Pests and Diseases
The Kirkaldy whitefly (Dialuerodes kirkaldyi)
Kirkaldy whitefly damage to a noni plant growing in Paradise
Park on the Big Island of Hawaii. The older noni leaves are
discolored (dull and brown), crinkled and partially covered
with sooty mold. Severely affected leaves have dying or necrotic
spots or ections, and heavily infested plants may be stunted
and unthrifty in growth. |
Noni leaves heavily infested with the Kirkaldy whitefly may
have brown, necrotic areas between leaf veins. Leaves are cupped
upward, crinkled and show some yellowing near the necrotic areas.
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A close-up of the underside of a noni leaf is heavily infested
with the immature stages of the Kirkaldy whitefly. Their feeding
caused the leaf tissue between veins to become brown and necrotic.
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Thousands of immature Kirkaldy whiteflies on the underside of
an affected noni leaf. |
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Pest: The Kirkaldy
whitefly (Dialuerodes kirkaldyi). Description:
Adults are very small, gnat-like with a light orange body. The
wings are yellowish, and antennae are seven-segmented. The immature
stage is flat, elliptical in shape, yellowish green in color
with a longitudinal brown median area. Three nymphal stages
and one pupal stage occur in the life cycle.
Damage: Leaf discoloration (dulling, browning, yellowing,
necrosis); leaf distortion (curling, crinkling, stunting); slow
and unthrifty plant growth; premature defoliation.
Distribution: The Kirkaldy whitefly was first described
from Hawaii in 1907, but its actual origin is unknown. It is
found on all the main Hawaiian islands. This insect occurs in
Africa (Ivory Coast, Lebanon, Ghana, Egypt), Asia (Burma, China,
Malaysia, Philippines, India, Pakistan, Japan, Syria, Taiwan),
Central America, West Indies (Cuba, Jamaica, Trinidad), South
America (British Guiana), North America (USA: Texas, Florida,
Hawaii), and Australia. Host range: Favored
hosts include noni and Jasmium spp. This pest is also
recorded from Citrus sinensis, Coffee, Beaumontia
grandiflora, Allamanda nerrifolia, and other host
plants in 17 genera and ten docotyledenous families.
Control: |
- Foliar applications of insecticidal soaps and oils.
- Manual detachment and removal of heavily infested leaves.
- Canopy management (thinning).
- Weed control (removes potential alternate hosts).
- Avoidance (avoid introducing infested plants into your
nursery or farm).
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Natural enemies: Encarsia protransvena is a parasitoid of the Kirkaldy whitefly.
Reference:
Ru Ngyuen and Avas B. Hamon (1989). Dialeuroides kirkaldyi (Kotinsky), in Florida (Homptera: Aleyrodidae:Aleyrodinae). Entomology Circular No. 323. Fla. Dept. Agric & Consumer Services. Division of Plant Industry.
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