Bio-efficacy of eco-friendly plant nutrient BioPhos on growth and yield of egg plant and onion* ABSTRACT R.V.S.K.Reddy*, Principal Scientist (Horti), Vegetable Research Station, ARI, Rajendra Nagar, Hyderabad - 500 030, Andhra Pradesh, INDIA, reddyrvsk23@rediffmail.com, N Sreerama Reddy, Ex Dean Agriculture, ANGR Agricultural University, Andhra Pradesh, Venkatesham. K , net2venky@gmail.com, nsreddy@prathista.com, Prathista Industries Limited,India  Objective of this research was to test the efficacy of BioPhos on productivity of eggplant (Solanum melongena) and onion (Allium cepa). Field experiments were conducted to study the effect of BioPhos granules and BioPhos liquid of Prathista Industries, Andhra Pradesh, India on growth and yield of egg plant. Among different treatments, recommended farmers practice excluding P2O5+ basal application of BioPhos @ 50 kg/ ha + 2 sprays of BioPhos liquid @ 2 ml / l of water at two critical stages (pre flowering and flowering) of crop development significantly increased plant spread, number of fruits per plant and yield over other treatments with application of P2O5 fertilizer. In terms of efficacy 1 kg of BioPhos granules was equivalent to about 2 kg of Single Super Phosphate (SSP) to supplement the required P, thus can be a good alternative to inorganic phosphate fertilizers. Cost Benefit Ratio (1:5) of BioPhos granules + 2 sprays of BioPhos liquid at two critical stages of crop growth and development was greater compared to inorganic control (1:4). Second study evaluated the effect of BioPhos granules @ 50 and 62.5 kg / ha as basal application in two split doses at 20 and 45 days after planting and 2 sprays of BioPhos liquid @ 3 ml / l at 25 and 45 days after planting on growth and yield of onion during summer and post rainy season. Among different treatments, 50% recommended dose of DAP + two foliar application of BioPhos liquid @ 3 ml / l was found significantly superior with regard to average bulb weight, yield per hectare, and greater cost benefit ratio, over other treatments with P2O5 (SSP, TSP and BioPhos granules). Overall, BioPhos as foliar spray was most effective when applied with other phosphatic fertilizers at half of the recommended dose.