By Meryam Manzoor, Jamie D. Burrow, Taylor Livingston and Tripti Vashisth Effective nutrient management and accurate nutritional analysis are critical for tree growth and maximum yield. Historically, nutrient management for healthy citrus trees involved annual leaf sampling from July to August, with subsequent fertilization plans based on a single nutrient analysis. Almost all commercial citrus groves in Florida are affected …
Florida Citrus Commission Actions and HLB
Florida Citrus Commission (FCC) Chairman Steve Johnson recently discussed HLB and several actions and reports from the commission’s December 2024 meeting. The FCC is the governing board of the Florida Department of Citrus. “For almost two decades, we’ve been in a season of fighting HLB, and that fight (while the war is far from over) is changing,” Johnson said. “The tools …
Top Priorities: HLB Resistance and Hurricane Recovery
With 2024 in the rear view mirror, we asked leaders of key citrus organizations what their priorities are for this year. Here’s what they had to say. TREE OF THE FUTURE “For the last 2.5 years, our research strategy at the Citrus Research and Development Foundation has been to kill the bacteria that causes HLB — Candidatus Liberibacter asiaticus (CLas) …
Weathering the HLB Storm
Specialty crop growers might be aware of the disease sweeping through Florida’s citrus industry. Its impact has been tremendous and has tested the survival of the state’s signature crop. This year will mark the 20th anniversary of the official confirmation of citrus greening disease (also known as huanglongbing or HLB) in Florida. In the past two decades, the state’s output …
Study Shows Impact of HLB Bacterium on Roots
A recent study sheds light on the significant effects of Candidatus Liberibacter asiaticus (CLas), the bacterium responsible for HLB, on the root systems of grafted Valencia orange trees. The findings reveal that root system reductions caused by the infection are more extensive than the corresponding aboveground declines. That finding underscores the hidden yet critical impact of the disease below the …
International Project Arms Citrus Industry Against HLB
Australia’s New South Wales (NSW) Government has partnered with the Australian Centre for International Agricultural Research and Hort Innovation to prepare the citrus industry against huanglongbing (HLB). Although widespread in Asia and found in North and South America, HLB is not known to be present in Australia. The psyllid that spreads HLB is also absent from Australia. A collaborative research …
Planting Layout Reduces HLB-Spreading Psyllids
A Brazilian study has shown that planting citrus plots parallel to the property boundary reduced HLB-spreading psyllids 12% to 23% compared to plots planted perpendicular to the property boundary. Fundecitrus conducted the study. The São Paulo Research Foundation co-financed it in partnership with Embrapa. Another study conclusion is related to the impact of planting density on border plots. Fundecitrus researcher …
HLB Quarantine Expanded in California
An area quarantined for huanglongbing (HLB), also known as citrus greening disease, in California was recently expanded. The U.S. Department of Agriculture Animal and Plant Health Inspection Service (APHIS) in cooperation with the California Department of Food and Agriculture (CDFA) issued the expansion. The quarantined area in the Mission Viejo area of Orange County expanded by approximately 85 square miles. …
Progress Being Made in HLB Fight
Texas A&M AgriLife Research scientists led by Kranthi Mandadi are seeking novel solutions to huanglongbing (HLB), also known as citrus greening disease. Mandadi is a professor in the Texas A&M Department of Plant Pathology and Microbiology and a researcher at the Texas A&M AgriLife Research and Extension Center at Weslaco. In the past few years, he and his collaborators have …
Fundecitrus Signs Agreement Seeking HLB Solutions
Nelson Wulff of Fundecitrus recently signed a technical cooperation agreement between Fundecitrus and the National Center of Genetic Resources (Cenargen/Embrapa) for a project to develop biotechnological solutions for HLB. Wulff, coordinator of the Fundecitrus Biotechnology and Diagnostics Laboratory, signed the agreement at the 50th anniversary ceremony of Embrapa Genetic Resources and Biotechnology in Brazil. Embrapa Genetic Resources and Biotechnology has …
