USING L-PEACH FOR DYNAMIC SIMULATION OF SOURCE-SINK BEHAVIOR OF PEACH TREES: EFFECTS OF DATE OF THINNING ON FRUIT GROWTH

G. Lopez, C. Smith, R. Favreau, T. DeJong
The goal of the L-PEACH, a functional-structural plant model, is to simulate tree architectural growth and carbohydrate source-sink relationships and transport in peach trees. Although the original model provided a basic prototype for how to integrate tree architectural growth and carbon economy, the simulation of crop yield responses to commercial practices was not previously addressed. The goal of this project was to test the ability of a new version of L-PEACH to simulate the effects of date of fruit thinning on fruit growth. To accomplish this objective interactions among fruit set, natural fruit abscission, date of fruit thinning, location of fruit in the tree architecture and source sink relationships were modelled. We simulated tree architectural development and dry mass growth of a peach tree until the beginning of the fourth growing season. This simulation output was saved and then additional simulations were restarted from the same point using different fruit thinning practices. The tree was either not thinned or thinned on four different dates; full bloom and 30, 60 and 90 days after bloom. Fruit thinning was established by using an automatic fruit thinning program in which the spacing between fruits was defined as four metamers (~11 cm) on individual shoots. There was a substantial benefit from reducing time between bloom and fruit thinning on seasonal patterns of mean individual fruit dry mass and final fruit mass distributions. This was because peach fruits were unable to recover potential growth lost early in the season. Therefore, as has been demonstrated in commercial orchards, L-PEACH simulations substantiated that to optimize fruit size and yield, fruit thinning should be carried out early in the season.
Lopez, G., Smith, C., Favreau, R. and DeJong, T. (2008). USING L-PEACH FOR DYNAMIC SIMULATION OF SOURCE-SINK BEHAVIOR OF PEACH TREES: EFFECTS OF DATE OF THINNING ON FRUIT GROWTH. Acta Hortic. 803, 209-216
DOI: 10.17660/ActaHortic.2008.803.27
https://doi.org/10.17660/ActaHortic.2008.803.27
functional structural plant modelling, fruit growth simulation, L-systems, source-sink relationships, tree modelling
English

Acta Horticulturae