Ecology, Environment and Conservation Paper

EFFECT OF NANO UREA (LIQUID) ON YIELD AND FERTILIZER SAVING IN RICE UNDER ISLAND ECOSYSTEM

T. Subramani, A. Velmurugan, N. Bommayasamy, Manoj Kumar, Y. Ramakrishna and T.P. Swarnam

Abstract

In recent years, there is a growing compulsion to address the issue of stagnant input response and growing environment concerns. Thus a field experiment was conducted during 2021 at two farmer’s field viz., Guptapara (South Andaman) and Nimbudera (Middle Andaman) to study the effect of nano urea (liquid) on the growth, yield, economics and nutrient use efficiency of rice under island conditions. There were 6 treatments viz., N0PK, N100PK, N50PK + Nano Urea (0.2%), N75PK + Nano Urea (0.2%), N50PK + Nano Urea (0.4%) and N75 PK + Nano Urea (0.4%). Nano urea (liquid) was sprayed two times at 0.2 % and 0.4 % concentrations. The recommended dose of fertilizers was 90:60:60 NPK kg/ha. The paddy varieties viz., CIARI Dhan 2 (Medium duration) and ANR 40 (long duration) were used at Guptapara and Nimbudera, respectively. The results revealed that application of nano urea (liquid) spray with conventional fertilizer had significant impact on growth, yield attributes and yield of rice at both the farmer’s field. Further, nano spray (N75PK and 0.4 % Nano urea) contributes to additional yield of 16.6 and 12 % and additional monetary benefit of Rs. 12,598 and 8091 in Guptapara and Nimbubdera, respectively than only NPK addition through chemical fertilizers (100 % RDF). Further, there is little difference between nano spray at 0.2 % and 0.4% spray though higher concentration of (0.4%) nano spray gave 3.7 and 5.4 % higher yield and 9.0 and 9.2 % higher net return in Guptapara and Nimbubdera, respectively. Nano urea spray with N50 and N75 had significant effect on Partial factor productivity, Nitrogen use efficiency (NUE crop) and Agronomic efficiency. The increased efficiency of nano urea resulted in saving of mineral urea when compared to the chemical fertilizer application to the extent of 25 % at farmers’ field. At the same time increasing the concentration of Nano spray from 0.2 to 0.4% had no impact on the saving without increasing the N addition. Spraying of nano urea can increase crop yield by increasing the nutrient uptake by plants and its bioavailability in soil. Spraying of nano urea is proved to be beneficial for island ecosystem as it lead to saving of chemical fertilizer thereby reducing the accumulation of N in the environment.