|Crop Knowledge Master|
Polyphagotarsonemus latus (Banks)
Jayma L. Martin Kessing, Educational Specialist
Ronald F.L. Mau, Extension Entomologist
Department of Entomology
Updated by: J.M. Diez April 2007
This mite attacks many fruit and vegetable crops including bittermelon, Chinese waxgourd, chiso, chrysanthemum, cucumber, edible gourds, eggplant, green beans, guava, hyotan, macadamia, mango, papaya, passion fruit, pepper, pikake, plumeria, poha (ground cherry), pumpkin, tomato, watercress, winged bean, and yardlong beans. Bidens, a common weed, may serve as reservoir host between plant croppings. In temperate and subtropical areas the broad mite is a pest of greenhouse plants (Brown and Jones, 1983).
This mite has a cosmopolitan distribution. It is known to occur in Australia, Asia, Africa, North America, South America and the Pacific Islands. Countries included in this mite's distribution include American and Western Samoa, Bermuda, Brazil, China, Cook Is, Guyana, Fiji, India, Japan, Kiribati, Malaysia, Marianas, New Caledonia, Pakistan, Papua New Guinea, Philippines, Sri Lanka, Taiwan, Tonga, Vanuatu, and Wallis (Waterhouse and Norris, 1987). It is present on all major Hawaiian Islands.
This mite is considered a sub-major pest at low elevations in summer months. Mites feed by piercing plant cells and sucking up the sap that oozes from the wound (Waterhouse and Norris, 1987). Reduction in photosynthesis and instability of water balance are some the damaging effects to plants. Feeding damage also causes terminal leaves and flower buds to become cupped and distorted. As a result of feeding injury, corky brown areas appear between the main veins on the underside on the leaf. Young foliage sometimes becomes rust colored and nearly always is deformed. Blooms abort, and the plant growth is stunted. Damaged leaves often become discolored, thickened and brown (Iacob, 1978).
Damage of flowers and fruits differ among plants. On macadamia, flowers and leaves may appear corky brown or bronze colored. On lemon fruits, feeding results in silvering of the fruit that greatly reduces the market value even though the fruit is otherwise unaffected (Waterhouse and Norris, 1987). On beans, extensive feeding on fruit results in a purplish or dark brown appearance of the pods.
The broad mite does not vector any known plant virus diseases (Waterhouse and Norris, 1987; Higa and Namba, 1970).
The life cycle, from egg to adult, is completed in 4 to 6 days. The number of eggs laid per female and population growth are effected by temperature and relative humidity (Jones and Brown, 1983).
Broad mite eggs are oval in shape and slightly flattened (Lavoipierre, 1940). The exposed translucent surface is covered with five or six rows of white bumps called tubercles. Eggs are about 3/100 inch (0.7 mm) long and can be discerned with a 14X handlens. They are usually laid singly on the undersides of new growth leaves (Hill, 1983). On fruit eggs are laid on the protected surface or in the depressions of the fruit (Waterhouse and Norris, 1987; Brown and Jones, 1983). Eggs usually hatch in 2 to 3 days.
Larvae are very small, pear-shaped (Hill, 1983) and have three pairs of legs. Just after hatching the larvae are translucent, but females become yellowish green or dark green in color and males yellowish brown (Waterhouse and Norris, 1987). The larvae feed for 1 to 3 days before going into the resting pupal stage.
The pupal stage of this mite is a resting period in which there is no feeding. Sexes are similar in appearance, except for the fourth pair of legs. On males the fourth pair of legs are enlarged; on females, the fourth pair of legs are reduced and whip-like (Lavoipierre, 1940). The pupal lasts 2 to 3 days.
The mites are very small and difficult to see without a hand lens. Adult broad mites are elliptically shaped, but slightly wider at the front than the rear (Brown and Jones, 1983). Females are about 3/50 inch (1.5 mm) long and males are slightly shorter and more broad (Lavoipierre, 1940). Live specimens are light, translucent yellowish green. A pale white stripe runs longitudinally down the back of the female. Dead specimens are yellowish brown. They have 4 pairs of whitish legs, but the fourth pair of the female adult is greatly reduced. Females live for about 10 days and lay an average of 2 to 5 eggs per day (20 - 50 eggs per female) (Hill, 1983; Brown and Jones, 1983). Without fertilization, females produce eggs which result in only male progeny (Waterhouse and Norris, 1987).
Larvae and adults prefer to feed on the undersides of leaves usually in the vicinity of the egg.
