Insect and Related Pests of Bromeliads. Insects and Other Invertebrates Found on Bromeliads in...
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Insect and Related Insect and Related Pests of BromeliadsPests of Bromeliads
Insects and Other Insects and Other Invertebrates Found on Invertebrates Found on Bromeliads in Florida:Bromeliads in Florida:
• Aphids• Leafminers• Thrips • Grasshoppers• Moths• Mites
• Nematodes• Snails and slugs• Mosquitoes• Scales and mealybugs • Weevils
AphidsAphids
• Soft-bodied, pear-shaped; suck plant juices
• Only rice root aphids have been reported on bromeliads in FL
UF-MREC
Rice Root Aphid Rice Root Aphid ((Rhopalosiphum Rhopalosiphum rufiabdominalisrufiabdominalis))• Dark green or orange to
reddish brown
• Reddish area in middle of back
• Lives on roots
• Causes stunting
• In Florida, one known infestation of rice root aphid in bromeliads: found on about 150 Aechmea chantinii
plants at a nursery in Apopka, March 1996
• Found on coriander in Florida (Belle Glade); in Texas, primary hosts are Prunus spp. (peaches and plums) and secondary hosts are small grains (wheat,rice)
Aphid ManagementAphid Management• Remove infested plants to prevent spread
• Encourage natural enemies: many predators, parasites and pathogens attack aphids (lady beetles, lacewing larvae, syrphid fly larvae, wasp parasites); specific natural enemies of rice
root aphid unknown
• Systemic insecticide
LeafminersLeafminersLarvae of:• flies (maggots)• moths (caterpillars)• beetles (grubs)
• Tunnel between upper and lower leaf surfaces
• Blotch or serpentine mines
LeafminersLeafminersAttack a variety of ornamental and vegetable crops
Management:• Remove infested leaves/plants• Practice good sanitation• Encourage natural enemies
ThripsThrips
• Very small, elongate
• Nymphs usually pale yellow, adults black or yellow-brown
• Winged or wingless (wings have narrow fringe of hairs)
• Populations peak during spring and summer
ThripsThrips
• Females deposit eggs in leaf slits
• Two nymphal stages, then two resting stages (prepupa and pupa)
• Period from egg to adult may be 2-4 weeks, depending on species and conditions
Thrips DamageThrips Damage
• Feed on flowers and foliage
• Puncture plant cells and suck up plant juices
• Feeding produces silvery or deformed leaves
and blotches on flowers
UF-MREC
Thrips ManagementThrips Management
• Detect presence by shaking onto white paper and looking for excrement
• Natural enemies may be effective (predatory mites, green lacewing larvae, damsel bugs, pirate bugs)
• By the time damage is noticed, thrips may have moved on
• Insecticidal soap or systemic insecticide
GrasshoppersGrasshoppersChewing insects: large holes in leaves
Life cycle: eggs laid in soil; nymphs crawl to surface; develop wing pads with successive molts; adults have fully developed wings
GrasshoppersGrasshoppers
Management:
Mechanical control (net or broom)
MothsMoths
Larvae of at least 7 small moths have been found on bromeliads in Florida, mostly on Tillandsia fasciculata.
Banana MothBanana Moth• Adults have brown wings with 2 small black spots
• Larvae have dark brown spots
• Eggs laid in plant crevices and hatch in 5-6 days, larvae take 21-26 days to develop, pupal stage lasts 13-14 days, adults live 5-7 days
• Breed all year
• Most commonly found in south Florida ornamental nurseries, especially around palms
Banana MothBanana Moth• Larvae may feed on detritus and plant stems
• Attack damaged
plant tissue, then move to healthy tissue nearby
• Debris and excrement can be seen on outside of plants
Bromeliad Pod Borer Bromeliad Pod Borer ((Epimorius Epimorius
testaceellustestaceellus))
• Adult moth is brown with tan on wings (front wings darker)
• Males have more red-brown on wings
Bromeliad Pod BorerBromeliad Pod Borer
• Feeds on and damages flower pods of Tillandsia fasciculata
• Not common but may be a localized severe pest
• Spins cocoon to pupate within excavated flower pod
• Occurs most frequently in March - May (main flowering period of T. fasciculata)
Management of Moths Management of Moths on Bromeliadson Bromeliads
• Presence can be detected by discolored flowers, insect excrement on flower capsules
• Wasp parasitoid (Eurytoma aerflora) may prevent outbreaks (Glades and Miami-Dade Counties)
• Bacillus thuringiensis (B.t.)
