MODEL BUILDING FOR PREDICTION OF ETHEPHON THINNING EFFECTS

In a series of sequenced experiments over the 5 growing seasons 1980–85, data has been collected on many factors affecting the efficacy of ethephon thinning of Golden Delicious.
These environmental, physical and tree factors include, time of application of thinner, spray dosage (concentration and volume), ambient temperature and blossom density.

Time of application and spray concentration were originally selected as the two factors suspected of contributing most to observed variation in spray thinning programmes, and experiments were conducted to quantify this effect as a response surface in terms of a three dimensional model.
The secondary factors: temperature, spray dosage and blossom density were examined in subsequent years, providing data for continual refinement of the earlier model.

Using a systems approach to research, these factors have been combined to produce mathematical models, predicting such yield variables as: number of fruit per 100 blossom clusters, number of fruit per cm² trunk area, mean fruit weight, and number of fruit greater or equal to 70 mm diameter.

V International Symposium on Growth Regulators in Fruit Production

T.B. Koen, K.M. Jones, M. Oakford

https://doi.org/10.17660/ActaHortic.1986.179.107