Reflective Particle Films Improve Apple Quality
Durham September 16, 2008
Spraying apple trees with films that contain microscopic mineral
particles may improve the color of the fruit and increase its weight.
That's according to Agricultural
Research Service (ARS) research leader
Michael Glenn, who is studying these sprayable films at the ARS
Fruit Research Station in Kearneysville, W.Va.
Glenn and entomologist
Puterka, formerly at Kearneysville and now at the ARS
Peanut and Other Field Crops Research Laboratory in Stillwater, Okla.,
conducted a multi-year study in which sprayable particle films were installed
strategically in an orchard of Empire apple trees. The particle film's
microscopic layer of mineral particles allows water and carbon dioxide to pass
through the film.
With some trees, an aluminized plastic film (ALF) was applied to the
grass strip between the apple rows. With other trees, a sprayable
particle-based reflective film (PF) was applied to the trees as well as the
grass between the tree rows. A third group of trees received no treatment.
The ALF consistently improved apple color, while the PF increased red
color in apples in two of the three years of the study. When PF was applied to
the grass between tree rows, the average fruit weight was increased in all
years of the study, compared to the untreated trees and those that received the
The mechanism responsible for the increased fruit weight with the PF
may be the altered light quality that is reflected onto the fruit. This
reflected light has enhanced far-red radiation that may have beneficial effects
on both fruit color and fruit weight. The particle film also reduced heat and
water stress in plants and improves production efficiency.
Based on these findings, new management techniques can be developed
that will improve apple quality in a cost-effective manner.
ARS is a scientific research agency of the
U.S. Department of