Laboratory and field evaluation of the pathogenicity of entomopathogenic nematodes to the red palm weevil, Rhynchophorus ferrugineus (Oliv.) (Col.: Curculionidae)

Ten Egyptian and imported entomopathogenic nematodes were evaluated for their pathogenicity to R. ferrugineus in both the laboratory and the field. In the laboratory, most nematodes were pathogenic to the pest larvae, pupae and adults. Larvae and adults were more susceptible to nematode infection (mostly 100% mortality) than pupae enclosed in their cocoons. In the field however, the highest insect larval mortality was 66.67% and most of nematodes failed in controlling the pest. Such failure could be due to hot weather, the tunnelling behaviour of the pest larvae and the too much sap in the infested sites in the trunks of palm trees.     

Development of the red palm weevil, Rhynchophorus ferrugineus (Olivier), (Coleoptera, Curculionidae) on natural and synthetic diets

The development of the red palm weevil, Rhynchophorus ferrugineus (Olivier) was investigated on a newly developed semiartificial diet as compared with two natural diets namely sugarcane stem and banana fruit. The weevil was successfully maintained on these diets and duration of the life cycle for males and females, respectively were 164.97 and 194.61 days on the semiartificial diet, 192.5 and 186.5 days on banana, and 172.00 and 170.00 days on sugarcane. The average egg production per female was shown to be significantly higher on the semiartificial diet, being 184.00±18.68 eggs compared with an average of 125.00±11.97 and 133.00±15.21 eggs on banana and sugarcane, respectively. The fertility ranged between 94–100% in those eggs deposited by females previously reared on the tested diets. The developed semiartificial diet was shown to be suitable for maintaining laboratory colonies of the red palm weevil, and it can substitute natural diets.     

Development of the red palm weevil, Rhynchophorus ferrugineus (Olivier), (Coleoptera, Curculionidae) on natural and synthetic diets

The development of the red palm weevil, Rhynchophorus ferrugineus (Olivier) was investigated on a newly developed semiartificial diet as compared with two natural diets namely sugarcane stem and banana fruit. The weevil was successfully maintained on these diets and duration of the life cycle for males and females, respectively were 164.97 and 194.61 days on the semiartificial diet, 192.5 and 186.5 days on banana, and 172.00 and 170.00 days on sugarcane. The average egg production per female was shown to be significantly higher on the semiartificial diet, being 184.00±18.68 eggs compared with an average of 125.00±11.97 and 133.00±15.21 eggs on banana and sugarcane, respectively. The fertility ranged between 94–100% in those eggs deposited by females previously reared on the tested diets. The developed semiartificial diet was shown to be suitable for maintaining laboratory colonies of the red palm weevil, and it can substitute natural diets.     

入侵害虫红棕象甲转移为害本土棕榈树的风险评估

为评估入侵害虫红棕象甲Rhynchophorus ferrugineus对本土农林生态系统的风险,于2016—2019年采用受害植株调查和成虫诱捕的方法跟踪监测该虫在加拿利海枣Phoenix canariensis引种点及周边1 600 m半径范围内本土棕榈Trachycarpus fortune上的发生情况,并对来自野外加拿利海枣与棕榈上的成虫形态及繁殖力进行比较。结果显示,红棕象甲可随加拿利海枣引种定植而入侵当地生态系统,当其在加拿利海枣上暴发成灾后,还能转移到周边棕榈上继续为害,红棕象甲为害致死的棕榈植株数随着引种植物死亡数的增加而增加。野外加拿利海枣与棕榈上红棕象甲成虫的体重、体长以及按雌雄1∶1配对交配后的产卵量、孵化率相当,但棕榈种群雌虫的翅展较加拿利海枣种群明显变短,表明红棕象甲转移取食本土棕榈后可成功定殖、建立种群,且适合度并未降低。雌虫翅展变短可能与该入侵种表型可塑性有关,反映出其对棕榈的快速适应与进化,表现为"前适应"策略。考虑红棕象甲成虫飞行能力强,建议调高棕榈分布省份该虫的风险预警等级、调整防控策略,开展跟踪监测以了解入侵地实情。     

The thermal constant for timing the emergence of the Red Palm Weevil, Rhynchophorus ferrugineus (Oliv.) (Coleoptera, Curculionidae)

The pupal duration of the red palm weevil, Rhynchophorus ferrugineus (Oliv.) at two different temperatures revealed that the thermal threshold is –2.3°C, while the thermal constant is 423 degree days. Around 20.7 cycles of weevil emergence per year have been predicted in Egypt. A temperature between 44–45°C was found to be the higher threshold at which the pupae are killed. The heat units required for the pupal development were utilized to predict the dates of adult emergence throughout the year.     

