Optimization of tensiometer-based drip irrigation scheduling and its effect on growth, yield and water use efficiency in tomato (Solanum lycopersicum).

Abstract

Tensiometer is the most preferred soil moisture monitoring sensor for drip irrigation scheduling in vegetable crops because of its low cost, easy to use and accurate measurement of soil moisture tensions. In tomato, tensiometer-based drip irrigation scheduling along with mulching may reduce evaporation and increase water and nutrient use efficiency. In the present investigation, three irrigation schedulings, i.e. drip irrigation at - 40, - 60 and - 80 kPa, and three mulching treatments (black polythene, BP; paddy straw, PS; and no mulched control) were applied. Experimental findings revealed that scheduling drip irrigation when tensiometer reads at -40 kPa coupled with BP mulching registered the maximum leaf area (0.648 m2/plant), number of fruits (35.7/plant) and fruit yields (2.72 kg/plant or 891.68 q/ha). The maximum chlorophyll content index (41.8) was observed with -40 Kpa ? PS mulching, while maximum water use efficiency (355.31 kg/ha/mm water) with drip irrigation was at - 60 kPa ? BP mulch. The lowest weed growth (31.27 g dry matter/m2) was registered under BP mulching followed by PS mulch (111 g/m2) irrespective of irrigation scheduling.