Citrus Production Guide: Plant Growth Regulators

Citrus groves around Lake Alfred, Florida. Oranges, fruit, trees. UF/IFAS Photo by Tyler Jones.

Plant growth regulators (PGRs) are a tool used to manipulate vegetative and reproductive growth, flowering, and fruit growth and development. PGRs have been successfully used in agriculture for decades to amend plant growth characteristics to maximize yield and grower profit. This new 4-page fact sheet discusses auxins, gibberellins, cytokinins, abscisic acid, ethylene, new classes of plant hormones, use of PGRs for HLB-affected trees, and general considerations for PGR use in Florida citrus groves. Written by Tripti Vashisth, Chris Oswalt, Mongi Zekri, Fernando Alferez, and Jamie D. Burrow, and published by the UF/IFAS Horticultural Sciences Department, February 2018.
http://edis.ifas.ufl.edu/hs1310

Citrus Production Guide: Rootstock and Scion Selection

Oranges on trees in a grove at the Citrus Research and Education Center. Photo taken on 03/04/16.When preparing for replanting, an important factor to consider is the choice of rootstock. Choosing the right rootstock and scion combination can result in higher economic returns without any additional cost. Rootstocks affect scion vigor, yield, fruit size, juice quality, and pest tolerance. However, tree growth, yield, and fruit quality interact strongly with climate, soil type, tree spacing, and other factors, often producing contradictory reports on rootstock performance in different areas. This 3-page fact sheet discusses soil characteristics, rootstock effects on pests and diseases, tree spacing and size, and rootstock/scion combination. Written by Ute Albrecht, Fernando Alferez, and Mongi Zekri, and published by the UF/IFAS Department of Horticultural Sciences, September 2017.
http://edis.ifas.ufl.edu/hs1308

2017-2018 Florida Citrus Production Guide: Fresh Fruit Pesticide Residue Limits

Grapefruit.

Current citrus production practices often include the use of various chemicals, many of which are pesticides. Chemical residues on the fruit after harvest are a concern to regulators and the public alike because of their potential negative health effects. Therefore, the US and other countries set maximum residue limits (MRLs) on fresh produce for various chemicals. This five-page document is part of the 2017-2018 Florida Citrus Production Guide and discusses the MRLs for various chemicals used on Florida citrus. Written by Mark Ritenour and published by UF’s Horticultural Sciences Department, October 2017.
http://edis.ifas.ufl.edu/hs1301