crop load

Understanding Crop Load and Alternate Bearing

Daniel CooperProduction

By Fernando Alferez and Muhammad A. Shahid Citrus trees bloom profusely. It is estimated that a healthy adult tree can produce more than 200,000 flowers every year. This number is much higher than that of fruits the tree can maintain and develop. Normally only between 1% to 5% of flowers set fruit that develops, matures and can ultimately be harvested. …

water status

Tree Water Status May Predict Citrus Cracking

Daniel CooperIrrigation, Research, Water

New research suggests that how citrus trees respond to water stress may be more important than simply how much water they receive. The findings could help growers improve irrigation management, reduce fruit cracking and protect yields as weather becomes more variable. An article about the study — “Linking plant water status dynamics to yield and fruit cracking in citrus orchards …

citrus species

Citrus Species Show Different Responses to HLB

Daniel CooperHLB Management, Research

Researchers are studying why some citrus species appear to handle huanglongbing (HLB) better than others. Understanding these differences could help breeders develop more resilient citrus varieties and rootstocks for future production. A new study compared nine citrus species infected with HLB and identified differences in how the plants respond to the disease, including changes in nutrient levels, stress responses and …

American

USDA To Buy Fresh Citrus From American Growers

Daniel CooperFresh, USDA

The U.S. Department of Agriculture (USDA) on July 23 announced its intent to purchase $32.5 million of fresh citrus from American growers. USDA’s Agricultural Marketing Service, under Section 32 of the Agriculture Act of 1935, will make the purchases. The fresh citrus will be distributed to food banks and nutrition assistance programs across the country. The fresh citrus purchases will …

Peel

Assessing Citrus Varieties for Peel Benefits

Daniel CooperResearch, Varieties

Many people throw away citrus peels because they are too bitter to eat raw, but this outer layer of the fruit’s skin is a rich source of many sought-after beneficial compounds. The peel is in demand for companies seeking to use those compounds for health and pharmaceutical products.  Christina Dorado, lead scientist and chemist at the U.S. Department of Agriculture …

resistance

Research in Brazil on Greening Resistance

Daniel CooperBreeding, HLB Management, Research

Following the discovery of non-commercial citrus plants resistant to greening disease, Fundecitrus researchers in the field of biotechnology have been working to understand the mechanisms underlying this resistance. The Brazilian scientists also seek to identify viable pathways for transferring these traits to commercial varieties. In 2019, hypotheses were confirmed showing that certain citrus species native to Oceania, such as Eremocitrus …

standard

California Weighs In on OJ Standard Change

Daniel CooperCalifornia Corner, Orange Juice, Regulation

Like the Florida citrus industry, California Citrus Mutual (CCM) welcomed the recent U.S. Food and Drug Administration (FDA) update of the federal standard of identity for pasteurized orange juice (OJ). The action marks the first significant revision to the standard in more than 60 years and takes effect Aug. 19. The FDA reviewed consumer sensory data during its rulemaking process …

young

Two-Step HLB Defense for Young Trees

Daniel CooperIPCs, Research

A newly published study suggests that the use of individual protective covers (IPCs) followed by monthly applications of homobrassinolide (HBr) after IPCs are removed is beneficial. The two-step approach can help young mandarin trees stay healthier longer and produce more fruit in Florida’s HLB-endemic environment. The study, “Combining Individual Protective Covers and Homobrassinolide Treatment Prolongs Tree Health and Increases Fruit …

fruit size

Water Management Impacts Fruit Size and Quality

Daniel CooperIrrigation, Research

How much water citrus trees receive during fruit development can have a major impact on fruit size and internal quality, according to new research published in the journal Horticulturae. The study shows that while moderate water stress may improve some aspects of fruit quality, severe drought significantly reduces fruit size and can make fruit much more acidic. Researchers in China …

byproduct

Pectin in Peels Could Be Valuable Byproduct

Daniel CooperResearch

Citrus peel has long been viewed as a byproduct of juice processing, often ending up as animal feed or compost. New research suggests it may deserve much more attention. Scientists found that pectin extracted from citrus peel has excellent functional properties that could increase its value for use in food, beverage and pharmaceutical products. The study was published in the …

