Abstract

                                Field experiments were conducted during 2015-16 and 2016-17 at New Area farm, Department of Forage Crops, Tamil Nadu Agricultural University, Coimbatore to optimize the water and nutrient requirement under drip fertigation in Bajra Napier hybrid grass CO (BN) 5. Experiment An experiment was laid out in Randomized Block Design with three replications. The treatments consisted of different irrigation levels and N fertigation levels viz., Paired Row Drip System (PRDS) (60/90 x 50 cm) + Drip at 100 % PE + N fertigation at 75 % Recommended Dose of Fertilizer (RDF) (T1), PRDS (60/90x50 cm) + Drip at 100 % PE + N fertigation at 100 % RDF (T2), PRDS (60/90 x 50 cm) + Drip at 100 % PE + N fertigation at 125 % RDF (T3), PRDS (60/90 x 50 cm) + Drip at 125 % PE + N fertigation at 75 % RDF (T4), PRDS (60/90 x 50 cm) + Drip at 125 % PE + N fertigation at 100 % RDF (T5), PRDS (60/90 x 50 cm) + Drip at 125 % PE + N fertigation at 125 % RDF (T6), Surface irrigation (5 cm depth) + soil application of N at 100 % RDF (Farmers’ practice) (T7).Drip irrigations were given based on pan evaporation (PE). The fertilizer dose followed was 150:50:40 kg NPK/ha as basal and 75 kg N /ha after each cut. Results showed that drip irrigation at 125 % PE + N fertigation at 125 % RDN recorded higher number of tillers per plant (29.8), plant height (246.3 cm), green fodder yield (378.7 t/ha/ yr), dry matter yield (104.5 t/ha/yr), gross return (Rs. 568097/- /ha/yr.) and net return (Rs. 4,17,180/- /ha/yr.). It was on par with drip irrigation at 125 % PE + N fertigation at 100 % RDN. Hence, drip irrigation at 125 % PE + N fertigation at 100 % RDN was found to be optimum for achieving the maximum growth yield and net return in Bajra Napier hybrid grass CO (BN) 5.

Key words : Bajra Napier hybrid grass CO (BN) 5, Drip fertigation, Green fodder yield..