Tensiometer based drip irrigation scheduling for enhancing water productivity of capsicum (Capsicum annum L.) under polyhouse

The present study was undertaken to study the response of tensiometer based drip irrigation scheduling on water requirement, water productivity, biometric growth and yield parameters; and economics of Capsicum (Capsicum annum L.) under two different types of naturallyventilated polyhouses viz., Double span naturally ventilated polyhouse (DS NVPH) and walking tunnel type naturally ventilated (WT NVPH). The experiment was laid out in randomized block design with three levels of irrigation maintained at 20–30 kPa, 30–50 kPa, 50–70 kPa soil moisture tension with the help of tensiometers, installed between two plants on their root zone at the depth of 20 cm and two fertigation levels i.e. 75 and 100% of recommended doses of fertilizers and a control i.e. surface irrigation with 100% recommended dose of fertilizers. The maximum average water use efficiency Water productivity, were 98.27 kg/m³ and 87.05kg/m³ at 50–70 kPa soil moisture tension for capsicum in double span and walking tunnel type naturally ventilated polyhouses, respectively. The maximum yield was rerecorded in drip irrigation scheduled at 50–70 kPa soil moisture tension and 75% of recommended doses of fertilizers (13.14 kg/m²) and minimum in control (8.52 kg/m²) in DS NVPH. In WT NVPH the maximum yield was rerecorded in drip irrigation scheduled at 20–30 kPa soil moisture tension and 100% of recommended doses of fertilizers (13.81 kg/m²) and minimum in control (9.56 kg/m²). The water use efficiency in tensiometer based drip irrigation treatments increased 281% in DS NVPH and 248% in WT NVPH over control i.e. surface irrigation. The water productivity in tensiometer based drip irrigation was increased 274% in DS NVPH and 250% in WT NVPH over control i.e. surface irrigation. Production of coloured capsicum under both the polyhouse were economically feasible at selling price higher than Rs. 20/kg.