Agricultural Entomology

Insects damage crop plants and reduce the value of agricultural produce by eating the vegetative parts and fruits, by acting as vectors of diseases (Carter 1973), or by contamination with their presence. Damage may be reflected in a variety of ways: wilted leaves, dead stems, discolored or spoiled fruit, gall formation (Fernandes 1987), and often the death of the plant. Loss of food, textile fiber, and ornamental plant produce in Latin America cannot be calculated with accuracy but surely runs into equivalents of billions of dollars annually.

No country or any plant of the great spectrum of Neotropical cultigens is immune from the depredations of injurious insects and mites; the problems are universal, as evident from several general publications (Caswell 1962; Fröhlich and Rodewald 1970; Gallo 1988; Hill 1983; Kranz et al. 1979; Ebeling 1959; Flechtmann 1983). A variety of reviews or catalogs of agricultural pests describe local situations: Argentina (Rizzo 1977, Molinari 1948), Brazil (Bon-dar 1913), Central America (King and Saunders 1984, Saunders et al. 1983), Co lombia (Anonymous 1968), Cuba (Bruner et al. 1975), Dominican Republic (Sontoro 1960), Guatemala and El Salvador (Bates 1932), Honduras (Passoa 1983), the Lesser Antilles (Fennah 1947), Mexico (Mac-Gregor and Gutiérrez 1983, Morón and Terrón 1988), Peru (Wille 1952), Puerto Rico (Chiesa Molinari 1942), Surinam (van Dinther 1960), and Uruguay (Ruffinelli and Carbonell 1954).

Most injurious species are adapted to a particular host, but a few attack almost any plant, the best examples being migratory locusts (Schistocerca) and leaf cutter ants (Acromyrmex, Atta; Cherrett and Peregrine 1976). The following are some of the more important pests of widely grown crop species encountered by Latin American agronomists.

The most serious enemies of the cacao tree (Leston 1970, Entwhistle 1972) are scale insects (Pseudococcus, Planococcus, Dys-micoccus) that act as vectors of viruses and fungal diseases, causing dieback and significant fruit reduction on affected plants. The cacao thrips (Selemnothrips rubrocinctus) and aphids (e.g., Toxoptera aurantii) cause similar damage.

Coffee trees serve as hosts to over two hundred insect species (Le Pelley 1968, 1973). The trunks and stems are susceptible to the larvae of a variety of boring beetles in Latin America, especially the coffee berry borer (Hypothenemus hampei, Scolytidae), which causes the dropping and decaying of berries, and "black borers" (Apate, Bostrichidae) that hollow the stems. The coffee leaf miner (Leucoptera coffeella, Lyonetiidae) damages leaves to such a degree that they fall off the plant. Leaf curl, burning, and stunting are commonly caused by various mealybugs (Pseudococcus) and scale insects.

The attacks of several kinds of lepidop-terous stem borers can cause the virtual loss of entire crops of rice (Cheaney and Jennings 1975, Grist and Lever 1969). In Latin America, the chief offenders in this category are Diatraea spp. and other Pyralidae (Kapur 1964).

Corn (maize) is native to the New World, but this gives it no immunity to many introduced pests such as earworms (Heli-coverpa spp., Noctuidae) that destroy the kernals and stem borers, mainly pyralid moths of the genus Diatraea, that may cause the entire plant to droop and die. Other pests include leaf destroyers, many leaf beetles (Chrysomelidae), and a host of other noctuid leaf worms and cutworms.

