Exploratory Study on the Irrigation Regime in a Pitahaya (Hylocereus undatus) Plot

Abstract

The cultivation of pitahaya has expanded in recent years in many regions of the world, especially in Ecuador with predominance in its tropical regions. Although its production constitutes an important source of income, there are few publications related to its cultivation techniques and irrigation management in the country. This work constitutes an exploratory study conducted in Manabí, Ecuador in a 1.25 ha plot planted with red pitahaya. The average field capacity expressed as a percentage of dry soil was determined by the gravimetric method with a value of 42.96% pss (value equivalent to 45% of volumetric humidity measured with a DELTA-T HH2 probe at the same site). To know the water requirements of the crop irrigated by a microsprinkler system, irrigation programming was developed using the CROPWAT program. The average annual irrigation interval obtained was 3.7 days, with extreme values ​​of 9.3 days in February and 2.7 days in November. These results were compared with the spatial and temporal distribution of humidity in periods of 1 hour, 72 hours and seven days after irrigation. The humidity measured with the electromagnetic probe showed that surface humidity maintained values ​​lower than the critical depletion fraction of 30% up to 72 hours after irrigation. This result is similar to that provided by CROPWAT (3.7 days), which confirms the need to water the crop every four days on average depending on the season and rainfall contributions.