Crop yield response to water - Cra

Water Requirements and IrrigationManagement RecommendationOn a midsummer day, a Mediterranean kiwifruit orchard consumes ~ 60-70 m 3 of water perha, and seasonally, around 300-350 litre of water per kg of fruit are supplied (for a yield of35 tonne/ha). Because of its high water demand and the sensitivity to dry environments, kiwifruitgrown in areas of high evaporative demand must be irrigated by microsprinklers in order tomaximize the soil surface area that is wetted. Volumetric soil water content should remain closeto field capacity at all times (never reaching values below 30 percent of the root zone waterstorage capacity), hence the need for frequent irrigation applications. The recommended cropcoefficients for kiwi are reported in Table 1, and Figure 10 shows an example of the seasonalvariation of soil water content in a Hayward kiwifruit orchard (southern Italy 40°08’ N; 16°38’ E).Table 1Crop coefficients for a mature microjet irrigated kiwifruit (Hayward) orchard grown in theNorthern Hemisphere (N 40° 23’ E 16° 45’). (seasonal irrigation volume = 10 012 m 3 /ha).Note that the whole soil surface area was wetted and the soil was not tilled.Apr. May June July Aug. Sept. Oct.0.5 0.7 0.9 1.1 1.1 0.80 0.80In conclusion, because of the sensitivity of kiwifruit to water deficits, RDI is not feasible inthis species, and full water supply to meet the crop water requirements must be ensured forsustainable kiwifruit production.496crop yield response to water