Influence of drip irrigation and fertigation levels on physiological characters and yield of aerobic rice (Oryza sativa L.)

Water shortage is becoming severe in many rice growing areas in the world. Conventional method of irrigation, which not only consumes huge water, but also causes severe water and nutrient losses under anaerobic condition. Introduction of aerobic rice, growing high yielding rice in non-puddled and non-flooded aerobic soil with the support of external inputs like supplementary irrigation, manures and fertilizers can reduced water use and increase rice production.

Study on different levels of drip irrigation and fertigation on physiological characters and yield of aerobic rice was conducted during summer 2022 and 2023 at research farm of wetland in Tamil Nadu Agricultural University, Coimbatore, Tamil Nadu. The experiment was laid out in randomized complete block design with thirteen treatments, replicated thrice.

The findings revealed that drip fertigation @ 100% PE up to 30 DAS+150% PE up to 60 DAS+200% PE up to 90 DAS with 125% RDF (25% through NF+75% through WSF) resulted significantly higher leaf area index (5.84 and 5.95), chlorophyll index (SPAD) (41.5 and 42.3) and grain yield (4315.9 and 4446.1 kg ha^-1) respectively than all other treatments during both summer 2022 and 2023. However, significantly lower leaf area index (2.70 and 2.91), chlorophyll content (31.9 and 32.2) and yield (2301.0 and 2364.8 kg ha^-1) observed with fertigation at 50% PE up to 30 DAS+100% PE up to 60 DAS+150% PE up to 90 DAS with 75% RDF (75% through NF+25% through WSF), respectively in summer 2022 and 2023.