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A serious infestation of Mediterranean fruit fly in Florida in 1997 and 1998 led to the widespread aerial and foliar application of malathion-bait sprays. Public concerns over property damage, environmental impact and public health led to the immediate need and acceptability of alternative pesticide/bait combinations. Preliminary work with spinosad, a derivative of a soil microorganism developed by Dow AgroSciences, in combination with a new bait (SolBait) showed promise. To ensure that this product would be effective in Florida for fruit fly control, three field tests were conducted using aerial and/or foliar applications. Results indicated that sprays with spinosad-SolBait provided comparable and significant control levels for sterile Mediterranean and Caribbean fruit flies in comparison to standard malathion with NU-LURE® or SolBait treatments by aerial or foliar application. In one test, honey bees and hives were exposed to sprays in the treatment area and no significant treatment differences were observed in hive condition or brood. Insufficient data on effects of treatments on naturally occurring and introduced beneficial insects were collected for statistical analysis but it appears no harmful effects were observed.

Scotch broom, Cytisus scoparius (L.), a weed in the Pacific Northwest, is rapidly invading open areas and ecologically sensitive dunes along the coast. Scotch broom populations also exist in the eastern United States, but are apparently stable and not expanding. The eastern Scotch broom populations may be kept in check by the broom weevil, Bruchidius villosus (F.), a bruchid found in eastern populations of broom but absent from those in the Northwest (Bottimer 1968). We studied the natural history and biology of the broom weevil in North Carolina. Our purpose was to relate the bruchidis life history to the phenology of the host plant and to quantify oviposition and seed destruction by the bruchids. Adult weevils were active around the plant from the first flowering in early spring until dehiscence of the seedpods in summer. The sex ratio of the beetles was nearly 1:1 throughout the adult activity season. The number of weevil eggs laid on the pods was correlated to the length of the pod and to the number of seeds in the pod. The larvae develop in and destroy the seeds of the broom plant. Seed destruction at two sites in North Carolina was more than 80%; a field experiment showed that seed destruction was dependent on the density of beetles in cages on the plants. Because of its impact on seed production, the broom weevil may be a viable candidate for biological control of broom in the Northwest.

We tested the host specificity of two South American Pseudacteon phorid flies, P. obtusus Borgmeier and P. borgmeieri Schmitz, on North American colonies of the red imported fire ant, Solenopsis invicta Buren, and the tropical fire ant, S. geminata (F.). Sequential host specificity tests conducted in the laboratory indicated that P. obtusus was highly specific to S. invicta. In individual trials, 20 females attacked S. invicta but none attacked S. geminata. Pseudacteon borgmeieri females, in contrast, attacked both Solenopsis species. Six of the eighteen known South American Pseudacteon species have now been tested for host specificity, and 4 of the 6 reveal a high degree of specificity to S. invicta, thus representing good biocontrol candidates.

Cirrospilus floridensis, reared from the citrus leafminer, Phyllocnistis citrella Staintain, is described and illustrated. Zagrammosoma zebralineatum De Santis and Pnigalio flavipes (Ashmead) are synonymized with Zagrammosoma multilineatum (Ashmead) and Pnigalio minio (Walker), respectively.

Natural infestations of Tapinoma melanocephalum, (Fab.) found in central Florida greenhouses were observed attacking Tetranychus urticae Koch in test evaluations of two chemicals. Subsequent laboratory tests using isolated leaf discs, greenhouse data, and whole plants demonstrated that T. melanocephalum is a significant predator of T. urticae.

Rearing techniques for Ageniaspis citricola and Cirrospilus quadristriatus and their host, the citrus leafminer, Phyllocnistis citrella, are discussed as related to a classical biological control program. Methods for rearing the three trophic levels (citrus plants, leafminers, and parasitoids) are described in detail. An average of 1,155 adult citrus leafminers were produced in a cage filled with 60-72 young citrus trees. Between April and October 1994, a total of 15,230 A. citricola were produced, with an average of 750 adults per cage. Between late July and October 1994, a total of 1,328 C. quadristriatus were produced, with an average of 144 adults per cage. The two parasitoids were released into leafminer-infested citrus groves throughout Florida in a classical biological control project.

