Invasive Species Compendium

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Abstract

The more important Insect Pests of Sugar Cane in northern Venezuela.

Abstract

The author describes the distribution of sugar-cane cultivation in Venezuela [cf. R.A.E., A 37 273] and gives short accounts of the occurrence and economic importance of the insects that attack the crop in any of the localities concerned, with records of their natural enemies.
Most of the information on the Pyralids, Diatraea saccharalis (F.), D. imper-sonatella (Wlk.), D. canella Hmps., D. busckella Dyar & Heinr. and D. rosa Heinr., and their parasites has already been noticed [cf. 37 273; 39 93]. The latter include the egg parasite, Trichogramma minutum Ril. (evanescens, auct.), which is widespread, and a Tachinid considered by F. van Emden to be close to z enillia ochracea Wulp, which is local and rare. Castnia licoides Boisd. is common on sugar-cane only at two places in Carabobo State, but may be of considerable potential importance; larvae of Castnia sp., possibly C. licoides, have been found in Tachira and at Upata, south of the Rio Orinoco. No natural enemies have been observed, but Zenillia palpalis Aldr., which occurs as a parasite of Diatraea, was originally reared from C. licoides in British Guiana [cf. 39 93].
Adults of several species of Lachnosterna are sometimes abundant near the sugar estates, but the larvae are not important, and the only injurious Lamellicorn present is the Dynastid, Podischnus agenor (Ol.), which is common from Sucre to Tachira and has sometimes caused heavy damage in Carabobo; it appears recently to have become established in the important cane zones of the Turbio and Tocuyo valleys (Lara). The larvae normally occur in soils over-rich in decomposing vegetable matter and rarely feed on living plant tissue. The adults appear in large numbers at the beginning of the rainy season (April-May) and burrow into the cane stalks. The only parasite observed is Campsomeris servillei (Guer.), which occurs from Monagas State to Merida. P. horni, Sternb. was collected on one sugar estate in Tachira, but its status is not known. The weevil, Metamasius hemipterus (L.), is found in nearly every sugar-cane area; its attacks usually follow those of Diatraea, but it occasionally causes serious damage.
Saccharicoccus (Trionymus) sacchari (Ckll.) is one of the most widely distributed pests and occasionally causes severe injury, especially during the dry season, on small isolated farms on which the fields have been neglected. Outbreaks are localized and accompanied by large numbers of ants. On the larger estates and plantations, the Coccid appears to be adequately controlled by native predators, of which Hyperaspis trilineata Muls, appears to be the most important. Sipha flava (Forbes) is also widely distributed but only occasionally injurious. The worst damage occurs in fields of young plant canes, the development of which may sometimes be seriously impeded, and appears to be associated with poor agricultural conditions and with the occurrence of root diseases. The Aphid is commonly attacked by larvae of Coccinellids, particularly Cycloneda sanguinea (L.) and Ceratomegilla (Coleome-gilla) maculata (Deg.), and Chrysopids. Aphis maidis Fitch is apparently rare, but mosaic disease, of which it is a well-known vector, is widespread.
The Jassid, Rhopalogonia scita (Wlk.), which appears to be unknown as a pest elsewhere, has been found on sugar-cane in numerous localities, but severe outbreaks seem to occur only at heights of about 4, 000 ft. or more. All stages are present on the leaves of sugar-cane, maize and certain wild grasses. Heavy outbreaks of the Delphacid, S aecharosydne saccharivora (Westw.), occur annually in Carabobo and a few other places, but do not cause serious damage as they are rapidly controlled by predators, particularly Coccinellid and Chrysopid larvae, and the plants soon recover.
Cercopids have recently become major pests of sugar-cane in Venezuela, the most important and widely distributed of them being Aeneolamia varia sontica Fennah. Others that may sometimes be of local importance include seven of the other subspecies of A. varia recorded by Fennah [40 388], a list of which is given, A. flavilatera subsp. [caripensis Fennah] and Delassor tristis monagasi Fennah.