Nutrient use efficiency of rice genotypes under iron-toxic lowland soil influenced by high potassic fertilizer and foliar application of kinetin

Abstract

Improving global rice yield productivity under low-input conditions is the main challenge, especially in iron-toxic lowland acid soils. With India's irregular rainfall patterns and continual environmental anomalies, particularly in Odisha, the identification of climate-smart management practices that can withstand iron toxicity is critical. In this context, an experiment was conducted to develop effective nutrient use efficiency and nutrient management practices under iron-toxic lowland rice in lateritic acid soils of Central Farm, Odisha University of Agriculture & Technology, Odisha, with high-level use of potassic fertilizer along with the foliar application of Kinetin and five genotypes suitably fitted in a split-plot design. The results showed that the mean average performance of the genotypes was significantly increased at K120 and K100 levels along with Kinetin. At K levels of K100+Kn, the nutrient use efficiency was highest for nitrogen (68.60) and phosphorus (137.20). As regards potassium use efficiency in terms of AKR (100.81%), K40+Kn had the highest value of KGPE (935.72). The mean performance of the genotype in terms of total nutrient uptake in response to iron toxicity to different doses of K application showed a significant gradual increase with increasing K levels from K0-Kn to K120+Kn, and Hiranmayee had the highest total K uptake of 121.83 kg/ha. Total K uptake at K100+Kn was much higher than other doses, including control. These results suggest that high doses of potassium and foliar spray of Kinetin can alleviate the deleterious effects of iron toxicity in rice plants by enhancing physiological growth and nutrient uptake.