Effects of the amount of water applied, method of irrigation, and rate of N-application, on herbage and oil yields, N-uptake, and water-use efficiency in patchouli [Pogostemon cablin (Blanco) Benth.] grown under semi-arid tropical conditions

Abstract

SummaryA field experiment was conducted during 2008 and 2009 at Bangalore, India, to study the effect of the amount of irrigation water applied (20, 25, or 30 mm per irrigation), the method of irrigation (i.e., flat-bed, or broad-bed and furrow) and nitrogen level (0, 50, or 100 kg N ha–1) on herbage and oil yields, nitrogen (N) uptake, and water-use efficiency of patchouli [Pogostemon cablin (Blanco) Benth.]. At the highest level of N (100 kg N ha–1), the broad-bed and furrow method was better suited for irrigating patchouli compared with the flat-bed method of irrigation. The highest herbage yield was achieved following the application of 100 kg N ha–1 and 30 mm water per irrigation. However, with 25 mm irrigation, the broad-bed and furrow method increased N uptake (45.7 kg ha–1) significantly compared with the flat-bed method of irrigation (36.7 kg ha–1). The broad-bed and furrow method of irrigation increased the water-use efficiency significantly compared with the flat-bed method of irrigation. The content and quality of patchouli oil were not influenced by the amount of irrigation water, the method of irrigation, or N-level.