Foliar nutrient management through Kappaphycus and Gracilaria saps in rice-potato-green gram crop sequence

A field experiment was conducted during 2010-11 and 2011-12 on sandy loam soil at Uttar Chandamari village of Nadia district of West Bengal (22° 57' N latitude, 88° 20' E longitude) to study the effects of seaweed saps on crop growth and yield vis-a-vis nutrient uptake by the crops under rice-potato-greengram sequence. The foliar application of seaweed extracts (namely Kappaphycus and Gracilaria) at different concentrations (0, 2.5, 5.0, 7.5, 10.0 and 15.0% v/v) significantly enhanced the growth, yield and nutrient uptake by the crops in sequence. The application of 15% Kappaphycus sap along with recommended dose of fertilizer (RDF) recorded the highest productivity in terms of rice equivalent yield (REY) with net monetary returns of Rs. 175608.60 ha yr and benefit: cost ratio of 2.06.