Phoracantha Semipunctata Research Articles

Biological Constraints on Host-Range Expansion by the Wood-Boring Beetle Phoracantha semipunctata (Coleoptera: Cerambycidae)

The eucalyptus longhorned borer, Phoracantha semipunctata F., is a cosmopolitan pest of Eucalyptus. The developing larvae damage trees by boring through the outer bark and along the cambium layer. Although the borer has become established in many parts of the world where it has encountered novel host-plant species, it has restricted its attacks to Eucalyptus and a few closely related species. The goal of this study was to investigate the behavioral and ecological barriers to host-range expansion by P. semipunctata. In laboratory experiments, gravid female P. semipunctata showed a low propensity to oviposit on logs of nine novel host species even though they had been deprived of their natural oviposition hosts. Survivorship of neonate larvae artificially introduced into logs of some novel host species was similar to that of larvae in Eucalyptus logs. However, larval development time in these novel hosts was greatly prolonged and adult body size was reduced. These findings suggest that oviposition behaviors of the adult beetles could restrict the host range of P. semipunctata to Eucalyptus species, and that oviposition preferences correspond well with performance of the larvae.

Variation among Eucalyptus species in resistance to eucalyptus longhorned borer in Southern California

AbstractEucalyptus L'Héritier (Myrtaceae: Leptospermoideae) species are native to the Austro‐Malaysian region, but have been widely planted in temperate and subtropical regions around the world. In most regions where Eucalyptus have been imported, the Eucalyptus Longhorned Borer (Phoracantha semipunctata F.) (Coleoptera: Cerambycidae) has been accidently introduced. Larvae of the beetle bore through the bark and mine along the cambium of stressed trees, usually killing their host. We report here the relative susceptibilities of 12 Eucalyptus species in two mixed‐species plantations in California, USA. These trees were stressed by water deficit resulting from a prolonged drought. Eucalyptus species that appeared resistant to the borer included E. camaldulensis Dehnhardt, E. cladocalyx F. Muller, E. sideroxylon A. Cunn. ex Woolls, and E. trabutii (an E. camaldulensis hybrid). Species that were more susceptible to attack were E. diversicolor F. Mueller, E. globulus LaBillardière, E. grandis Hill ex Maiden, E. nitens (Deane & Maiden), E. saligna Sm., and E. viminalis LaBillardière. Survival of trees was influenced by fine‐scale moisture variation resulting from slope and irrigation effects. Resistance characteristics of these Eucalyptus species did not correlate with taxonomic relatedness or bark characteristics, but did correspond to drought tolerance traits in their native habitat. Eucalyptus species that were resistant to attack by P. semipunctata were those that are most tolerant of drought in Australia.

Integrated program protects trees from eucalyptus longhorned borer

Phoracantha semipunctata F., a cerambycid beetle introduced into California within the last 10 years, is killing large numbers of eucalyptus trees throughout much of the state. Risk of tree mortality can be reduced through managing tree stress, selection of more resistant tree species and disposal of infested wood. A biological control program to reduce beetle populations through the introduction of egg and larval parasites is currently being implemented. The combination of appropriate tree management and biological control holds promise for protecting these valuable ornamental tree species.

Phoracantha semipunctata (Coleoptera: Cerambycidae), a Serious Pest of Eucalyptus in California: Biology and Laboratory-Rearing Procedures

Procedures are described for establishing a laboratory colony of the eucalyptus longhorned borer, Phoracantha semipunctata F., and rearing the adult beetles on a continual basis. Adult beetles reared from naturally infested Eucalyptus logs were caged and provided with oviposition substrates (folded sheets of plastic). Techniques for handling and caring for eggs and neonate larvae are discussed. Larvae were individually transferred into shallow incisions in the bark of fresh logs. Total survivorship from neonate larvae to adult was ≈35%. Our procedures yielded an average of 63 adult progeny for every adult female, with a generation time of ≈2 mo during the summer. Beetle colonies were protected from pyemotid mites by dusting rearing logs with sulfur and from ants with granular diazinon. An experiment on adult beetle diet showed that the provision of sucrose water greatly increased longevity and fecundity over a distilled water control, but increasing the concentration of sucrose >5% did not significantly improve beetle performance.

