SPAD Chlorophyll meter based nitrogen management strategy in direct seeded rice

To identify the SPAD chlorophyll meter based nitrogen management strategy in wet direct seeded rice, a field experiment was conducted at Agriculture Research Farm, Bihar Agricultural University, Sabour, Bhagalpur, Bihar, India during Kharif 2018. The experiment was conducted in split plot design which consisted of three rice cultivars as main plot treatments: Sabour Ardhjal, Shushk Samrat & Shabhagi Dhan and four N management practices as sub-plot treatments: No N (control), Fixed time N management (FTNM), Real time N management (RTNM) and Adjustable dose of N management (ADNM). Results revealed that among the cultivars, the maximum grain yield was obtained in Shushk Samrat (3956 kg/ha) which was statistically at par with Shabhagi Dhan (3752 kg/ha) whereas lowest grain yield was obtained in Sabour Ardhjal (3213 kg/ha). Among the N management practices, highest grain yield (4177 kg/ha) was recorded in ADNM which was at par with grain yield of FTNM (4134 kg/ha). Maximum gross (Rs. 79,957 ha-1) and net (Rs. 48,681 ha-1), B: C ratio (1.56) were obtained in ADNM. So, higher yields as well as sustainability of ecosystems can be achieved by practicing ADNM in direct seeded rice.