MitesMites• Related to spiders and ticks
• Adults have 8 legs
• Puncture leaf and suck out plant juices
• Spider mites are occasional bromeliad pests (pineapple mite
on Aechmea)
MitesMites• Adult female lays several hundred eggs
• Eggs hatch in about 3 days
• 3 molts
• Can complete development from egg to adult in 7-10 days
• Lower leaf surfaces often have fine silken webbing across them
UF-MREC
Mite ManagementMite Management
• Look for mites, eggs, cast skins
• Not all mites are harmful
• Insecticidal soap
NematodesNematodes
• Unsegmented roundworms
• Most are microscopic
• Most feed on bacteria, fungi and other microorganisms
• Most that attack plants feed externally on the root, internally within the root, or internally within foliage
Reniform Nematode Reniform Nematode ((Rotylenchus Rotylenchus reniformisreniformis) )
• Hosts include pineapple and many ornamental plants
• Found where soils have high silt or clay content (Miami-Dade County, Panhandle)
• Feed partially inside roots (female head region embedded)
• Symptoms appear like those of nutrient deficiencies or drought stress (yellowing, wilting, stunting, death)
Tylenchocriconema Tylenchocriconema allenialleni
Adult T. alleni
• Has been found twice on Tillandsia flabellata from Guatemala
• Has not been seen in Florida
• Bromeliads originating from Central America should be inspected
Tylenchocriconema Tylenchocriconema allenialleni
• Feeds outside the leaf, piercing leaf cells with stylet (mouthparts)
• Found in plant’s crown, just below waterline
T. Alleni feeding on Tillandsia flabellata leaf.
Symptoms of Infestation Symptoms of Infestation by by Tylenchocriconema Tylenchocriconema
allenialleniLight brown spots on leaves, becoming dark lesions; clusters of nematodes and eggs on dried leaves appear wool-like
Nematode ManagementNematode Management
Prevent movement to other plants:
• Remove dead leaves
• Use clean stock
• Use clean soil
• Use clean containers and leave containers on benches (don’t let
them touch the ground)
Snails and SlugsSnails and SlugsBoth are gastropods, with a head, ventral muscular foot and shell (internal in slugs, external in snails)
• Damage usually at night (resembles adult bromeliad weevils or caterpillars)
• Hide in moist, dark areas in day
• Leave silvery slime trails
• Barriers or traps can be used for slugs
UF-MREC
MosquitoesMosquitoes• Tank bromeliads serve as breeding sites for mosquitoes.
• Mosquitoes do not harm bromeliads but are a nuisance and public health threat to humans.
• Egg, larval and pupal stages are found in
water.
Michele M. Cutwa / UF
MosquitoesMosquitoes Aedes albopictus is an efficient transmitter of West Nile virus, and Culex can transmit West Nile, Eastern equine encephalitis and St. Louis encephalitis.
In south Florida, the native Wyeomyia mosquitoes take over in tank bromeliads, displacing A. albopictus. Wyeomyia are not present in north Florida.
Mosquito control in bromeliads is of greater concern in north Florida:
J.L. Castner/UF
Management of Management of Mosquitoes in Bromeliad Mosquitoes in Bromeliad
TanksTanks• Reduce organic matter in tanks (flush out debris with hose; put
plants in shadehouse or greenhouse)
• Flush out eggs with hose (1-2 X per week)
• Methoprene briquettes (Altosid): add new tablets every 1 ½ to 2 months, one in each separate water hole
ScalesScales• Very small, soft-bodied insects
• 1st instars (crawlers) are mobile but later stages
are legless, attaching themselves to the leaf
• Feed on plant juices with long stylet mouthparts
• Three largest scale families: armored scales, soft scales, mealybugs
ScalesScalesArmored scales that affect
bromeliads:
• Florida red scale (Chrysomphalus aonidum)
• Boisduval scale (Diaspis boisduvalii)
• pineapple scale (Diaspis bromeliae)
• flyspeck scale (Gymnaspis aechmeae)
• Lataniae scale (Hemiberlesia lataniae)
Armored ScalesArmored Scales• Eggs found under body of adult
• Females die soon after producing eggs
• Ist instar crawlers disperse to find feeding site, losing
legs after first molt
• Males cannot feed after second molt
ScalesScales
• Usually found on lower surface of older leaves
• Feeding damage results in yellow blotches
UF-MREC
ScalesScales
Infestations may spread rapidly, especially where natural enemies are not present (greenhouse).
