Flower Bud Induction Overview and Advisory

Flower Bud Induction

 

NOTICE FOR CITRUS EXTENSION AGENTS & SPECIALISTS AND GROWER NEWSLETTERS
The following information has been developed as part of the Decision Information System for Citrus

L.  Gene Albrigo, Horticulturist Emeritus
Citrus Research & Education Center, Lake Alfred, FL

 

Archives of past Flower Bud Induction Advisories

 

FLOWER BUD INDUCTION ADVISORY #7a for 2016-2017-2/16/17

This is a note regarding yesterday's rain and potential for PFD development. Dr. Natalia Peres thinks the rain yesterday should not be much of a problem for development of PFD. At least in the Central Ridge Area the duration was short and the wind dried off the plants very quickly. Fawn sites all seem to have had fairly low rainfall. We saw about .1 to .5 inches in about ½ hour.

FLOWER BUD INDUCTION ADVISORY #7 for 2016-2017-2/15/17

Flower Bud Induction Overview and Advisory
NOTICE FOR CITRUS EXTENSION AGENTS & SPECIALISTS AND GROWER NEWSLETTERS
The following information has been developed as part of the Decision Information System for Citrus

L. Gene Albrigo, Horticulturist Emeritus
Citrus Research & Education Center, Lake Alfred, FL

FLOWER BUD INDUCTION ADVISORY #7 for 2016-2017-2/15/17
This is a service to our citrus growers posted on the CREC website. The indicated Expert System on intensity and time of bloom can be accessed at the designated Web Site: http://disc.ifas.ufl.edu/bloom

If you are not familiar with the website and flower bud induction in citrus you should read the overview section in the first advisory this year.

nduction  and flowering status – The Citrus Flowering Monitor System indicates that all Florida citrus areas can have up to three waves of flowers during the normal bloom period.  With the winter off-season bloom that could be as many as 4 waves of flowers this year. The model projected a February 8-22 first wave full bloom with about 630 to 800 inductive hours, followed by a second wave around 3 to 16 March with 830 to 1000 inductive hours, and a final wave from March 16 to April 3rd with 1000 to 1200 inductive hours. Generally the earlier dates for each wave are in the southern areas and the higher inductive values are in the northern areas for each flowering wave.

I have only looked at two blocks, one Valencia and one Hamlin, to see how they related to the model. In each block young fruitlets (winter bloom), large popcorn to petal fall (mid-February bloom), small popcorn to large pinhead (predicted early March bloom), and small pinhead (late March projected bloom) were observed.  The current February wave was clearly the largest with some fruitlets (winter bloom) and the second regular wave easy to find but in much fewer numbers than the current flowering wave.  Some small pinhead flowers were visible in very small numbers.  There will be block-to-block variability but the relative number of flowers per tree should follow this trend.

Potential for PFD – We will have flowering overlap until well into or all of March.  Natalia Peres (a PFD expert at Balm) says that any white petal surface is susceptible, past pinhead until petal fall. Ovary stigma may be susceptible also. Warmer temperatures with a long leaf wetness period makes for most likely infection. Using current products, a spray following potential infection probably needs to be applied within one day after unfavorable conditions. A local production manager I talked with today hasn’t seen much if any PFD symptoms on flower petals in their groves up to now. He was concerned about potential rain today and Friday but the weather channel suggests that rain is more likely to occur in the north central region with less chance of rain Friday.

If you have any suggestions or questions, please contact me (albrigo@ufl.edu)