The adult males have a specialized last pair of legs and are often seen carrying a female pupa over its body. Male pupae are usually not moved, but migrate to new leaf growth carrying a developing female pupa soon after the adult male emerges (Hill, 1983). The males often carry the pupae to newly opened leaves. Copulation occurs immediately after the female has emerged from the pupal skin.
Relative to the males, females are relatively sedentary (Waterhouse and Norris, 1987), but the species is generally considered fast moving (Brown and Jones, 1983).
Throughout the world, specific natural enemies are not known and there have been no attempts at biological control. However, many locally occuring general mite predators give satisfactory control in many areas. Broad mites on passion fruit in Hawaii are satisfactorily controlled by introduced general predators (Waterhouse and Norris, 1987).
This mite is insusceptible to some chemicals, such as dinitrophenol compounds and synthetic pyrethroids (Vaissayre, 1982), used against other members of the pest complex attacking the crop (Waterhouse and Norris, 1987). However, several successful chemical treatments are effective. Many contact pesticides with residual activity do well because of the short egg incubation time (Brown and Jones, 1983). Foliar sprays directed at flush, or new, growth are best. In Hawaii fenbutatin oxide (Vendex) and diazinon provide satisfactory control. Endosulfan provides superior control. Dicofol is effective, but may require a second application a week later in severe attacks (Hill, 1983). Sulfur is effective but requires 2 -3 weeks to achieve control in some crops (eg. macadamia) (Swaine, 1971; Brown and Jones, 1983). Elsewhere, the following treatments are reported to control this pest. Root dipping of chilli seedlings in chlorpyrifos, methamidophos, monocrotophos, phosphamidon, acephate or carbosulfan protects the plant for 28 days after planting (Dhandapani and Jayaraj, 1982). Dimethoate or dinocap are recommended in Tonga (Waterhouse and Norris, 1987). Chemicals should be carefully applied and care should be taken to not interfere with natural enemies that offer biological control of other members of the pest complex .
There are no listings for carbosulfan, endosulfan, methamidophos, phosphamidon, acephate, and Vendex; Dicofol is not labelled as of April 2007.
Brown, R.D. and V.P. Jones. 1983. The Broad Mite on Lemons in Southern California. California Agriculture. 37(7/8) 21-22.
Denmark, H.A. 1980. Broad mite, Polyphagotarsonemus latus (Banks) (Acarina: Tarsonemidae) on Pittosporum. Fla. Dept. Agric. and Consumer Services Division of Plant Industry. Entomology Circular No. 213.
Dhandapani, N. and S. Jayaraj. 1982. Effect of Chilli Seedling Root Dip in Insecticides for the Control of Sucking Pests. Pestology. 6(3): 5-10.
Ewing, H.E. 1939. A Revision of the Mites of the Subfamily Tarsoneminae of North America, the West Indies, and the Hawaiian Islands. U.S. Dept. Agri. Tech. Bull. No. 653. 64 pages.
Higa, S.Y. and R. Namba. 1971. Vectors of the Papaya Mosaic Virus in Hawaii. Proc. Hawaiian Entomol. Soc. 21(1): 93-96.
Hill, D. S. 1983. Polyphagotarsonemus latus (Banks). pp. 504. In: Agricultural Insect Pests of the Tropics and Their Control. Cambridge University Press. 746 pages.
Iacob, N. 1978. New Mite Pests on Greenhouse Crops and on Grapevine (abstract only). Rev. Appl. Entomol. Ser. A. 67(12): 595-596.
Jones, V.P. and R.D. brown. 1983. Reproductive Responses of the Broad Mite, Polyphagotarsonemus latus (Acari: Tarsonemidae), to Constant Temperature-Humidity Regimes. Ann. Ent. Soc. Am. 76(3): 466-469.
Lavoipierre, M.M.J. 1940. Hemitarsonemus latus (Banks) (Acarina), a Mite of Economic Importance New to South Africa. J. Entomol. Soc. Southern Africa. 3: 116-123.
Waterhouse, D.F. and K.R. Norris. 1987. Chapter 31: Polyphagotarsonemus latus (Banks). In: Biological Control Pacific Prospects. Inkata Press: Melbourne. 454 pages.
Vaissayre, M. 1982. Observations relating to the economic impact of acariosis caused by Polyphagotarsonemus latus (Banks) in cotton crops (abstract only). Rev. App. Entomol. Ser. A. 71(6): 509.