Studies on the effect of organic and inorganic fertilizers on yield of coconut orchard in coastal ecosystem of Maharashtra State

The field experiment on impact of integrated nutrient management and organics including biomass recycling in coconut based cropping system was initiated on a 30 years old healthy D x T coconut plantation at Regional Coconut Research Station, Bhatye, Ratnagiri (M.S.) during the years 2013–14 to 2017–18. The experiment consisted of four treatments viz. T₁: 75% of recommended NPK +25% of N through organic recycling with vermi-compost, T₂: 50% of RDF+ 50% of N through organic recycling with vermi-compost + vermiwash application +bio-fertilizer application +in situ green manuring, T₃: 100% of N through organic recycling with vermi-compost +vermiwash application +biofertilizer application +in situ green manuring and green leaf manuring (glyricidia leaves) +composted coir pith, husk incorporation and mulching with coconut leaves and T₄: control: mono-crop of coconut with recommended NPK and organic manure were imposed. The component crops were nutmeg, cinnamon, banana and pineapple. Annual leaf production did not significantly differ among the treatments, however, integrated treatments resulted in higher number of leaves (30.46 Nos.). Five years pooled data on nut yield indicated that application of organic manures in combination with inorganic fertilizer either in 50% of RDF+50% of N through organic recycling with vermi-compost +vermiwash application +bio-fertilizer application +in situ green manuring (141.28 nuts/palm/year) or 75% of recommended NPK +25% of N through organic recycling with vermi-compost (126.33 nuts/palm/year) resulted the higher nut yield. There was improvement in the nutrient status of coconut leaves with integrated nutrient management practices compared to inorganic or organic manure alone application. The highest benefit: cost ratio (3.03) was recorded in T₂ followed by T₁ (2.81) as compared to the other treatments.