Using Gibberellic Acid in California Citrus

Josh McGill California Corner, PGRs

Craig Kallsen, University of California Agriculture and Natural Resources (UCANR) citrus and pistachio farm advisor for Kern County, offered suggestions for the use of gibberellic acid (GA3) on citrus in the San Joaquin Valley. Highlights follows: See Kallsen’s full article on gibberellic acid use here. Source: UCANR Sponsored ContentProtect Your Groves From Citrus LeafminerMay 29, 2023Application Tips to Protect Your …

Gibberellic Acid Applications: Day vs. Night

Josh McGill HLB Management, PGRs, Tip of the Week

By Alessandro Franco, Faisal Shahzad and Tripti Vashisth Gibberellic acid (GA) is one of the most commonly used plant growth regulators which affects flowering, fruit and vegetative growth. Multiple monthly GA foliar applications have reduced preharvest fruit drop and increased yield in huanglongbing (HLB)-affected sweet oranges. The potential impact of these findings is huge for commercial citrus production. However, there …

Gibberellic Acid Shows Promising Results on Hamlin

Josh McGill HLB Management, PGRs, Research

By Tripti Vashisth and Taylor Livingston Grower-led trials in 2022 showed positive results of gibberellic acid (GA) treatment on Hamlin trees in Florida. This article primarily discusses two growers’ trials in detail. Both sites showed improvement in fruit production from the GA application. Many growers have adopted GA applications in the past year as part of their grove management strategy. …

Get the Timing Right for Gibberellic Acid Applications

Josh McGill HLB Management, Tip of the Week

By Tripti Vashisth Since 2021, a number of Florida growers have adopted the use of gibberellic acid (GA) in their grove management programs. This widespread adoption is due to the fact that GA-treated trees show canopy rejuvenation and reduction in preharvest fruit drop, resulting in improved yields. The research on Valencia shows that the effect of GA improves over time. …

Gibberellic Acid May Help Citrus Trees After a Hurricane

Josh McGill All In For Citrus Podcast, hurricane

In the latest episode of the All In For Citrus podcast, ways to mitigate damage from Hurricane Ian are discussed by researchers from the University of Florida Institute of Food and Agricultural Sciences (UF/IFAS). While extensively damaged trees are likely lost, those that experienced less damage can be helped in the recovery process. Tripti Vashisth, UF/IFAS associate professor of horticultural …

Gibberellic Acid Continues to Show Benefits

Josh McGill Citrus 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 …

Optimizing Gibberellic Acid Applications in Florida Citrus

Josh McGill Fruit 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 …

Gibberellic Acid Not Recommended in Spring for HLB Trees

Josh McGill HLB Management, Production, Tip of the Week

By Tripti Vashisth Recent research has shown benefits of gibberellic acid (GA) application (monthly from September to January) in improving yield and canopy density of HLB-affected trees. These findings have caught the attention of Florida citrus growers. Many have indicated that they are applying GA in their groves as per the University of Florida Institute of Food and Agricultural Sciences …

Gibberellic Acid Application on Hamlin Appears Promising

Josh McGill Research

By Tripti Vashisth In a multi-year field trial, University of Florida Institute of Food and Agricultural Sciences (UF/IFAS) researchers have seen beneficial effects of gibberellic acid (GA) on Valencia sweet oranges. Monthly application of GA (September to January) on Valencia improved yield on average by 30%, reduced fruit drop and elicited enhanced plant defense response. These benefits are possibly due …

Gibberellic Acid Label Concerns Allayed

Ernie Neff All In For Citrus Podcast, HLB Management

University of Florida Institute of Food and Agricultural Sciences (UF/IFAS) researchers have found that gibberellic acid (GA) applications can improve productivity of HLB-affected Valencia trees. But some growers are concerned that the GA label may not allow that use. Citrus Research and Education Center Director (CREC) Michael Rogers allays that concern. Rogers says some are concerned “because the recommendations that …