Scale ManagementScale Management
Biological control:
Encourage natural enemies; if scales are found, look for presence of natural enemies (lady beetles, emergence holes of parasitic wasps)
Scale ManagementScale Management
Mechanical control:
• Remove individual scales with finger, cotton swab or tool (wash plants after removing adults to wash off eggs)
• Strong water spray
Scale ManagementScale ManagementChemical control:
• Use insecticides labeled for ornamentals or greenhouse use (read label carefully).
• Insecticides don’t kill adult scales, so apply when crawlers are present and repeat application after 7-14 days.
• Insecticidal soaps (no residual
activity) usually require 2-4 applications at 3-7 day intervals.
UF-MREC
MealybugsMealybugs
Many bromeliad growers find mealybugs to be the main insect problem.
MealybugsMealybugs
• Soft-bodied, with waxy coating
• Suck out plant juices with mouthparts
MealybugsMealybugs
Mealybugs often form dense colonies.
Some enclose eggs in a waxy sac.
UF-MREC
UF-MREC
MealybugsMealybugs
• Produce white cottony patches
• Presence of ants may indicate presence of mealybugs (mealybugs produce honeydew)
• Management is as for scale
Root mealybugsRoot mealybugs
• Can become serious because they aren’t easily seen
• Main sign of infestation is decline in plant health
• Remove plant from pot to observe white mealybugs on roots, with waxy material
UF-MREC
Root Mealybug Root Mealybug ManagementManagement
Key to Management is Prevention:
• Inspect roots of newly acquired plants
• Re-pot to avoid root-bound plants
• Use clean pots and media
• Discard or treat (with soil drench) infested plants to prevent spread
• Don’t let water from infested plants drain into clean areas (crawlers can be moved in water)
WeevilsWeevils
• At least 25 species of weevils (mostly Metamasius spp.) are known to attack bromeliads in the neotropics.
• 3 species of Metamasius are now found in Florida.
• First detected in FL in 1989 (Ft. Lauderdale)
• Native to Mexico and Central America
• In south Florida, probably has at least 3-4 continuous generations per year
• Attacks both ornamentals and native Florida bromeliads (resulting in state listing of 2 species as endangered)
Mexican Bromeliad Weevil Mexican Bromeliad Weevil ((Metamasius callizonaMetamasius callizona))
Distribution of Mexican Distribution of Mexican Bromeliad Weevil in FloridaBromeliad Weevil in Florida
• Reported in 17 counties
• By 2001, found in 16 counties
• Northern limits determined by host plant ranges
Mexican Bromeliad Weevil Life Mexican Bromeliad Weevil Life Cycle Cycle
Adult females lay eggs in slits in the leaves close to where they feed.
Larvae mine the meristemmatic tissue, tunneling deep into the base of the plant.
Adults mainly feed on leaves and sometimes on inflorescence.
Pupal (resting) stage is passed in cocoon made from shredded plant material.
J. Salas
J.L. Castner / UF
Symptoms of Weevil Symptoms of Weevil DamageDamage
• Tunneling by the larvae produces holes in the base of the stem, dislodging the
plant from its support structure in the tree.
• Larvae may also tunnel up and damage the inflorescence.
