Potential Impact of Neonicotinoid Insecticides on Honey Bees in

Muskmelon ProductionKira Nixon

Advisor: Dr. Rick FosterPurdue University

Photo credit John Obermeyer, Purdue University

Honey Bee Importance

• $17 billion pollination, United States, 2009• Rented for pollination, cucurbits

Photo credit John Obermeyer, Purdue University

Honey Bee Population Decline

• Reasons for losses:– Pesticides– Parasites– Pathogens– Habitat loss– Nutritional Stress

Honey Bee Population Decline

• Reasons for losses:– Pesticides– Parasites– Pathogens– Habitat loss– Nutritional Stress

Neonicotinoids

• Bind to the nicotinic acetylcholine receptors in the central nervous system

• Effective against sucking and chewing insects• Fastest growing class of insecticides

– Human safety: greater than 100 times more selective to insects – replacing organophosphates, carbamates, and pyrethroids

– Many crops and multiple application methods– Highly Systemic – ability to move throughout plant– Long residual activity

Neonicotinoids on Cucurbits

– Control of striped cucumber beetle (SCB), aphids, leafhoppers, mites

– SCB vector pathogen that causes bacterial wilt– Imidacloprid, thiamethoxam, acetamiprid– Indiana $12,698,000 – 4th highest state in

muskmelon production

Photo credit Dan Egel, Purdue University

Photo credit John Obermeyer, Purdue University

Problem• Neonicotinoids are toxic to honey bees

– Lethal effects– Sublethal effects

• Altered behavior, decreased learning ability and memory, lack of coordination, inability to return home

• Systemic and Long Residual Activity– good for control, bad for pollinators

Photo credit John Obermeyer, Purdue University

Project Objectives:1. Determine the potential impact of neonicotinoid residues on

honey bees in muskmelon production– Determine residue concentrations of several recommended neonicotinoids

in muskmelon pollen.– Couple field residue concentrations with known honey bee toxicological

sensitivity.2. Determine the extent and duration of striped cucumber

beetle control among treatments.

Ultimate Goal:Modify our neonicotinoid product and application method recommendations to growers to maximize insecticide efficacy while minimizing honey bee health risks.

Materials and Methods• 2013 and 2014 Meigs Farm

– Throckmorton Purdue Agricultural Center, Lafayette, IN

• Muskmelon – variety ‘Athena’• Growing Conditions:

• Plant April 17th greenhouse bedding trays• Transplant into field mid-May • Black plastic mulch• Drip irrigation

TreatmentsNeonicotinoid Trade Name Application Method

UntreatedImidacloprid Admire Pro Soil Drench - Greenhouse/TransplantingThiamethoxam FarMore Seed TreatmentThiamethoxam Platinum Soil Drench - TransplantingThiamethoxam Actara Foliar Spray - MidseasonAcetamiprid Assail Foliar Spray - Midseason

2013 Untreated Plants

Photo credit John Obermeyer, Purdue University

Flower Collection

• Flowers collected 6am-10am– June 27th 2013, July 10th 2014

• ~34,500 combined 2-year total

Chemical Analysis

• Imidacloprid• Thiamethoxam

– Clothianidin

• Acetamiprid

RESULTSPollen Residue Concentration

RESULTSImidacloprid

1.81

86.5896.08

Admire Pro Admire Pro

48 ng/g:Increased mortality, disrupted olfactory learning senses, decreased feeding, mobility, and mid-term memory (Decourtye et al., 2003, 2004a, 2004b; Guez et al., 2001; Lambin et al., 2001; Suchail et al., 2001; Teeters et al., 2012)

0.05

1.49

3.31

Admire Pro Admire Pro

1 ng/g:Increased mortality, disrupted olfactory learning senses, (Guez et al., 2001; Suchail et al., 2001)

Imidacloprid(Admire ProTM)

• Potential to negatively impact honey bees– Increased mortality, disrupted olfactory learning senses,

decreased feeding, mobility, and mid-term memory (Decourtye et el., 2004, 2004a, 2004b; Guez et al., 2001, 2003, Lambin et al., 2001; Suchail et al., 2001, Teeters et al., 2012)

RESULTSThiamethoxam

0.29

76.32

0.64

64.24

Platinum Actara FarMore

67 ng/g:Reduced number of bees able to return to hive (Henry et al., 2012)

0.24 3.75

132.75

9.251.98 1.75

86.40

Platinum Actara FarMore

67 ng/g:Reduced number of bees able to return to hive (Henry et al., 2012)

100 ng/g:Increased mortality (Laurino et al., 2011)

0.160.72

6.25

1.38

5.14

6.48

3.87

Platinum Actara FarMore

2.1 ng/g:Decreased adult worker populations when combined with 5.3 ppb thiamethoxam (Sandrocket al., 2014)

Thiamethoxam Clothianidin

(FarMore®, Platinum®, Actara®)• FarMore®

– Potential to negatively impact honey bees• Decreased adult worker populations (Sandrock et al., 2014)

• Platinum®

– Potential to negatively impact honey bees• Reduce foragers’ ability to return to their hive (Henry et al.,

2012)• Actara®

– Potential to negatively impact honey bees• Reduce foragers’ ability to return to their hive, increase

mortality, decrease adult worker populations (Henry et al., 2012; Sandrock et al., 2014)

RESULTSAcetamiprid

150.43

0.35

1000 ng/g:Reduced learning performance (Hassani et al., 2008)

Assail

82.77

2.60

Assail

1000 ng/g:Reduced learning performance (Hassani et al., 2008)

Acetamiprid(Assail®)

• No known negative impacts

RESULTSStriped Cucumber Beetle (SCB)

Control

Economic threshold1 SCB per plant

½ Rate SevinMay 29 and June 6

Economic threshold1 SCB per plant

½ Rate SevinMay 29 and June 6

Economic threshold1 SCB per plant

July 7, Foliar Application

Economic threshold1 SCB per plant

½ Rate SevinMay 29 and June 6

Striped Cucumber Beetle Control

• FarMore®

– No protection against beetles

• Admire ProTM and Platinum® (low and high rates)

– Maintain populations below threshold 20 days

• Actara® and Assail® (high label rate only)

– Maintain populations below threshold 7 days

Ultimate Goal

Modify neonicotinoid product and application method recommendations to growers to maximize insecticide efficacy while minimizing honey bee health risks.

Putting it all Together

• FarMore® (thiamethoxam)– Potential negative impacts– No control

• Admire ProTM, Platinum® (imidacloprid, thiamethoxam)– Both potential negative effects– Low rate– 20 days of control

• Assail®, Actara® (acetamiprid, thiamethoxam)– Actara potential negative effects– Assail no known negative effects– High rate– 7 days of control

A Special Thanks• Dr. Rick Foster• Dr. Christian Krupke, Dr. Steve Weller• Lab mates

– Ahmad Mohammadi, Fawsia Mumtaz, Cal Spigler, Tanvi Lad, Samuel Escobar, Elmer Marquez, Jose Aguilar

• Larry Bledsoe and lab crew• John Obermeyer• Amber Jannasch

• Ostermeyer Endowment• Indiana Vegetable Growers Association

Questions?

Kira Nixonklalbrig@purdue.edu