Bagous affinis Hustache (Coleoptera: Curculionidae) has potential as a biological control agent for subterranean turions (also called tubers) of hydrilla (Hydrilla verticillata (L.f.) Royle; Hydrocharitaceae). The ability of B. affinis to overwinter and establish was investigated at 2 sites in northern California; a pond in Calaveras County and the Chowchilla River in Madera County. In cage studies conducted at the pond, B. affinis survived the winter for 2 seasons. After releases at the pond, B. affinis successfully reproduced and survived during the summer of 1992. Weevil larvae had damaged both sentinel and native tubers at the site. In the spring, following the release of B. affinis at the pond, a light trap and baited shelter traps were used to detect weevils that had overwintered naturally at the site. No weevils were recovered. At the Chowchilla River site, B. affinis failed to establish, possibly due to a lack of tubers in the section of the river where the releases were made.

Damage by Hypocala andremona (Cramer) (Lepidoptera: Noctuidae) larvae to Diospyros spp. (Ebenaceae) was observed on the U. S. Department of Agriculture, Subtropical Horticulture Research Station in Miami, Florida. The larvae caused severe damage to black sapote, D. digyna Jacq., and Japanese persimmon, D. kaki L. Damage was also observed on D. sonorae Standl. and D. texana Scheele. Percentage survival of H. andremona larvae ranged from 0% for D. montana Roxb. and D. mespiliformis Hochst. ex A. DC. to 64% for tender foliage of D. digyna. The larval stage lasted 19 d on tender foliage of D. digyna and 28-32 d for other Diospyros spp. No parasites emerged from H. andremona collected in the field. These results indicate that D. digyna was the most favorable of the hosts of H. andremona studied; however, tender foliage was necessary for early instars to complete development. Also, the importation of parasites of H. andremona might help reduce the equilibrium density of the pest.

Over 60 exotic Ficus (fig) species have been introduced into southern Florida as ornamentals. Three of these, F. altissima Blume, F. benghalensis L., and F. microcarpa L. are now weedy because they are pollinated routinely by immigrant agaonid wasps [Eupristina sp., Eupristina masoni Saunders, and Parapristina verticillata (Waterston) respectively]. Conditions for colonization by these wasps appear to have been met, and are potentially suitable for pollination of two other fig species. Four other immigrant wasp species (three pteromalids and a torymid) occupy the fruits of F. microcarpa and may interact with the pollinating wasps. Such interactions are more complex, but scarcely understood, in the native F. aurea Nuttall and F. citrifolia P. Miller, in which at least 10 and 14 species respectively of other animals occur routinely. These other animals include Hymenoptera (Torymidae, Eurytomidae, and Pteromalidae), Diptera (Cecidomyiidae), Coleoptera (Staphylinidae), Acarina (Tarsonemidae), and Nematoda (Diplogasteridae and Aphelenchoididae). Because of their potentially negative effect on agaonid populations, non-pollinating fig faunas should be examined to determine whether they may play a role in control of weedy figs.

A recent survey of Bermuda's Hymenoptera resulted in 88 new records. This brings the number of known species to 199, representing 28 families. Approximately 25% of the species are cosmopolitan or tropicopolitan. A further 37% are common to Bermuda and eastern North America, and 24% originate from the Caribbean region. Two species are known to be endemic; at least six species remain undescribed.

The Scelionidae is a large family of parasitic Hymenoptera whose members specialize in egg parasitism of insects and arachnids. Many of the characteristics considered most desirable in a natural enemy can be found within members of this family. Species have been studied which demonstrate high searching abilities and reproductive rates, lack of hyperparasitoids, have synchrony with host populations, have positive host-density responsiveness, have simple adult diets, and can be reared easily. The advancements made in rearing techniques for these natural enemies should prove valuable in the future both in classical biological control and in augmentative efforts. Research which has been done indicates that a variety of approaches are possible for augmenting scelionid populations. These range from simple innundative releases to manipulation of preferred nectar-bearing plants. Although fewer than 30 species have been used in classical biological control attempts, several of these have produced excellent results. The interaction of scelionid wasps with various insect management tactics is discussed. In general, scelionids interact well with insecticide applications due to the protective nature of host egg choria. The number of known scelionid species represents only a fraction of those estimated to be in existence. The results of biological control efforts undertaken with known species suggests that much potential exists within the Scelionidae.