J. Yawn
Symptoms of Weevil Symptoms of Weevil DamageDamage
• Gel produced by plant
• Adult feeding marks on leaves
Symptoms of Weevil Symptoms of Weevil DamageDamage
•
Browning of leaves
Symptoms of Weevil Symptoms of Weevil DamageDamage
• Decomposition of leaves at base (middle of
plant can be pulled out easily)
Bromeliad Genera Bromeliad Genera Known to Be Known to Be
Susceptible in FloridaSusceptible in Florida•Aechmea
•Ananas
•Canistrum
•Catopsis
•Cryptanthus
•Dyckia
•Guzmania
•Hohenbergia
•Neoregelia
•Nidularium
•Orthophytum
•Quesnelia
•Tillandsia
•Vriesea
Florida Bromeliad Florida Bromeliad WeevilWeevil
• Not a threat to Florida’s native bromeliads
• Rarely seen on ornamental bromeliads
• Smaller than Mexican bromeliad weevil
• Attacks seedlings
Other Bromeliad Weevils Other Bromeliad Weevils That Could Potentially That Could Potentially Immigrate to FloridaImmigrate to Florida
Metamasius sellatus
Has been intercepted by USDA/APHIS inspectors on bromeliads entering FL
J. Lotz/DPI
Other Bromeliad Weevils Other Bromeliad Weevils That Could Potentially That Could Potentially Immigrate to FloridaImmigrate to Florida
Metamasius quadrilineatu
s
Has been intercepted by USDA/APHIS inspectors on bromeliads entering FL
Other Bromeliad Weevils Other Bromeliad Weevils That Could Potentially That Could Potentially Immigrate to FloridaImmigrate to Florida
Metamasius flavopictus
Has been found by FL bromeliad growers on imported shipments
J. Lotz/DPI
Other Bromeliad Weevils Other Bromeliad Weevils That Could Potentially That Could Potentially Immigrate to FloridaImmigrate to Florida
Metamasius cincinnatus
J.L. Castner/UF
Other Bromeliad Weevils Other Bromeliad Weevils That Could Potentially That Could Potentially Immigrate to FloridaImmigrate to Florida
Metamasius dimidiatipennis
P. Choate/UF
Other Bromeliad Weevils Other Bromeliad Weevils That Could Potentially That Could Potentially Immigrate to FloridaImmigrate to Florida
Metamasius nudiventris
Other Bromeliad Weevils Other Bromeliad Weevils That Could Potentially That Could Potentially Immigrate to FloridaImmigrate to Florida
Metamasius rugipectus
Management of Management of Bromeliad WeevilsBromeliad Weevils
• Prevention of further spread of Mexican bromeliad weevil: check plants before moving
• Prevention of additional invasives: Import only seeds of bromeliads or apply pesticide dip
Management of Bromeliad Management of Bromeliad Weevils on Ornamental Weevils on Ornamental
BromeliadsBromeliads• Monitor plants frequently for damage and separate infested plants.
• Some growers have successfully used carbaryl (Sevin), but no chemical
trials have been conducted for Mexican bromeliad weevil, and effectiveness in killing eggs is unknown.
Biological Control of Biological Control of Mexican Bromeliad WeevilMexican Bromeliad Weevil
Biological control research in progress:
• Parasitic tachinid fly (Admontia sp.) from Honduras is under study
• Non-target testing needed for release permit
Biological Control of Biological Control of Mexican Bromeliad WeevilMexican Bromeliad Weevil
• Adult fly deposits maggots at tunnel entrance.• Fly maggots seek out weevil larva and feed within.• Maggots come out to pupate.
Biological Control of Biological Control of Mexican Bromeliad WeevilMexican Bromeliad Weevil
• Releases will be made in natural areas in south Florida, where weevil populations are high.
• Parks and other protected lands are priority areas.
• Goal is not to eradicate weevil but to reduce damage.
General Considerations for General Considerations for Management of Insect and Management of Insect and
Related Pests on BromeliadsRelated Pests on Bromeliads• Inspect plants regularly to catch damage early.
• Inspect all incoming plants.
• Unstressed plants can better resist insect damage.
• Phytotoxicity is a problem for bromeliads (test first).
• Never use oil-based insecticides on bromeliads (bromeliads absorb water and minerals through leaves).
• Don’t apply chemical pesticides unless necessary.
• Always read and follow label instructions on pesticides.
For Further For Further Information:Information:
• Florida Council of Bromeliad Societies: http://fcbs.org
• Bromeliad Society International: http://www.bsi.org
• Bromeliad Biota: http://bromeliadbiota.ifas.ufl.edu
• Save Florida’s Native Bromeliads: http://savebromeliads.ifas.ufl.edu
• University of Florida Insect Management Guides: http://edis.ifas.ufl.edu
Author: Barbra Larson, University of Florida
Photos: University of Florida FDACS/DPI Florida Council of Bromeliad Societies O.R. Creel J. Salas J. Yawn R. Cave
Entomology and Nematology Department
University of Florida Copyright 2002