Xylosandrus Compactus Research Articles

Fungal Associates of the Xylosandrus compactus (Coleoptera: Curculionidae, Scolytinae) Are Spatially Segregated on the Insect Body.

Studies of symbioses have traditionally focused on explaining one-to-one interactions between organisms. In reality, symbioses are often much more dynamic. They can involve many interacting members, and change depending on context. In studies of the ambrosia symbiosis-the mutualism between wood borer beetles and fungi-two variables have introduced uncertainty when explaining interactions: imprecise symbiont identification, and disregard for anatomical complexity of the insects. The black twig borer, Xylosandrus compactus Eichhoff, is a globally invasive ambrosia beetle that infests >200 plant species. Despite many studies on this beetle, reports of its primary symbionts are conflicting. We sampled adult X. compactus and infested plant material in central Florida to characterize the fungal symbiont community using dilution series, beetle partitioning, and DNA-based identification. X. compactus was consistently associated with two fungal taxa, Fusarium spp. and Ambrosiella xylebori Multivariate analyses revealed that A. xylebori was strongly associated with the beetle mycangium while Fusarium spp. were associated with the abdomen and external surfaces. The Fusarium spp. carried by X. compactus are not members of the Ambrosia Fusarium Clade, and are probably not mutualists. Fungal community composition of the mycangium was less variable than external body surfaces, thus providing a more consistent fungal inoculum. This is the first report of spatial partitioning as a mechanism for maintenance of a multimember ambrosia fungus community. Our results provide an explanation for discrepancies among previous reports, and suggest that conflicting results are not due to differences in symbiont communities, but due to inconsistent and incomplete sampling.

New report of insect pests and their natural enemies in pomegranate

Different insect pests and their natural enemies got identified and reported for the first time in pomegranate. Among the borer pests, shot hole borer (Xylosandrus compactus) and hairy caterpillars (Olene mendosa, Somena scintillans and Euproctis fraterna) have been reported for the first time in pomegranate. Gummosis has also been reported for the first time in pomegranate on 5 to 10 per cent plant from orchards in Solapur and Sangli districts of Maharashtra. A new species of shot hole borer, X. compactus was suspected to be associated with gummosis for which, confirmatory tests could be carried out to find out its role for its effective control. Among sucking pests, vine mealybug, Planococcus ficus, Cottony cushion scale, Icerya aegyptiaca, and Brown soft scale, Coccus hesperidium are first report on pomegranate from Maharashtra.

The formicid ant, Plagiolepis sp., as a predator of the coffee twig borer, Xylosandrus compactus

The coffee twig borer (Xylosandrus compactus Eichhoff) is an economically important pest of Robusta coffee in Uganda. In this study, a formicid ant, Plagiolepis sp., found in X. compactus galleries at the National Coffee Research Institute in 2014, was evaluated for potential to provide biological control of the twig borer. In a Petri dish feeding bioassay, Plagiolepis sp. preyed on all stages of X. compactus except adults within 24h. In field bioassays where Plagiolepis sp. was caged over X. compactus-infested twigs for one month in muslin sleeves, the predator colonized pest galleries and eliminated all life stages of X. compactus as opposed to the untreated control. In a survey of Plagiolepis sp. in 11 districts of eastern, central and western Uganda, the ant was present in nine of the districts with highest levels of colonization (over 18%) of X. compactus galleries in Luwero district in the central Lake Victoria crescent agroecological zone. These results appear to confirm that Plagiolepis sp. is an indigenous predator of X. compactus which invades pest galleries and feeds on the pest in the field. For prospective utilization of Plagiolepis sp. as a biological control agent of X. compactus, studies on the biology of Plagiolepis sp., its mass rearing protocols and factors favoring its proliferation in the field are highly recommended.

