Production of garlic (Allium sativum L.) under controlled deficit irrigation in a semi-arid climate

Controlled deficit irrigation (CDI) has been studied in a garlic crop cultivated in a semi-arid zone. Eight drip irrigation treatments were differentiated by the level of fulfilment of the water requirements. The effect of deficit irrigation at three crop stages (vegetative development, bulbification and ripening) has been studied. Bulb yield has proved to be influenced by the total value of irrigation water. The treatments with no deficit during the ripening stage have had the highest productions. The deficit imposed at the ripening stage affects mainly the quantity (yield) obtained and the deficit imposed at the bulbification and ripening stages affects both quantity and quality (size). The mathematical function that best fits the production obtained with the water volume received is a second-degree polinomial. Adequate production rates may be reached with no more than 460 mm of total water received (irrigation+effective rainfall).