Catharine Mannion UF/IFAS Tropical Research and Education Center Whiteflies in the Landscape

Transcription

1 Catharine Mannion UF/IFAS Tropical Research and Education Center Whiteflies in the Landscape November 2010

2 Whiteflies Approximately 75 species of whiteflies in Florida. Common pests of many ornamental plants Narrow and wide host range depending on the species Piercing-sucking mouthparts Excrete honeydew Capable of transmitting viruses Adults are small, moth-like, usually with white wings. Typically cause yellowing and leaf drop Photos: H. Glenn, UF/IFAS

3 Whitefly Life Cycle Photo: H. Glenn, UF/IFAS

4 Variability in Whitefly Immature Stages Photo: H. Glenn, UF/IFAS

5 Recent Whitefly Issues in the Landscape in South Florida Gumbo limbo spiraling whitefly Ficus whitefly Cardin s whitefly Whitefly on schefflera

6 Gumbo Limbo Spiraling Whitefly Aleurodicus rugioperculatus First found at USDA office in Miami on Bursera simaruba Spring 2009 Known from Belize, Guatemala and Mexico Eggs are in a spiral pattern Adult is relatively large and docile

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8 Gumbo Limbo Spiraling Whitefly Not much known about biology Closely related to giant whitefly, A. dugesii Adult is about 3 times larger than other whiteflies Adult whiteflies congregate on the undersides of leaves to feed and reproduce Some of the immature stages will secrete long white filaments of wax. It will likely survive year round in south Florida.

9 Giant Whitefly (Aleurodicus dugesii) Pest of hibiscus and several other hosts (ornamentals, citrus, banana, weeds) In California it has been reported on more than 43 hosts Approximately 3 times lager than other types of whitefly Eggs are deposited in a spiral pattern FDACS-DPI, Lotz

10 Adults Gumbo Limbo Spiraling Whitefly

11 Spiraling Eggs Gumbo Limbo Spiraling Whitefly

12 Immature Stages Gumbo Limbo Spiraling Whitefly

13 Parasitoid Identified

14 Avocado Areca palm Brazilian pepper Broadleaf arrowhead Coconut palm Calophyllum species Black olive Buttonwood Cocoplum Copperleaf Plants Hosts Gumbo limbo Live oak Mango Tabebuia species Wax myrtle White bird of paradise Veitchia species Washingtonia palm And, the list continues to grow

15 Population of Gumbo Limbo Spiraling Whitefly

16 Rumors It is killing trees (including coconut palms) It is linked to lethal yellowing It is transmitting a virus Need to use an insecticide preventatively It is only on gumbo limbo Being called coconut whitefly

17 Ficus Whitefly

18 Ficus Whitefly Singhiella simplex (Hemiptera: Aleyrodidae) Only feeds on ficus species Currently in several south and central Florida Counties Photo: H. Glenn, UF/IFAS Will likely spread to areas where ficus is grown Photo: A. Roda, USDA APHIS

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20 Photo: H. Glenn,, UF/IFAS

21 Ficus Hosts Previously Reported (other countries) F. benjamina F. microcarpa F. aurea F. altissima F. bengalensis F. maclellandii Tested (Florida) F. benjamina F. microcarpa F. aurea (native) F. citrifolia (native) F. binnenjikii Alii

22 Ficus Hosts Not Susceptible to the Whitefly F. microcarpa Green Island F. religiosa F. carica (edible fig) F. lyrata F. pumila (= F. repens) F. elastica Burgundy

23 Ficus Whitefly - Damage Causes leaf yellowing Leaf drop (severe) Branch dieback (highly variable) Photo: H. Glenn, and C. Mannion, UF/IFAS

24 Adult Whitefly (2 4 days) Ficus Whitefly Life Cycle Constant temperature (80º F) Eggs (10 days) *2nd 4 th instar puparia (5.8 days) *3rd 1 st instar crawler (4.2 days) 2 nd 3 rd instars nymphs 2 nd instar 3.7 days; 3 rd instar 3. 3 days Photo: H. Glenn, UF/IFAS

25 Parasitoids Collected in Miami on Ficus Infested with Whitefly Amitus bennetti Encarsia protransvena Photos: H. Glenn, UF/IFAS

26 Predators Collected in Miami on Ficus Infested with Whitefly Photos: H. Glenn, UF/IFAS Harmonia axyridis Olla v-nigrum Exochomus childreni Chilocorus nigritis Curinus coeruleus

