IRRIGATION OF STRAWBERRIES BY THE USE OF DECISION SUPPORT SYSTEMS

The use of water for irrigation purposes is legally limited in the Netherlands.
To achieve efficiency in irrigation the use of tensiometers and a computerised version of an irrigation planner were tested in strawberries.
Drip irrigation was applied when critical tensiometer readings were reached.
In 1997 and 1998 values were 200 and 300 hPa.
In 1999 values were 100 and 200 hPa.
Opticrop BV in Vijfhuizen provided the irrigation planner used.
The irrigation planner calculates daily, the amount of water in the root zone of the plants by taking into account soil type, rainfall, irrigation, capillary water movement, percolation, root growth, evapotranspiration under different developmental stages and local weather circumstances.
The irrigation planner has to be actualised daily.
This is laborious.
The assumed growth pattern of the crop is not always achieved, leading to miscalculations in crop evaporation.
The irrigation planner calculates water content of the soil using a limited number of soil types.
However in agricultural practise soil types may differ from the pre-set soil type of the planner, leading to smaller or bigger miscalculations.
The use of tensiometers proved more satisfactory.
To obtain reliable readings at least 3 tensiometers are needed and these must be checked regularly.
Tensiometers need thorough maintenance.
It was shown that crop productivity increased at lower tensiometer values than assumed.
Growing strawberries at field capacity (100 hPa) led to an increase in yield of 1.0 t / ha compared to strawberries grown in a field irrigated at 200 hPa.
To use water efficiently and to avoid loss through percolation, frequent irrigation using small amounts of water is necessary.

IV International Strawberry Symposium

A. Evenhuis, J. Alblas

Fragaria x ananassa, water management, tensiometer, irrigation planner, suction rate

https://doi.org/10.17660/ActaHortic.2002.567.100