Modeling mango fruit and vegetative growth.
Grossman Y. L., González A., Pavel E. W.
Author Affiliation: Department of Biology, Beloit College, 700 College St., Beloit, WI 53511, USA.
: 33-40
Abstract : A carbon budget model of mango (Mangifera indica) tree growth was used to examine factors that limit mango crop yield. The model was adapted from PEACH using field data from the Northern Territory, Australia (using cv. Kensington Pride) and Hoedspruit, South Africa (using cv. Kent). At both locations, instantaneous leaf level carbon assimilation rates varied seasonally, from lows of 3-6 µmol CO2 m-2 s-1 to high values of 10-11 µmol CO2 m-2 s-1. Crop growth occurred when photosynthetic rates were in the lower half of this range, except near the time of fruit harvest in South Africa. Simulated gross carbon assimilation increased through the season from low values in July-August to high values in February-April. Simulated carbon availability limited crop growth during a portion of the fruit growth period at both locations. Simulations of the effect of crop load on fruit growth examined the effect of increasing initial fruit set and final fruit number. For Kensington Pride mangoes in Australia, increasing final fruit number did not decrease final fruit size, but increasing both fruit set and final fruit number decreased final fruit size substantially. For Kent mangoes in South Africa, increasing final fruit number without and with increasing fruit set reduced final fruit size to similar extents. We conclude that efforts to increase fruit set may not increase the numbers of marketable-sized fruits because of carbon limitations on fruit growth.