English

Black coffee twig borer is a new but rapidly spreading insect pest of coffee in Uganda. Female beetles bore into primary branches/twigs and cultivate an ambrosia fungus for feeding their larvae. Thus, controlling the fungus means depriving the brood a source of food. Three fungicides, chlorothalonil (Glider), tebuconazole (Orius 25EW) and dimethomorph + mancozeb (Volar) were evaluated in vitro for their effectiveness in inhibiting mycelial growth of ambrosia fungus associated with the beetle. The pathogen was exposed to four concentrations (1.5x, 1.25x, 1.0x and 0.5x times the manufacturer recommended rate) incorporated into potato dextrose agar using inhibition and food poisoning techniques. The three fungicides inhibited fungal growth to some extent, even at the lowest concentration (0.5x) and percentage inhibition was significantly different (P≤0.05) from each other. Tebucozanole caused 100% growth inhibition irrespective of concentration and technique used while chlorothalonil and dimethomorph + mancozeb caused less than 40% inhibition for both techniques. Therefore, research should determine effectiveness of tebucozanole for suppressing fungal growth under field conditions for diminishing beetle incidence and fungal pathogenic effects in infested branches. This will pave way for integration of use of tebucozanole into overall Integrated Pest Management package (IPM) for the beetle in Uganda.    Key words:       Ambrosia-fungus, black-coffee-twig-borer, chlorothalonil, dimethomorph + mancozeb, fungicides, tebuconazole, Xylosandrus-compactus.

Ecology, Biology, and Management of Xylosandrus compactus (Coleoptera: Curculionidae: Scolytinae) with Emphasis on Coffee in Hawaii

The black twig borer, Xylosandrus compactus (Eichhoff) (Coleoptera: Curculionidae: Scolytinae) attacks >200 species of plants. This ambrosia beetle occurs on all the major islands of Hawaii and is a threat to some native plants and coffee plantations. Female beetles bore entry holes and excavate tunnels inside branches, which are inoculated with fungus to provide a food source for larvae. Two types of damages are described—1) superficial boring limited to the phloem and 2) cutting of the vascular tissue which subsequently reach the pith of the stem to make galleries. In this article, we discuss the life cycle, biology, plant damage characteristics, and management alternatives of X. compactus , focusing on coffee plants.

Variation in Effects of Conophthorin on Catches of Ambrosia Beetles (Coleoptera: Curculionidae: Scolytinae) in Ethanol-Baited Traps in the United States.

In 2013, we examined the effects of conophthorin on flight responses of ambrosia beetles (Coleoptera: Curculionidae: Scolytinae) to multiple-funnel traps baited with ethanol in Georgia, Michigan, New Hampshire, and Oregon. Adventive species (=exotic, nonnative, immigrant, introduced) accounted for 91.4% of total catches of ambrosia beetles. Conophthorin increased catches of Xyleborinus saxesenii (Ratzeburg) in Georgia, New Hampshire, and Oregon. Catches of Cyclorhipidion pelliculosum (Eichhoff) were increased by conophthorin in New Hampshire but not in Michigan. In Oregon, conophthorin decreased catches of Xylosandrus germanus (Blandford) to ethanol-baited traps but not in Michigan and New Hampshire. In Georgia, conophthorin increased catches of Gnathotrichus materiarius (Fitch), Xyleborus spp., and Xylosandrus crassiusculus (Motschulsky) but decreased catches of Cnestus mutilatus (Blandford), Dryoxylon onoharaensum (Murayama), and Cyclorhipidion bodoanum (Reitter). Conophthorin had no effect on catches of Ambrosiophilus atratus (Eichhoff), Anisandrus dispar (F.), Anisandrus sayi (Hopkins), Gnathotrichus sulcatus (Leconte), Monarthrum fasciatum (Say), Monarthrum mali (Fitch), and Xylosandrus compactus (Eichhoff). Attraction of the bark beetle, Hypothenemus rotundicollis (Eichhoff), was interrupted by conophthorin in Georgia. Our results suggest that adding conophthorin lures to traps baited with ethanol may have utility in detection programs in North America and overseas. However, traps baited with ethanol alone should also be used due to interruption in attraction for some species of ambrosia beetles.

Alternative preservatives of insect DNA for citizen science and other low-cost applications

Prevention of DNA degradation is essential to conducting molecular analyses of field-captured specimens. This is especially important for projects that incorporate participation of non-specialists in research, such as agency monitoring of pests, or citizen science, where standard methods of preservation may be inaccessible. We examined efficacy of three common alternative products as a substitute for 95% ethanol or pure propylene glycol in preserving DNA: alcohol-based hand sanitiser and propylene and ethylene glycol-based automobile antifreeze. We subjected Xylosandrus compactus ambrosia beetles (Coleoptera : Curculionidae : Scolytinae) to each preservative for two or seven days under direct outdoor exposure and assessed relative quantity of intact DNA by performing real-time polymerase chain reaction amplification of a single-copy nuclear marker. Amplification was observed in all treatments and electrophoresis of the amplified product showed clear bands of the appropriate weight. Successful amplification of the target gene was verified by sequencing the amplified control. No statistically significant differences were found between the cycle threshold values of any treatment. Our results suggest that alcohol-based hand sanitiser and automobile antifreeze can successfully preserve DNA for short-term storage and serve as effective substitutes for laboratory-grade preservatives in citizen science projects, large-scale trapping projects or by professionals.