Although manioc (mandioca, cassava, yuca, tapioca) suffers from relatively few arthropod pests, they can cause extensive damage to this important food crop (Bellotti and van Schoonhoven 1978, Samways and Ciociola 1980). The cassava shoot-fly, Neosilva perezi (Lonchaeidae; sometimes erroneously cited as Silba or Lonchaea chalybea), is widespread and does major damage. Young larvae mine in growing shoots and may cause the entire shrub to die. The manioc gall midge (Latrophobia [= Autodiplosis, Eudiplosis] brasiliensis, Ceci-diomyiidae) is well known because it causes an obvious deformation, red galls, on the leaves of plants it attacks. These galls reduce photosynthesis but rarely bring about loss of vitality of the whole plant. In parts of Brazil, the galls are known as mamica de rama or veruga da mandioca. Spider mites should also be counted among the more serious pests, especially Tetranychus and Monony-chellus spp. The larvae of the ashy sphinx, Erinnyis ello (Winder 1976), and pyralid moth Chilozela (Becker 1986) feed directly on manioc leaves.

The vegetative parts of the banana plant are attacked by the mealybug Pseudococcus comstocki (Ostmark 1974). Adult banana fruit-scarring beetles (Colaspis hypochlora) eat the young, unfurled leaves and stems plus the fruit, causing scars that make the latter unsalable and allowing the entry of decay microbes. The banana thrips (Herd-nothrips bicinctus) feeds on the fruit, discoloring it and reducing its market value, but it does not cause systemic effects on the plant. Plants are killed in many areas from the borings of banana weevil (Cosmopolites sordidus) larvae in the rhizome and pseudo-stem at ground level.

The pink bollworm (Pectinophora gossy-piella) is the most important pest of cotton and occurs in nearly all growing areas. Heavy feeding on the bolls by the larvae leads to fiber loss and seed destruction. The cotton bollworm (Helicoverpa zea) and the famous cotton boll weevil (Anthonomus grandis) (Burke et al. 1986) both do similar damage. Red spider mites, especially (Tetranychus cinnabarinus), cause the leaves of cotton plants to wither and drop off. The cotton aphid (Aphis gossypii) also often infests the foliage.

Pineapple is damaged directly by the root-feeding pineapple mealybug (Dysmicoc-cus brevipes, Pseudococcidae) but also suffers from an associated fungus wilt disease (Phytophthora) that causes leaf degeneration and small fruit.

Citrus is impossible to grow profitably in many areas because of the attacks of numerous insects (Ebeling 1959). Most serious are the citrus spider mites, including Metatetranychus citri, and the six-spotted mite (Eotetranychus sexmaculatus). Considerable damage also results from overwhelming populations of citrus white flies (Tri-aleurodes, Dialeurodes, Aleyrodidae) and scale insects (California red scale, Aonidiella aurantii; West Indian red scale, Sclenaspidus articulatus; and citrus mussel scale or purple scale, Lepidosaphes beckii). The maggots of the fruit flies (Rhagoletis, Anastrepha), especially the Mediterranean fruit fly (Ceratitis capitata, Tephritidae), may account for almost total fruit losses in heavily infested areas. Mealybugs (e.g., Planococcus citri) are also a major problem.

Sugarcane also comes under attack from a large number of insects and mites (Long and Hensley 1972, Guagliumi 1972-73, Williams et al. 1969). Froghoppers, particularly the sugarcane froghopper (Aeneolamia varia saccharina, Cercopidae), are this crop's most serious pest in many countries. Sap feeding by the nymphs on the roots results in withering of the leaves and stunted stalks. The cane leafhopper (Sac-charosydne saccharivora) is a troublesome species in Jamaica and elsewhere. Many subterranean, root-feeding scale insects, mealybugs, cicadas, and scarab beetle larvae ("white grubs") are also prevalent in various areas. Several stalk-boring larvae of the pyralid moth genus Diatraea (especially the sugarcane borer, D. saccharalis) are recognized as primary pests as well. Aphids (Aphis sacchari, Sipha flava) serve as vectors of virus and fungal diseases and injure the plants directly by sap removal.

