Diaprepes abbreviatus (L.) is a major pest of Florida citrus. Adult females lay eggs in masses sealed between leaves in the citrus canopy, and recently-hatched neonate larvae drop to the soil and feed on roots. The coccinellid species, Cycloneda sanguinea (L.), Harmoniaaxyridis Pallas, and Olla v-nigrum Mulsant, are generalist predators that consume a wide range of citrus pests, although they have not been observed preying on Diaprepes. We conducted experiments to determine whether these species would feed on Diaprepes egg masses and neonate larvae, and how an exclusive or partial diet of Diaprepes eggs would influence their development. The three predators responded very similarly in our tests. In laboratory assays, coccinellid larvae and adults readily consumed exposed Diaprepes eggs and neonates less than 48 h old; and coccinellid larvae preyed on 40% of intact egg masses laid between wax paper strips or citrus leaves, whereas adults preyed on 8.7%. In a greenhouse assay,coccinellid larvae located and preyed on 22.7% of intact egg masses laid between leaves on potted citrus trees. Although neonates might have relatively limited exposure to predation in the canopy before they drop to the soil, predation could be an important factor selecting for the timing of egg hatch, neonate escape from leaf envelopes, and neonate drop. The developmental assays indicate that Diaprepes eggs are less suitable prey for thesecoccinellid species than eggs of the flour moth, Ephestia kuhniella Zeller, but that they could be a highly acceptable component of a mixed diet. Our experiments indicate that these coccinellid species are potentially important predators of Diaprepes but the extent to which they contribute to the natural biological control of this weevil remains unknown.

Biological control programs of Maconellicoccus hirsutus (Green), in the Caribbean have relied on Japanese pumpkins and sprouted potatoes as hosts for rearing both the mealybug and its parasitoids. However, seasonal shortages of these substrates have necessitated that others be found with equal or better qualities for sustaining large mealybug populations. In this paper, we report experiments comparing mass-rearing M. hirsutus on acorn squash (Cucurbita pepo L. var. ‘Turbinata’), chayote (Sechium edule [Jacques]), and prickly pear, Opuntia ficus-indica [L.]) with Japanese pumpkin and sprouted potato. In addition, a simple meridic diet based on canned pumpkins was developed and compared. Acorn squash produced large quantities of females (up to 1,300 per squash) with a life cycle and reproductive potential equal to that of mealybugs reared on Japanese pumpkin. Parasitoids reared on these mealybugs developed normally and had a female-biased sex ratio similar to those reared on mealybugs on Japanese pumpkins or potato sprouts. Development of M. hirsutus reared on chayote and prickly pear was delayed by 1.5-5.0 days compared to that of mealybugs reared on Japanese pumpkins. Mealybugs on these substrates produced parasitoids with prolonged developmental times and male-biased sex ratios. On diet, development and reproduction of M. hirsutus was possible only for 3 to 4 consecutive generations. Mealybugs with longer developmental time, lower survival, and smaller ovisacs with lower percentage eclosion were obtained. Parasitoids reared from these mealybugs did not possess desirable characteristics for biological control. The developmental rate of adult parasitoids increased linearly with that of female hosts depending on the quality of the rearing substrate for the mealybugs.

Experiments in Costa Rica and Honduras determined that both Metamasius hemipterus L. and Rhynchophorus palmarum L. could be captured in the same trap using pheromone lures emitting a mixture of their male-produced aggregation pheromones. Mass trapping of both species was conductedin commercial palmito palm (Bactris gasipaes, Kunth) over 16 months using a combination lure and insecticide-laden sugarcane at a density of 4 traps/ha. Capture rates of M. hemipterus were initially high and declined significantly while capture rates of R. palmarum were initially low andremained relatively constant. Pupae found in and damage to palmito declined significantly in plots with traps compared to pre-trapping levels and to control plots without traps. Yields of palmito palm increased in all plots but increased most in plots with traps.