DRAY, F. A., C. A. THOMPSON, D. H. HABECK, J. K. BALCIUNAS, AND T. D. CENTER. 1988. A survey of the fauna associated with Pistia stratiotes L. (waterlettuce) in Florida. Tech. Rpt. A-88-6, U.S. Army Engineer Waterways Experiment Station, Vicksburg, Mississippi. 37 pp. FORNO, I. W. 1983. Life history and biology of a waterhyacinth moth, Argyractis subornata (Lepidoptera: Pyralidae, Nymphulinae). Ann. Entomol. Soc. Am. 76: 624-627. HABECK, D. H. 1988. Neargyractis slossonalis (Lepidoptera: Pyralidae, Nymphulinae): larval description and biological notes. Florida Entomol. 71(4): 588592. MUNROE, E. G. 1972. Pyraloidea, Pyralidae (in part), fasc. 13.1A in R. B. Dominick, C. R. Edwards, D. C. Ferguson, J. G. Franclemont, R. W. Hodges, and E. G. Munroe (eds.), The moths of America north of Mexico. E. W. Classey, Ltd., London.

Trichospilus diatraeae Cherian and Margabandhu (Hymenoptera: Eulophidae) is an Asian parasite of the pupae of graminaceous stem borers [Chilo spp. and Sesamia spp. (Lepidoptera: Pyralidae)]. Consignments from India were shipped to the USA and to Trinidad in 1963 for laboratory trials against Diatraea spp. which are serious pests of sugarcane in the New World (Rao et al. 1971). Emergence from consignments to the USA, sent to the USDA-ARS, Beneficial Insects Introduction Laboratory, Moorestown, N.J., was very poor and no tests or releases were undertaken (R. Dysart, USDAARS-BIRL, Newark, DE, personal communication, 1986). In Trinidad choice tests with material from India, carried out under quarantine, indicated that adults of this gregarious parasite did not discriminate between Diatraea pupae and puparia of the beneficial tachinid flies Lixophaga diatraeae (Townsend) and Paratheresia claripalpis (Wulp) (Bennett 1965). Therefore, cultures were destroyed without making any field releases. Tests undertaken in Barbados in 1963-1964 confirmed the Trinidad results and no releases were made at that time. However, this parasite was again imported from India into Barbados in 1972 (Alam & Gibbs 1985) against other lepidopterous pests, including Spodoptera frugiperda (J. E. Smith) (Noctuidae). There were also reports (Cock 1985) of the introduction of a second species, Trichospilus pupivora Ferriere, against the same group of pests and this has lead to confusion as to which species is now present in Barbados. Establishment under the name T. pupivora was reported by Ingram (1981), Alam (1979), and Cock (1985), whereas Bennett and Alam (1985) listed the species as T. diatraeae and Alam and Gibbs (1985) also used this name. Both names represent valid species which are distinctive and can be readily separated (see Boucek 1976). In 1984, one of us (M.Y.) reared T. diatraeae from a noctuid pupa (possibly S. frugiperda) collected among rice stubble at Caroni, Trinidad. On May 3, 1985, one of us (H.G.) collected 48 pupae of Epimecis detexta (Walker), a geometrid pest of avocado, from a commercial grove in Dade Co., Florida; 2 of these yielded adults of T. diatraeae

Fall armyworm, Spodoptera frugiperda (J. E. Smith), larvae from Choluteca, Honduras and Starkville, Mississippi, U.S.A., were reared on sorghum or corn at 26 or 27@*C and 14 hours of light. Head capsule widths were measured to determine instar change. Larval development time was shorter for insects from Mississippi than insects from Honduras. No difference in development time for larvae in either culture was due to the host plant. The duration of prepupal and pupal stages was not significantly different for any of the treatments. Moths from Mississippi appeared to be more fecund than moths from Honduras, and insects fed corn appeared to be more fecund than those fed sorghum.