Other crops and their major pests in Latin America are avocado (fruit flies, Tephritidae); alfalfa (spotted alfalfa aphid, Therioaphis maculata)\ beans (bean aphid, Aphisfabae)\ coconut palm (Lever 1969) (coconut scale, Aspidiotus destructor; coconut mite, Eriophyes guerreronis; planthopper, Myndus crudus, vector of lethal yellowing disease) (Howard et al. 1983); guayaba (fruit flies) (Espinoza 1972); maguey (fruit flies, Euxesta); mango (fruit flies); potatoes (potato tuberworm, Phthorimaea operculel-la); papaya (fruit flies); sorghum (sugarcane borer, Diatraea saccharalis) (Young and Teetes 1977); tobacco (tobacco and tomato hornworms, Manduca sexta and M. quinque-maculata); and wheat (wheat thrips, Frank-liniella tritici).

References

Anonymous. 1968. Catálogo de insectos en cultivos de importancia económica en Colombia. Assoc. Latinoamer. Entomol. Publ. 1: 1-156. Bates, M. 1932. Insectos nocivos: Estudio de las principales plagas guatemaltecas con algunos datos de Honduras y El Salvador. Serv. Tec. Coop. Agrie., Unit. Fruit Co., Guatemala City. Becker, V. O. 1986. Correct name for the species of Chilozela (Lepidoptera: Pyralidae) whose caterpillars damage cassava in South America. Bull. Entomol. Res. 76: 195-198. Bellotti, k. A., and A. van Schoonhoven.

1978. Mite and insect pests of cassava. Ann. Rev. Entomol. 23: 39-67.

Bondar, G. 1913. Os insectos daninhos na agricultura. Sec. Agrie. Indus. Comm., Säo Paulo.

Bruner, S. C., L. C. Scaramuzza, and A. R. Otf.ro. 1975. Catálogo de los insectos que atacan a las plantas económicas de Cuba. 2d ed. Acad. Cien. Cuba, Insto. Zool., La Habana.

Burke, H. R., W. E. Clark, J. R. Cate, and P. A. Fryxell. 1986. Origin and dispersal of the boll weevil. Entomol. Soc. Amer. Bull. 32: 228-238.

Carter, W. 1973. Insects in relation to plant disease. 2d ed. Wiley, New York.

Caswell, G. H. 1962. Agricultural entomology in the tropics. Arnold, London.

Cheaney, R. L., and P. R. Jennings. 1975. Problemas en cultivos de arroz en América Latina. Centr. Int. Agrie. Trop. (Ser. GS-15), Cali.

Cherrett, J. M., and D. J. Peregrine. 1976. A review of the status of leaf-cutting ants and their control. Ann. Appl. Biol. 84Í 128-133.

Chiesa Molinari, O. 1942. Entomología agrícola, identificación y control de insectos y otros animales dañinos o útiles a las plantas. Talleres Gráficos Accurziol, San Juan.

Chiesa Molinari, O. 1948. Las plagas de la huerta y el jardín y modo de combatirlas. Ed. Bell (Bibl. Pampa Argentina, Rev. Min. Agrie. Gan. Int. Gen. Serv. Pais), Buenos Aires.

Ebeling, W. 1959. Subtropical fruit pests. Univ. Calif. Press, Berkeley.

Entwhistle, P. F. 1972. Pests of cocoa. Longmans, London.

Espinoza, W. O. 1972. Control fitosanitario en plantaciones de guayaba. Univ. Indus. Santander, Bucaramanga, Colombia.

Fennah, R. G. 1947. The insect pests of food crops in the Lesser Antilles. Dept. Agrie. Antigua, British West Indies. [Not seen.J

Fernandes, G. W. 1987. Gall forming insects: Their economic importance and control. Rev. Brasil. Entomol. 31: 379-398.

Flechtmann, C. H. W. 1983. Acaros de im-portäncia agrícola. Liv. Nobel, Säo Paulo.

Fröhlich, G., and W. Rodewald. 1970. Pests and diseases of tropical crops and their control. Pergamon, Oxford.

Gallo, D. 1988. Manual de entomología agrícola. 2d ed. Ed. Agron. Ceres Ltda., Säo Paulo. [Not seen.]

Grist, D. H., and R. J. A. W. Lever. 1969. Pests of rice. Longmans, London.

