Water resources are becoming more limited worldwide and there is an urgent need to explore efficient irrigation technologies. The present paper investigates the feasibility of partial rootzone drying (PRD) for 'Pacific RoseTM' apple grown in a humid climate. The treatments were commercial irrigation (CI) as control and PRD. Only one side of tree row was irrigated in the PRD treatment with the other side left to dry to a volumetric soil water content of 0.18 to 0.22 m3 m-3 before being irrigated subsequently. In general, diurnal leaf water potential was the same for CI and PRD treatments. Stomatal conductance and photosynthetic rate appeared unaffected. Yield, mean fresh weight of fruit, trunk cross-sectional area (TCSA), yield efficiency (yield/TCSA), and shoot growth were the same between CI and PRD. Water use efficiency was improved in PRD trees. Fruit quality at harvest, in terms of internal ethylene concentration, starch pattern index, flesh firmness, total soluble solids concentration, and fruit skin background colour, was the same between CI and PRD. Dry matter concentration of fruit was lower in PRD fruit than in CI fruit. In summary, PRD did not adversely affect yield and fruit quality and improved water use efficiency by 120%, saving 0.14 mega litres of water per hectare.

carbon dioxide, colour, crop quality, crop yield, ethylene,ethylene production, firmness, irrigation, leaf conductance, leaf waterpotential, net assimilation rate, photosynthesis, plant water relations,stomata, water use efficiency, apples, Malus domestica, Malus, Rosaceae,Rosales, dicotyledons, angiosperms, Spermatophyta, plants, eukaryotes,carbon assimilation, carbon dioxide fixation, color, NAR, watering,Horticultural Crops (FF003) (New March 2000), Plant Water Relations(FF062), Soil Water Management (Irrigation and Drainage) (JJ800)(Revised June 2002) [formerly Soil Water Management], Composition andQuality of Non-food/Non-feed Plant Products (SS230)

• Journal Article

• Crop Water Use
• Irrigation Management