Mobilization of soil inorganic phosphorus and stimulation of crop phosphorus uptake and growth induced by Ceriporia lacerata HG2011

Abstract

The high-quality phosphorus (P) rocks on Earth may be depleted within the next fifty years. Hence, it is important to search for microbes that are effective in mobilizing soil legacy P. Therefore, a novel fungal strain (Ceriporia lacerata HG2011) was isolated and identified based on morphology and molecular biology. Then, liquid culture, soil incubation and field experiments were conducted to investigate the influence of this fungus on P mobilization and crop growth and P uptake in an eggplant-sweet sorghum rotation system. In the liquid culture experiment, P dissolved from Ca3(PO4)2 by fungal proton efflux accounted at least for 86.35% of the total dissolved P and the remainder was released by organic acids. As C. lacerata HG2011 grew on the soil surface, water-soluble P and Olsen P increased as the soil pH decreased. Fungal inoculation increased soil water-soluble P by 13.79–28.85 % and Olsen P by 4.12–17.82% compared to the uninoculated treatment. Compared to the use of chemical fertilizers alone, the field application of fungal inoculant in combination with chemical fertilizers at the time of eggplant transplantation increased crop P uptake by 10.03–29.48%, eggplant fruit yield by 6.83–16.07% and sweet sorghum shoot biomass by 12.59–18.42%. Olsen P and enzyme activities, including those of phosphatase, protease, urease and cellulase, were also significantly increased, probably indicating the stimulation of organic mineralization, releasing available P. To our knowledge, this is the first work providing information on soil P mobilization by C. lacerata, and on the potential use of this fungus as a biofertilizer in sustainable agriculture.