Guagliumi, P. 1972—73. Pragas de cana de adúcar no nordeste do Brasil. MIC, Insto., Adúcar e do álcool, Dr. Ad., Ser. Doc. Colegäo Canavieira 10, Rio de Janeiro.

Hill, D. S. 1983. Agricultural insect pests of the tropics and their control. 2d ed. Cambridge Univ. Press, Cambridge.

Howard, F. W., R. C. Norris, and D. L. Thomas. 1983. Evidence of transmission of palm lethal yellowing agent by a planthopper, Myndus crudus (Homoptera: Cixiidae). Trop. Agrie. 60: 168-171.

Kapur, A. P. 1964. Taxonomy of the rice stem borers. In Int. Rice Res. Inst., The major insect pests of the rice plant. Johns Hopkins Univ. Press, Baltimore. Pp. 3-43.

King, A. B. S., and J. L. Saunders. 1984. The invertebrate pests of annual food crops in Central America. Trop. Devel. Res. Inst., Overseas Devel. Adm., London.

Kranz, J., H. Schmütterer, and W. Koch. 1979. Diseases, pests, and weeds in tropical crops. Wiley, New York.

Le Pelley, R. H. 1968. Pests of coffee. Longmans, London.

Le Pelley, R. H. 1973. Coffee insects. Ann. Rev. Entomol. 18: 121-142.

Leston, D. 1970. Entomology of the cocoa farm. Ann. Rev. Entomol. 15: 273-294.

Lever, R. J. A. W. 1969. Pests of the coconut palm. United Nations Food Agrie. Org. Agrie. Ser. 77: 1-190.

Long, W. H., and S. D. Hensley. 1972. Insect pests of sugarcane. Ann. Rev. Entomol. 17: 149-176.

MacGrf.gor, R., and O. Gutiérrez. 1983. Guía de insectos nocivos para la agricultura en México. Ed. Alhambra Mexicana, Mexico City.

Morón, M. A., and R. A. Terrón. 1988. Entomología practica. Insto. Ecol., México.

Ostmark, H. E. 1974. Economic insect pests of bananas. Ann. Rev. Entomol. 19: 161-176.

Passoa, S. 1983. Lista de los insectos asociados con los granos básicos y otros cultivos selectos en Honduras. Ceiba 25: 1-97.

Rizzo, H. F. E. 1977. Catálogo de insectos perjudiciales en cultivos de la Argentina. 4th ed. Hemisferio Sur, Buenos Aires.

Ruffinelli, A., and C. S. Carbonell M. 1954. Segunda lista de insectos y otros artrópodos de importancia económica en el Uruguay. Assoc. Ing. Agron. Montevideo Rev. 94: 33-82.

Samways, M. J., and A. I. CiocioLA. 1980. O complexo de artrópodos da mandioca (Manihot esculenta) Crantz em Lavras, Minas Gerais, Brasil. Soc. Entomol. Brasil An. 9: 3-10.

Saunders, J. L., A. B. S. King, and C. L. Vargas. 1983. Plagas de cultivos en América Central. Centro. Agron. Trop. Inves. Ens., Turrialba, Costa Rica.

Sontoro, R. 1960. Notas de entomología agrícola dominicana. Sec. Estad. Agrie. Comer., Rep. Dominicana, Santo Domingo. [Not seen.]

van Dinther, J. B. M. 1960. Insect pests of cultivated plants in Surinam. Landbouwproef-station Suriname Bull. 76: 1 — 159.

Wille, J. E. 1952. Entomología agrícola del Perú. 2d ed. Min. Agrie., Lima.

Williams, J. R., J. R. Metcalf, R. W. Montgomery, and R. Mathes, eds. 1969. Pests of sugarcane. Elsevier, Amsterdam.

Winder, J. A. 1976. Ecology and control of Erinnyis ello and E. alope, important insects in the New World. Pest Art. News Sum. 22: 449-466.

Young, W. R., and G. L. Teetes. 1977. Sorghum entomology. Ann. Rev. Entomol. 22: 193-218.

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