Pests of the palm (Palmae sp.) and date palm (Phoenix dactylifera) determined in Turkey and evaluation of red palm weevil (Rhynchophorus ferrugineus Olivier) (Coleoptera:Curculionidae)

This paper covers the palm ( Palmae sp.) and date palm ( Phoenix dactylifera ) pests which were determined by studies conducted in Turkey between 1941 and 2006. In total 15 species have been found to date: 1 belonging to Coccidae, 9 to Diaspididae, 1 to Margarodidae and 2 to Pseudococcidae families of the order Homoptera and 1 species to Scarabaeidae and 1 to Curculionidae families of the order Coleoptera. Among these pests, red palm weevil ( Rhynchophorus ferrugineus Olivier) has caused a great deal of damage in recent years.     

Recommendations for a preventive strategy to control red palm weevil (Rhynchophorus ferrugineus,Olivier) based on the use of insecticides and entomopathogenic nematodes

The red palm weevil, Rhynchophorus ferrugineus (Olivier) (Coleoptera, Curculionidae), has been present in Andalusia since 1993 although its major expansion began in 2005. Currently, the implementation of an action protocol against the red palm weevil based on curative and preventive treatments has a high cost. The aim of this work is to establish a minimum frequency between preventive treatments that would reduce costs. Three frequencies of application were evaluated (at 45, 60 and 90 days).The results show that preventive treatments can decrease the reproductive potential of the pest, but do not prevent the infestation of palm trees. Preventive treatments every 60 days effectively reduce costs and increase the survival of the palm trees.     

Optimizing components of pheromone-baited trap for the management of red palm weevil,Rhynchophorus ferrugineus (Coleoptera: Curculionidae) in date palm agro-ecosystem

Journal of Plant Diseases and Protection - The red palm weevil (RPW), Rhynchophorus ferrugineus (Olivier), is managed in date palm groves, inter alia, with food-baited pheromone traps. Laboratory...     

Entomopathogenic fungi and nematodes against larvae of the chestnut weevil,Curculio elephas (Coleoptera: Curculionidae): a laboratory evaluation

Pest control in chestnut orchards is mainly achieved by chemicals, but there is growing focus on the potential use of biological control agents. The larval susceptibility of the chestnut weevil Curculio elephas L. (Coleoptera: Curculionidae) to different strains/species of entomopathogenic fungi and nematodes was evaluated in laboratory by soil cup bioassays. In the experiments with fungi, a wild strain of Metarhizium anisopliae caused the highest larval mortality (about 90%) compared with a commercial and a wild strain of Beauveria bassiana (80% and 77% respectively). Regarding nematodes, the commercial strain of Heterorhabditis bacteriophora was more effective in the control of chestnut larvae (77% insect mortality) than Steinernema carpocapsae (43%).     

LATEX paint as an antifeedant againstHylobius abietis (L.) (Col., Curculionidae) on conifer seedlings

LATEX paint in water solution applied to newly planted conifer seedlings was found to prevent damage byHylobius abietis adult weevils for the whole season. Treatment of the basal third of the trunk was sufficient. Also, utilisation of the results as a model for deerantifeedant treatments and protection againsts the weevils is recommended.With 1 figure     

Monitoring ofHylobius abietis (L.) (Col., Curculionidae) populations by two types of baited pitfall traps

Two types of baited pitfall traps with standardized food attractants (alpha-pinene, 96% ethanol and water) were compared in monitoringHylobius abietis (L.) populations at several localities in southern Bohemia (Czech Republic). The smaller type (volume 1 l)) proved less useful in comparison with the larger type (volume 15 l). The latter type is described and discussed in more detail with respect to its application in the field.Zwei Typen von Bodenfallen, beködert mit standardisiertem Fraßlockstoff (-Pinen; 96% Äthanol; Wasser) wurden zur Überwachung vonH. abietis an verschiedenen Standorten im südlichen Böhmen (C R) verglichen. Der kleinere Typ (Volumen 1 l) erwies sich als weniger gut geeignet als der größere Typ (Volumen 15 l). Letzterer wird ausführlich beschrieben und hinsichtlich seiner Anwendung im Freiland erörtert.

---

With 2 figures     

First report of Heterorhabditis bacteriophora (Poinar, 1975) (Nematoda: Heterorhabditidae) isolated from the red palm weevil, Rhynchophorus ferrugineus (Oliver, 1790) (Coleoptera: Curculionidae) in Turkey

Infestation levels of the red palm weevil, Rhynchophorus ferrugineus (Oliver, 1790) and its natural enemies on palm trees in recreation areas were investigated in the Adana province of Turkey in 2008. The trunks of dead palms were sampled for R. ferrugineus and for the presence of entomopathogenic nematodes. While 20% of Phoenix canariensis Hort. were found to be killed by R. ferrugineus , only 2 trees from other species, 1 Washingtonia filifera (L. Linden) and 1 Phoenix dactlylifera L., were killed. Only one species of entomopathogenic nematode, Heterorhabditis bacteriophora ( Poinar, 1975 ) (Nematoda: Heterorhabditidae), was isolated from the R. ferrugineus specimens. Seasonal mortality rate in the total larval population (total 565 larval specimens) of R. ferrugineus was 69%. H. bacteriophora resulted in a significant mortality rate (80%) in the pupae population (total 314 pupal specimens). Overall, 70% of the total of 879 pre-adult specimens were found to be fatally infested by the attacks of this nematode. Heterorhabditis bacteriophora killed few adults, corresponding to 2% of the overall mortality rate. It is concluded that H. bacteriophora could be evaluated as a potential candidate for biological control of R. ferrugineus in the Mediterranean region.     

