Validation of sensor based nitrogen management in maize in Godavari zone of Andhra Pradesh

Abstract

Precision nitrogen management techniques in maize viz., Green seeker optical sensor, Site specific nutrient management (SSNM) through Soil􀀐test crop response (STCR) or Nutrient expert have the potential to increase nitrogen fertilizer use efficiency, productivity, profitability and to reduce losses under changing climate. A Field study was conducted at Agricultural Research Station, Peddapuram, East Godavari Dist. during kharif, 2018 on sandy loam soils to evaluate the effect of sensor-based nitrogen application on growth, yield and economics of Maize. The experiment was conducted in RBD with three replications. Treatments consisted of T1-Control, T2-RDF (1/3+1/3+/1/3 N splitting at basal, knee high and tasseling), T3-STCR (1/3+1/3+/1/3 N splitting at basal, knee high and tasseling), T4-Nutrient expert (1/3+1/3+/1/3 N splitting at basal, knee high and tasseling), T5 -33% basal N + Green Seeker based N at knee high & tasseling stage , T6-60% basal N + Green Seeker based N at knee high stage , T7- 70% basal N + Green Seeker based N at knee high , T8-60% basal N + Green Seeker based N at tasseling stage , T9- 70% basal N + Green Seeker based N at tasseling stage , T10- 30% Basal N + 30% at 25 DAS + Green Seeker based N at tasseling stage, T11-35% Basal N + 35% at 25 DAS + Green Seeker based N at tasseling stage, T12 -N rich strip (300:60:40) (1/3+1/3+/1/3 N splitting at basal, knee high and tasseling). Experimental results revealed that the application of 35% Basal N + 35% at 25 DAS + Green Seeker based N at tasseling stage recorded significantly higher grain yield (6114 kg/ha) which was at par with 30% Basal N + 30% at 25 DAS + Green Seeker based N at tasseling stage (5975 kg/ha) and RDF (5647 kg/ha). Similarly, highest net returns and B:C ratio (Rs.47505 /ha & 2.25 respectively) was recorded with 35% Basal N + 35% at 25 DAS + Green Seeker based N at tasseling stage which was at par with 30% Basal N + 30% at 25 DAS + Green Seeker based N at tasseling stage (Rs. 45952/ha & 2.22) and RDF (Rs.40566/ha and 2.05) with nitrogen saving of 33 kg/ha. Based on the present study, It can be inferred that though yield was at par with RDF green seeker based nitrogen application could be a better option in terms of profitability and nitrogen saving in maize. Thus, In future precision nitrogen management using green seeker optical sensor can be successfully used for making site specific in season fertilizer nitrogen management decisions for maize in Godavari zone of Andhra Pradesh.