Dispersion and Sequential Sampling Plan forXylosandrus compactus(Coleoptera: Curculionidae) Infesting Hawaii Coffee Plantations

The black twig borer, Xylosandrus compactus (Eichhoff) (Coleoptera: Curculionidae: Scolytinae), is a serious pest of coffee (Coffea arabica L.) in the Kona region of the island of Hawaii, the center of the largest area of coffee production within the state of Hawaii. This study indirectly characterizes the spatial distribution of X. compactus in coffee plantations through assessment of twig borer damage, and presents a sequential sampling plan for monitoring X. compactus population densities. Taylor's Power Law (TPL) and Iwao's mean crowding index showed that X. compactus infestations were highly aggregated within plantations, with b and ß values significantly larger than 1. The TPL linear regression of log variance against log mean (R2 = 0.92) provided a better fit to the data than the linear regression of mean crowding on the mean (R2 = 0.68). Subsequently, Taylor's power law parameters were used to develop the Green's sequential plan to estimate densities of X. compactus at the 90 and 75% precision levels.

SEVERE OUTBREAK OF FUSARIUM SOLANI ON QUERCUS ILEX VECTORED BY XYLOSANDRUS COMPACTUS

The black twig borer Xylosandrus compactus (Eichhoff) (Coleoptera: Scolytinae) causes severe damages to its hosts (Chong et al., 2011) because it also vectors Fusarium solani, which induces wilting of twigs and terminal branches (Ngoan et al., 1976). In two urban parks in Naples and Portici (southern Italy) an evident flagging of the leaves of holm oak (Quercus ilex) was observed, followed by a rapid wilting of shoots and twigs of saplings and mature trees (Garonna et al., 2012). A fungus isolat- ed from the beetle’s reproductive galleries, entry holes and the adjacent black-stained woody tissues, was grown on potato dex- trose agar (PDA) at 25°C, and identified by sequencing the ITS 1-4 region of rDNA. The sequence showed 99% identity with that of Fusarium solani from GenBank (accession No. EU719658.1). In pathogenicity tests, holm oak branches were in- oculated with a 2-mm PDA dish collected from a 7-day-old cul- ture of the F. solani isolate (FS1). Control branches were inocu- lated with plugs of sterile PDA. All branches were incubated at 25±1°C. After five days, symptoms resembling those exhibited by naturally infected plants developed only on the branches inocu- lated with FS1, from whose tissues this fungus was re-isolated, thus proving to be a Q. ilex pathogen. Symptoms recalling those observed in the two sites surveyed are spreading through the holm oak woodlands of Campania (southern Italy), so the geo- graphical distribution of the outbreak may already be consider- able. To the best of our knowledge this represents the first Euro- pean record of a severe outbreak of F. solani on Q. ilex following a massive attack by X. compactus.

First record of the black twig borer Xylosandrus compactus (Eichhoff) (Coleoptera: Curculionidae, Scolytinae) from Europe

During winter months and early spring 2011, we observed symptoms of scattered twig mortality in two historical woody urban parks of Campania (Southern Italy), at Portici (Parco Gussone: 40°48’ N, 14°20’ E) and Naples (Parco di Capodimonte: 40°52’ N, 14°15’ E). The woods consist of mature holm oaks (Quercus ilex) with an understorey of evergreen Mediterranean shrubs, natural regeneration of oak and several ornamental species. The examined dry terminals of holm oak, collected in late March 2011, hosted adult females of an ambrosia beetle of the genus Xylosandrus Reitter. Here, we report the first European record of the black twig borer (BTB) Xylosandrus compactus (Eichhoff) reproducing on new host plants in Italy. Insect and twig sampling was conducted irregularly during spring and summer 2011. Infested twigs of different host plants were isolated in plastic tubes, new emerged or callow adults counted and sexed and other biological data recorded. Hundreds of specimens of BTB, (>700 females and 43 males) emerged from sampled twigs or were directly collected from reproductive galleries at both localities.

