Irrigation in the Avocado cultivation
Introduction
Nowadays, the Avocado is considered to be a fruit of high economic interest. Over the past few years, worldwide consumption of avocado has grown strongly.
Nutritionally rich in healthy fats, vitamins and minerals, the increased consumption of this fruit seems to be registered mainly in the younger age groups.
This increase in consumption has served as an engine for new plantations, and in this area, Portugal presents itself as a country with a high productive potential due to the excellent edapho-climatic conditions suitable for this type of culture, especially the Algarve region and Vicentine coast.
This crop is very sensitive to water balance in the soil, a spectrum of nutrients in the soil with special vulnerability to frost.
Trio of systems
The irrigation of avocados aims to fill the water needs of the crop so that it approaches its maximum productive potential.
Integrated in the irrigation system, fertigation will be especially important in the determination of fertilisers in irrigation water in an efficient and articulated way with pH and electrical conductivity probes.
The anti-frost system will serve as a defense for the plants in situations of frost formation. It is a sprinkler system over the treetops.
Irrigation
The avocados are irrigated by localised irrigation (drop by drop). Dripping irrigation makes it possible to provide water efficiently, creating favourable water conditions close to the roots with little loss through evaporation and infiltration. Normally two lines of drip tube are applied per culture line. The flow and compass of the emitters are dependent on the characteristics of the soil, cultural varieties and agronomic management. The most common are spacing between 30 cm and 75 cm, and the flow rate between 0.7 l / h and 2.2 l / h.
Fertigation
In the fertigation system, a set of dosers will aspirate fertilisers from the fertiliser reservoirs and inject into the pipeline. In this way it is possible to dose precise quantities of fertilisers to water at specific times in an efficient manner. The fertiliser injection can be coordinated with a set of pH and conductivity probes. The irrigation programmer monitors and corrects the parameters giving a command to inject more or less if necessary.
Anti-frost
The anti-frost system is parallel to the irrigation system. In order to defend effectively, sprinkling is used on the treetops to prevent the creation of ice crystals. This system should be activated automatically as soon as the temperatures fall below a certain value. The temperature will be monitored by temperature probes connected to the irrigation programmer. This sprinkler system should have the ability to defend the entire area affected by frost and for it to be effective it should allow an allocation close to 2mm / h.
Conclusion
Avocado is a crop with special sensitivity to water conditions in the soil, fertilisation and frost.
To maximize the productivity of the crop, an irrigation system that acts on these three aspects is necessary so that there are no limiting factors.
The correct sizing of the irrigation system is essential because it must effectively guarantee the satisfaction of the water needs of the crop, the controlled dosage of fertilisers and a defense of the plants against frost.
