| Crop Knowledge Master | ||
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Nezara viridula (Linnaeus) |
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| Southern Green Stink Bug | ||
| Hosts | Distribution | Damage | Biology | Behavior | Management | Reference | |
Author
Ronald F.L. Mau, Extension Entomologist
Jayma L. Martin Kessing, Educational Specialist
Department of Entomology
Honolulu, Hawaii
Updated by: J.M. Diez April 2007
Food plants comprise a very wide range of fruits and ornamental trees, field crops, vegetables, and weeds. Hosts crops of economic importance include beans, cabbage, chinese cabbage, citrus, crucifers, curcurbits, green beans, head cabbage, macadamia nuts, mango, mustard cabbage, orchids, peppers, potatoes, soybeans, tomatoes, watercress and yardlong beans. Important weed hosts include spiny amaranth, castor bean, popolo berry, rattlepod, spiderweed, and cheese weed. Its omnivorous feeding habits make it an important pest throughout its distribution range.
This pest, is also known in some countries as the green vegetable bug. It occurs throughout the Americas, in various Pacific Islands, Japan, Australia, New Zealand, and Africa. First seen in Hawaii in 1961 on Oahu, it has spread to all major islands.
The bugs feed by piercing plant tissue with needle-like stylets. The actual feeding puncture is not immediately visible. Adults and nearly all nymphal stages (2nd to 5th nymphal stages) feed on a variety of plant tissue. Succulent parts of the plant and the developing flowers or fruit are preferred. Feeding injury becomes visible sometime after actual feeding. Feeding on flower buds results in premature abscission. Feeding injury on leguminous pods results in seed damage and ultimately distorted development of the pods. Nymphal and adult feeding on macadamia nuts often results in spotting or pitting of the kernels and premature abscission. Soft and spongy tissue under otherwise intact epidermis results when the stink bug feeds on vegetable tissue.
The life history and habits of N. viridula have been extensively studied. Life cycle studies conducted at different temperatures, on several hosts, was summarized by Harris and Todd (1980). At 68û - 87.8û eggs hatch in 4 - 5 days and the nymphal development is completed in 25 - 43 days (Drake, 1920; Harris & Todd, 1980). In Hawaii the lifecycle (eggs - adult) is completed in 35 - 45 days.
EGGS
Eggs are deposited on the undersides of leaves in clusters of 40 to 130 (average 70 - 75 eggs). The egg is 1/20 inch high and resembles a nail keg or small drum. They are glued together in 5 - 8 rows. The eggs are yellow-white when laid. In 4 - 5 days the eggs turn pink and become red orange a day later. Eggs hatch in 5 - 8 days. Eggs are found in the field throughout the year in Hawaii.
NYMPHS
Newly emerged nymphs are red and stay on the eggs mass for 48 hours or longer. In this time they darken in color to a reddish brown. The immature bugs must shed their skins 5 times before becoming winged adults. At each molt the bug increases in size, growing form 1/16 inch newly emerged to 1/2 inch at the fifth and last nymphal stage. All nymphs are about as broad as long, dark in color, with red and white or yellow markings on their bodies. The fourth and fifth nymphal stages may be two color phases - light to dark green or black - with characteristic yellow, red and green markings. Immature stink bugs in the 2nd - 4th nymphal stages are often mistaken for lady bird beetles, but close observation will show that nymphs do not have wings, and they also have glands that emit the strong, characteristic odor.
ADULTS
The adult stink bug is shield-shaped, 1/2 to 3/4 inch long, and approximately 5/16 inch wide. They are usually apple or jade green color, but may occasionally be a reddish brown. Adults can live for several months.
After hatching, the first stage nymphs will remain on or near the egg mass. This aggregating behavior will continue through to the fourth nymphal stage. It is believed this behavior is beneficial by shortening the duration on the 2nd stage, decreasing mortality, and increasing the body weight of the emerging adults (Nishida, 1966).
Adults are very active fliers. When disturbed they will fly away or fall to the ground or to lower portions of the plant. The "stink bug" is so named because of the strong odor emitted from scent glands when disturbed. Their green color blends with the foliage making them difficult to find. The southern green stink bug has been reported to move to the upper canopy of crops early in the morning (Hoffman et. al., 1987).
The stink bug is controlled by natural enemies that were deliberately introduced. Several species of egg parasites were introduced.
Cultural Control
Growers who continually experience damage should monitor weed hosts surrounding the crop field. It may be possible to utilize trap-borders of preferred hosts such as Crotalaria (rattlepod) to attract and hold stink bug populations. Stink bugs will usually remain on the plants where parasites can readily find them. It is important that these borders not be allowed to dry before control occurs.
Biological Control -- Parasites
In many places biological control by introduced parasites is so effective that chemical control is seldom necessary (Waterhouse, 1989). In Hawaii, the introduced parasites Trissolcus basalis, Trichopoda pilipes, and Trichopoda pennipes have become established. The first two mentioned above are plentiful and are generally effective in controlling Southern green stink bug populations in Hawaii.
