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Research Connections

Research Connections


Listronotus sp., an Emerging Weevil Pest of Celery and Parsley in Southern Florida

Anna Mezaros 

Julien Beuzelin 

Anna Mészáros
Commercial Vegetable Agent
Dr. Julien Beuzelin

(561) 233-1759
(561) 993-1559

Anna Mészáros of the UF/IFAS Palm Beach County Extension office and Dr. Julien Beuzelin of the UF/IFAS Everglades Research and Education Center recently began investigating the increase in unusual insect injury observed since 2020 in conventional and organic celery and parsley fields in southern Florida. This injury consisted of weevil larval tunneling through plant petioles, crowns, and roots. A research and extension program was initiated to identify the insect causing the injury, study pest population dynamics, evaluate insecticide efficacy, and promote information exchange to answer grower needs.

  • The weevil adults infesting celery plants were identified as Listronotus sparsus, a relatively widespread species that was not previously reported as a crop pest.
  • This weevil exhibits behavior comparable to carrot weevils, L. oregonensis and L. texanus, which are serious pests of Apiaceae crops in the Great Lakes region and Texas, respectively. Thus, this weevil might represent a significant threat to celery, parsley, dill, cilantro, and carrot production in Florida.
  • In celery, most of the weevil damage is at the base of the petioles, especially in the outer petioles; tunnels can be as long as four inches from the base of the plant going up through the petiole. Weevils can also feed on the crowns of celery plants. In parsley plants the petioles are thinner than in celery plants, therefore weevils tend to feed more on the base of the plant and the roots.
  • Observations suggest that the weevil infests plants throughout the crop season and has multiple overlapping generations per year.
  • Based on grower commercial practices and our experiments, Vydate is currently recommended for weevil management in celery, however, this insecticide is not registered for use in parsley. Exirel and Diamond might have activity against the weevil. However, while Exirel is registered for use on celery and parsley, Diamond is not registered on either crop. Thus, there is a need for additional studies evaluating insecticides, including Exirel and Diamond, which showed promising results in Canada for L. oregonensis control. These studies might lead to new insecticide registrations and updated L. sparsus management recommendations.

We are thankful for our great collaborations with Florida celery and parsley growers and crop consultants who have shared their knowledge and have assisted with on-farm experiments to develop a management solution for L. sparsus.

If you suspect an L. sparsus infestation in your field, please contact Julien Beuzelin,, or Anna Meszaros,

For more information on L. sparsus, including details on feeding symptoms and management research, visit this page.



