Phosphorus activators contribute to legacy phosphorus availability in agricultural soils: A review

Abstract

Phosphorus (P) is one of the most limiting macronutrients for crop productivity and P deficiency is a common phenomenon in agricultural soils worldwide. Despite long-term application of phosphate fertilizers to increase crop yields, P availability is often low, due to the high affinity of phosphate for the soil solid phase. It has been suggested that the accumulated (surplus) P in agricultural soils is sufficient to sustain crop yields worldwide for about 100years. In this paper, we try to clear up the potential for making use of legacy P in soils for crop growth potentially alleviating the global P resource shortage. Specifically, we try to clear up the potential of soil "P activators" for releasing fixed P. P activators accelerate and strengthen process which transform P into bio-available forms via a range of chemical reactions and biological interactions. They include phosphate solubilizing microorganisms, phosphatase enzymes and enzyme activators, low molecular weight organic acids, humic acids, lignin, crop residues, biochar and zeolites. Although reported performance is variable, there is growing evidence that P activators can promote the release of phosphate from soil and, hence, have potential for mitigating the impending global P crisis. Further basic and applied research is required to better understand the mechanisms of interaction of P activators with natural soils and to maximize activator efficacy.

Phosphorus deficiency promotes the lateral root growth of Fraxinus mandshurica seedlings

“…Phosphorus deficiency is one of the greatest limitations in the development of agriculture and forestry ( Zhu et al., ). In this study, P deficiency significantly decreased the biomass dry weight, and shoot dry weight of F. mandshurica seedlings (Fig.…”

Dual‐mycorrhizal plants: their ecology and relevance

“…This is especially important for P, which occurs primarily as apatite (calcium phosphate) in young soils, and strongly complexed with iron and aluminium oxides or as secondary calcium phosphates in older or highly weathered soils (Walker & Syers, 1976). Roots and microbes, including mycorrhizal hyphae, LMWOAs (Griffiths et al, 1994;Rineau et al, 2008), which facilitate release of orthophosphate from phosphate minerals through complex and poorly understood mechanisms (Zhu et al, 2018). Although both EM and AM hyphae release LMWOAs (Plassard & Dell, 2010), Allen et al (1996) found oxalate crystals on only EM hyphae in southern California.…”

Impact of Phosphorus Fertilization on Tomato Growth and Arbuscular Mycorrhizal Fungal Communities

“…Soil P usually limits plant growth due to its poor mobility. Currently, overcoming P deficiency and increasing soil P availability is a necessary issue for achieving high crop productivity, highlighting the need to apply large amounts of inorganic P fertilizers in agricultural ecosystems [1][2][3][4]. Conversely, P has accumulated in agricultural soils due to the application of chemical fertilizers to mitigate the high P fixation capacity of acidic soils in Japan [2,5].…”