Abstract

The study was conducted to optimize the use of water and nutrients by Japanese mint (Mentha arvensis L.) with three moisture regimes [I₁ drip irrigation at 100%, I₂ at 80% and I₃ at 60% pan evaporation (PE)] and three fertility levels (F₁ 100%, F₂ 75% and F₃ 50% recommended dose of NPK) with an extra (control) treatment having surface irrigation and soil application of fertilizer. The experiment was laid out in Factorial Randomized Block Design with three replications at the Experimental Farm of the Directorate of Water Management, Bhubaneswar India (20° 30' N lat., 87° 48' E long, 45 m above mean sea level) during winter (dry) seasons of 2005-2006 and 2006-2007. Drip irrigation increased the herbage and oil yield by 15.9 and 15.2%, respectively as compared to surface irrigation. It saved 29% water as compared to the latter (925 mm). Soil moisture regimes maintained at 100% PE significantly enhanced crop growth, herbage yield (34,798 kg ha^-1), essential oil yield (254 kg ha^-1) and N uptake (120 kg ha^-1) compared to 60% PE. Application of 100% recommended dose of fertilizer significantly produced maximum herbage (32,572 kg ha^-1) and oil yield (246 kg ha^-1). Combination of irrigation at 100% PE with 100% RD of fertilizer produced maximum quantity of oil (260 kg ha^-1) with improvement in its quality as compared to other levels tested.

Key words: Drip irrigation, fertilizer, Japanese mint, pan evaporation, recommended dose.