27 Lacewing Larvae and Eggs

28 Effect of Temperature on Length of Life Cycle (68ºF) (80.6ºF) (86ºF)

29 Effect of Temperature on Egg Hatch (59ºF) (68ºF) (80.6ºF) (86ºF)

30 Ficus Whitefly Trapping Ficus benjamina Isolated area Sticky traps for adult whiteflies Defoliation

31 Ficus Whitefly Mean Trap Catch Trap Direction Up East West Mean Number Adult whiteflies per Trap 3-Mar 24-Mar 14-Apr 5-May 26-May 16-Jun 7-Jul 28-Jul 18-Aug 8-Sep 29-Sep 20-Oct 10-Nov 1-Dec 22-Dec 12-Jan 2-Feb First signs of defoliation (8/28) Freezing Temperatures

32 Ficus Whitefly Mean Trap Catch Mean No. Adult Whiteflies per Trap

33 June approx. 100/trap October approx. 1600/trap August approx. 600/trap December approx. 800/trap Photo: H. Glenn, UF/IFAS

34 Monitoring Ficus Whitefly Monitor ficus plants before you see yellowing and leaf drop It takes several months of having the whitefly before you see the damage Look for the presence of the whitefly Adult whiteflies (not always present) Immature stages and eggs (very difficult to see but important in decision making) Pupal cases (most obvious stage on the leaves, but not the best indicator of control)

35 Another Whitefly Also on Ficus Does not appear to cause the same type of damage Tetraleurodes fici Photo: H. Glenn, UF/IFAS

36 Cardin s Whitefly

37 Cardin s Whitefly Metaleurodicus cardini Been in Florida since 1917 Recent outbreaks seen on Duranta species Similar appearance to the gumbo limbo spiraling whitefly

38 Hosts Reported Allspice Citrus species Barbados cherry Duranta species Eugenia species Fiddlewood Malaleuca Paurotis palm Plumeria Willow bustic

39 Cardin s Whitefly The adult is distinguished readily by the distinct dark spot on each wing.

40 Cardin s Whitefly

41 Whitefly on Schefflera

42 Dialeurodes schefflerae Newly described whitefly species Consistently the most prevalent whitefly on dwarf schefflera grown in Florida Host-specific Also occurs in Hawaii and California

43 Damage

44 Whitefly Stages

45 Whitefly Management

46 Managing Insects with Piercing/Sucking Mouthparts Can be difficult to control Often have short life cycles Often not noticed until populations are high Many have waxy secretions/coverings that provide protection Production of honey dew (for some insects)

47 Management of Whitefly in the Landscape Need long term management which requires other options other than complete reliance on insecticides Natural enemies Alternate plant choices Cultural control Scouting and monitoring

48 Management of Whitefly in the Insecticides Landscape Sometimes important in the early management of a pest Appropriate choices of insecticide, formulation, methods of application and frequency of application Effects on natural enemies

49 Management of Whitefly in the Insecticides Landscape Misuse or overuse can cause problems such as insect resistance, secondary pest problems, environmental contamination, and detrimental effects on non-target organisms Follow label instructions - The site and method of application must be on the label (i.e. landscape, nursery, etc.)

50 Management Options Washing plants off with water Small infestations or small plants Must remove the immature stages and eggs. Horticultural oil or insecticidal soap Strictly contact so thorough coverage is required Several applications are required 7-10 days Phytotoxicity under high temperatures

51 Management Options Apply a systemic (neonicotinoid) insecticide to the soil or trunk Soil application (drench, granular, pellets) Trunk application (basal spray, injection) Expect approximately 1 year control; spring application Note: In the case of ficus whitefly, you can apply a soil systemic as a preventative

52 Neonicotinoids Insecticides Use of these insecticides has grown considerably since the forerunner of the group (imidacloprid) was first introduced in the early 1990 s Acetamiprid Clothianidin Dinotefuran Imidacloprid Thiamethoxam Nitempyram Thiacloprid

53 Neonicotinoid Insecticides Active Ingredient Acetamiprid Clothianadin Trade Names Professional Use TriStar (no soil application) Arena, Aloft* Trade Names Over-the-Counter Dinotefuran Safari Green Light Tree & Shrub Insect Control with Safari Imidacloprid Thiamethoxam Merit, Marathon, Coretect, Discus*, Allectus*, several generic labels Flagship, Meridian Bayer Advanced Lawn Complete Insect Killer; Bayer Advanced Tree & Shrub Insect Control ; Ortho Max * Contains a Neonicotinoid and a pyrethroid

