ECONOMIC IMPACT OF IRRIGATION TECHNOLOGY ON VEGETABLE CROPS IN DEVELOPING COUNTRIES
The working hypothesis of this research project is that a high rentability can be achieved from the investments needed to establish a sounding irrigation technology at the field. This is of outstanding importance for developing countries in which irrigation water has only a minimal value per-se, and, as a result, irrigation methods used by the farmers are highly inefficient (less than 20% of the water applied is actually used by the crop), and many productive soils cannot be irrigated.
Permanent irrigation plots are operated in different locations in the Central Zone of Chile, on which a specified crop rotation is practised for a number of years. Several irrigation methods are tested, with different irrigation frequencies and water application depths.
The results obtained indicate that yields have increased more than 25% over check plots, on which irrigation is applied according to the farmers' tradition, when the only variable was irrigation technology. The cost to implement such technology is translated in benefits upon direct yield increases, and general crop management savings, being the investment on irrigation technology, a hightly profitable decision.
When improving irrigation technology in the field, a significant increase on consumptive use of water by the crop can be expected, but total water applied during the growing season is about half of the volume needed with traditional irrigation methods.
The increments on water use efficiencies obtained with improved irrigation technologies, indicate that a major effort should be devoted to implement it under field conditions, rather than on constructing new reservoirs or other hydraulic works.
For developing countries with a comparatively extended irrigation tradition, little sophistication on the improvement of irrigation technology is needed to get a significant economic impact on crop production.