Frankliniella occidentalis (Pergande) (Thysanoptera: Thripidae), the western flower thrips, is the primary insect pest of tomatoes and other vegetable crops in northern Florida and the rest of the southeastern USA. However, it is not the only flower thrips present in the region nor is it always the most abundant species. To determine the seasonal and within plant distribution of these various Frankliniella species, experimental tomato plants, grown under different nitrogen fertilization regimes, were sampled during the fall and spring growing seasons. Contrary to expectations, different levels of nitrogen fertilization did not affect the abundance of thrips species. Thrips were much more abundant in the spring than in the fall. In the spring F. occidentalis was the most abundant species, while in the fall F. tritici (Fitch) was the most abundant species. In both the fall and spring, significantly more adults occurred in flowers in the upper part of the plant canopy than in flowers in the lower part of the plant canopy. The sex ratio tended to be female biased, but with a greater percentage of males occurring in the upper canopy flowers. In contrast, significantly more immature thrips occurred in the lower part of the plant canopy than in flowers in the upper part of the plant canopy. Differences in seasonal patterns and within plant distribution should be considered in developing sampling protocols and management plans for thrips.

In the Mediterranean fruit fly (medfly), Ceratitis capitata (Wiedemann), exposure to α-copaene, a botanically derived male attractant, and ginger root oil (GRO), Zingiber officinale (Roscoe), which contains α-copaene, increased the mating success of wild males, and GRO enhanced mating competitiveness of mass-reared males from a bisexual, mass-reared strain. The present study extends this research by examining the effects of GRO exposure on the mating success of mass-reared males from a genetic sexing strain based on a temperature sensitive lethal (tsl) mutation. Such strains are currently used for nearly all sterile insect technique (SIT) programs for this insect. In addition, potential negative effects of GRO exposure on male survival and female remating propensity were investigated. Following exposure to GRO, males from the tsl mass-reared strain showed enhanced mating performance against wild-like males from two recently established colonies. Against wild-like males from a Guatemala strain, the proportion of matings obtained by males from the tsl mass-reared strain increased from 16% per replicate for non-exposed (control) individuals to 30% for GRO-exposed (treated) individuals. Against wild-like males from a Madeira strain, the proportion of matings obtained by treated, tsl mass-reared males was 39% per replicate compared to only 16% for control, tsl mass-reared males. Survivorship was similar between GRO-exposed and non-exposed males from the tsl strain, and females mated initially to treated or control tsl mass-reared males displayed similar remating propensity. The application of pre-release, GRO-exposure to males in the SIT against medfly is discussed.

Seasonal abundance of the Asian citrus psyllid, Diaphorina citri Kuwayama, was studied weekly in two orange jasmine [Murraya paniculata (L.) Jack] plots in southern Florida from October 1998 to October 1999. Psyllid populations occur throughout the season on orange jasmine in southern Florida. Population peaks were observed in October, November, and December in 1998, and May and August in 1999. Psyllid population levels were positively related to the availability of new shoot flushes which were in turn related to the weekly minimum temperature and rainfall. Natural enemies were not key factors in regulating populations during the study period. The populations of adult psyllids were also studied weekly on potted orange jasmine and grapefruit (Citrus paradisi Macfadyen) plants from June 1999 to July 2000. The population levels of psyllid on both host plants were not significantly different and general population trends on the two hosts were similar over time. Continuous shoot flushes produced by orange jasmine could play an important role in maintaining high populations of this insect when new shoot flushes were not available in the commercial citrus groves.

Oviposition biology of Acanthocinus nodosus was examined on southern pine beetle (SPB), Dendroctonus frontalis, infested loblolly pine trees in Alabama, U.S.A. Components of oviposition biology, including oviposition pit description, colonization period, average number of eggs laid per oviposition pit, use of bark beetle entrance or ventilation holes as oviposition sites, and pit density were described. Acanthocinus nodosus oviposition pits were easily differentiated from Monochamus titillator, another cerambycid species that also inhabits SPB-killed trees. Colonization of trees by A. nodosus began within 2 days of initial SPB attack and lasted for 8 to 14 days. Females laid an average of 3.33 (SE ± 0.48) eggs per oviposition pit and 99% of the pits occurred on SPB entrance and ventilation holes. All pits were on the lower bole between 18 and 163 cm above the ground. Oviposition pit density ranged from 0.22 to 0.45 pits per cm² of bark surface. Potential interactions with other phloem inhabiting species were noted.