54 What are the Variables Associated with Successful Applications? Type of Plant Growing Environment (container, field, greenhouse, landscape, etc) Target Pest(s) Application Method (foliar, drench broadcast, injection, etc) Ecological Considerations (runoff, leaching, non-targets)

55 UV Stability of Neonicotinoids Slide Credit: Presentation by C. Sclar, Longwood Gardens

56 Slide information courtesy C. Sclar. Longwood Gardens Relative Water Solubility of Neonicotinoids

57 Methods of Application for Neonicotinoids There are numerous options on how to apply the neonicotinoids; Take advantage of the different methods Take advantage of the different formulations Fit the method of application for the site The site and method needs to be on the label

58 Methods of Application Neonicotinoid Insecticides Soil drench need sufficient water to reach the root zone; apply within a couple feet of the trunk Granular applied to the soil surface; follow with irrigation/rain Pellets bury around the trunk Trunk spray spray directly to the lower trunk Trunk injection requires specific equipment to inject into the lower trunk

59 Management Options Foliar Insecticide Application Professional Use (Landscape and Nursery) Whitefly should be present Foliar insecticides may provide quick control, most will not provide long-term control. Some foliar insecticides (i.e. pyrethroids) may disrupt the natural enemies and should be used very selectively. It is not recommended to use the same insecticide on both the foliage and in the soil

60 Insecticide Selection Foliar Application Professional Use (Landscape and Nursery) Abamectin (Avid) Acetamiprid (TriStar) Azadirachtin (Azatin XL) Bifenthrin (Talstar) Buprofezin, (Talus) Clothianidin (Arena) Endosulfan (Endosulfan; Thiodan) Flonicamid (Aria) Horticultural oil Imidacloprid (Merit, Marathon, Discus, Allectus) Pymentrozine (Endeavor) Pyriproxyfen (Distance) Spiromesifen (Judo) Beauveria bassiana (BotaniGard)

61 Foliar Insecticides for Homeowner Use Trade Name(s) Active Ingredient Flower, Fruit & Vegetable Insect Killer (Ortho) Acetamiprid Bug B Gon Max Lawn & Garden Insect Killer (Ortho) Rose & Flower Insect Killer (Bayer Advanced); Lawn & Garden Insect Killer (Schultz) Triazicide Once & Done Insect Killer (Spectracide) Indoor/Outdoor Broad Use Insecticide (Hi-Yield) Yard & Garden Insect Killer (Bonide); Rose & Flower Insect Spray (Spectracide) Bifenthrin Cyfluthrin Lambdacyhalothrin Permethrin Pyrethrin

62 Soil and Foliar Application of Insecticides

63 Soil and Foliar Application of Insecticides

64 Soil and Foliar Application of Insecticides

65 Specific Management Tips Ficus Whitefly Scout immature stages; do not rely on the presence of adults Foliar insecticides only when live whitefly are present Soil or trunk insecticides can be preventative; provide long term control

66 Specific Management Tips Gumbo Limbo Whitefly Scout spiraling eggs on undersides of leaves; easy to see

67 Specific Management Tips Gumbo Limbo Whitefly Foliar insecticides contact may be difficult due to heavy wax production Soil or trunk insecticides use for heavily infested trees; can use for nearby plants or if eggs are present

68 Remember - the below symptoms do not stop or go away immediately even if you are controlling the pest Leaf drop White, waxy flock Sooty mold Do not apply additional insecticide unless you are sure it is necessary

69 Pest Alerts Web Resources University of Florida ( DOACS (

70 Test Your Whitefly Expertise

71 YES YES No No

72 No No No No

73 YES Yes No YES

74 No YES No YES

75 YES No YES No

76 Pest, Predator, Parasite??? Predator Parasite Parasitized Predators

77 Pest, Predator, Parasite??? Pest (pupal skins) Parasite Parasite Parasite

78 Pest, Predator, Parasite??? Parasite Predator Lacewing Predator Beetle Pest Live whitefly

79 Catharine Mannion Research and Extension Specialist Ornamental Entomology University of Florida, IFAS Tropical Research and Education Center SW 280 th Street Homestead, FL