Desmond R. Layne*1, Zhengwang Jiang1 and James W. Rushing2, Department of Horticulture, Clemson University,
2Coastal Resarch and Education Center (REC), 2865 Savannah Hwy., Charleston, SC 29414.
Replicated trials were conducted in summers of 1998 and 1999 at two
commercial orchards (A and B) to determine the influence of a metalized,
high density polyethylene reflective film (SonocoRF, Sonoco Products Co.,
Hartsville, SC) and ReTain (Abbott Laboratories, Inc., N. Chicago, IL),
on fruit red skin color and maturity of 'Gala' apples. There were four
experimental treatments: i. Control; ii. Reflective Film (RF); iii.
ReTain; and iv. RF + ReTain. RF was laid 4 weeks before anticipated
first pick date by laying a 5' wide strip of plastic on either side of
the tree row in the middle. ReTain was applied 4 weeks before harvest at
the commercial rate in one orchard (A) and at 60% the commercial rate in
the other orchard (B). At harvest, two 50-fruit samples were picked
from each of four replicate blocks per treatment. All fruit were
sized and visually sorted for color (1=0-25%, 2=26-50%, 3=51-75%, and 4=76-100%
red surface, respectively). A 10-fruit subsample was selected following
color sorting and evaluated for puncture pressure, soluble solids concentration
(SSC) and starch hydrolysis. ReTain delayed maturity and reduced
preharvest drop of Gala's. Fruit from RF trees had a significantly
greater % red surface than fruit from trees not treated with RF.
Fruit from RF + ReTain were significantly redder and had higher SSC than
fruits from trees treated with ReTain alone. There were no differences
in size, puncture pressure or starch hydrolysis between RF and RF + ReTain.
RF appears to be a means to ensure greater redness in Gala's treated with
ReTain in South Carolina.
Citation: Layne*, D.R., Z. Jiang, and J.W. Rushing.
2000. The influence of reflective film and ReTain on red skin color
and maturity of 'Gala' apples in South Carolina. HortScience 35:495.
Presented at the 2000 Annual Conference of the American Society for Horticultural
Science in Orlando, FL.
Preferred Presentation Type: ORAL
Commodity Group: FRUITS/NUTS
Specialty Group: CROP PHYSIOLOGY