Using Man’s Best Friend to Detect Citrus Greening

Using Man’s Best Friend to Detect Citrus Greening

For decades, humans have relied on dogs to detect explosives, illegal drugs, lost people and wildlife. More recently, they have been used to detect pests such as termites, bedbugs and agricultural insect pests. Now, we can add agricultural diseases to the list.

Huanglongbing (HLB) or citrus greening is the major disease limiting citrus production in Florida, and is responsible for the 75% decline in Florida’s $9 billion citrus industry. The disease is caused by the bacterium, Candidatus Liberibacter asiaticus and is spread primarily by the Asian citrus psyllid, although it can also be transmitted through infected plant tissue.

Once a tree becomes infected with HLB, there is no cure, and visual symptoms of the disease after infection may take months, even years to appear. During that time, the disease can spread rapidly, destroying existing groves. Early detection and the removal of infected trees is the most effective method to prevent an HLB epidemic. At present, the most common method for diagnosing HLB is visual inspection through scouting; however, once the disease is observed, it is likely too late. Scientists with the United State Department of Agriculture (USDA) Agricultural Research Service (ARS) have been evaluating the use of scent-detecting dogs for the early detection of HLB infected trees and their method is proving to be successful.

The mulit-year study has been funded by a grant from the USDA Animal and Plant Health Inspection Service (APHIS) HLB Multi-Agency Coordination (MAC) program, and a partnership between F1K9 Kennels. Through the F1K9 training academy located in Florida, twenty dogs have been trained to recognize the volatile compounds emitted from trees infected with HLB. In the field, the dogs run with their handler along the grove row, sniff each individual tree and alert on trees infected with HLB. After alerting to an infected tree, dogs are rewarded by verbal praise and short playtime with their handlers.

Data from studies show that the dogs have a 99% detection accuracy rate, and when two or more dogs alert to the same tree, the tree has a 100% probability of infection. Additionally, the dogs were able to detect trees inoculated with HLB within 2-3 weeks after inoculation. The same trees were sampled using polymerase chain reaction (PCR) testing (the standard HLB detection method) and did not test positive for HLB until three to six months after inoculation, confirming that the scent-detecting dogs are a useful tool for early detection of HLB.

The true value of the scent-detecting dog method is not in South Florida where HLB is already at an epidemic level, but in regions where HLB is not as widespread. This year, the Florida scent-detecting dogs will be traveling to California to aid in the fight against preventing the spread of HLB in commercial plantings.

In the Florida Panhandle, confirmed cases of citrus greening or HLB and established psyllid populations have been geographically isolated, with the majority being in residential citrus plantings and not commercial groves. Therefore, an early detection method like this, paired with a rapid removal of HLB-infected trees may be a useful tool to help minimize disease spread and optimize planting longevity for newly planted acreage in North Florida and South Georgia where HLB incidence is low.

For more information on this topic, use the links to the following publications:

Canine Assisted Early Detection of HLB

HLB Early Detection Methods Available Now



New Phone App Connects Beekeepers and Growers

New Phone App Connects Beekeepers and Growers

Source: Pollination Network

Pollination Network, a mobile app that helps local farmers and growers find bees and beekeepers, launched this week in the Apple App Store and Google Play Store. The app helps beekeepers to find jobs with nearby growers, and it allows growers to post public listings and hire beekeepers within the app.

It’s become more and more difficult for growers to find bees over the years,” said Brandon Bouye, owner and founder of the app. “But it’s been just as hard for beekeepers to keep their hives growing and their businesses afloat. We wanted to change that.”

When beekeepers download the app, they will have access to a map featuring job listings from growers across the country who need bees. They can filter by location, expected price rate, and quality of bees, and apply for jobs straight from the app.

Growers will be able to post listings from their smartphones, customizing each job listing to their specific needs. Then, employees at the Pollination Network headquarters will manage the listings and notify growers when a suitable beekeeper is found.

Strengthening the grower-beekeeper relationship doesn’t just improve a tiny corner of the economy,” Bouye said. “It protects the environment, and it puts food on the table for people across the country.”

The Pollination Network app can be downloaded for free in the Apple App Store and Google Play. Pollination Network is a niche app that connects beekeepers with farmers and growers for timely pollination and healthier, more fruitful crops.

