Nitrogen management in irrigated wheat (Triticum aestivum) using optical sensor Green Seeker

A field experiment was conducted during the winter (rabi) season of 2013–14 at Hisar, to study the GreenSeeker optical sensor based N management vis-a-vis recommended N application in wheat [Triticum aestivum (L.) emend. Fiori & Paol]. Application of 25 + 50 kg N/ha at sowing and 25 days after sowing (DAS) and GreenSeeker guided N application at second and third irrigation i.e. 33 and 31 kg N/ha produced maximum grain yield (6.60 t/ha) and saved 11 kg N/ha. The same treatment recorded 8.4 to 15% and 11 to 27% higher agronomic efficiency and recovery efficiency, respectively as compared to recommended dose of N application. GreenSeeker guided N both at second and third irrigation stage, resulted into significantly improved yield and N-use efficiency. Single stage GreenSeeker guided N at second irrigation was better than third irrigation in terms of yield and N-use efficiency. Three split N application resulted in significantly higher nitrogen recovery efficiency (14.4%) than 2 split application.