Efficacy of Traps, Lures, and Repellents for Xylosandrus compactus (Coleoptera: Curculionidae) and Other Ambrosia Beetles on Coffea arabica Plantations and Acacia koa Nurseries in Hawaii

The black twig borer, Xylosandrus compactus (Eichhoff) (Coleoptera: Curculionidae: Scolytinae), is a pest of coffee and many endemic Hawaiian plants. Traps baited with chemical attractants commonly are used to capture ambrosia beetles for purposes of monitoring, studying population dynamics, predicting outbreaks, and mass trapping to reduce damage. The objectives of this research were to optimize trapping systems for X. compactus and other ambrosia beetles such as Xylosandrus crassiusculus (Motschulsky) and Xyleborinus saxesenii (Ratzeburg) by comparing efficacy of several attractants, repellents, and trap types. The ability of certain chemicals to act as beetle repellents and thus interfere with trap catch was tested for purposes of protecting host plants from attack. Potential attractants and application methods tested were as follows: ethyl alcohol pouch delivery system, ethyl alcohol vial delivery system, α-pinene in Eppendorf tubes, eugenol bubblecaps, ginger oil bubblecaps, manuka oil bubblecaps, phoebe oil bubblecaps, and an unbaited control. Potential repellents tested were limonene and verbenone. Ethyl alcohol vials were as attractive as ethyl alcohol sleeves, and were more effective than traps baited with eugenol and α-pinene. Japanese beetle traps were more effective for black twig borer trapping than Lindgren funnel traps, and were easier to deploy. Verbenone and limonene significantly reduced trap catch of Xylosandrus compactus and X. crassiusculus, suggesting that they may be effective for reducing attraction to host plants. These results show the importance of developing a combination of several monitoring techniques to enhance management procedures for the black twig borer.

Susceptibility to Laurel Wilt and Disease Incidence in Two Rare Plant Species, Pondberry and Pondspice.

Laurel wilt, caused by Raffaelea lauricola, has been responsible for extensive losses of redbay (Persea borbonia) in South Carolina and Georgia since 2003. Symptoms of the disease have been noted in other species of the Lauraceae such as the federally endangered pondberry (Lindera melissifolia) and the threatened pondspice (Litsea aestivalis). Pondberry and pondspice seedlings were inoculated with R. lauricola from redbay, and both species proved highly susceptible to laurel wilt. Field assessments found substantial mortality of pondberry and pondspice, but in many cases the losses were not attributable to laurel wilt. R. lauricola was isolated from only 4 of 29 symptomatic pondberry plants at one site, but the fungus was not recovered from three plants at another site. R. lauricola was isolated from one of two symptomatic pondspice plants at one site, and from five of 11 plants at another site, but not from any plant at a third site. Insect bore holes, similar to those produced by Xyleborus glabratus (the vector of laurel wilt), were found in some pondberry and pondspice stems, but adults were not found. Damage caused by Xylosandrus compactus was found in pondberry stems, but this ambrosia beetle does not appear to be a vector of R. lauricola. Xyleborinus saxeseni adults were found in a dying pondspice with laurel wilt, and R. lauricola was recovered from two of three adults. Isolates of R. lauricola from pondberry, pondspice, and X. saxeseni had rDNA sequences that were identical to previously characterized isolates, and inoculation tests confirmed that they were pathogenic to redbay. Because pondberry and pondspice tend to be shrubby plants with small stem diameters, these species may not be frequently attacked by X. glabratus unless in close proximity to larger diameter redbay.

Distribution, Host Plants, and Damage of the Black Twig Borer, Xylosandrus compactus (Eichhoff), in South Carolina

The black twig borer, Xylosandrus compactus (Eichhoff) (Coleoptera: Curculionidae: Scolytinae), is an exotic ambrosia beetle that can be a severe pest of ornamental trees and shrubs in the landscape of South Carolina. This paper reports on the beetle's distribution and host plants in South Carolina. Descriptive data on the severity of attacks in different locations and at specific heights of southern magnolia (Magnolia grandiflora L.) trees were also gathered. Xylosandrus compactus was trapped or observed in 18 counties in South Carolina, from the Atlantic Coast to the upper Piedmont regions. The recorded ornamental host plants of X. compactus in South Carolina include Buxus sempervirens L. (boxwood), Cercis canadensis L. (eastern redbud), Cornus florida L. (flowering dogwood), Ficus carica L. (common fig), Gardenia jasminoides J. Ellis (gardenia), Hydrangea macro- phylla (Thunb.) Ser. (hydrangea), Magnolia grandiflora, Morella (5 Myrica) cerifera (L.) Small (wax myrtle), and Pinus sp. (pine). On average, 47% of southern magnolia trees in seven neighborhoods of North Myrtle Beach, SC suffered attacks by X. compactus. Southern magnolia terminals at a height of 0-1 m (from soil surface) suffered the highest percentage of attacks (11.1%), followed by those at 1-2 m (7.2%). The percentage of terminals attacked was reduced to less than 4% at 3-6 m. The tendency for X. compactus to infest terminals at heights less than two meters suggests that preventive insecticide applications should target the lower branches to reduce damage.