App Store linkGoogle App Store link



For more information, visit, or contact:
Gina Alonso
(909) 583-7838

Farm Food Safety Certification Training – January 23

Farm Food Safety Certification Training – January 23

A Produce Safety Alliance (PSA) Grower Training is scheduled for Wednesday, January 23 at the Escambia County Extension Office in Cantonment, FL.  The PSA Grower Training curriculum is approved by the FDA to meet the requirements of the Food Safety Modernization Act (FSMA) Produce Safety Rule.

Who Should Attend? – Fruit and vegetable growers with farms that have an annual value of produce sold (based on a three year average) of $25,000 (adjusted for inflation) or more.

Benefits to Attending – The course will cover the requirements of the FSMA produce safety rule.  It will also cover key Good Agricultural Practices (GAPs) and Standard Operating Procedures (SOPs) that are necessary in a farm food safety plan.

Cost to Attend – The fee for the training is $25 for farmers and government/university employees ($125 for all others).  For general registration questions contact Jessica Lepper at  Participation for the entire training is required for the certificate.  Training materials and certificate are funded through the Florida Department of Agriculture and Consumer Services (FAIN #U18FD005909).


Registration Deadline is January 17, 2019


  • 8:30 Registration and Refreshments
  • 9:00 Welcome and Introductions
  • 9:15 Module 1: Introduction to Produce Safety
  • 10:00 Module 2: Worker Health, Hygiene, and Training
  • 11:00 Break
  • 11:15 Module 3: Soil Amendments
  • 12:00 Module 4: Wildlife, Domesticated Animals, and Land Use
  • 12:45 Lunch
  • 1:30 Module 5: Agricultural Water Part 1: Production Water
  • 2:15 Part 2: Postharvest Water
  • 3:15 Break
  • 3:30 Module 6: Postharvest Handling and Sanitation
  • 4:30 Module 7: How to Develop a Farm Food Safety Plan
  • 5:00 Final Questions and Evaluations

Critical Carrot Diseases for North Florida and a Disease Management Plan for 2019

Critical Carrot Diseases for North Florida and a Disease Management Plan for 2019

Susannah Da Silva, Fanny Iriarte, Bob Hochmuth and Mathews Paret, UF/IFAS North Florida Research and Education Center

Carrots are produced in Florida on an estimated area of 4,000 acres; most of which are in North Florida. The planting time for carrots in North Florida is August – December, with crops taking anywhere from 120-150 days to reach maturity. With weather conditions varying so much during the crop cycle, it makes carrots a prime target for several fungal pathogens. Surveys conducted by a UF/IFAS research team at the North Florida Research and Education Center (NFREC), Quincy and Live Oak, from 2015-2018 detected three main diseases that might be encountered during this growing season. A summary of these diseases, and periods of the year when they could be a problem are shown below.

Cottony Rot

Cottony Rot (called white mold on other vegetables), caused by the fungus Sclerotinia sclerotiorum, is active from December through April in North Florida.  It appears later in the season and can even affect plants after harvest. Symptoms can include brown lesions on lower foliage, or on the tops of carrots. A cottony white mold will form on the plant near the soil line and will eventually produce black sclerotia (Fig. 1). For disease management, see the 2018-2019 Vegetable Production Handbook of Florida, and Integrated Management of White Mold on Vegetables in Florida.

Cottony rot

Fig. 1. Cottony rot on carrot (left) and black sclerotia (right) collected from the soil line.

Alternaria Blight

Alternaria blight is caused by at least two species of Alternaria. The disease is most active from January to June in North Florida, and occurs most often under wet conditions, with temperatures ranging from 60-77°F. Symptoms initially appear as water-soaked spots and leaf marginal necrosis, but as the disease progresses, lesions become dark brown to black, and sometimes present chlorotic halos with yellowing of the surrounding leaf area. Lesions expand to turn entire leaf dark brown or black (Fig. 2). Symptoms may also appear on stems of the carrot tops. This disease can cause the foliage to drop off, making harvesting difficult, as at least 50% of the foliage is required for the common harvester, which pulls the carrot tops mechanically. Alternaria spp. is spread by spores, which can be moved by the wind, water splashing, or other mechanical means.

carrot leaf blight

Fig. 2. Leaf blighting on carrot caused by Alternaria spp.