Studies on egg predation by ants (Hymenoptera: Formicidae) especially on the eucalyptus borer Phoracantha semipunctata (Coleoptera: Cerambycidae) in Portugal

AbstractIridomyrmex humilis (Mayr) and some other ants, through preference, efficient foraging and recruitment, quickly removed artificially exposed batches of insect eggs including those of the serious pest of eucalyptus, Phoracantha semipunctata (Fabricius). This supports evidence of the importance of some ants as predators of the many insects that lay freely exposed eggs. However, P. semipunctata normally lays eggs in peeling bark crevices where the approximately 60% laid within gaps less than ca. 0.65 mm wide could not be reached even by small ants such as I. humilis and Pheidole pallidula (Nyland-er). In tree trunks, which can become heavily infested after felling, egg predation by ants seems unimportant compared with the later large mortality of competing larvae, so, egg predation cannot account for the observed striking positive correlation between presence of I. humilis and lack of Phoracantha semipunctata damage to standing trees. Egg predation and other effects of I. humilis may be more important on living trees which are attacked initially by relatively few P. semipunctata. This needs more detailed investigation as do the overall egg predatory roles of ant species in biological control.

Control of the straw itch mite (Acari: Pyemotidae) with sulfur in an insect rearing facility.

The ectoparasitic mite Pyemotes tritici (Lagrèze-Fossat & Montané) (Acari: Pyemotidae) caused paralysis and reduced longevity in eucalyptus longhorned borer, Phoracantha semipunctata F., under laboratory rearing conditions. Application of dusting sulfur to logs that contained pupating borers greatly reduced densities of mites on emerging adult beetles and increased beetle survivorship. Uniform application to all logs in a glasshouse effectively eradicated the mite infestation. A bioassay showed that sulfur may physically impede the dispersal of immature mites by adhering to the cuticle, but sulfur vapor did not act as a toxin.

Evaluation of Cold Temperatures and Density as Mortality Factors of the Eucalyptus Longhorned Borer (Coleoptera: Cerambycidae) in California

It was hypothesized that the northward spread of the eucalyptus longhorned borer, Phoracantha semipunctata F., in California is limited by winter temperature conditions. The cold tolerance of prepupal stages was tested by exposing infested logs to cold temperature treatments of −5,0, +5, and +10°C for periods of 1, 3, 7, and 30 d. Temperature treatments had no affect on survivorship to adulthood or longevity but did reduce adult weight relative to nontreated control logs. Increasing exposure time to all cold temperatures significantly reduced both survivorship and adult weight but had no affect on adult longevity. Long periods of exposure to cold temperatures delayed emergence of adults and resulted in more closely synchronized emergence. Cold temperatures are unlikely to prevent the spread of this pest into most zones occupied by its eucalyptus host plants. In addition, increasing densities of prepupae in logs also resulted in significantly reduced survivorship to adulthood but did not affect adult weight or longevity.

Mechanisms of Resistance in Eucalyptus Against Larvae of the Eucalyptus Longhorned Borer (Coleoptera: Cerambycidae)

First instars of the eucalyptus longhorned borer, Phoracantha semipunctata (F.), were not capable of colonizing bark of vigorous standing trees of two Eucalyptus species. The lack of a kino gum reaction after the introduction of larvae into the bark of E. grandis Hill ex Maiden and E. tereticornis Small strongly indicates that this gum does not play an important role in the initial defense against borer attack. Larvae were also not able to colonize the bark of logs that were maintained at high moisture content but were able to colonize the bark of dry logs and artificially water-stressed trees that had reduced bark moisture content. We propose that bark moisture content plays a critical role in the resistance of eucalyptus trees against colonization by eucalyptus longhorned borer larvae.

Efficacy and Economics of Selected Systemic Insecticides for Control of Phoracantha semipunctata (Coleoptera: Cerambycidae), a New Pest in North America

A eucalyptus longhorned borer (ELHB), Phoracantha semipunctata (F.), was first found infesting eucalyptus trees in southern California late in 1984. Studies were conducted in summer and fall 1986 and winter and spring 1987 on woodlot (WL) and windbreak (WB) settings to determine the efficacy and economics of soil- and trunk-injected systemic insecticides for managing this pest. None of the materials investigated (acephate, carbofuran, disulfoton, and oxydemeton-methyl) provided acceptable control. In addition, the relatively high application costs per tree (1986, $7.74 WL and 11.09 WB; 1987, $6.03 WL and $7.63 WB) render this approach impractical. Therefore, cultural and biological tactics must be used for short- and long-term ELHB management.

