LAKE ALFRED, FLSuccessful mechanical harvesting of perennial fruit crops requires efficient, economical harvesting systems that do not reduce trees' production life or diminish fruit quality. Most of the world's citrus is now harvested manually, but the use of efficient and lower-cost mechanical harvesting techniques is expected to increase in the next few years, especially in the large citrus plantations in Florida and Brazil. The citrus industry is ramping up efforts to extend the harvest season past June, when the following year's crop becomes large enough to be susceptible to mechanical harvesting; discovering techniques that improve late-season harvesting will give growers better tools to minimize damaging impacts on the next year's fruit yield.
Researchers from the University of Florida's Citrus Research and Education Center published a study in a recent issue of HortScience that determined if winter drought stress could successfully delay flowering and fruit development of immature 'Valencia' sweet oranges to avoid young fruit loss during late-season mechanical harvesting.
The researchers hypothesized that if the Florida 'Valencia' bloom period could be delayed by a few weeks using winter drought stresswithout negative effects on the quality of the current season's cropthe "fruitlets" from delayed flowering would be too small to be affected by mechanical harvesting late in the current harvest season, thus safely extending the mechanical harvesting period.
The study was designed by Juan Carlos Melgar, Jill M. Dunlop, L. Gene Albrigo, and James P. Syvertsen and conducted at the Citrus Research and Education Center in Lake Alfred. Beginning in December 2006 and continuing for three consecutive seasons, Tyvek water-resistive barrier material was used as a rain shield groundcover under 13-year-old-trees. The researchers applied three treatments: drought (no irrigation and covered soil), rain only (no irrigation, no cover),
|Contact: Michael W. Neff|
American Society for Horticultural Science