Gibberellic Acid Use: Considerations and Concerns

Tacy Callies HLB Management, Tip of the Week

By Tripti Vashisth Gibberellic acid (GA) is a naturally occurring plant hormone. GA has been used in citrus production for years to improve fruit set and size, reduce preharvest drop and delay harvest. Recent findings show that monthly foliar application of GA from September to January can improve productivity of HLB-affected Valencia trees. On average, a 30% increase in yield …

nutrition

Gibberellic Acid for HLB-Affected Trees

Ernie Neff HLB Management

Horticulturist Tripti Vashisth discussed the use of gibberellic acid (GA) in HLB-affected trees at a recent, well-attended OJ Break in Bartow hosted by multi-county citrus Extension agent Chris Oswalt. Vashisth is an assistant professor at the University of Florida Institute of Food and Agricultural Sciences Citrus Research and Education Center. Vashisth told growers that HLB-affected trees are under continuous stress …

Florida orange

The Promise of Gibberellic Acid

Josh McGill HLB Management, PGRs

Researcher Tripti Vashisth shed additional light on the promise of gibberellic acid (GA) applications in rejuvenating HLB-affected orange trees during a Jan. 11 presentation. Some of the important messages that the University of Florida Institute of Food and Agricultural Sciences associate professor highlighted were: VALENCIA TRIALIn a 2016 to 2022 Valencia field trial, GA applications made from September to January …

It’s Almost Time to Spray Gibberellic Acid

Josh McGill HLB Management, Tip of the Week

By Tripti Vashisth Gibberellic acid (GA) can benefit citrus trees in many ways. GA can improve vegetative and fruit growth while reducing fruit drop and flowering intensity. Evidence is mounting that repeated application of GA is needed to induce the desired positive effect on fruit growth and tree productivity. In a multiyear field trial on Valencia orange, monthly application of …

Improve Yields With Gibberellic Acid

Ernie Neff HLB Management

Many Florida citrus growers were among the approximately 300 people who registered for a Sept. 21 virtual seminar telling how gibberellic acid (GA) can improve Valencia orange yields. Valencias, at 30.1 million boxes, made up slightly more than half of Florida’s total citrus crop in the 2020-21 season. Presenter Tripti Vashisth started her presentation by saying that GA, already available …

Gibberellic Acid: Increase Fruit Size and Yield, Reduce Drop

Tacy Callies Production

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 …

production

Production Benefits of Gibberellic Acid

Ernie Neff Production

Gibberellic acid (GA), a plant growth regulator (PGR), has the potential to aid production. It can reduce citrus flowering, improve fruit size, reduce fruit drop and possibly improve tree health, says researcher Tripti Vashisth. Vashisth is a horticulturist with the University of Florida Institute of Food and Agricultural Sciences (UF/IFAS) at the Citrus Research and Education Center (CREC) in Lake …

HLB-affected trees

PGRs for HLB-Affected Trees: An Update

Daniel Cooper HLB Management, PGRs

Using the plant growth regulators (PGRs) cytokinin in spring, gibberellic acid (GA) in summer and 2,4-D in late fall can be helpful for HLB-affected trees, horticulturist Tripti Vashisth reported. Her PGR update came during a Feb. 21 OJ Break. Multi-county citrus Extension agent Chris Oswalt hosted the event at the University of Florida Institute of Food and Agricultural Sciences Citrus …

pgrs

PGRs: Multipurpose Tools for Citrus Improvement

Daniel Cooper PGRs, Tip of the Week

By Tripti Vashisth Canopy health of HLB-affected citrus has been directly related to disease severity, fruit drop and overall fruit production. Some success has been found with the use of certain plant growth regulators (PGRs) such as gibberellic acid (GA) and 2,4-dichlorophenoxyacetic acid (2,4-D) to achieve healthier trees with reduced fruit drop and increased production. HLB MANAGEMENT Application of these …