Listronotus sparsus adults 

 Listronotus sparsus adults



Listronotus sparsus larva at the base of a celery petiole 

Larva at the base of a celery petiole


Past Research Connections


10/18/2022 Expansion of the Florida Soil Moisture Sensor Network
Dr. Vivek Sharma "Dr. Vivek Sharma leads the Florida statewide soil moisture sensor (SMS) network. This advanced technology is free to growers and enables more informed irrigation management decisions- allowing for the conservation of water, with associated cost-savings, and enhancing crop water and nutrient use efficiency. Water quality is also improved through the reduction of runoff and leaching events. Enrollment open- see article for details."
Dr. Vivek Sharma
Precision Water Management
Agricultural Engineering
(352) 294-6725
Keywords: soil moisture sensor, cost-savings, irrigation management, technology, agricultural engineering
4/26/2022 Nutrient Management Research
Sanjay Shukla Shinsuke Agehara "Dr. Shukla, Dr. Agehara, and their interdisciplinary team are carrying out research to evaluate current Mehlich-3 phosphorous recommendations for various vegetable crops. The team's research is also addressing Senate Bill 1000 by assessing the need for site-specific recommendations."
Dr. Sanjay Shukla
Agricultural Engineering
Dr. Shinsuke Agehara
(239) 658-3425
(813) 419-6583
Keywords: phosphorous, nutrient management, tomato, potato, bean, legislative funding, SB 1000
4/07/2022 Integrated Pest and Disease Management in Vegetable Crops
Shouan Zhang "Dr. Zhang and his team evaluate novel non-fumigant control measures against southern root-knot nematode and Fusarium oxysporum with studies conducted in China and Homestead, FL."
Dr. Shouan Zhang
Vegetable Plant Pathology
(786) 217-9233
Keywords: southern root-knot nematode, Fusarium oxysporum, Fluopimomide, abamectin, fludioxonil, fluazaindolizine, cucumber, tomato, squash
3/15/2022 Diamide Insecticide Resistance in Diamondback Moth
Hugh Smith "Diamondback moth (DBM) has multiple mechanisms of insecticide resistance resulting in at least 95 different insecticides that have been documented to fail at control. Dr. Smith’s team tested resistance to diamides- a relatively new group of insecticides- and found that 90% of a DBM population from Manatee County, FL had genes associated with resistance to chlorantraniliprole (Coragen), with an LC50 that was 2,845 times the susceptible control. The population also had resistance to cyantraniliprole (Exirel), with an LC50 that was 108 times the susceptible control."
Dr. Hugh Smith
(813) 419-6588
Keywords: diamondback moth, chlorantraniliprole, cyantraniliprole, diamides, insecticide resistance, crucifers
2/22/2022 Low-Cost, Smart Technology for Input Management Utilizing AI
Yiannis Ampatzidis "Dr. Ampatzidis’s lab recently developed and evaluated a preliminary prototype of a low-cost, smart herbicide sprayer. For under $1,500, the sprayer used a AI-based machine vision software to distinguish between the crop and target weeds. In artificial situations, it had the ability to detect 100% of target weeds and accurately spray 91-95% of the target weeds. In field situations, target weed detection was reduced to 85% while spray precision was reduced to 71%. Another sprayer developed for citrus tree crops varied the amount of insecticide sprayed for each tree based on height, leaf density, and fruit count, and was estimated to reduce chemical use by about 30% compared to traditional spray methods."
Dr. Yiannis Ampatzidis
Precision Agriculture Engineering
(239) 658-3451
Keywords: AI-based herbicide sprayer, tomato crops, citrus crops
1/11/2022 Brown Marmorated Stink Bugs (BMSB) in Florida Tomatoes
Amanda Hodges "Dr. Amanda Hodges led this regional stinkbug surveying effort to understand species mix and population levels throughout the spring growing season. BMSB was identified in three new Florida counties- Manatee, Hendry and Lee."
Dr. Amanda Hodges
Entomology and Nematology
(239) 658-3451
Keywords: Brown Marmorated Stink Bugs, Halyomorpha halys, population survey
12/20/2021 The Distribution and Management of Meloidogyne enterolobii
Johan Desaeger "A regional survey and research effort to better understand and manage Guava Root Knot Nematode in vegetable crops in the Southeast that is being led by Dr. Desaeger in conjunction with Nematologist Dr. Zane Grabau and Agricultural Economist Dr. Zhengfei Guan. "
Dr. Johan Desaeger
(813) 419-6592
Keywords: Guava Root Knot Nematode, resistant vegetable germplasm, nematicide efficacy, cover crops and crop rotation efficacy, genetic variability and distribution, sweet potato, cucumber, watermelon, tomato
11/09/2021 Kaolin and Limonene for Whitefly Control in Vegetable Crops
Xavier Martini "Dr. Martini is investigating utilizing Kaolin clay (Surround®), a contact repellent, and essential oil limonene, a distance repellent, to keep whiteflies out of susceptible crops. Individually, Kaolin and limonene slightly reduced whitefly populations on tomato. Results demonstrated an additive effect when applying both Kaolin and limonene. The efficacy of Kaolin + limonene was highest during dry conditions. During field trials, the greatest reduction was observed when alternating the grower’s weekly insecticide program with weekly applications of Kaolin and limonene"
Dr. Xavier Martini
(850) 875-7160
Keywords: whitefly, Bemisia tabaci, Kaolin and limonene efficacy, tomato
10/12/2021 Update on Cucurbit Downy Mildew Management
Gary Vallad "Gary Vallad’s team compared efficacy and efficacy duration of 11 different insecticides against cucurbit downy mildew across 3 Florida field trials. Dimethomorph, fluopicolide, and cymoxanil were much less effective than other active ingredients, which confirms reports from other states of resistance to these chemistries. Some insecticides that had low efficacy with infrequent application periods (such as chlorothalonil) had results comparable to more effective active ingredients with weekly applications."
Dr. Gary Vallad
Plant Pathology
(813) 419-6577
Keywords: cucurbit downy mildew, fungicide efficacy, duration of field activity, cucurbit crops
9/21/2021 Asian Bean Thrips Research Continues
Hugh Smith "Surveying and blue sticky trap monitoring of asian bean thrips on bean crops in Hendry County showed that populations exist year-round, but not do not increase during the summer on weed hosts and decrease soon after crops are terminated. Insecticide efficacy research indicated that methomyl (Lannate), spinetoram (Radiant), acetamiprid (Assail), Abamectin (Agri-Mek), and cyantraniliprole (Exirel) were most effective against adults under laboratory conditions. Pyrethroids were not effective. In larvae, spirotetramat (Movento) and novaluron (Rimon) caused the highest mortality."
Dr. Hugh Smith
(813) 419-6588
Keywords: asian bean thrips, Megalurothrips usitatus, surveying, insecticide efficacy, snap beans
2/02/2021 Sulfur Amendments to Lower pH in Southwest Florida
Phillip Williams "This was a preliminary experiment to compare the pH lowering effectiveness of two elemental sulfur (S) soil amendment application methods, granular and water dispersible. The granular S experiment lasted for eight weeks with no change in soil pH for any of the rates tested. The water-dispersible S applied treatments were conducted in two 4-week intervals. Drastic pH reductions were observed in both four-week tests in all treatments, however, it was most significant in the higher rates."
Dr. Phillip Williams
Vegetable Horticulture
(239) 658 - 3410
Keywords: sulfur, soil chemistry, pH levels