ISHS Acta Horticulturae 80: Symposium on Growth Regulators in Fruit Production
EFFECTS OF TEMPERATURE, SHOOT-TIPPING, AND CARBARYL ON FRUIT SET OF APPLE TREES |
| Author: | J. Grauslund |
| Abstract:
Young apple trees grown in pots were exposed to different temperatures during one or two week periods between bloom and end of June drop. Trees were placed in three growth rooms in a greenhouse with the following temperature levels: 12–13, 16–17, and 19–21°C. Selected flowers were hand pollinated. Bee-hives were placed in the green-house to ensure good pollination of all flowers. Good initial fruit set was obtained. At harvest final fruit set and total number and weight of fruits were determined. Fruit drop was accelerated, final fruit set was lower and fruit size increased after a period with high temperatures. Shoot-tipping 2 weeks after full bloom increased fruit set, but could not eliminate the effect of high temperature on fruit drop. Spraying with carbaryl 2 weeks after full bloom decreased fruit set and increased fruit size. | |
Download Adobe Acrobat Reader (free software to read PDF files) | |