Pheromone Study of Acarid Mites XVII. : Identification of 2-Hydroxy-6-Methyl Benzaldehyde as the Alarm Pheromone of the Acarid Mite Tyrophagus perniciosus (Acarina:Acaridae), and Its Distribution among Related Mites

2-Hydroxy-6-methyl-benzaldehyde was identified as the alarm pheromone of the acarid mite, Tyrophagus pernicious, which is known as a pest attacking spinach culture and cucurbitaceous plants in the field and also in greenhouses. The compound, which was one of the major components of the hexane extract, was active at 10 ppm. Although this compound has been identified not only inmites, Acarus siro and Caloglyphus rodriguezi, but also int he common eucalypt longicorn Phoracantha semipunctata, this is the first report on its bilogical significance. Other than T. peniciosus, the compound is sporadically districuted among other species of the genus Tyrophagus, namely, four strains of T. putrescentiae among the five investigated and one of two strains of T. neiswanderi. It was not detected in T. similis.

European Hornet Damage to Ash and Birch Trees

SCRIVEN.G.T., EL. REEVES and R.F. LUCK.1986. Beetle from Australia threatens Eucalyptus. California Agriculture 40(7&8): 4-6. Since the eucalyptus longhorn borer was discovered in October 1984 infesting eucalyptus trees near El Toro, California, it has been spreading rapidly in the southern part of the state. Eucalyptus has been planted in California since the 1860s but has been free of major pests until the arrival of the borer, Phoracantha semipunctata, a cerambycid beetle. The borer is the first such pest to reach the United States from Australia, the native home of eucalyptus. One of the more common broadleaf trees in urban California, eucalyptus is potentially threatened by the beetle in landscape and woodlot plantings, especially when subjected to periodic moisture stress. Such stress, even for brief periods, increases vulnerability to attack. The beetle is a strong flyer and has been known to attack isolated trees nine miles from the nearest infested tree. Our preliminary observations suggest that eucalyptus species vary in susceptibility to attack under comparable drought conditions. Massive beetle attacks quickly kill Eucalyptus globulus and E. viminalis when their gum defenses decline. In contrast, the gum defenses of E. blakelyi continue to cause high mortality of larvae entering the bark. We are currently evaluating other species of Eucalyptus.

Seasonal development of the eucalypt borer,Phoracantha semipunctata, In Israel

Observations on the seasonal development ofPhoracantha semipunctata (Fab.) (Coleopteia: Cerambycidae), the eucalypt borer, were carried out in 11 plantations ofEucalyptus camaldulensis Dehn. and two ofE. gomphocephala DC, situated in areas from Qiryat Shemona (Upper Galilee) to Ze’elim (western Negev), using trap logs. Egg masses of the borer were usually found during the warm season but also in small numbers during the winter. Larvae which hatched during the colder season generally died, due to the relatively accelerated drying of the bark. Mean minimum duration of development from egg laying to the onset of adult emergence wasca 100 days for individuals which began to develop between spring and mid-summer (March to July);ca 215 days for the late summer brood (August to September); andca 195 days for the autumn brood (October to November). Mean larval development comprised about 66%, 64%, 36% and 81% of the total development period in spring, early and mid-summer, late summer, and autumn, respectively. Mean spring development of the larvae lasted 70 days in fresh materialvs 118 days in old (partly dry) material. The pupation period lasted between 32 and 40 days when it began between spring and late summer, andca 110 days when it started in the autumn. When adult emergence began between spring and mid-summer it was usually completed within 2–3 months, whereas when starting from late summer onward it lasted up to 9 months. Emergence was arrested during the winter and resumed with a rise of temperature in the spring. The borer develops two or three annual generations, depending upon the area.

Purification and some properties of two amylases from phoracantha semipunctata larvae

1. Two amylases were purified from Phoracantha semipunctata larvae (Coleoptera, Cerambycidae) in one step by affinity chromatography on cross-linked starch. 2. Both enzymes are activated by chloride ions. They differ in their optimum pH, pI and action pattern. 3. Amylase I can be classified as an exoamylase which splits amylose in maltotetraose units from the end of the polysaccharide chain. Amylase II behaves as a typical endoamylase (α-amylase).

Natural control of the eucalyptus borer, Phoracantha semipunctata (F.) (Coleoptera: Cerambycidae), by the Syrian woodpecker

AbstractScreened and unscreened eucalyptus trap-logs infested by Phoracantha semipunctata (F.) were used to examine the excavating habits of the Syrian woodpecker (Picoides syriacus), its annual course of predation and its effect on the survival rate of Phoracantha semipunctata larvae in Israel. The bird excavated predation holes only in trap-logs with larvae within the bark. Predation holes density increased during the spring and summer. Towards the autumn, egg-masses were killed too. The average mortality due to predation was 29·21% of total larval mortality and 78·7% among larvae that survived intraspecific competition. The mortality caused by the woodpecker decreased with increasing density of larvae. The natural control of P. semipunctata in Israel and the borer-woodpecker ecosystem are discussed.

