Diaprepes%20Root%20Weevil%20and%20Other%20Pests%20of%20Regulatory%20Concern

1
Diaprepes Root Weevil and Other Pests of
Regulatory Concern
Catharine Mannion University of Florida, IFAS,
Tropical Research and Education Center
2
Diaprepes Root Weevil

• Native of the Caribbean Islands
• Sugarcane rootstalk borer, Apopka weevil, citrus
  root weevil

• First reported in Florida in 1964 in a nursery in
  Central Florida
• Major pest of citrus, sugarcane, ornamentals,
  root crops

3
Diaprepes Root Weevil on Ornamentals

• Little information on the effect of adult and/or
  larval feeding on ornamental plants
• Many ornamental plants can support advanced
  larval injury before external symptoms (leaf
  yellowing, defoliation, wilting) are observed
• Some ornamental plants such as oaks appear to be
  susceptible to root diseases such as Phytophthora
  root rot following larval feeding
• Most of the research focus has been in citrus

4
Feeding Damage by Adult Weevils

• Adults feed on the foliage of numerous plants
  causing a typical notching on the leaf margins
• Adults can be found year round in southern
  Florida with peak flights in the spring and fall

5
Oviposition

• Females lay their eggs between two
  leaves or fold a single leaf

• 30 264 eggs per mass (approximately 5,000 eggs
  in a lifetime)
• Neonates hatch and fall to the soil surface
• Neonates are very active and begin moving into
  the soil where they feed on plant roots but can
  survive for numerous days without feeding

6
Larvae can cause severe damage to roots
ultimately killing the plant
7
Preliminary Plant Host Survey for Egg Masses,
Damage, or Adults in a Field Nursery -
(September 1998)

• Ti (Cordyline terminalis)
• Dahoon holly (Ilex cassine)
• Silver trumpet tree (Tabebuia caraiba)
• Jacaranda (Jacaranda mimosifolia)
• Geiger tree (Cordia sebestena)
• Gumbo limbo (Bursera simaruba)
• Cocoplum (Chrysobalanus icaco)
• Silver and green buttonwood (Conocarpus erectus)
• Black olive (Bucida buseras)
• Live oak (Quercus virginiana)

• Brazilian beauty leaf (Calophyllum braziliense)
• Autograph tree (Clusia rosea)
• Bauhinia sp.
• Cassia sp.
• Crape myrtle (Lagerstroemia sp.)
• Mahogany (Swietenia mahogani)
• Privet (Ligustrum sp.)
• Coconut palm (Cocos nucifera)
• Pygmy date palm (Phoenix roebellini)
• Satin leaf (Chrysophyllum olivivorme)

8
Risk of Movement

• Adults are fairly strong fliers, but most
  widespread distribution is attributed to movement
  of plant material
• Immature stages in soil or containers of nursery
  plants
• Egg masses on foliage
• Neonate larvae are active and can survive for
  numerous days without feeding
• Adults on foliage
• Although adults are large and somewhat obvious,
  they can hide
• Movement of adults in trucks or equipment

9
Texas Shipping Requirements

• All nursery stock not grown in a greenhouse must
  be sprayed for adults with an approved
  insecticide within 14 days of movement
• The soil must be drenched with bifenthrin or have
  bifenthrin incorporated in the mix.
• Soil incorporation for fire ants meets the
  required levels for Diaprepes, however, if the
  plants are older than 6 months, another treatment
  will be necessary
• Soil drench the high drench rate for fire ant
  meets the required levels for Diaprepes (25ppm)

10
Approved Insecticides for Foliar Sprays

• Talstar (bifenthrin)
• Orthene (acephate)
• Sevin (carbaryl)
• Dursban (chlorpyrifos)

