Growth, Yield and Water Use Efficiency of Sweet Sorghum [Sorghum bicolor (L.) Moench] Affected by Drip Irrigation and Nitrogen Levels through Fertigation

An experiment entitled “Growth, yield and water use efficiency of sweet sorghum [Sorghum bicolor (L.) Moench] affected by drip irrigation and nitrogen levels through fertigation” was carried out on clayey and slightly alkaline soil during rabi season of 2019-20 and 2020-21 at the Instructional Farm, Department of Agronomy, College of Agriculture, Junagadh Agricultural University, Junagadh. The experiment was laid out in split plot design with four replications. There were nine treatment combinations. The main plot treatments viz; (I1) drip irrigation at 0.6 PEF, (I2) drip irrigation at 0.8 PEF and (I3) drip irrigation at 1.0 PEF; and sub plot consist of three nitrogen fertigation levels viz; (N1) 75% RDN through fertigation, (N2) 100% RDN through fertigation and (N3) 125% RDN through fertigation (RDF for sweet sorghum is 90-40-40 N, P2O5 and K2O kg ha-1). The results revealed that drip irrigation scheduling at 1.0 PEF enhance consumptive use of water and nitrogen use efficiency which ultimately resulted in higher grain and fodder yields of sweet sorghum. The results indicated that 125% RDN through fertigation significantly increased water use efficiency, which eventually recorded higher grain and fodder yields of sweet sorghum. Based on the results of two years experimentation, it can be concluded that for getting higher grain and fodder yields, sweet sorghum should be applied two common surface irrigation each of 50 mm depth followed by scheduling drip irrigation at 0.8 PEF (operating pressure: 1.2 kg cm-2 and lateral spacing: 120 cm) at alternate day and crop should be fertilized with 100% RDN through drip fertigation out of which, 50% RDN as basal and remaining 50% RDN in five equal splits at 10 days interval through fertigation started from 35 DAS.