Controlled Environment Agriculture in Semi-arid North-West India

Abstract

Harsh agro-climatic conditions in the arid north-west India, such as the Kachchh region permit only sparse agriculture with limited choices, low yields and high risk of crop failure. Excessive groundwater withdrawal combined with inadequate recharge is making irrigation expensive and in the long run unsustainable. Controlled environment agriculture can' be a better and more sustainable way to make profitable horticulture possible in these areas. The outcome of one such initiative in which a special growing facility termed 'Arid Area Greenhouse' (AAG) was designed to grow vegetables in Kachchh region is discussed. AAG was developed keeping in view specific climatic and economic conditions - scarcity of water, hot winds, high levels of radiation, high temperatures, expensive and erratic power supply and only a low-end market nearby for fresh produce. Design goals of AAG ~ere to create an environment favorable enough for plants to produce an economic yield, to make cropping possible also beyond the monsoons, to employ such methods of environmental control that economize water and electricity usage and to produce vegetables to be sold competitively in the local market. AAG consists of a greenhouse coupled to earth-tube-heatexchanger (ETHE) in closed-loop and with additional provision for shading, natural ventilation and mist nozzles. It has been under investigation for over five years. It permits cropping over ten inonths Ouly-April), long enough to raise two crops. In open-fields here usually only one (monsoon season) crop is successful. Tomatoes have been raised over several rounds. In a recent round hybrid tomato yield was 68 t ha-\ nearly two times that. of the best yields on commercial farms in Gujarat. Water used in irrigation was 316 mm, nearly half of that in open fields. AAG holds promise as a new way to improve land and water productivity and raise vegetables in hot semi-arid regions. Key words: Earth-tube-heat-exchanger, arid area greenhouse, arid area, tomato.