Effect of Fertigation of Water-Soluble Fertilizers on Growth, Yield of Cowpea and Nutrients Availability in Soil under Rice-cowpea Cropping Sequence

Abstract

A investigation was carried out to study the Growth and yield of cowpea and primary nutrients availability in soil as influenced by fertigation of water-soluble fertilizers under rice-cowpea cropping sequence. Hybrid rice was tested under aerobic condition during Kharif 2015-16 and 2016-17 with 16 treatments replicated thrice in randomized block design.  The results indicated that, the treatment, 100% RDF through water soluble fertilizer at 8 DI was recorded significantly higher growth and yield determinants, higher seed yield (12.94 q ha-1) and haulm yield (26.17 q ha-1) of cowpea. Significant higher organic carbon (0.57 %) was recorded with the application 100% STCR dose with WSF through fertigation at 8 DI and higher available N (146.38 kg N ha-1 ), P2O5 (122.67 kg P2O5 ha-1 ) and K2O (130.17 kg K2O ha-1 ) content in soil recorded 100% water soluble fertilizers (WSF) applied at 4 DI. However, exchangeable calcium [3.51 cmol (p+) kg-1], magnesium [2.55 cmol (p+) kg-1], available sulphur [12.50 ppm] in soil were recorded with 100% conventional fertilizers applied plots through PoP. Significantly higher DTPA extractable Fe (18.45 mg kg-1) noticed with 100% STCR of WSF at 8 DI. However, significantly higher DTPA extractable Zn (1.44 mg kg-1) and Cu (0.57 mg kg-1) was recorded with the application of 100% RDF with WSF at 4 DI. Significantly higher DTPA extractable Mn (22.78 mg kg-1) noticed with 100% STCR of WSF at 4 DI.