Author(s): Ramjeet Yadav, Manish Pandey, Tushar Kant Upadhyay, A Kohli, YK Singh, AK Jha and PK Yadav

Abstract: Rainfed rice productions under drought stress are serious limiting factors, the results in quantity of economic losses. It is becoming a more serious problem with respect to the global environment changes. The current and forecasted global foods requirements, it has become to enhancing the crop productions on the drought stress rainfed areas with the fundamentality. In order to achieve the production goal from rainfed lands there is a requirement of varieties of the rice with drought tolerance, and amendment for drought stress tolerant should be a high precursory theme of research in the next ensuing. A field experiment was undertaken during wet seasons of 2017 and 2018 to evaluate the response of soil applied Potassium and Nitrogen splitting in rice (Sahbhagi Dhan) under rainfed lowland conditions. The experimental was laid out on a sandy loam soil of Bihar Agricultural College farm, Sabour to derive inputs for rationalizing the use of Potassium (K) and Nitrogen (N) fertilizers by splitting and real time management respectively for making them more suitable for rainfed conditions. Nutrient and water management are important for diversifying and intensifying the rainfed rice based cropping systems. The greatest progress has been made during last two decades in our understanding of the mechanisms & strategy involved in adaptation and tolerance to rainfed rice productions under lowland conditions. The experiment involved three K splitting schemes viz., K₀ (No K application), K₄₀ (K applied as basal @ 40 kg K₂O per ha) and K₂₀₊₂₀ (K application as basal, and at panicle initiation stage each @ 20 kg K₂O per ha) in main plots, and five N splitting schemes in sub plots viz., N0 (No N application), N₅₀₊₅₀ (N application as basal and at active tillering, each @ 50 kg per ha) NSPAD (N application as basal each application @ 33.33 kg ha^-1 and top dressing as guided by SPAD meter with critical SPAD value of 38, N_GS (N application as basal @ 33.3 kg per ha and top dressing as guided by Green Seeker optical sensor) and N_33+33+33 (N application as basal, at active tillering and at panicle initiation, each @ 33.3 kg per ha.). The results revealed that the tolerance indexin N₅₀₊₅₀, NGS and N_33+33+33 was at par with each other, but that in NSPAD was significantly greater than that in N₅₀₊₅₀, NGS and N_33+33+33. The mean productivity in N₅₀₊₅₀, NGS and N_33+33+33 was at par with each other. The rice crop mean productivity in NSPAD was significantly greater than that in N₅₀₊₅₀, NGS and N_33+33+33. Across various N splitting schemes, the stress tolerance index was found to be significantly lower in N-control in comparison to other N-splitting schemes.

DOI: 10.33545/26174693.2024.v8.i3f.802