drop and fungal growth in the culture medium. The results of a study carried out under abiotic conditions showed that organic acids solubilize more Ca-P than Al-P. Evaluating the effect of the nitrogen source, the solubilization of Ca-P or Al-P decreased in the following order: glycine > NH4Cl > NaNO3 and NH4NO3 > urea > (NH4)2SO4, respectively. Ammoniacal nitrogen (NH4 + -N) sources were the most effective in the production of acids and in lowering of the pH.

Plant Growth Promoting Efficiency of Phosphate Solubilizing Chryseobacterium sp. PSR 10 with Different Doses of N and P Fertilizers on Lentil (Lens culinaris var. PL-5) Growth and Yield

“…The role of microorganisms in solubilizing inorganic phosphates in soil and making them available to plants is well known (Bhattacharya and Jain, 2000). These microorganisms are called phosphate solubilizers and they convert insoluble phosphates to soluble phosphates by acidification, chelation, an ion-exchange reaction and production of low molecular mass organic acids (Barroso et al, 2006). Phosphate deficiency in soil can severely limit plant growth productivity of legumes, where both the plants and their symbiotic bacteria are affected and this may have a deleterious effect on nodule formation, development and function (Alikhani et al, 2006).…”

Evaluation of Phosphate Solubilizing Potential of Three Burkholderia Species Isolated from Green House Soils

“…This may be probably due to the adaptive nature of the enzyme that is responsible for solubilizing Ca 3 (PO 4 ) 2 (Banik and Dey, 1982). However, a few reports have indicated the other soil microorganisms to solubilize hardly soluble Fe or Al phosphates (Barroso et al, 2006;Antoun, 2002). Penicillum rugulosum was more efficient for solubilizing AlPO 4 and FePO 4 than hydroxyapatite (Reyes et al, 1999).…”

Impacto de herbicidas na biomassa microbiana e nos microrganismos solubilizadores de ortofosfato do solo rizosférico de cana-de-açúcar

“…Esses efeitos podem ser atribuídos à maior exsudação radicular da cultura como resposta aos efeitos fisiológicos provocados pelo herbicida (Shaw & Burns, 2004), o que possibilita maior eficiência dos microrganismos na solubilização de fosfato inorgânico. Essa eficiência é influenciada pela qualidade do carbono orgânico disponibilizado para os microrganismos (Barroso et al, 2006). O ametryn isolado ou em mistura com trifloxysulfuron-sodium reduziu os valores de solubilização.…”