C. Xiloyannis, P. Angelini, A. Galliano
The results obtained in trials applying two different volumes of water in relation to 'A-pan' evaporation and from investigations carried out in some kiwifruit orchards where drip irrigation was used empirically give rise to the following considerations:
  • In all orchards drip irrigation was badly planned, in that the number of drippers chosen, their positioning and their discharge rate bore little relation to the pedoclimatic characteristics and to the water needs of the plants.
  • Irrigation was started too late, when available water in the top 80 cm of soil had already dropped to 40%.
  • With drip irrigation we should begin to apply water when about 70% of available water (soil water potential - 0.02 MPa) is still intact in the layers of soil containing the majority of roots.
  • The volumes of water applied in the orchards irrigating empirically were lower than the effective evapotranspiration, so that plants rapidly exhausted the soil water reserves.
  • In order to calculate the appropriate volumes, it is essential to know at least weekly values of rainfall and 'A-pan' evaporation, and the correction coefficients to be applied to the latter during the irrigation season. The coefficient of 1.2 applied from June to October, in mature plants, gave the better results.
  • During the period of highest water consumption, irrigation should be daily or at most every two days since the limited volume of soil wet by the drippers can hold only enough water to satisfy the plants'needs for one or two days.
  • Finally, orchards should be irrigated for as long as effective evapotranspiration is not satisfied by rainfall.
Xiloyannis, C., Angelini, P. and Galliano, A. (1990). DRIP IRRIGATION OF KIWIFRUIT TREES.. Acta Hortic. 282, 217-226
DOI: 10.17660/ActaHortic.1990.282.28

Acta Horticulturae