Pruning intensity and fruit load influence vegetative and fruit growth in an early-maturing peach tree (cv. Alexandra)

Abstract

Introduction. The distribution of shoots and fruits in the tree is an important con- sideration to improve peach cropping. Therefore, the effects of intensity of pruning were inves- tigated for two years in trees with the same fruit load and, the following year, in trees with different fruit loads. Materials and methods. In an early-maturing peach orchard (cv. Alexandra), three pruning intensities were applied for three years: light, medium and severe. The first two years, the same fruit load was applied for the different pruning treatments; in the last year, three fruit loads per tree were tested: low, intermediate and high. Results and discussion. Increasing seve- rity of pruning stimulated average fruit weight and fruit diameter, limiting (2nd year) or not (3rd year) fruit yield. Severe pruning also tended to enhance young shoot growth on the shoot bearing fruit and on the scaffold branch. Fruit diameter improvement with severe pruning might be therefore explained by the increase in vegetative growth likely to enhance available assimilates for fruit growth. However, severe pruning could favor an alternation in flower setting, as observed in the 2nd year. Increasing fruit load stimulated fruit yield, but, with the highest fruit load, no significant fruit yield enhancement was detected compared with the intermediate fruit load. On the contrary, average fruit weight and fruit soluble solids always decreased with increasing fruit load. Conclusion. Intensity of pruning and fruit load must be well adapted to ensure an appro- priate peach production; excessive pruning and fruit load of an early-maturing peach cultivar should be avoided in order not to limit fruit yield and quality, respectively. France / Prunus persica / pruning / growth / production / fruit / quality