Improvement of inceptisol’s biological properties under soil phosphorus manipulation by indigenous cellulolytic fungi-enriched organic fertilizers

Organic fertilizer quality affects its effectiveness as a soil amendment. The incubation study aimed to evaluate the effect of indigenous cellulolytic fungi (CF), Penicillium sp. isolate SR18, as an enrichment agent of organic fertilizers (OF) on soil available phosphorus and its correlation with the soil biology of Inceptisol. Seven treatments and three replications were arranged in a randomized block design. The treatments consisted of control, 5 g kg⁻¹ compost, 10 g kg⁻¹ compost, 5 g kg⁻¹ cow manure, 10 g kg⁻¹ cow manure, 5 g kg⁻¹ vermicompost, and 10 g kg⁻¹ vermicompost. This study observed available phosphorus, total microbes, phosphate solubilizer, and respiration. The results showed that indigenous CF-enriched OF (compost, cow manure, and vermicompost) as much as 5 g and 10 g kg^-1 improved soil av. P, total microbes, phosphate-solubilizers, and respiration both at 30 and 60 days after incubation (DAI). Application of higher doses of indigenous CF-enriched OF increased the available phosphorus, phosphate solubilizer, and respiration at 30 and 60 DAI (compost); available P at 30 DAI, total microbes, and respiration at 30 and 60 DAI (cow manure); available P at 30 DAI, total microbes at 60 DAI, phosphate solubilizer microbes at 60 DAI, and respiration at 30 and 60 DAI (vermicompost). The vermicompost enriched by cellulolytic fungi was superior to compost and cow manure in recovering soil available phosphorus and biological properties. There was a significantly positive correlation between available phosphorus with total microbes and phosphate solubilizer at 30 and 60 DAI and respiration at 30 DAI. This study highlighted that CF-enriched OF effectively recovers soil quality.