PLANT NUTRITION IN RESPONSE TO DRIP VERSUS BASIN IRRIGATION IN YOUNG ‘NAGPUR’ MANDARIN ON INCEPTISOL

Abstract

Evaluation of drip irrigation treatments scheduled at 40, 60, 80, and 100% of alternate day cumulative pan evaporation (Ecp) against basin irrigation method was undertaken in 1-year-old ‘Nagpur’ mandarin (Citrus reticulata Blanco) trees budded on rough lemon [Citrus jambhiri (L)] rootstock on an alkaline Inceptisol soil type for three seasons during 2003–2005. Growth responses showed significantly (P ≤ 0.05) higher annual increase in tree height (0.44–0.50 m), scion girth (37–45 mm), and canopy volume (0.508–0.986 m3) under drip-irrigation except irrigation at 40% Ecp, compared to tree height (0.40 m), scion girth (36 mm), and canopy volume (0.463 m3) under basin irrigation. The highest magnitude of increase in different growth parameters was observed with drip irrigation at 80% Ecp, which produced the net water saving of 32% over basin irrigation method. Response on leaf nutrient composition under drip irrigation at 80% Ecp likewise produced the similar response, [2.27% nitrogen (N), 1.98% potassium (K), and 121.8 ppm iron (Fe)], significantly (P ≤ 0.05) higher than under basin irrigation (1.12% N, 1.04% K, and 98.3 ppm Fe), with other nutrients, e.g., phosphorus (P), manganese (Mn), copper (Cu), and zinc (Zn) remained unaffected.