11
Texas Diaprepes Quarantine
Infested Counties April 2001
12
Establishment in Container Ornamentals

• Isolated populations
• Ability to establish
• External factors

13
Larval Establishment in Container Ornamentals
14
Larval Establishment in Container Ornamentals

• 0 egg masses
• 5 egg masses
• 20 egg masses

15
Larval Establishment in Container Ornamentals
Treatment Total Larvae Recovered Percent Larval Establishment
Talstar 0 eggs 0 0
Talstar 400 eggs 0 0
Talstar 1300 eggs 0 0
Control 0 eggs 0 0
Control 400 eggs 1 1.0
Control 1300 eggs 4 0.3
16
Percent Reduction of Diaprepes Larvae in 1-Gallon
Containers Drenched with Talstar(7 DAT)
Treatment Percent Reduction
9th instar (65 days old) 47.6
8th instar (51 days old) 80.0
7th instar (41 days old) 82.4
17
Soil Removal

• Location Commercial nursery, Broward County
• Host Plant Ficus alli
• 45 gallon container
• Diaprepes Natural infestation
• Treatments (7 replications)
• 1. Field soil
• 2. Potting mix
• 3. Potting mix Talstar _at_ 25 ppm
• Evaluation 5 weeks after treatment

The trees were removed from the field and placed
in 45 gallon containers. In treatments 2 and 3,
the field soil was removed and replaced with
potting mix. The Talstar drench was applied in 9
gallons per container.
18
The Effect of Soil Removal and Bifenthrin on
Natural Populations of Diaprepes abbreviatus
19
Talstar Nematodes 3 tests

• Location Commercial nursery or the research
  center Diaprepes Artificially infested
• Treatments Interaction of entomopathogenic
  nematodes and Talstar

Test 1 - 45-gallon containers
Test 3 8-ounce containers
Test 2 3-gallon containers
20
Test 1 - Methods

• Location Commercial nursery, Broward County
• Host Plant Bucida buceras (big leaf black
  olive), 45 gallon container
• Diaprepes Artificially infested
• Treatments (7 replications)
• 1. Talstar _at_ 25 ppm
• 2. Heterorhabditis indica _at_ 9.8 billion/A
• 3. Talstar _at_ 25 ppm H. indica _at_ 9.8
  billion/A
• 4. Control
• Evaluation 5 weeks after treatment

The trees were potted in 45 gallon containers
with a potting media. Each container was
infested with 15-fifth and ninth instar Diaprepes
(approximately half of each age in each
container). One week after infestation,
treatments were applied. Talstar was drenched in
9 gallons per container. Nematodes were applied
in approximately 2 gallons per container.
21
The Effect of Bifenthrin and Heterorhabditis
indica on Diaprepes abbreviatus
22
Test 2 - Methods

• Location Tropical Research and Education
  Center, Homestead
• Host Plant Conocarpus erecta (buttonwood),
  3 gallon containers
• Diaprepes Artificially infested
• Treatments Next slide
• Evaluation 2 weeks after treatment

Five larvae were buried in each container with
potting mix and one plant. Ten days after the
larvae were added to the containers, treatments
were applied. Insecticides were drenched with
0.53 gallons per container. Nematodes were
applied in 25.5 oz. per container.
23
Test 2Treatments (5 replications)
1. Talstar _at_ 25 ppm 5th instar 2. Talstar
_at_ 25 ppm 7th instar 3. Talstar _at_ 25 ppm
9th instar 4. H. indica _at_ 2 billion/A 5th
instar 5. H. indica _at_ 2 billion/A 7th
instar 6. H. indica _at_ 2 billion/A 9th
instar 7. Talstar _at_ 25 ppm H. indica _at_ 2
billion/A 5th instar 8. Talstar _at_ 25 ppm
H. indica _at_ 2 billion/A 7th instar 9.
Talstar _at_ 25 ppm H. indica _at_ 2 billion/A 9th
instar 10. Flagship (thiomethoxam) _at_ 17 oz/A
5th instar 11. Flagship _at_ 17 oz./A 7th
instar 12. Flagship _at_ 17 oz./A 9th
instar 13. Control 5th instar 14. Control
7th instar 15. Control 9th instar
24
The Effect of Bifenthrin and Heterorhabditis
indica on Diaprepes abbreviatus
25
Test 3 - Methods

• Location Tropical Research and Education
  Center, Homestead
• Host Plant None (carrot provided for food)
• 8 oz. plastic cups
• Diaprepes Artificially infested
• Treatments Next slide
• Evaluation 2, 3, 4, 5, and 6 days after
  application