One method of evaluating the impact of insect weed biological control agents is to exclude them from their host with insecticides, thereby enabling comparisons of host fitness between infested and non-infested plants. However, the insecticide must not positively or negatively affect the plant being protected. The insecticide acephate was tested for its effects on Oxyops vitiosa Pascoe and Melaleuca quinquenervia (Cav.) S. T. Blake. Saplings of M. quinquenervia were sprayed with concentrations of 0, 0.073, 0.36, and 0.73% a.i. acephate every 7, 14, and 21 days. A bioassay using leaves from sprayed plants and third instars of O. vitiosa found reduced defoliation up to 21 days after treatment at the 0.36 and 0.73% concentrations of acephate. There were minor phytotoxic effects on younger, more tender leaves at the 0.73% concentration of acephate which reduced leaf biomass. Acephate can protect M. quinquenervia foliage from O. vitiosa larvae at the 0.36% concentration and spraying every 14 days will not affect the plant.

The life cycle of Pachycoris klugii on its native host, Cnidoscoulus multilobus (Euphorbiaceae), is reported in detail for the first time. Egg, nymphs, and adults are described and illustrated. Extensive variation was observed in the color pattern of adults. Maternal behavior was related to egg parasitism, habitat and host plant phenology. The tachinid fly Trichopoda pennipes was observed parasitizing adults and the scelionid wasp Telenomus pachycoris parasitized eggs of P. klugii.

Bemisia argentifolii (Powell & Bellows) (Homoptera: Aleyrodidae) (= B. tabaci Gennadius B biotype) nymphs reared on an artificial feeding system were successfully parasitized by three species of wasps, Encarsia formosa Gahan, Eretmocerus eremicus Rose and Zolnerwich, and Eretmocerus mundus Mercet (Hymenoptera: Aphelinidae). Encarsia formosa and Eretmocerus spp. preferred to parasitize third and fourth instar nymphs including the late fourth instar “red eye” stage. Oviposition rate and developmental time compared favorably to some reports on plants, but successful production of adult wasps was low. This system can be used to elucidate host-parasite interactions without confounding interactions with plants.

Wild strain, mated, female Mexican fruit flies, Anastrepha ludens (Loew), with no prior experience with fruit (naïve), were not attracted to and did not attempt oviposition in yellow chapote (Sargentia greggii) fruit more so than grapefruit (Citrus paradisi) in wind tunnel experiments. Naïve, mated laboratory strain females preferred grapefruit. Prior experience with chapote increased attraction of both laboratory and wild strains to chapote. More naïve than chapote-experienced females of both strains attempted to oviposit on the sides of the wind tunnel. Naïve laboratory strain males were more attracted to grapefruit than chapote. Naïve wild males and chapote-experienced wild and laboratory males did not prefer either fruit.

Cost is the principal constraint on the use of biological control against whiteflies in poinsettia (Euphorbia pulcherrima Willd. ex Koltz.) crops in the United States. Here we show that a new, lower release rate of the whitefly parasitoid Eretmocerus eremicus Rose and Zolnerowich (Hymenoptera: Aphelinidae), 0.5 females per plant per week, maintains whiteflies (Bemisia argentifolii Bellows and Perring) at harvest below the economic threshold of 2 live nymphs pupae per leaf, when used in combination with two mid-crop applications of the insect growth regulator fenoxycarb (Precision®). Cost of this program (for 16.5 cm dia single stem pots, with 30,000 plants under protection) varies from 21 to 34 cents per plant for the season, for cropping periods from 12 to 18 weeks. Shipping costs are calculated and included in estimated costs. These values compare favorably to the real cost of whitefly chemical control incurred by Massachusetts poinsettia growers in fall of 2000, which was 14 cents for a 16.5 cm dia single stem pot, with a range of 1 to 40 cents. Programs consisting of a single application of the systemic insecticide imidacloprid alone cost 12 cents per pot per season.This difference between 21 cents for the biological control program and 14 cents for the chemical control program is the smallest yet reported for biological control of whiteflies in poinsettia.

