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University of Florida Extension

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Presentation on theme: "University of Florida Extension"— Presentation transcript:

1 University of Florida Extension
Key Plants and Key Pests in North Florida Landscapes Podocarpus, Gardenia, Camellia, and Pyracantha Rebecca McNair University of Florida Extension

2 IPM Integrated Pest Management
Natural processes of control are emphasized Host plant resistance Pest exclusion Prevention and through cultural practices Physical Control Biological control through natural enemies Chemical control as a last resort Tolerance Monitoring

3 Podocarpus Nageia nagi

4 Podocarpus- Key Pests Diseases Mushroom root rot Other Nematodes
Magnesium deficiency

5 Mushroom Root Rot Slow decline, thinning of canopy Gray-green color
White mycelia under bark at soil line Armillaria tabescens

6 Armillaria tabescens fruiting body appears in fall.
Root Rot Management Remove diseased plants and roots Fumigate soil before replanting Armillaria tabescens fruiting body appears in fall.

7 Root nodules Beneficial nitrogen-fixing blue green algae
Often mistaken for root knot nematodes Active nodules have a pink milky fluid in their centers Hemoglobin within the nodule fixes atmospheric nitrogen. When exposed to oxygen, the fluid inside changes from blue to pink!

8 Roots infected with Meloidogyne are swollen.
Root Knot Nematodes Endoparasitic nematode Feeds on root tissues Dieback, decline, chlorosis Identify under microscope Roots infected with Meloidogyne are swollen.

9 Nematode Management Fumigate Solarize soil
egg mass Fumigate Solarize soil Buy plants grafted with resistant varieties Provide adequate water and fertilizer Remove and replace plants and soil Meloidogyne sp.

10 Magnesium Deficiency Management Increase pH with dolomite
Yellow inverted “V” Occurs on mature leaves Low soil pH Lack of soil Mg Management Increase pH with dolomite Apply Epsom salts or Mg fertilizers

11 Gardenia augusta Acid loving plant Fragrant flowers

12 Gardenia- Key Pests Diseases Stem Canker Other Nematodes
Manganese deficiency Environmental stress

13 Stem Canker Sudden wilting Chlorosis Leaf spots
Yellow halo around lesions Stem cankers Galls, usually at the soil line Girdling may occur

14 Stem Canker Management Fungus pathogen enters injured tissue
Spores spread by splashing water Management Minimize plant injury Avoid overhead irrigation Phomopsis gardeniae Notice the yellow halo around the leaf spots on this gardenia.

15 Nematodes Roundworms Root Knot nematodes live inside plant roots
All live in liquids, i.e. water in soil Feed on plant sap Damage roots Inhibit growth

16 Decline due to root knot nematodes compared to a healthy gardenia.
Decline and thinning of canopy Roots brown, stunted and galled Decline due to root knot nematodes compared to a healthy gardenia.

17 Nematode Management Fumigate Solarize soil
Buy plants grafted with resistant varieties Provide adequate water and fertilizer Remove and replace plants and soil Meloidogyne sp

18 Manganese Deficiency Management Interveinal chlorosis on new growth
Reduced leaf size Necrotic distortion of new growth Common in alkaline soils high in phosphorous Management Use a complete fertilizer with micronutrients

19 Environmental Stress Management Excessive water or fertilizer
Cold or temperature fluctuation Nutrient Deficiency Drought High pH Mechanical damage Management Correct cultural problems Provide cold protection Prune and re-grow Chlorosis Bud drop

20 Camellia japonica Acid loving Prefers partial shade
Fragrant flowers from late winter to early spring

21 Camellia- Key Pests Diseases Crown Gall Petal blight Leaf spot Other
Twig dieback Other Environmental stress

22 Gall Galls can appear on any plant part and may be due to bacteria, fungi, nematodes, or insects. Agrobacterium tumefaciens is a common soil bacterium that causes crown gall disease by transferring some of its DNA to the plant host This has enabled scientists to genetically manipulate plants, a technique called transformation.

23 Petal Blight Irregular, brown spots Dark veins Blighted flowers drop
Prefer warm, moist conditions Ascospores are spread by water Fungus overwinters as sclerotia, a hard black structure that remains viable for 5 years Cibornia camelliae (formerly Sclerotinia) Sclerotia

24 Cibornia camelliae fruiting body.
Petal Blight Control Suppress sclerotia development Remove all infected flowers, leaves, and litter Promptly burn or bury diseased materials (at least 1 ft deep) Limit overhead irrigation Cibornia camelliae fruiting body.

25 Fungal Leaf Spot Management Circular or irregular lesions
Margins raised Brown - gray Fungus favors high humidity and partial shade Management Limit overhead irrigation Avoid crowding Copper fungicides Cerscospora caloloma

26 Algal Leaf Spot Wide host range
Smooth leathery leaves are more prone to infection One of the few green algae parasitic on higher plants Management Limit overhead irrigation Cephaleuros virescens

27 Twig Dieback Fungus Summer-winter: cankers Spring:
Young shoots wilt and die Brown leaves remain on the dead shoots Glomerella cingulara Twig dieback and a healthy camellia.

28 Twig Dieback Management Prune infected areas, including cankers
Leaf scars are most common point of entry Often confused with root rots Plants can be infected by both Root rot increases the severity of twig dieback Management Prune infected areas, including cankers Fungicides

29 Environmental Stress High heat and light Temperature fluctuation
Drought Mechanical damage Management Maintain adequate water Bud Drop

30 Pyracantha coccinea Firethorn Prefers full sun
Will grow in partial to fairly heavy shade Fast growing

31 Pyracantha- Key Pests Diseases Fireblight

32 Fireblight Bacterium New shoots wilt suddenly and die
Dead leaves remain on the shoots Spread by bees and splashing water Erwinia amylovora

33 Fireblight Management
Bacteria enter through flowers and infection spreads into the stem Management Limit overhead irrigation Remove infected branches Use resistant varieties

34 Acknowledgements Authors: Rebecca McNair Reviewers: Dr. Russ Mizell, Dr. Norman Leppla, Dr. Doug Caldwell, Celeste White, and Christine Kelly- Begazo Funding: Florida Yards and Neighborhoods Photos: Thanks to the Florida Dept. of Agriculture and Consumer Services, Division of Plant Industry, and University of Florida Extension faculty for providing photographs, including: Dr. James Castner Dr. Catherine Mannion Dr. Lance Osborne Dr. Avas Hamon Dr. Norman Leppla Dr. George Agrios Bill Graves Dr. Doug Caldwell Holly Glenn Dr. Tim Schubert Dr. Eileen Buss

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