By Tripti Vashisth, Lisa Tang and Sukhdeep Singh In citrus, huanglongbing (HLB) causes an increase in the mature fruit drop rate up to three months prior to commercial harvest. This preharvest fruit drop results in a great reduction in yield and overall grove productivity. Since the plant growth regulators that improve fruit retention on healthy trees do not have consistent …
Thermotherapy’s Effects on Fruit Drop, Yield and Quality
By Megan Dewdney, Evan Johnson, Naweena Thapa and Michelle Danyluk In 2015, we started a large-scale project to determine if thermotherapy would be an effective huanglongbing (HLB) treatment for field trees. Some of the objectives were to determine effective temperature-time combinations for thermotherapy, which season gave optimal results for thermotherapy, and the effect on yield in subsequent years. TRIAL DETAILSComprehensive …
Fruit Drop and HLB
By Tripti Vashisth and Lisa Tang Fruit drop is a natural, physiological phenomenon that occurs in all citrus varieties. However, pre-harvest fruit drop often causes grower distress and concern as it can result in significant yield reduction as well as loss of tree resources into non-harvested fruit. THREE PERIODS OF FRUIT DROP In general, citrus trees bloom profusely in spring, …
How to Handle Glyphosate-Related Fruit Drop
By Ramdas Kanissery, Fernando Alferez and Ozgur Batuman Herbicides are one of the key inputs necessary for effective management of a wide diversity of weed infestations in citrus crop production. Most weeds in citrus could be controlled by adopting a weed management program that utilizes a combination of herbicides based on their selectivity and compatibility with the crop. This would …
HLB Management, PGRs and Fruit Drop
Column sponsored by the Citrus Research and Development Foundation Plant growth regulators (PGRs) are chemicals that increase or decrease plant growth, flowering and/or fruit set. PGRs include some herbicides. This article summarizes research studies on how PGRs might aid in the management of HLB. Although several successful herbicide practices were developed by University of Florida Institute of Food and Agricultural …
Outlook for Postbloom Fruit Drop
By Megan M. Dewdney, Tripti Vashisth and Ariel Singerman In 2017, the damage from postbloom fruit drop (PFD) was lower than the previous three years. This was mainly due to the low rainfall accumulation in late winter and early spring. The long bloom with relatively few flowers at any one time made the decision of when to apply a fungicide …
Will You Be Ready for Postbloom Fruit Drop?
By Megan M. Dewdney Again in 2016, postbloom fruit drop (PFD) caused widespread problems in Florida groves. There were multiple factors that contributed to the outbreak in 2016. The primary factor was likely the extended bloom that many saw because of a combination of tree stress caused by huanglongbing (HLB) and the very warm winter. Bloom in some groves was …
Brazilian Discusses Postbloom Fruit Drop
Geraldo Silva, a scientist with Fundecitrus in Brazil, shared thoughts about postbloom fruit drop (PFD) and its control at a recent seminar in Arcadia. Silva says Brazilians assume that the PFD inoculum is present in groves at all times, because consecutive days of rain can bring on a PFD outbreak 10 years after a previous outbreak. “We can have a …
Postbloom Fruit Drop: It’s All About Timing
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 …
Postbloom Fruit Drop Control: Timing Is Key
Timing of fungicide sprays is the key to controlling the postbloom fruit drop (PFD) that caused many Florida citrus growers severe problems this year. That was a central message that University of Florida researcher Natalia Peres delivered at Citrus Expo this summer. In this interview, Peres discusses the keys to proper spray timing, starting with bloom. Peres says longer bloom …
Post-Hurricane: Some Fruit Drop on River; Interior Mostly OK
Heavy winds from Hurricane Matthew Friday caused some fruit drop in the Indian River citrus area. But the amount of drop was “not catastrophic,” said Florida Citrus Mutual spokesman Andrew Meadows. “The fact that it stayed offshore helped tremendously,” Meadows said. Some Indian River growers and packers told Mutual that in addition to fruit drop, there will likely be some …
Post-Bloom Fruit Drop Survey
A Citrus Research and Development Foundation (CRDF) Research Management Committee meeting was called on June 29, 2016, to discuss post-bloom fruit drop (PFD) caused by Colletotricum spp. in Florida. In this meeting, it was suggested that there is an opportunity to retrospectively investigate PFD management strategies from 2016 to determine if grower treatment programs led to variable results. A survey …
Global Grapefruit and Mandarin Crops to Drop
A report from the U.S. Department of Agriculture Foreign Agricultural Service (USDA FAS) projects world grapefruit and tangerine/mandarin crops will decline in 2024–25 from the previous season. GRAPEFRUIT Global grapefruit production for 2024–25 is forecast down slightly to 6.9 million tons as decreases in Türkiye and the United States more than offset higher production in China. Exports and fruit for …
Brazil’s Orange Forecast: Less Fruit, More Drop
The 2020–21 orange crop forecast for the São Paulo and West-Southwest Minas Gerais citrus belt in Brazil is 269.36 million boxes. The updated forecast was published Dec. 10 by Fundecitrus and its cooperators. The decrease of 17.36 million boxes represents a 6 percent decline in crop size from the September forecast update. ADVERSE WEATHER CONDITIONSExpected production was significantly hindered by …
Gibberellic Acid: Increase Fruit Size and Yield, Reduce Drop
By Tripti Vashisth and Megan Dewdney This article discusses the use of gibberellic acid (GA), the naturally occurring plant hormone, on huanglongbing (HLB)-affected trees. The results were generated from a 3-year trial in which Valencia trees were treated with GA in the fall. The outcomes suggest that GA can be effectively used for synchronizing and suppressing profuse flowering without negatively …
Grapefruit Production Costs Drop; Profitability Is Elusive
A decrease in grapefruit production costs among Indian River growers allowed the average grower to approach the break-even point in the 2015-16 season, a University of Florida economist reports. Ariel Singerman made his report at the recent Florida Citrus Show in Fort Pierce. The report was based on a July 2016 survey of 70 growers representing a majority of grapefruit …
Brazil’s Orange Crop Forecast Drops Again
Fundecitrus’ Dec. 10 orange crop forecast for the São Paulo and Triângulo/Southwest Minas Gerais Citrus Belt in Brazil is for 294.81 million boxes of oranges. That’s a reduction of 3.9% from the September forecast of 306.74 million boxes and a 6.3% reduction from the initial May forecast of 314.6 million boxes. The two main reasons for the reduction in the …
Texas Citrus: Heavy Crop but Smaller Fruit
Texas citrus is showing heavy crops, but limited summer irrigation has led to smaller fruit sizes so far, said Juan Anciso of Texas A&M AgriLife Extension Service. Anciso is an AgriLife Extension vegetable specialist and associate head of the Department of Horticultural Sciences at the Texas A&M AgriLife Research and Extension Center in Weslaco. According to Anciso, quality continues to remain good to …
The European Citrus Fruit Market
A report from IndexBox indicates Europe’s citrus fruit market will grow steadily over the next decade in both volume and value. The market is projected to increase to 13 million tons by the end of 2035, with a market value of $14 billion (in nominal wholesale prices). RECENT FIGURES The revenue of the citrus fruit market in the European Union …
Injection Month Affects Fruit Size, Juice Quality and OTC Residues
By Ute Albrecht, Gabriel Pugina, Caroline Tardivo, Jasmine de Freitas and Deived de Carvalho The month during which oxytetracycline (OTC) injections are performed can have a considerable impact on fruit size, juice quality and OTC fruit residues. Citrus fruit development can be divided into three overlapping stages: If injections are performed during Stage I, they promote cell division, which increases …





