Studies on the Digestion of Cellulose by the Larvae of the Eucalyptus Borer, Phoracantha semipunctata (Coleoptera: Cerambycidae)

Larvae of the native Australian xylophagous insect P. semipunctata, the adults of which lay eggs only on Eucalyptus species, penetrate the bark, then the phloem and feed at the boundary between the phloem and the xylem, causing deep furrows. As the phloem dries, they penetrate the xylem, which they damage by the formation of galleries. Digestion of wood is facilitated by glycosidases acting not only on oligosaccharides but also on many polysaccharides, notably starch, various hemicelluloses and cellulose. The role of a cellulase produced by the midgut epithelium of the larvae was examined and the characteristics of a partially purified preparation of this enzyme from the midgut epithelium studied. The enzyme was shown to have a molecular weight of less than 34500 and to hydrolyse carboxymethylcellulose and Cellulose-Azure: It was identified as being an endo-ft-l,4-glucanase.

Glycosidases and B group vitamins produced by six yeast strains from the digestive tract of Phoracantha semipunctata larvae and their role in the insect development

Six strains of yeasts were isolated from P. semipunctata larval gut in order to determine their role in insects nutrition. P. semipunctata larvae possess a rich glycosidasic equipment acting on oligosaccharides, heterosides and polysaccharides which is particularly characterized by an activity on hemicellulose. The yeast strains hydrolyze oligosaccharides, heterosides and some polysaccharides, such as starch and pectin, but no activity was detected on cellulose. β-Glucosidase was secreted in the medium by all strains except one. B group vitamins were also secreted by the yeasts.

Phoracantha semipunctata F.

EPPO BulletinVolume 13, Issue 1 p. 1O-4O Phoracantha semipunctata F. Coleoptera: Cerambycidae First published: January 1983 https://doi.org/10.1111/j.1365-2338.1983.tb01727.xAboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinked InRedditWechat Volume13, Issue1January 1983Pages 1O-4O RelatedInformation

Age-specific life-table data for the Eucalyptus boring beetle, Phoracantha semipunctata (F.) (Coleoptera: Cerambycidae), in Malawi

AbstractAge-specific life-table data were collected over a year for field and insectary populations of Phoracantha semipunctata (F.) on logs of Eucalyptus grandis in Malawi. Most mortality occurred in the larval stage, and the major mortality factor was intraspecific competition. Severe overcrowding led to a reduction in population density from one generation to the next. Overcrowding also led to a reduction in beetle size and to a shift in the sex ratio in favour of males. Elimination of potential breeding sites is recommended as an effective control measure for this pest.

Purification by chromatography and properties of a β-glucosidase from the larvae of Phoracantha semipunctata

1. 1. A β-glucosidase (β- d-glucosido glucohydrolase, EC 3.2.1.21) was purified from xylophageous larvae of the Cerambycidae, Phoracantha semipunctata, by ammonium sulfate precipitation, hydroxylapatite and DEAE-cellulose chromatography. 2. 2. On an acrylamide gel, the enzyme appeared as a single peak of protein. Molecular weight was approx. 100,000. 3. 3. The pH optimum was between 5 and 5.5 and the K m value 2.2 mM for p- nitrophenyl-β- d-glucopyranoside . 4. 4. The thermal stability of the enzyme and the effect of various cations and monosaccharides on activity were examined. 5. 5. The enzyme hydrolyzes various alkyl and aryl-β- d-glucosides, also cellobiose, but neither carboxymethyl cellulose nor cellulose. 6. 6. The main physiological rôle of the enzyme presumably consists in hydrolyzing the cellobiose liberated from the ingested wood by the degradation of the cellulose by the cellulasic complex in the midgut of the Phoracantha semipunctata larvae.

Colonisation of twelve species of Eucalyptus by Phoracantha semipunctata (F.) (Coleoptera: Cerambycidae) in Malawi

AbstractFelled logs of twelve species of Eucalyptus were exposed simultaneously to attack by Phoracantha semipunctata (F.) in Malawi. Colonisation was assessed by counting the number of larval feeding channels on the surface of the sapwood. The level of colonisation varied significantly between different tree species. E. fastigata and E. paniculata were much more heavily colonised than any of the other species. Possible factors contributing to this variation in susceptibility are discussed. The more susceptible species should be the most efficient for control operations involving the use of trap trees.