Diaprepes larvae (9th instar) were placed in cups
containing potting media and one carrot for food.
Nematode and chemical applications were made 4
days after larvae were placed in the cups.
26
Test 3 - Treatments
Nematode Heterorhabditis indica and Steinernema
riobravis (low rate 1 billion/A
high rate 2 billion/A) Chemical Talstar
(bifenthrin) (low rate 12.5 ppm
high rate 25 ppm)

• Nema-low Talstar-low
• Nema-low Talstar-high
• Nema-high Talstar-low
• Nema-high Talstar-high
• Control

• Nema low
• Nema-high
• Talstar low
• Talstar high

27
Talstar Heterorhabditis indica (Grubstake)
28
Talstar Heterorhabditis indica (Grubstake)
29
Talstar Heterorhabditis indica (Grubstake)
30
Talstar Heterorhabditis indica (Grubstake)
31
Talstar Heterorhabditis indica (Grubstake)
32
Talstar Steinernema riobravis (BioVector)
33
Talstar Steinernema riobravis (BioVector)
34
Talstar Steinernema riobravis (BioVector)
35
Talstar Steinernema riobravis (BioVector)
36
Talstar Steinernema riobravis (BioVector)
37
Summary

• Strikingly similar results were obtained in all
  tests
• In all cases, the combination treatment of
  Talstar and nematode provided the best control
  suggesting a synergy or additive effect between
  treatments.
• The addition of nematodes may provide a way to
  reduce the amount of insecticide currently
  recommended.

38
Required Soil Treatment

• Incorporated Talstar for fire ant meets the
  requirement
• If it has been more than 6 months, a drench is
  necessary
• Drench high drench rate for fire ants
• Rate is based on bulk density of planting media

39
Insect Pests of Concern in South Florida

• Pink hibiscus mealybug
• Stellate scale
• Cycad aulacaspis scale
• Holopothrips
• Myllocerus weevil
• Lobate lac scale

40
Pink Hibiscus Mealybug
Photos by UF, Osborne
41
Stellate Scale (Vinsonia stellifera)

• Female is star-shaped and soft-bodied, 3/8 inch
• Introduced into Florida from Puerto Rico in the
  1950s but was eradicated
• Found in July 2002 at numerous sites
• Hosts Numerous ornamental plants and fruit
  trees, coffee

Hunsberger
Hunsberger
42
Cycad aulacaspis scaleAulacaspis yasumatsui
D. Caldwell

• Pest of cycads of the Cycas sp.
• Found in Miami, Florida in 1996
• Spreading northward in the state
• Threatened rare and endangered species of cycads

43
Holopothrips near inquilinus

• Found in 2001 on trumpet trees, Tabebuia spp.
• This insect is new to the United States
• From a group of thrips
• that are foliage feeders
• with some reported to
• cause galls.
• Currently in Miami-Dade,
• Broward and Palm Beach
• Counties.

44
Myllocerus undatus

• Broward and northern Miami-Dade County
• From Sri Lanka
• Little information known about this species
• It likely has a very large host range including
  fruit and ornamentals

45
Lobate Lac ScaleParatachardina lobata lobata

• First collected in Florida in August 1999 May
  become a pest on several tropical and subtropical
  fruits and ornamentals
• Native to India and Sri Lanka
• Currently in Palm Beach, Broward and Miami-Dade
  Counties

46
Lobate Lac Scale

• More than 100 species of woody plants have been
  determined to be hosts
• Thirty-two are native plants
• Some of the plants include hibiscus, cocoplum,
  black olive, weeping fig, buttonwood, sand live
  oak, and wax myrtle

47
Lobate Lac Scale

• The adult female has two pairs of prominent
  lobes dark reddish brown

• Crawlers are elongate-oval deep red and mobile

Small hole
48
(No Transcript)
49
Catharine Mannion Research and Extension
Specialist Ornamental Entomology University of
Florida, IFAS Tropical Research and Education
Center 18905 SW 280th Street Homestead, FL
33031 305-246-7000 cmannion_at_mail.ifas.ufl.edu
50
Photo Credits

• Myllocerus undatas photos are property of
  Department of Agriculture and Consumer Services
  (DOACS).
• All other photos are property of Catherine
  Mannion.