Microplitis croceipes (Cresson) is a larval parasite of both Heliothis zea (Boddie) and H. virescens (F.) (the bollworm complex) (Lewis & Brazzel 1968). In Arkansas, M. croceipes is the predominant parasite of Heliothis spp. particularly in late spring and early summer cotton fields (Burleigh 1975). In Integrated Cotton Pest Management systems the process of insecticide selection often does not consider the impact to beneficial insects. This is partly due to the lack of information about the susceptibility of specific predators and parasites to various insecticides. This study was undertaken to provide information on the susceptibility of M. croceipes to insecticide formulations used in cotton pest management. The same testing procedure was used throughout the study. A 5.5 cm diam filter paper disk was dipped into varying concentrations of insecticide, air dried for ca. 2 h and taped to the side of a 0.27 1 waxed paper cup. A moist cotton ball and a raisin were placed in the cup for food and water. Adult M. croceipes were aspirated into a cup which was covered with a lid. Mortality was recorded at 1, 16, 24 and 48 h. The insecticide concentration was based on recommended rates for Heliothis control in cotton using an application volume of 18.9 1 of water per 0.4 ha (Table 1). Concentrations used were 5, 3, and 2 times field rate, field rate, and dilutions of 1 part field rate to 5, 10, 50, 500, and 5000 parts water. The adult M. croceipes used in testing had not been exposed to Heliothis larvae and were less than 3 days old. No attempt was made to equalize the number of males and females exposed to any particular concentration of insecticide. When mortality occurred, the tests were repeated at insecticide concentrations above and below the concentration that caused mortality. Insecticide susceptibility testing was conducted on adult M. croceipes reared from Heliothis spp. larvae collected from cotton fields during the fall of 1983 and using adults from a laboratory colony during 1984-5. This colony was obtained from the Department of Entomology, University of Arkansas, Fayetteville. A total of 10 insecticides were tested using 391 adults. Insecticide susceptibility was evaluated by determining percent mortality at concentrations more than field rate, field rate, and less than field rate. Data were analyzed using a two way ANOVA, the combined concentration levels and the different insecticides were used as treatments. Only insecticides which caused mortality were included in the analysis. The results of the insecticide susceptibility tests are shown in Fig. 1. No mortality occurred in the controls during testing. The biological control agents, B. thutringiensis

Approximately 4,000 Trybliographa daci Weld. were received in 1977 from Dr. R. Pralavorio, Station de Zoologie et de Lutte Biologie, Institut National de la Recherche Agronomique, Antibes, France to establish a laboratory colony using Anastrepha suspensa (Loew) as a host. This species is Indo-Australasian in origin, most commonly using Dacus sp. as hosts. It was reared in the INRA laboratory on Ceratitis capitata (Weid.). During the period 1979-1981, 43,310 individuals were released in Dade County, FL. Although a considerable number of fruit samples have been taken from the release sites no recoveries were made until the summer of 1984. A sample of 500 Surinam cherries (Eugenia uniflora L.) collected on 18-V-84 at the Tropical Research and Education Center yielded 488 A. suspensa pupae from which 7 T. daci emerged. A sample of 55 cattleya guavas (Psidium littorale var. longipes (0. Berg) Fosb. collected at the same location on 17-VII-84 yielded 163 A. suspensa pupae from which 2 T. daci emerged. In addition, 4 males and 17 females were recovered from A. suspensa larvae that emerged from 10 Psidium guajava L. collected on 25-VII-85; 12 males, 2 females from the same host collected on 28-VIII-85; 1 female from the same host out of 4 P. guajava collected on 13-IX-85; and 10 males and 45 females were recovered from 479 A. suspensa larvae that had emerged from 10 P. guajava collected on 16-X-85, all from the same locality. Since no releases of T. daci were made after 1981, it apparently was able to survive at levels below that which we were able to detect with our sampling procedures. Based upon the recoveries reported here, we consider T. daci to be established in Dade County. We thank A. Menke, (Systematic Entomology Laboratory, IIBIII, USDA, Beltsville, Maryland) and G. Nordlander (Swedish University of Agricultural Sciences, Dept. of Plant Protection, Uppsala, Sweden) for the determinations and R. Dysart (USDA SEA-AR Beneficial Insects Research Laboratory, Newark, Del.) for quarantine assistance. Florida Agricultural Experiment Stations Journal Series No. 6986.

POE, S. L. 1973. Tomato pinworm, Keiferia lycopersicella (Walshingham) (Lepidoptera:Gelechiidae) in Florida. Fla. Dept. Agric. & Consumer Serv., Div. Plant Ind., Entomol. Cir. No. 131., 2 pp. SCHUSTER, D. J. & R. L. Burton. 1982. Rearing the tomato pinworm (Lepidoptera:Gelechiidae) in the laboratory. J. Econ. Entomol. 75: 1164-1165. SWANK, G. R. 1937. Tomato pin worm [Gnorimoschema lycopersicella (Busck)] in Florida. Florida Entomol. 20: 33-42. WALZ, A. J. 1948. Some studies on the life history of the tomato pinworm, Keiferia lycopersicella (Busck). MS thesis, Univ. of Calif., Berkeley. WEINBERG, H. L. & W. H. LANGE. 1980. Developmental rate and lower temperature threshold of the tomato pinworm. Environ. Entomol. 9: 245-246.