In 2003, the total equipped area for full or partial control irrigation was 226 600 ha, of which 195 500 ha used localized irrigation, 27 100 ha surface irrigation and only 4 000 ha sprinklers (Figure 3).
Full or partial control irrigation is by far the most widespread type of irrigation, covering 94% of the area (Table 4).
Partial wetting irrigation influences soil moisture distribution, which potentially changes soil nitrous oxide (N2O) emission.
Partial rootzone irrigation (PRI) means that part of the root system is exposed to drying soil while the remaining part is irrigated as in full irrigation.
Hybrids with a robust hydrotropic response showed growth and developmental patterns, under drought and partial lateral irrigation, that differed from weak hydrotropic responders.
These results demonstrate the benefit of intensive phenotyping of hydrotropism in primary roots since maize plants that display a robust hydrotropic response grew better under drought and partial lateral irrigation, indicating that a selection for robust hydrotropism might be a promising breeding strategy to improve drought avoidance in maize.
In 1993, the total area of land equipped for full or partial control irrigation was estimated at 3 128 079 ha.
In 1990, the total water managed area, all equipped for full or partial control irrigation, was estimated at 763 ha, which is about 7% of the agricultural land.
The major crops under full or partial control irrigation are melons, tomatoes, potatoes, pumpkins, marrow and cauliflower, with a total cropped area of 1 807 ha (average cropping intensity is 2.5).
Partial root-zone irrigation (PRI) is an irrigation technique to save irrigation water without much yield reduction.