Over the the fall 2017  through spring 2018 growing season, an experiment was conducted to test the efficacy of a fungicide rotation program that used protectant and systemic fungicides. Disease severity evaluations taken for several weeks were used to determine the efficacy of the fungicide rotation program in comparison to a water only control. The fungicide rotation program (Table 1) kept the disease well below the maximum threshold (50% of the disease severity/blighting), and allowed for efficient use of a mechanical harvester, as indicated by the final disease severity data (Fig. 2). The disease severity of the water control was above the maximum threshold of disease severity.

Disease Severity chart

Fig. 2. Percentage disease severity of Alternaria blight indicating efficacy of a fungicide rotation program in comparison to the water control.

Southern Blight

Southern Blight (Sclerotium rolfsii) is active from April to June in North Florida.  This disease can damage foliage, but mostly affects carrot roots. Ideal conditions for this pathogen are moderately cool to warm temperatures, following wet conditions. Symptoms appear as a white fan like fungal growth at the crown of the plant, which eventually form sclerotia (small, white  to mustard colored) (Fig. 3). Sclerotia can spread the pathogen and survive for many years in the soil. The pathogen can spread from plant to plant through the soil, and can spread between fields on farm equipment. For disease management, see the Vegetable Production Handbook of Florida.

Fungal Sclerotia

Fig. 3. Sclerotia of Sclerotium rolfsii are mustard like fungal structures usually found at the base of infected plants.

Hurricane Michael Agricultural Damage Assessment and Economic Impacts

Hurricane Michael Agricultural Damage Assessment and Economic Impacts

Hurricane Michael Credit: NOAA

Estimated Agriculture Impact of Hurricane MichaelOctober 10, 2018 will be a date that farmers and ranchers in the Central Panhandle of Florida will never forget as long as they live.  Hurricane Michael landed in Bay County with 155 mph winds (Category 5 = 157 mph), the most powerful winds since Hurricane Andrew in 1992, ripped through a mostly rural area of Florida that received immediate media attention for extensive damage to the coastal communities in Bay County.  What was not made as known was the extensive damage this storm caused to agricultural operations that are a critical part of the economy of the rural counties along the I-10 corridor and into Southwest Georgia.

Typically a hurricane weakens soon after it comes ashore, but this storm had measured wind speeds of 115 mph all the way up into Donalsonville, Georgia.  This area of Florida and Southwest Georgia has been spared from major hurricanes since the 1850s, so huge, 50-150 year-old trees were snapped off, twisted, or blown over onto homes, barns, fences, grain bins and other structures.  So even structures that could withstand the winds were crushed by huge trees.

The Florida Department of Agriculture and Consumer Services (FDACS), UF/IFAS Food and Resource Economics Department, Florida Forest Service, and the National Agriculture Statistics Service, and Dr. Sergio Alvarez, University of Central Florida compiled a summary of estimated damages and loses to farms and ranches in the Florida Panhandle due to Hurricane Micheal.

Timber is a major industry in this part of the state and took the biggest hit with an estimated $1.3 billion loss.

Timber destroyed

Timber destroyed on a farm in Jackson County. Credit: Doug Mayo UF/IFAS

Cotton was virtually unharvested when the storm hit and was mostly destroyed.  What had promised to be one of the best cotton crops ever, was either blown off the plants, or the whole plant was flattened and will be nearly impossible to harvest.

Cotton blown off by storm

Jackson County cotton on the left was defoliated and ready for harvest, but was blown off by the storm. To the right a small section that had been harvested and was averaging 1900 lbs./acre. Credit: Doug Mayo, UF/IFAS

Immature cotton flattend by hurricane winds

Cotton that was still immature with closed bolls was flattend by the torrential winds in Jackson Cunty. Credit: Doug Mayo, UF/IFAS

Cattle ranches had miles of fences damage.  Many ranches utilized fence rows for pasture shade, but these trees blew over and took fences out leaving gaping holes that could not be repaired without using heavy equipment to remove the downed trees.  Volunteers from the Florida Cattlemen’s Association spent three weeks in the area to help local producers get highway fences patched to keep cattle from wandering on to highways.

