J. Lichou, M. Jay, L. Gonsolin, M.L. Massacrier, G. Du Fretay
Thinning the fruit must be done to ensure marketable fruit of peaches [Prunus persica (L.) Batsch], but it represents one-third of the labor costs. A new chemical, Armothin®, from AKZO-NOBEL, fatty amine polymer surfactant, has been tested since 1991 in France. In 1995, Armothin® was sprayed at 2% and 3% concentration at 60% of full bloom on 'Springcrest' peach compared to control trees in randomized plots. Fruit set was reduced on 'Springcrest' by 44% and 57% with 2% and 3% respectively, compared to the 82% natural set of control trees. Corrective hand thinning was done on each tree to adjust the number of fruit to the orchard potential. Total yield was increased by 6% with 2% concentration and reduced by 6% with 3% concentration. First fruit were slightly larger and earlier on treated trees than on control. No phytotoxicity was noted in the trial. Other tests were carried out in orchards without replication but on a larger scale to record thinning time. A good effect was noted in most cases and thinning labor was reduced by 33% in two orchards. Armothin® can be considered as a promising bloom-thinner at 2% concentration rather than 3%, but its effectiveness can be influenced by weather condition and by cultivar sensitivity.
Lichou, J., Jay, M., Gonsolin, L., Massacrier, M.L. and Du Fretay, G. (1997). ARMOTHIN®: A NEW CHEMICAL AGENT EFFICIENT FOR PEACH BLOSSOM THINNING. Acta Hortic. 451, 683-692
DOI: 10.17660/ActaHortic.1997.451.82
hand thinning, bloom thinning, surfactant

Acta Horticulturae