Final Citrus Forecast of the Season Ends on a Positive Note

Tacy CalliesCrop Forecast

The final federal citrus crop forecast of the 2025–26 citrus season, issued July 10, projects increased production for Florida citrus varieties compared to the April forecast.   The July forecast, issued by the U.S. Department of Agriculture National Agricultural Statistics Service (USDA NASS), also includes forecasts for other U.S. citrus-producing states. FLORIDAThe final orange forecast for Florida is 12.92 million …

Citrus leafminer

Citrus Leafminers Are Back in Georgia

Daniel CooperGeorgia, Pests

Apurba Barman, assistant entomology professor at the University of Georgia (UGA), recently wrote about citrus leafminer (CLM) damage resuming in Georgia groves. His article provided management recommendations, including timing of insecticides. Edited excerpts follow: PEST DAMAGE As the temperature rises, so does the potential for CLM attack. CLM is a serious pest resulting in feeding damage to young shoots and …

grower

CITRUS NURSERY SOURCE: A Grower Wish List

Daniel CooperCitrus Nursery Source

By Peter Chaires There has been a good bit of talk recently about an anticipated shift in Florida citrus utilization. Some growers, who for many years saw their fruit utilized in processing, are looking for ways to get more of their crop in a fresh market carton for 2026–27. While grapefruit has always been grown with the fresh market in …

vitamin C

Vitamin C Linked to Better Brain Health in Older Adults

Daniel CooperResearch

A new study published in the journal PLOS One suggests that higher vitamin C levels in the blood are associated with healthier brain structure and stronger brain network connectivity in older adults. The research provides another reminder of the potential value of vitamin C-rich foods, including citrus fruits and juices. The study — “Plasma Vitamin C Levels Are Associated With …

NVDMC

CITRUS NURSERY SOURCE: NVDMC Research Focus for 2026–27

Daniel CooperCitrus Nursery Source, Research

By Peter Chaires Spring is planning season for most Florida citrus organizations. New Varieties Development & Management Corp. (NVDMC) is no exception. The board recently met with all breeding teams to review 2025–26 sponsored projects and establish research priorities for 2026–27. Though some aspects of these projects will be covered in greater depth in future articles, this month’s column is …

plant growth

Plant Growth Regulators in California Citrus

Daniel CooperCalifornia Corner, PGRs

University of California Riverside Extension subtropical horticulturist Mary Lu Arpaia recently discussed the uses of the plant growth regulators 2,4-D, NAA and ethylene in California citrus. Her June 9 presentation was part of the Citrus Research Board Webinar Series. 2,4-D One use of 2,4-D in California is to increase fruit size of navel oranges, grapefruit, mandarins and mandarin hybrids. For …

gibberellic acid

Gibberellic Acid Has Multiple Uses in California Citrus

Daniel CooperCalifornia Corner, PGRs

There are numerous preharvest and postharvest uses of gibberellic acid (GA) in California citrus, a University of California Riverside Extension subtropical horticulturist reported during a June 9 webinar. Mary Lu Arpaia’s GA discussion was a major portion of her broader topic of plant growth regulators in California citrus. Her presentation was part of the Citrus Research Board Webinar Series. WHAT …

specialty crops

Florida Citrus Payment Details for Specialty Crop Assistance Program

Daniel Cooperfinancial, USDA

The U.S. Department of Agriculture (USDA) on May 29 announced payment rates and the enrollment period for the Assistance for Specialty Crop Farmers (ASCF) Program. The USDA will issue $1.625 billion in payments to eligible specialty crop producers in response to elevated input costs and market disruptions resulting from foreign competitors engaging in unfair trade practices that impeded specialty crop …

flooding

Flooding Damages South Africa Citrus

Daniel CooperInternational, Weather

Heavy rainfall in South Africa’s Eastern and Western Cape provinces earlier this month — during early mandarin harvesting — caused widespread flooding that is expected to impact production. The U.S. Department of Agriculture Foreign Agricultural Service (USDA FAS) reported that the floods destroyed export-quality fruit and wiped out entire crops for some growers at the peak of the season. The …

meeting

Florida Citrus Mutual Hosts Spring Grower Meeting

Daniel CooperEvents, Florida Citrus Mutual

Florida Citrus Mutual hosted its spring informational meeting for growers at Golden Ridge Groves in Alturas on May 13. Golden Ridge Groves is growing fresh fruit in citrus under protective screen and recently added you-pick and agritourism options for the public. Steven Hall, executive director of the Citrus Research and Field Trial (CRAFT) Foundation, gave an update and recounted the …