Trichopoda pennipes and Trichopoda pilipes are flies that parasitize adult stink bugs. Both parasites are atracted to male stink bugs but parasitize both sexes (Mitchell and Mau, 1971). They lay oval white eggs on the adult. Maggots that hatch from the eggs penetrate into the stink bugs and feed within. The maggots emerge when mature and the stink bug host dies.
Trissolcus basalis is a wasp that parasitizes eggs. Female wasps deposit their eggs into the stink bug eggs and the larvae complete their development within. The wasp is very efficient and usually parasitizes all of the stink bug eggs in the egg cluster. The average parasitization rate is 95%.
Biological Control -- Predators
Predation by the big headed ant, Pheidole megacephala, has been reported. They prey upon eggs and young gregarious nymphs and carry them back to their nest. Ant predation can be high during periods of low rainfall (Nishida, 1966). Spiders are also know to feed upon the young nymphs.
CHEMICAL CONTROL
Insecticidal applications are usually not required, however sprays may be needed if stink bug populations are high. This pest can be chemically controlled by the use of carbamates and organophosphate compounds. However, because most of these compounds persist on the treated plant for a relatively short period, the crop is vulnerable to reinfestation from nearby areas. Insecticidal control may be improved by using ground equipment to get maximum coverage and by taking advantage of times when the pest is active and not hidden deep within the foliage so insecticides will make contact.
Clausen, C. P. (Ed.) 1978. Southern Green Stink Bug (Nezara viridula (Linnaeus)). pp. 24-26. In USDA Agriculture Handbook #480: Introduced Parasites and Predators of Arthropod Pests and Weeds: A World View. 545 pages.
Davis, C. J. 1964. The Introduction, Propagation, Liberation, and Establishment of Parasites to Control Nezara viridula variety smaragdula (Fabricius) in Hawaii (Heteroptera: Pentatomidae). Proc. Hawaiian Entomol. Soc. 18(3): 369-375.
Davis, C. J. 1967. Progress in the Biological Control of the Southern Green Stink Bug, Nezara viridula variety smaragdula (Fabricus) in Hawaii (Heteroptera: Pentatomidae). Mushi. 39(sup): 9-16.
Harris, V. E. and J. W. Todd. 1980. Duration of Immature Stages of the Southern Green Stink Bug, Nezara viridula (L.), with a Comparative Review of Previous Studies. J. Georgia Entomol. Soc. 15(2): 114-124.
Hill, D. S. 1983. Agricultural Insect Pests of the Tropics and Their Control, 2nd Edition. Cambridge University Press. 746 pages.
Hoffman, M. P., L. T. Wilson, and F.G. Zalom. 1987. Control of the Stink Bugs in Tomatoes. California Agriculture. 41: 4-6.
Lockwood, S. 1957. Green Stink Bugs, Acrosternum hilare and Nezara viridula. In Loose Leaf Manual of Insects Control. California Department of Agriculture.
Lye, B. H., R. N. Story, and V. L. Wright. 1988. Southern Green Stink Bug (Hemiptera: Pentatomidae) Damage to Fresh Market Tomatoes. J. Econ. Entomol. 81(1): 189-194.
Mitchell, W. C. 1965. An Example of Integrated Control of Insects: Status of the Southern Green Stink Bug in Hawaii. Agricultural Science Review. 3(1): 32-35.
Mitchell, W. C. 1966. Southern Green Stinkbug, Leaflet 1. University of Hawaii Cooperative Extension Leaflet. University of Hawaii.
Mitchell, W. C. and R. F. L. Mau. 1971. Response of the Female Southern Green Stink Bug and Its Parasite, Trichopoda pennipes, to Male Stink Bug Pheromones. J. Econ. Entomology. 64(4): 856-859.
Mitchell, W. C., R. M. Warner and E. T. Fukunaga. 1965. Southern Green Stink Bug, Nezara viridula (L.), Injury to Macadamia Nut. Proc. Hawaiian Entomol. Soc. 19(1): 103-109.
Nishida, T. 1966. Behavior and Mortality of the Southern Stink Bug Nezara viridula in Hawaii. Res. Popl. Ecol. 8: 78-88.
Noble, N. S. 1937. An Egg Parasite of the Green Vegetable Bug.N.S. Whales, Misc. Pub. 3094: 337-341.
Waterhouse, D. F. and K. R. Norris. 1987. Nezara viridula (Linnaeus), Hemiptera: Pentatomidae, green vegetable bug (Australia, New Zealand), southern green stink bug (USA). pp. 81-89. In Biological Control: Pacific Prospects. (Ed. D.F. Waterhouse and K.R. Norris). Inkata Press, Melbourne, Autstralia.
OCT/1991.
N-VIRIDU
