Optimize Zinc and Potassium Applications to Prevent Fruit Drop

Josh McGillFruit Drop, Nutrition, Tip of the Week

By Fernando Alferez, Daniel Boakye, Murillo De Sousa and Pablo Orozco After HLB was first detected in Florida, increase in disease-associated preharvest fruit drop in affected trees has significantly reduced grower returns. Fruit drop is normal in healthy citrus, accounting for 10% to 15% of the total crop. However, under endemic HLB conditions and depending on the variety, crop loss …

Grower Achieves High Brix and Stops Drop

Josh McGillFruit Drop, Organic, Production

Low Brix has been a major problem plaguing the Florida citrus industry in recent years. While many growers are struggling to achieve the minimum required Brix level, this has not been an issue for citrus grower Chip Henry. He recently shared how he believes his organic production techniques contribute to high Brix as well as stopping premature fruit drop in …

Gibberellic Acid Continues to Show Benefits

Josh McGillCitrus Expo, Fruit Drop, HLB Management

Researcher Tripti Vashisth has been telling citrus growers about the benefits of using gibberellic acid (GA) on citrus trees. At the Citrus & Specialty Crop Expo, the University of Florida Institute of Food and Agricultural Sciences horticulturist said GA continues to show efficacy, based on 2022 harvest numbers. Vashisth’s Expo presentation included details from a 2016–2022 study of 10-year-old Valencia …

Extension Agents Assess Hurricane Damage

Josh McGillFruit Drop, hurricane

“Hurricane Ian has devastated much of Florida’s citrus industry,” said Michael Rogers, director of the University of Florida Institute of Food and Agricultural Sciences (UF/IFAS) Citrus Research and Education Center. “The harsh reality is that the 2022–2023 season will be one of the most challenging that any of us has faced.” Several UF/IFAS Extension agents made early assessments of the …

Optimizing Gibberellic Acid Applications in Florida Citrus

Josh McGillFruit Drop, HLB Management

Tripti Vashisth, University of Florida Institute of Food and Agricultural Sciences (UF/IFAS) associate professor of horticultural sciences, has dedicated several years of research into the use of plant growth regulators like gibberellic acid (GA) to fight fruit drop in citrus. In the August All In For Citrus Podcast, Michael Rogers, director of the UF/IFAS Citrus Research and Education Center, interviewed …

Combined Treatment Reduced Drop and Increased Size

Josh McGillFruit Drop, HLB Management, Production

A combination of gibberellic acid (GA) and 2,4-D reduced preharvest fruit drop by 18% and improved fruit size but produced no statistical effect on yield, researcher Tripti Vashisth reported Aug. 30. The combination “seems promising,” the University of Florida Institute of Food and Agricultural Sciences (UF/IFAS) horticulturist stated. The report was based on first year results from a trial of …

April

All In For Citrus Podcast, August 2022

Josh McGillAll In For Citrus Podcast, Fruit Drop, HLB Management

The August episode of the All In For Citrus podcast takes listeners on a deep dive into the use of plant growth regulators like gibberellic acid (GA) to help fight fruit drop. The episode features an in-depth conversation between Michael Rogers, director of the University of Florida Institute of Food and Agricultural Sciences (UF/IFAS) Citrus Research and Education Center, and …

Impact of HLB on Fruit Growth and Retention

Josh McGillFruit Drop, HLB Management

By Tripti Vashisth and Mary Sutton Citrus trees affected by huanglongbing (HLB) consistently have small fruit and low fruit numbers at harvest. The low fruit numbers are largely attributed to the increased rates of preharvest fruit drop that accompany HLB. Small fruit is more likely to drop during this preharvest period, suggesting a link between fruit size and retention. To …

Tips to Keep Citrus Fruit on Trees

Josh McGillAll In For Citrus Podcast, Fruit Drop

By Frank Giles During the May All In For Citrus podcast, Michael Rogers, director of the Citrus Research and Education Center, discussed research on how applications of gibberellic acid (GA) can improve tree health and reduce fruit drop. The research is being conducted by Tripti Vashisth, an associate professor of horticultural sciences with the University of Florida Institute of Food …