Ethanol and (−)-α-Pinene: Attractant Kairomones for Bark and Ambrosia Beetles in the Southeastern US

In 2002-2004, we examined the flight responses of 49 species of native and exotic bark and ambrosia beetles (Coleoptera: Scolytidae and Platypodidae) to traps baited with ethanol and/or (-)-alpha-pinene in the southeastern US. Eight field trials were conducted in mature pine stands in Alabama, Florida, Georgia, North Carolina, and South Carolina. Funnel traps baited with ethanol lures (release rate, about 0.6 g/day at 25-28 degrees C) were attractive to ten species of ambrosia beetles (Ambrosiodmus tachygraphus, Anisandrus sayi, Dryoxylon onoharaensum, Monarthrum mali, Xyleborinus saxesenii, Xyleborus affinis, Xyleborus ferrugineus, Xylosandrus compactus, Xylosandrus crassiusculus, and Xylosandrus germanus) and two species of bark beetles (Cryptocarenus heveae and Hypothenemus sp.). Traps baited with (-)-alpha-pinene lures (release rate, 2-6 g/day at 25-28 degrees C) were attractive to five bark beetle species (Dendroctonus terebrans, Hylastes porculus, Hylastes salebrosus, Hylastes tenuis, and Ips grandicollis) and one platypodid ambrosia beetle species (Myoplatypus flavicornis). Ethanol enhanced responses of some species (Xyleborus pubescens, H. porculus, H. salebrosus, H. tenuis, and Pityophthorus cariniceps) to traps baited with (-)-alpha-pinene in some locations. (-)-alpha-Pinene interrupted the response of some ambrosia beetle species to traps baited with ethanol, but only the response of D. onoharaensum was interrupted consistently at most locations. Of 23 species of ambrosia beetles captured in our field trials, nine were exotic and accounted for 70-97% of total catches of ambrosia beetles. Our results provide support for the continued use of separate traps baited with ethanol alone and ethanol with (-)-alpha-pinene to detect and monitor common bark and ambrosia beetles from the southeastern region of the US.

—New diseases and pest occurred on golden-chain: Root rot caused by Rhizoctonia sp., Cylindrocladium sp. and Fusarium solani-complex, and dieback caused by Xylosandrus compactus (Castanopsis ambrosia beetle) and/or Phomopsis sp.

&#8212;New diseases and pest occurred on golden-chain: Root rot caused by <i>Rhizoctonia</i> sp., <i>Cylindrocladium</i> sp. and <i>Fusarium solani</i>-complex, and dieback caused by <i>Xylosandrus compactus</I> (Castanopsis ambrosia beetle) and/or <i>Phomopsis</i> sp.

Preferência de vôo de nove espécies da família scolytidae (Insecta: Coleoptera) na Amazônia Central1

Neste trabalho foi avaliada a preferência por altura de vôo de nove espécies da família Scolytidae, capturadas com armadilhas Escolitídeo/Curitiba e Marques/Carrano/Abreu, instaladas a 1; 3; 5; 7,5 e 10m de altura na Reserva Florestal Adolpho Ducke, no km 22 da rodovia AM-010 (Manaus, AM). Para isto foi feita uma análise de variância e as médias comparadas pelo teste de Tukey. O resultado das análises mostraram que, independente da armadilha utilizada, Xyleborus affinis Eichhoff, Xyleborus sp. 1 e Monarthrum sp. 1 apresentaram preferência de vôo por alturas inferiores a 3m; Cryptocarenus heveae (Hagedorn) mostrou preferência por alturas superiores a 5m; e Hypothenemus obscurus Fabricius acima de 7,5m; Xylosandrus compactus Eichhoff não apresentou preferência por qualquer altura de vôo. Cryptocarenus diadematus Eggers, Hypothenemus eruditus Westwood e Premnobius cavipennis Eichhoff apresentaram divergência quanto à tendência de vôo, em relação às armadilhas utilizadas.

