Phosphorus fractions in Andisol and Ultisol inoculated with Bacillus thuringiensis and phosphorus uptake by wheat

Abstract

Only a small portion of soil phosphorus (P) is available to plants on a short-term basis, and therefore, P taken up by crops in one growing season is small compared to total P (Pt) content of the soil. A group of soil microorganisms capable of transforming insoluble P into soluble and plant accessible forms. The objective of this study was to evaluate the changes in soil P-pools and P uptake by wheat crops as influenced by inoculation with Bacillus thuringiensis in two soils (Andisol and Ultisol), the experiment was conducted in pots under greenhouse conditions using a completely randomized design. Wheat plants were inoculated and re-inoculated at 20 and 46 days after sowing, respectively, with B. thuringiensis; and, plant sampling were performed after 46, 66 and 87 and soil at 87 days based on the Zadoks growth scale, and the soil was submitted by Hedley’s P fractions. The inoculation with B. thuringiensis affected significantly some P organic P (P_o) and inorganic P (P_i) fractions in both soils (Andisol and Ultisol), improved P uptake by wheat crop in (Ultisol) and decreased significantly in (Andisol). The positive effect was more consistent in Ultisol than in Andisol, this strain can be solubilized P fraction extracted with conc. HCl-P_o and HCl 1 mol.

Keywords:

• Andisol
• Bacillus thuringiensis
• phosphorus fractions
• Ultisol
• wheat

Conflicts of interest

The authors declare no conflict of interest.

Additional information

Funding

This research was supported by Department of Soils and Natural Resources/Faculty of Agronomy/Concepción University, and the first author grateful the Nelson Mandela scholarship of the International Cooperation Agency of Chile (AGCI), for the scholarship.