Postbloom Fruit Drop: It's All About Timing

Harold Browning

Postbloom fruit drop (PFD) in recent years has caused many Florida citrus growers as much, or almost as much, anguish as HLB. The Citrus Research and Development Foundation (CRDF) in December approved an extension of PFD research begun in 2016. CRDF Chief Operations Officer Harold Browning discusses PFD and the research.

“Progressively the last several years, PFD has increased in its importance to the industry, and many this year are saying were it not for PFD, they’d feel a lot better about the (fruit) yields,” Browning says.

He says researchers are testing materials that might help alleviate PFD. “But one needs to remember the most important aspect is the critical timing of when you apply treatments,” he says. “You can’t prevent PFD by treating before the event. So when you have rain during a bloom period and infection is present, you’ve got to be very responsive in timing. So part of what the Extension Service is updating is the importance of timing for control, using the right materials developed for getting out there in the right time frame. We approved an extension to that project to improve on the predictive models that are available, so that they (Extension) could actually tell growers (that) this is a time you really need to be out there or this is a time we haven’t had the combination of events that would lead to it (treatment). Most growers know that, but it doesn’t hurt to reinforce that.”