Kava Pest and Disease Image Gallery

Online quick reference for kava growers in Hawaii and the Pacific

By Dr. Scot Nelson, Associate Plant Pathologist, University of Hawaii at Manoa, College of Tropical Agriculture and Human Resources, Department of Plant and Environmental Protection Sciences & Cooperative Extension Service, 875 Komohana St., Hilo, Hawaii 96720 USA (email: snelson@hawaii.edu)

More than 100 digital photos of pests and diseases of Hawaiian ‘awa (kava, Piper methysticum L.) in Hawaii and several reference articles are provided here to help growers diagnose their pest or disease problems. For most images, the resolution and size is set at 150 DPI and (approx. 420 x 375) pixels, respectively, to provide sufficient clarity and size to enable the recognition of the more subtle disease characteristics with confidence. Users of this site may request or submit high-resolution images of kava problems by email. Images are copyright-free.

How to use this site: Pests and kava health problems are listed in brown font below in alphabetical order. Browse and click on an image associated with a particular problem. View, save or print the image. Click on your browser’s “back arrow” to return to this page. If you would like more information, please contact the University of Hawaii Cooperative Extension Service.

A. Free kava pest management articles to download:

1) Integrated pest management for ‘Awa (kava, Piper methysticum) [PDF, 2.5 mb]

2) Kava dieback in Hawaii [PDF, 0.5 mb]

3) Kava root-knot disease [PDF, 1.6 mb]

B. Kava Pest and Disease Image Gallery:

Algae (various): | on leaves (green algae non-parasitic, brown algae is parasitic (Cephaleuros virescens) 1 2 |

Anthracnose (Colletotrichum sp.): | “ring spot” symptom on young leaves in propagation bed 1 | on mature leaves (opportunistic) | pinprick lesions on leaves |

Aphid (Melon aphid, Aphis gossypii): | close-up adult (wingless females) | on honohono grass (Commelina diffusa) | colonies on leaves 1 2 | feeding injury small black pin-spots 1 2 | leaf curling and marginal distortion 1 2 | aphid lion (insect predator of aphids) | ants and aphids |

Barnacle scale (Ceroplastes cirripediformis): | adults on petiole | colony on petiole and leaf |

Basal stem rot (Fusarium sp, other opportunistic fungi): | basal stem rot 1 2 |

Chinese rose beetle (Adoretus sinicus): | damage to leaves |

Chameleon: | chameleon on stem (biological control / insect predator) |

Coconut scale (Aspidiotus destructor): | on leaves | on stem |

Fertilizer burn: | fertilizer burn of tip cuttings | marginal leaf scorching 1 2 | too much osmocote |

Fringe guava whitefly (Aleurotrachelus sp.): | pupae on lower leaf surface 1 2 | yellow spots on upper leaf surface |

Gray garden slug (Deroceras laevae): | adult | damage to leaves |

Green garden looper (Chrysodeixis erisoma): | caterpillar and leaf damage | adult moth and larval case |

Iron deficiency: | on leaves 1 2 |

Katydid: | adult |

Kava dieback (cucumber mosaic virus, CMV): | wilting of young plant | vein clearing and leaf curling | leaf mosaic 1 2 3 4 | leaf rugosity (curling, wrinkling, puckering) 1 2 3 | black leaf veins 1 2 | ring spots on leaves 1 2 | mosaic on honohono grass (Commelina diffusa) | yellow veins and mosaic with leaf puckering | internal stem necrosis and black veins 1 2 | stem splitting | stem lesions and collapse | dieback | leaf spot | vein and leaf puckering and blackening | wilting and dieback of mature plants 1 2 |

Mexican leafroller (Amorbia emigraletta): | caterpillar and leaf damage | pupae |

Mycosphaerella leaf curl (Mycosphaerella sp., fungus): | leaf curl symptom 1 2 |

Node rot (Fusarium sp.): | node rot 1 2 |

Pesticide injury (phytotoxicity): | diazinon | pesticide bleaching |

Potassium deficiency: | K-def on leaf 1 2 |

Pythium root rot and wilt (Pythium splendens): | root rot | wilt 1 2 | rotting of roots and basal stem | root rot and plant decline and stunting |

Root mealybugs: | root mealybugs |

Root-knot nematodes (Meloidogyne spp.): | galled roots 1 2 3 4 5 | internal root necrosis | stem galls | plant yellowing | root rot and galling | nematode head (magnified) | galling and fungal colonization of root

Scale insect (unknown): | on leaf |

Shot hole (Phoma sp.): | leaf symptoms 1 2 3 4 | stem symptoms 1 2 3 | plant dieback and defoliation 1 2 |

Spider mites (carmine spider mite, Tetranchyus cinnarbarinus): | on leaves 2 3 | on stem |

Spiraling whitefly (Aleurodicus dispersus): | flocculent on leaf | foliar damage | spiraling colonies on leaf |

Sunburn: | sunburned leaves 1 2 3 | leaf rugosity and distortion |

Thrips (banana silvering thrips, Hercinothrips bicinctus): | feeding injury - black areas adjacent to leaf veins on lower leaf surface |

Variegated plant (not disease): | variegated plant (chimeric mutation) |

Links: | The Farmer’s Bookshelf | Crop Knowledge Master | Hawaii Pesticide Information Retrieval System | CTAHR homepage |

Pest & Disease Image Galleries: | Koa (Acacia koa) | Kava (Piper methysticum) | Palms | Papaya (Carica papaya) | Noni (Morinda citrifolia) | Coffee (Coffea arabica) |

Photo credits: Scot Nelson, Ph.D.

Site design: Scot Nelson 2005