Update on Bud Mites, Blueberry Gall Midge & Chilli Thrips

Oscar E. Liburd

Professor of Small Fruits and Vegetable Entomology

University of Florida

Gainesville, FL 32611

Blueberry bud mite (BBM)

• Eriophyid mite

• 2 pairs of legs close to the head

• Microscopic (200 μm)

• Tapers toward the dorsal part of

the abdomen

• Transparent /colorless to whitish

• Attack primarily Vaccinium spp.

Life History & Description • Mites overwinter under bud scales or in protected sites

near the host plant

• Adults emerge at bud break during spring

• Eggs, Protonymphs, Deutonymphs, & Adults

• A female can lay up to 200 eggs during its lifetime.

• In north-central Florida population peaks around February-March

Symptoms of BBM Infestations

• Swollen bud scales

• Buds appear reddened &

rosetted

• Reduced fruit set

Symptoms of BBM Infestations Cont’d

Evaluation of Post-harvest Acaricides for Control of BBM

• Envidor® 2 CS (Spirodiclofen)

• Agri-Mek® 1.8 EC (Abamectin)

• Thionex® 3 EC (Endosulfan)

• Water (Control)

- Southern highbush cv Farthing

- RCBD with 4 reps

-CO2 sprayer, application date Oct 14 * Observation of flower bud damage & BBM density during 2009/10 season

Effect of Acaricides on the Percentage of Flower buds Infected with BBM

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Findings and Assessment of Miticides

• All of the miticides reduced the population of BBM and the number of flower buds infected compared with the control

• Overall Endosulfan was the most effective acaricide in reducing the percentage of flower buds infected with BBM

• Envidor was the second most effective acaricide in reducing BBM infestation

• Agri-Mek performance was not significantly different to Envidor in reducing BBM infestation

Management of BBM

• Pruning and removal of older infected branches

• Post-harvest application of acaricides - Endosulfan and horticultural oils,

• Envidor was evaluated through the IR-4 program ~ 3-4 yrs ago and registration is pending.

• Endosulfan will be phased out globally 2015

• Portal (78) (fenpyroximate) is a miticide that will be going through the IR-4 program during 2014-2015 [Nichino America Inc.]

Blueberry gall midge

• Dasineura oxycoccana Johnson

• Pupae overwinter in soil

• Adult females lay eggs in developing buds

• Up to 80% yield loss

Injury resulting from blueberry gall midge

New shoot damage

Ovary necrosis & Larvae in flower bud

Monitoring for BGM

• Bucket emergence trap • Clear panel trap

Cook et al. 2011

Modified panel trap

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Mean Number of Blueberry Gall Midge per Trap & Larvae per Bud (2012)

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Captures of BGM in Bucket traps in Rabbiteye Blueberries

Between rows

Management of BGM

• Weekly monitoring of BGM population in the field

• Application of Insecticides

- Delegate (Spinetoram)

- Malathion

- Entrust (Spinosad)

• Parasitoids

• Most common genera:

- Platygaster (flower buds)

- Aprostocetus (leaf buds)

Chilli Thrips (Adult & Larvae)

Adults are about 1.2 mm (0.05) inches long

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Flower thrips

Chilli thrips

Symptoms of Chilli Thrips Infestation

• Severe leaf curling in heavy infestation

• Implicated in

transmission of a few virus diseases • Tomato Spotted

Wilt Virus (TSWV ) and Yellow Spot Virus in peanuts

Symptoms of Chilli Thrips Infestation

Bronzing

Shoot Die-back

Insecticide Management Program

• Spinosyns

Delegate 3.5

Entrust (organic) 3.0 • Neonicotinoids

Assail (Acetamiprid) 4.0

Imidacloprid (Admire) 3.5 – 4.0

• Organophosphates

Malathion 2.5 – 3.0

Imidan (Phosmet) 2.5 – 3.0

Weekly monitoring (scouting of blueberry planting)

Acknowledgements

• Florida Blueberry Growers Association

• Staff (post-Docs & Graduate Students)

• USDA-NIFA Pest Management Program

• Florida growers that allowed us to conduct research on their farms

Oscar E. Liburd http://liburd/fruitnvegipm/index.htm oeliburd@ufl.edu