Foreign exploration for natural enemies of pink hibiscus mealybug, Maconellicoccus hirsutus, was conducted in Australia from 2000 to 2002. In Queensland, the predaceous beetle Cryptolaemus montrouzieri, the predaceous drosophilid fly, Cacoxenus perspicax and the encrytid parasitoid Gyranusoidea indica were recovered. In Western Australia and the Northern Territory a predatory noctuid, Mataeomera sp., an aphelinid parasitoid Coccophagus sp., and a probable encyrtid hyperparasitoid, Coccidoctonus sp. were reared from M. hirsutus on a native Hibiscus species. A field study was conducted from February 2000 to March 2002 in Sherwood, Queensland to document the seasonal phenology of M. hirsutus in its native habitat on its preferred host, Hibiscus rosa-sinensis. Populations of the mealybug stayed at or below detectable levels for most of the study with minor population peaks in the summer months.

Mites and nematodes associated with three subterranean termite species, Reticulitermes flavipes (Kollar), Reticulitermes virginicus (Banks), and Coptotermes formosanus Shiraki were studied. Mites belonging to 8 families were found associated with the three termite species. Australhypopus sp. (Acari: Acaridae) was the most common mite on R. flavipes and R. virginicus. Histiostoma formosana Phillipsen and Coppel (Acari: Acaridae) was the dominant mite species living on C. formosanus. Nematode, Rhabditis sp. (Rhabditida: Rhabditidae) was found in the three termite species examined. Nematodes did not cause termite mortality or abnormal behavior. Percentages of R. flavipes, R. virginicus, and C. formosanus parasitized by nematodes were 67.9, 38.8, and 3.3%, respectively. The nematodes were found mainly in the termite heads (85.8% in R. flavipes and R. virginicus). The abundance of mites varied with colonies and termite species. Australhypopus sp. occurred in large numbers when injured or dead termites are present, or when moisture of the rearing medium is low in R. flavipes and R. virginicus colonies. Histiostoma formosana and Cosmoglyphus absoloniSam i ák occurred in large numbers in C. formosanus colonies. Australhypopus sp. was tested against R. flavipes in the laboratory. It did not cause significant termite mortality at a rate of 10 mites/termite. From a biological point of view, mites investigated were not good candidates for controlling termites.

Rhynchophorus palmarum (L), the American palm weevil, is an important pest of several palm species in tropical America as a vector of the red ring nematode Bursaphelenchus cocophilus Cobb. Bimonthly inspections coupled with elimination of red ring diseased (RRD) oil palms (Elaeis guineensis Jacq.) failed to reduce infection rates of oil palms in two commercial plantations in Costa Rica. Addition of pheromone-based trapping of R. palmarum using trap densities of less than one trap per five hectares lowered RRD in both plantations by over 80% in one year. Continued removal of RRD infected palms and trapping maintained RRD at very low levels over several years. No matter what the initial RRD infection level, trap density or capture rate, areas with high and areas with low RRD infection levels declined to the same low RRD infection level after one year of trapping. An efficient strategy for management of RRD in oil palm is based on an integrated approach where RRD and other diseased (e.g., spear rot) palms are promptly eliminated or properly treated and pheromone-baited traps are used to reduce populations of R. palmarum. These strategies are complimented by removal of weevil-infested palms after wind and lightning damage and periodic removal of palms (e.g., coconut palms) in surrounding areas that serve as hosts for R. palmarum.