Fertilizer Considerations for HLB-Affected Citrus
By John M. Chater and Davie Kadyampakeni Soil fertility is a keystone to a productive citrus grove in Florida. In the era of huanglongbing (HLB), the need to fine-tune soil fertility takes on even more importance. The sandy soils found in citrus-growing regions of the state are great for drainage to reduce flooding stress of citrus trees in many cases, …
Improving ACP and HLB Control in Residential Settings
By Romain Exilien and Xavier Martini Residential gardens serve as reservoirs for Asian citrus psyllids (ACP) and citrus greening disease (also known as huanglongbing or HLB) due to unmanaged citrus trees. The University of Florida Institute of Food and Agricultural Sciences (UF/IFAS) conducted a survey to assess residents’ needs regarding ACP and HLB management. The survey examined their current control …
HLB-Tolerant Hybrid Varieties Highlighted
Two varieties that tolerate HLB and produce ample fruit yield and juice were the highlights of the recent Millennium Block Field Day in Fort Pierce, Florida. The 20-acre Millennium Block at the University of Florida Institute of Food and Agricultural Sciences (UF/IFAS) Indian River Research and Education Center (IRREC) examines fresh fruit varieties and rootstocks. “The two varieties that give …
How to Handle Extended Flowering in HLB Trees
By Tripti Vashisth University of Florida Institute of Food and Agricultural Sciences (UF/IFAS) flower bud induction advisories for 2024–25 started on Nov. 25. The advisories will be posted bi-weekly until March 2025. The goal of the advisories is to provide growers and production managers with a complete overview of flowering prediction. Every advisory will aim to deliver recommendations for that …
New Flame Grapefruit Selection Offers Improved HLB Tolerance
By Manjul Dutt, Sheetal Ramekar and Gary England The grapefruit was created by chance from a cross between a pummelo and a sweet orange. It was first discovered in Barbados in the 18th century. All the commercially sold grapefruits today trace their roots back to the Duncan variety of grapefruit. Cultivars existing today were developed through natural and induced mutations …
HLB Confirmed on California Inactive Citrus Acreage
The California Department of Food and Agriculture (CDFA) has confirmed the detection of the citrus plant disease huanglongbing (HLB) in inactive citrus acreage in the city of Yorba Linda, Orange County. The detections mark the first time HLB has been confirmed in plant samples on non-residential, non-nursery citrus acreage. The detection site, which is not currently operational or being cultivated …
California HLB Quarantine Expanded
Agricultural officials recently expanded the areas in California quarantined for citrus greening disease [also known as huanglongbing (HLB)], which is spread by Asian citrus psyllids. The quarantined area in Orange and Riverside counties was increased by a total of approximately 31 square miles. The U.S. Department of Agriculture Animal and Plant Health Inspection Service (USDA APHIS) in cooperation with the …
Australian Lime Interstocks to Combat HLB
By Ozgur Batuman, Sanju Kunwar and Ana Redondo In a promising effort to protect citrus from huanglongbing (HLB), University of Florida Institute of Food and Agricultural Sciences (UF/IFAS) researchers are exploring the potential of Australian lime as an interstock graft for Valencia scions with Swingle rootstock. The interstock technique uses various limes, known for their natural HLB-tolerant peptides, between the …
Top Pruning Evaluated as HLB Strategy
A Brazilian study evaluated the effects of top pruning on orange trees located on the edges of an orchard as part of an HLB management strategy. The pruning was an attempt to attract the HLB-spreading psyllid from external areas to the orchard edges and control it, reducing its dispersion into the orchard. Fundecitrus and Embrapa Cassava and Fruits conducted the …
Brazilians Visit Indian River to Learn About HLB Management
Several citrus growers, consultants and others from São Paulo, Brazil, recently toured Florida’s Indian River citrus region to examine the management of HLB. Flavia Zambon, University of Florida Institute of Food and Agricultural Sciences (UF/IFAS) assistant professor of horticultural production at the Indian River Research and Education Center (IRREC), hosted the group. “In the traditional production region known as the …