Florida Cattlemens Assocaiton sent volunteers who brought heavy equipment to help local ranchers patch gaping holes caused by downed trees in Jackson County. Credit: Dough Mayo, UF/IFAS

Center pivot irrigation systems, equipment barns, hay barns and grain bins that were not built to withstand category 3 hurricane winds were mangled, damaged or destroyed.

Center Pivot destoryed in Jackson County

Center Pivot destroyed in Jackson County. Credit: Doug Mayo, UF/IFAS


Equipment barn destroyed in Jackson County

Equipment barn destroyed by Hurricane Michael in Jackson County. Credit: Doug Mayo


Jackson County hay barn destroyed by Hurricane Michael

Jackson County hay barn destroyed by Hurricane Michael. Creidt; Doug Mayo, UF/IFAS

These are just a few of the tragic images from a devastating hurricane.  The following chart shares the estimates made by a team of UF/IFAS County Agents who interviewed farmers in Jackson County in October to develop damage estimates to this major agricultural county.

Ag Damage Estiamtes from Hurricane Michael in Jackson County

Source: UF/IFAS Damage Assessment Team


In the end it will take months just to get all of the debris pilled up to burn, and years to recover from the lost income, and to repair or replace damaged or destroyed fences, center pivots, barns, and homes lost in a matter of four hours.  While USDA does have disaster programs to assist with hurricane damaged fences, debris removal, lost livestock, and timber replanting, the only hope for restoring some portion of the lost income needed to keep farm business going is action by Congress similar to the WHIP Program developed for areas impacted by Hurricanes Harvey and Irma.  But this previous program did not cover timber losses. It will be essential for local farmers to utilize agricultural organizations such as Florida Farm Bureau, Florida Cattlemen’s Association and the Florida Forestry Association to work with federal representatives to get help for producers in this region that also includes timber losses.  Otherwise many farm businesses in the Panhandle may never fully recover from this devastating storm.

Read the FDACS and Georgia storm damage reports:
FDACS Hurricane Michael Agriculture Damage Assessment Report

Facing the Storm (Hurricane Michael impact on Georgia farms)


Gadsden Tomato Forum – December 6

Gadsden Tomato Forum – December 6

Freshly picked tomatoes

Freshly picked tomatoes. Credit: UF/IFAS Photo by Tyler Jones

The annual Tomato Forum will be held in Gadsden County on Thursday, December 6, 2018.  The event will be hosted by the North Florida Research and Education Center in Quincy, Florida from 8:00 AM to 12:00 PM eastern time.

Topics to be covered will include tomato variety selection, recommended production practices, pest and disease management, and best management practices for water quality protection. Pesticide CEUs will also be provided for restricted pesticide applicators who attend this event.  The annual meeting of the Gadsden County Tomato Growers Association will be held immediately following a sponsored lunch.

Meeting Agenda (All Times Eastern)

  • 8:00 AM     Registration and coffee
  • 8:15     Opening remarks – Dr. Glen Aiken – NFREC Center Director
  • 8:30     Update on Tomato Varieties and Soil-borne Pest Management Strategies – Dr. Josh Freeman, UF NFREC
  • 9:00     Update on Tomato Diseases Management for 2019 Planning – Dr. Mathews Paret, UF NFREC
  • 9:30     Use of Soil Moisture Probes for Irrigation Scheduling Rad Yager – Certified Ag Resources, Camilla, GA
  • 10:00   Break
  • 10:15   Pest Management Updates in Tomatoes – Dr. Xavier Martini, UF NFREC
  • 10:45   Cover Crops for Tomato and Vegetable Production – Dr. Cheryl Mackowiak, UF NFREC
  • 11:15   Drone Research on Melon Disease Assessment Dr. Melanie Kalischuk, UF NFREC Research Associate
  • 11:30   Continuous Water Tracking for Optimum Crop Productivity – Doug Crawford – BMP Logic, Inc.
  • 11:45   BMP’s and Available Cost Share for Producers – Dr. Andrea Albertin – UF Regional Specialized Water Agent
  • 12:00 PM  Q&A and Sponsors Presentation
  • 12:15   Lunch
  • 1:00   Annual meeting of Gadsden Tomato Growers

The meeting location address is:

North Florida Research and Education Center (Quincy)
155 Research Road,
Quincy, FL  32351

For more information, contact:
Shep Eubanks