Plant- and microbial-based mechanisms to improve the agronomic effectiveness of phosphate rock: a review

Abstract

Defi ciency in plant-available phosphorus is considered to be a major limiting factor to food production in many agricultural soils. Mineral resources are necessary to restore soil phosphorus content. In regions where conventional fertilizers are not used due to cost limitations or to mitigate adverse environmental effects, local sources of phosphate rock are being increasingly recognized for potential use as alternative phosphorus fertilizers. The main obstacle associated with using directly applied ground phosphate rock is that the phosphate released is often unable to supply suffi cient plant-available phosphorus for crop uptake. Plantand microbial-based mechanisms are low-cost, appropriate technologies to enhance the solubilization and increase the agronomic effectiveness of phosphate rock. Common mechanisms of phosphate rock dissolution including proton and organic acid production will be reviewed for both plants and microorganisms. This review will also address possibilities for future research directions and applications to agriculture, as well as highlight ongoing research at the University of Guelph, Guelph, Canada.

Selection and evaluation of phosphate-solubilizing bacteria from grapevine rhizospheres for use as biofertilizers

“…A large portion of the total P in the soil is insoluble and unavailable for plant uptake. A deficiency in soluble P in many agricultural soils is one of the major factors hampering crop production worldwide (Arcand & Schneider, 2006;Yang et al, 2012). 2 night, long sunshine duration, and low rainfall, Northwest China has developed into a premium table-and wine-grape production area.…”

Arbuscular mycorrhizal fungus influence maize root growth and architecture in rock phosphate amended tropical soil

“…Therefore, frequent application of inorganic P (Pi) in the form of synthetic fertilizers becomes obligatory in crop production systems. But, the use of inorganic synthetic fertilizers on a regular basis is not only expensive but also environmentally undesirable (Arcand & Schneider 2006). Therefore, the current tendency is either to avoid or trim down the use of synthetic fertilizers and to increase the use of natural materials like rock phosphate (RP) in crop production (Arcand & Schneider 2006).…”

Phosphate solubilizing fungi isolated and characterized from Teff rhizosphere soil collected from North Showa zone, Ethiopia

“…The principal mechanism for many soil fungi and bacteria can solubilize inorganic phosphate into soluble form through the process of acidification, chelation, exchange reactions and production of organic acids (Han, 2006). Acid phosphatases play a major role in the mineralization of organic phosphorus in soil phosphate solubilization effect is mainly through the reaction between organic acids excreted from organic matters with phosphate binders such as Al, Fe, and Ca, or Mg to form stable organic chelates to free the bound phosphate ion (Arcand and Schneider, 2006;Gupta et al, 2012). Phosphorus deficiency is the most important problem of Ethiopian soil and more than 70 to 75% of highland soils are characterized by phosphorus deficiency (Beyene, 1982).…”