Vol. 11, Issue 4 (2022)

Author(s):
Ajmal KK, M Goverdhan, S Sridevi and K Suresh

Abstract:
Management practices needed to be developed for semi dry rice which is grown in both aerobic and anaerobic condition during their growth cycle. Low nutrient use efficacy is one of the most limiting factor for production of the rice. A field experiment was conducted at Agricultural Research Institute, PJTSAU, Rajendranagar during the kharif season of 2017 to study the SPAD meter reading, nutrient uptake and nitrogen use efficiency of semi dry rice under varied doses and time of application. The experiment was laid out in randomized block design with ten treatment and three replications. Application of 160 kg N ha^-1 25% each at sowing, 20 DAS, 40 DAS and 60 DAS recorded the highest SPAD meter reading, nutrient uptake and nitrogen use efficiency compared to the other treatments. However, this was found to be on par with the growth in the treatments having 160 and 140 kg N ha^-1applied at various splits and with application of 120 kg N ha^-1 N in 4 equal splits at sowing, 20, 40 and 60 DAS. The lowest observation was found to be with application with of nitrogen at 120 kg ha^-1 N in 3 splits with 12% at sowing, 44% at 40 DAS and 44% at 60 DAS (farmer’s practice). The study conclusory proved that application of the 120 kg N ha^-1 N in 4 equal splits at sowing, 20, 40 and 60 DAS enhanced the SPAD meter reading, nutrient uptake and nitrogen use efficiency in semi dry rice.