Impact of Herbicides on Fruit Drop

Josh McGillAll In For Citrus Podcast, Fruit Drop, Herbicides

Growers know the negative impacts of any kind stress on trees infected by HLB. That raised a question: Can injury from herbicides make fruit drop worse? Ramdas Kanissery, an assistant professor of weed science with the University of Florida Institute of Food and Agricultural Sciences (UF/IFAS), conducted a research project to help answer that question. Kanissery discusses the research in …

Fruit Flies Are Major Cause of Fruit Drop in Brazil

Josh McGillBrazil, Fruit Drop, Pests

Brazil’s Fundecitrus recently pointed out that fruit flies, along with citrus fruit borers, are primarily responsible for the country’s citrus fruit drop. The organization suggested that monitoring and management must be taken to avoid economic damage, since fruit flies occur throughout the year. Fundecitrus described the fruit flies that cause damage in Brazil and suggested control measures.   Two species of …

citrus

All In For Citrus Podcast, May 2022

Josh McGillAll In For Citrus Podcast, Fruit Drop, Research

Fruit drop continues to plague Florida citrus groves. Growers and researchers are seeking ways to mitigate the problem. This was the topic of a number of presentations during the Florida Citrus Growers’ Institute held in Avon Park in April. Michael Rogers, director of the Citrus Research and Education Center in Lake Alfred, discusses those presentations during the May All In …

Herbicides and Fruit Drop

Josh McGillFruit Drop, Research, weeds

Weed scientist Ramdas Kanissery’s research has not shown evidence that herbicides, including glyphosate, increase citrus fruit drop or decrease yields. But in studies using different glyphosate rates, he did find that there is a relatively strong negative correlation with the fruit detachment force and the glyphosate amount applied. “That means there may be something happening with the higher glyphosate rate” …

Webinar to Address PGRs and Fruit Drop

Josh McGillFruit Drop

Florida citrus growers can learn more about the use of plant growth regulators (PGRs) in the fight against fruit drop at an upcoming online seminar. The webinar will be at 10 a.m., April 27 and will be presented by the University of Florida Institute of Food and Agricultural Sciences (UF/IFAS). Speakers at the webinar, titled “Gibberellic Acid Research Update and …

Be Prepared for Postbloom Fruit Drop

Josh McGillFruit Drop, Research

A La Niña weather pattern is most likely this spring, with higher-than-average temperatures and below-average rain predicted in Florida, researcher Megan Dewdney reported in a Feb. 24 presentation about postbloom fruit drop (PFD). That could have some influence on the severity of PFD, since its preferred climate is humid and subtropical, and the fungus moves with rain splash and wind-borne …

Florida Citrus Growers Seeking Solutions to Fruit Drop

Josh McGillCitrus, Florida, Fruit Drop

Fruit drop has plagued Florida citrus groves in recent years. The problem has been a major factor in tumbling yields. The February 2022 U.S. Department of Agriculture’s citrus crop forecast put Florida’s orange estimate at 43.5 million boxes. If realized, it would represent an 18% decline in the crop from last season. Growers are turning over every stone to seek …

Can Zinc and Potassium Curb Fruit Drop?

Tacy CalliesFruit Drop

The Florida citrus industry has been focused on finding solutions to the fruit drop problem that has hit groves hard in recent years. During the 2022 Florida Citrus Show in Fort Pierce, Fernando Alferez, University of Florida Institute of Food and Agricultural Sciences, assistant professor of citrus horticulture, presented findings from a research trial aimed at reducing fruit drop. The …

Keep an Eye Out for Postbloom Fruit Drop This Spring

Josh McGillFruit Drop, Tip of the Week, Weather

By Megan M. Dewdney Postbloom fruit drop (PFD) is a flower disease mainly caused by the fungus Colletotrichum acutatum. The fungus is present on citrus trees throughout the year but survives by producing resting structures on leaves and stems. The fungus becomes stimulated to produce spores by substances from the early flowers. These early spores infect the initial flowers and …