Análise das principais espécies de Scolytidae coletadas em floresta primária no estado do Amazonas

Em área de floresta primária da Reserva Florestal Adolpho Ducke, foi feito o levantamento da ocorrência de insetos da família Scolytidae (Coleoptera), utilizando-se as armadilhas Escolitídeo/Curitiba e Marques/Carrano/Abreu, instaladas em alturas de 1m; 3 m; 5 m; 7,5 m e 10 m. Os dados de coleta foram avaliados quantitativa e qualitativamente. Dos 7.974 escolitídeos coletados, 4.131 (51,8%) o foram com a armadilha Escolitídeo/Curitíba e 3.843 (48,2 %) com a Marques/Carrano. Os dados revelam a existência de 14 gêneros e 168 espécies. O gênero Xyleborus foi responsável por mais de 50% das coletas e as principais espécies capturadas foram: Xyleborus affinis Eichhoff, que predominou durante o período do experimento, Xyleborus sp1, Premnobius cavipennis Eichhoff, Cryptocarenus heveae (Hagedorn), Cryptocarenus diadematus Eggers, Monarthrum sp1, Hypothenemus eruditus Westwood, Hypothenemus obscurus Fabricius e Xylosandrus compactus Eichhoff.

Insect succession on three coffee typs in Ghana

The experiment was conducted for a 7-year period (198188) at Tafo, Ghana on three newly-established coffee plots of a local variety (Coffea canephora) and two introduced vari~ties (c. canephora and C. arabica). Insect counts were made weekly on 50 randomly selected plants of each coffee variety. Among the insects recorded during the 1st year of establishment were three economically important pests viz. the defoliators (Epicampoptera strandi glauca Hamps., E. ivoirensis Watson), the grasshopper (Zonocerus variegatus Linnaeus) and the leaf skeletonizer (Leucoplema dohertyi Warren). Three other economically-important pests, the stem borer (Bixadus sie';ricolaWhite), the twig borer (Xylosandrus compactus Eichh.) and the berry borers (Hypothenemus hampei Ferrari) were not found throughout the 7-year experimental period. The biting ants (Oe{:ophylla longinoda Latr., Crematogaster africana Mayr and C. clariventris Mayr) which constitute a great nuisance during harvesting, weeding and other farm operations, were not found until the 6th year after establishment. The ants (G. olivieri. P. megacephala and C. vividus), the mealybug (Planococcoides njalensis (Laign» and Stictococcidae were the most numerous insects recorded on all three coffee types, especially during the 4th and 5th years of establishment. Aphids, psyllids, crickets, spiders, grasshoppers, among other insects, reduced in numbers or were absent during a severe and prolonged drought period in 1983-84. It was concluded that findings from the study could serve as a useful guidance to coffee farmers in Ghana, and perhaps other producer countries in the West African ,sub-region, regarding which insect pests to expd:t during the early years of establishment.

Chlorpyrifos Sprays for Control of Xylosandrus compactus in Flowering Dogwood123

Initial studies with chlorpyrifos applied at a rate of 2.4g/liter water (2 lb AI/100 gal water) with a hand sprayer on individual flowering dogwood twigs infested with Xylosandrus compactus (Eichhoft) resulted in 70% mortality of all beetle stages. In further field tests, hydraulic sprays of chlorpyrifos at 0.6, 1.2, 2.4, or 4.8g AI/liter water (0.5, 1.0, 2.0, and 4.0 lb AI/100 gal water) gave 83, 80, 93, and 92% mortality of all beetle stages/infested twig, respectively, while the corresponding check mortality was 19%. Mortality was not significantly different among the 4 insecticide rates.

Biology of an Introduced Ambrosia Beetle, Xylosandrus compactus,1 in Florida2

Xylosandrus compactus (Eichhoff), an introduced ambrosia beetle, is established in at least 28 counties in Florida and has been reported from southeast Georgia. The fungal symbiont was identified as Fusarium solani (Mart.) Sacc. The chaetal pattern of the head capsule is described. Average duration of the egg, larval, pupal, and adult maturation stages at room temperature was 5, 7.5, 7.5, and 8.5 days, respectively. Thirty-one plant species served as hosts of X. compactus in Florida. On flowering dogwood ( Cornus florida L.) X. compactus overwintered principally as adults in twigs and small branches, began emergence during late February, began attacks on new twigs during March, and began producing brood during April. Highest population levels in flowering dogwood twigs occurred from June through September.