Availability and leaching of nutrients after biofilm biofertilizer applications into a Red Yellow Podsolic soil

Abstract

Nutrient leaching in RYP soils lowers the fertilizer use efficiency in plantation agriculture of Sri Lanka. The study was conducted to determine nutrient leaching and their availability in a rubber (Hevea brasiliensis Mull Arg.) growing RYP soil supplied with biofilm biofertilizers (BFBF). Microorganisms isolated from rubber roots were formulated as BFBF under in-vitro conditions, and applied with or without 50% and 100% recommended chemical fertilizers into rubber seedlings growing in RYP soils packed in PVC columns. Combine use of inorganic fertilizer with BFBF reduced leaching loss of soil organic carbon throughout the experimental period. The application of BFBF had a marginal influence on leaching losses of K but it significantly reduced Mg losses. The leaching loss of N was not affected in the first two months, but from three months onward a significant reduction was observed with combine use of full recommended inorganic fertilizer with BFBF (100%F+BFBF) compare to inorganic fertilizer alone (100%F). Available nutrients, organic carbon and cations exchange capacity (CEC) in these two treatments were also comparable. Reduced leaching losses of some nutrients in the combine use of inorganic fertilizer with BFBF treatments (50%F+BFBF &100%F+BFBF) were not reflected in the nutrient status of the top soil layer (0-5 cm) but high plant dry matter accumulation was observed in BFBF treated plants. There is a possibility to reduce leaching loss of some nutrients and induce dry matter accumulation of rubber plants by BFBF application into RYP (Hapludults) soils.

Nutrients release from powder phonolite mediated by bioweathering actions

“…Soils with low CEC present high potential of K losses; reducing by this reason, the agronomic efficiency of fertilizers used (Hettiarachchi et al 2014). Thus, the application of silicate powder rocks directly in tropical soil can promove potential increase of the soil CEC (Anda et al 2009).…”

Microbial Consortia for Sustaining Productivity of Non-legume Crops: Prospects and Challenges

“…The FBB formed by bacterial colonization on biotic fungal surfaces can impart an enhanced metabolic activity in the biofilm compared to monoculture [51,82], and perhaps also compared to multispecies bacterial or fungal biofilms on abiotic surfaces [14,71,72]. But, under natural condition in soil, the success in formation of such biofilm is very less as it requires sufficient numbers of micro-organisms at adherence site and diazotrophs to meet the nitrogen requirement of biofilmed organisms [30,32].…”

“…Due to secretion of EPS, biofilm can hold nutrients efficiently and prevent nutrients loss. Nitrate leaching in rubber plantation was reduced by * 19% due to application of biofilm biofertilizers along with recommended dose of fertilizers [30]. Stimulation effect of biofilm on chlorophyll content of Anabaena torulosa (cyanobacteria) was observed [60], when it formed biofilm with Bacillus subtilis (bacteria).…”