Performance evaluation of summer irrigated green gram (Vigna radiata L.) by combined application of basal nitrogen and foliar fertilization of nano urea

A field experiment was conducted at wetland farm of Tamil Nadu Agricultural University, Coimbatore during the summer season, 2022 to study the influence of integrated application of basal nitrogen and foliar feeding of nano and conventional urea on growth, physiology, yield parameters, yield and quality attributes of irrigated green gram. The experiment was laid out in Factorial Randomized Block Design (FRBD) with two factors viz, different basal nitrogen dose (N) and foliar supplementation of various concentration of nano and conventional urea at flower initiation (FI) stage and 15 days thereafter (F). There were four levels under each factor namely, N1 - 100 % RDN (Recommended Dose of Nitrogen) (25 kg N ha-1), N2 - 80 % RDN (20 kg N ha-1), N3 - 60 % RDN (15 kg N ha-1) and N4 - Nitrogen free control under factor I. Likewise, F1 - Nano urea @ 2 ml litre-1 of water, F2 - Nano urea @ 3 ml litre-1 of water, F3 - Nano urea @ 4 ml litre-1 of water and F4 - 1 % conventional urea under factor II. The experimental outcomes revealed that the treatment combination of 100 % RDN + foliar spray of nano urea @ 4 ml litre-1 of water at FI stage and 15 days thereafter significantly recorded superior values of plant height, leaf area index, crop growth rate, relative growth rate, net assimilation rate, chlorophyll content, soluble protein content, nitrate reductase activity, fertility co-efficient, grain yield, protein content and protein yield. Nevertheless, it was on par with basal application of 80 % RDN + foliar nutrition of nano urea @ 4 ml litre-1 of water at FI stage and 15 days thereafter. Thus, adoption of 80 % RDN as basal dose integrated with foliar feeding of nano urea @ 4 ml litre-1 of water at FI stage and 15 days thereafter could be the viable integrated nitrogen management practice to enhance the performance of green gram under summer irrigated conditions.