Effect of Conjoint application of phosphorus and Nano DAP on growth and yield of Black gram (Vigna mungo L.)

Abstract

A field experiment entitled “Effect of Conjoint application of phosphorus and Nano DAP on growth and yield of Black gram (Vigna mungo L.)”was conducted during Kharif, 2024 at Instructional Farm, School of Agricultural Sciences, Dabok, Udaipur, Rajasthan to find out the effect of nano DAP on growth and yield of black gram, to explore whether application of nano DAP can fulfill the recommended dose of phosphorus and to work out an economically viable treatment. The experiment consisted of 8 treatments including viz.T1 (control), T2 (100% RDP), T3 (50% RDP), T4 (75% RDP), T5 (50% RDP + nano DAP 4ml l-1 one spray), T6 (50% RDP + nano DAP 4ml l-1 two sprays) T7 (75% RDP + nano DAP 4ml l-1 one spray) and T8 (75% RDP + nano DAP 4ml l-1 two sprays) which
were evaluated under randomized block design with 3 replications. Black gram variety PU 31 was used as test crop. The results revealed that maximum values of growth attributes viz., dry matter accumulation at 30 DAS was recorded with T7 (75% RDP + nano DAP 4ml l-1 one spray) and T8 (75% RDP + nano DAP 4ml l-1 two sprays) but at 60 DAS and at harvest it was recorded with T8 (75% RDP + nano DAP 4ml l-1 two sprays) and T7 (75% RDP + nano DAP 4ml l-1 one spray), while maximum values of CGR between 30-60 DAS was recorded with T2 (100% RDP) and between 60 DAS to harvest it was recorded highest with T7 (75% RDP + nano DAP 4ml l-1
one spray). Treatment T8 (75% RDP + nano DAP 4 ml l-1 two sprays) recorded significantly higher grain (588 kg ha-1 ), haulm (1625 kg ha-1 ) and biological (2213 kg ha-1 ) over control and T4 (75 % RDP) but at par with T2 (100% RDP). However, T2 (100% RDP) fetched highest net return (₹31048 ha-1 ) and highest B-C ratio (0.89), which significantly superior over T8 (75% RDP + nano DAP 4 ml l-1 two spray).