防范外来危险性害虫褐纹甘蔗象入侵为害

褐纹甘蔗象Rhabdoscelus lineaticollis（Heller）是为害棕榈科植物和甘蔗的危险性外来害虫。为警惕该虫的传入,本文对褐纹甘蔗象的分类地位、形态特征、分布、寄主、危害、生物学特性等作了简要介绍,并提出了预防建议。     

Field efficacy of imidacloprid and Steinernema carpocapsae in a chitosan formulation against the red palm weevil Rhynchophorus ferrugineus (Coleoptera: Curculionidae) in Phoenix canariensis

BACKGROUND: The invasive red palm weevil, Rhynchophorus ferrugineus (Olivier), has become the major pest of palms in the Mediterranean Basin. Chemical control against this species is difficult because of its cryptic habits and is mainly based on the repeated application of large quantities of synthetic insecticides. The aim of this work has been to evaluate in the field the efficacy of imidacloprid (Confidor^® 240 OD) and Steinernema carpocapsae Weiser with chitosan (Biorend R^® Palmeras) as soil and stipe treatments respectively, alone or in combination, against this pest. RESULTS: All treatments significantly reduced the mean number of immature stages of R. ferrugineus per palm. However, there were no significant differences among the different treatments considered. Efficacies ranged from 83.8 to 99.7% for the mean number of immature stages found in the palms and resulted in a significant increase in palm survival compared with the untreated control (75.0–90.0% versus 16.5% respectively). CONCLUSION: Both imidacloprid and S. carpocapsae in a chitosan formulation proved highly effective against R. ferrugineus in the field, and their efficacies did not significantly change when used in combination. Copyright © 2009 Society of Chemical Industry     

Phenology, damage and parasitoids of the apple leaf cutter Coenorhinus pauxillus (Germ.) (Col.: Attelabidae)

An outbreak on apple permitted a closer look at Coenorhinus pauxillus (Germar) (Col.: Attelabidae). The adult weevils emerge from mid-March onwards and attack the first unfolding leaves. Infested leaves drop when the larvae are in the 1^st or 2^nd instar, and it takes a further 4 weeks before the larvae are ready to pupate. Rearing of field-collected eggs and larvae is described. Leaf decomposition is an essential condition for pupation, as the fully-grown larvae do not leave their mine actively. Part of the population pupates more or less immediately and produces adult weevils in autumn. However, up to 70% of the weevils remain in prolonged diapause; their pupation does not take place before the summer of the following year. Damage by the weevil involves not only the loss of leaves of flower clusters and shoots, but also feeding damage to young fruits. Two parasitoids were found. Observations indicate that 3–4 subsequently more abundant generations of Anaphes brachygaster Debauche (Hym.: Mymaridae) develop in eggs of C. pauxillus. Probles brevicornisHorstmann (Hym.: Ichneumonidae, Tersilochinae) emerges in May and oviposits in young weevil larvae on the tree. The parasitoid does not develop into a pupa until its host starts pupating. The outbreak of apple leaf cutter did not decline over three years, but did not spread into adjacent plantings.     

Infection of Tomicus piniperda (Col., Scolytidae) with Canningia tomici sp. n. (Microsporidia, Unikaryonidae)

Canningia tomici sp. n. (Microsporidia, Unikaryonidae) infects the midgut epithelium, the gut muscules, Malpighian tubules, connective tissues, adipose tissues and the gonads of the pine shoot beetle, Tomicus piniperda (L.) (Coleoptera, Scolytidae). The infection is present in populations of Tomicus piniperda in Europe and in the United States. Uninucleate oval single spores occur in two sizes: 2.8±0.4× 1.4±0.4m and 3.8±0.3×2.0±0.2m. The polar filament of this microsporidium is fixed subapically in a flat anchoring disc. The thick posterior lamellae of the binary polaroplast are asymmetric due to the lateral fixation of the polar filament.     

Infection of Tomicus piniperda (Col., Scolytidae) with Canningia tomici sp. n. (Microsporidia, Unikaryonidae)

Canningia tomici sp. n. (Microsporidia, Unikaryonidae) infects the midgut epithelium, the gut muscules, Malpighian tubules, connective tissues, adipose tissues and the gonads of the pine shoot beetle, Tomicus piniperda (L.) (Coleoptera, Scolytidae). The infection is present in populations of Tomicus piniperda in Europe and in the United States. Uninucleate oval single spores occur in two sizes: 2.8±0.4× 1.4±0.4m and 3.8±0.3×2.0±0.2m. The polar filament of this microsporidium is fixed subapically in a flat anchoring disc. The thick posterior lamellae of the binary polaroplast are asymmetric due to the lateral fixation of the polar filament.