Responses of mango trees to reduced irrigation regimes.
Pavel E. W., Villiers A. J. de
Author Affiliation: Department of Plant Production and Soil Science, University of Pretoria, Hatfield, Pretoria 0002, South Africa.
: 63-68
Abstract : Four-year-old 'Kent' mango (Mangifera indica) trees were subjected to 5 irrigation regimes consisting of the control (Co), a regulated deficit (RDI) and 2 progressively reduced irrigation (PRI-1, PRI-2) treatments as well as the farm control. The orchard, located in Hoedspruit, South Africa, was well suited for pulse irrigation because of its soil particle size distribution (81±7% sand, 5±5% silt, and 13±5% clay), high infiltration rates (289±52 mm h-1), and low water holding capacities (90±20 mm water/m soil). During 2000/01, frequent applications of irrigation water led to water savings in the range of 32-58% water in the 4 treatments compared to the farm control. Leaf photosynthetic rates were significantly reduced in PRI-2 in summer. In response to the first water withholding period before flowering (May/June 2000), stomatal conductance rates were significantly lower in the RDI treatment compared with the other treatments. Reduced irrigation treatments (PRI-1, PRI-2, RDI) significantly reduced the vegetative growth compared with the farm control. Yield was not significantly affected by the various irrigation treatments. However, differences in yield between treatments seemed to be mainly related to fruit number indicating that the reduced irrigation treatments might have affected rather growing conditions before flowering or during the early stages of fruit growth than later in the season.