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...     

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.     

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.     

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.     

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     

Acaricidal activities of the active component of Lycopus lucidus oil and its derivatives against house dust and stored food mites (Arachnida: Acari)

BACKGROUND: Recent studies have focused on materials derived from plant extracts as mite control products against house dust and stored food mites because repeated use of synthetic acaricides had led to resistance and unwanted activities on non‐target organisms. The aim of this study was to evaluate the acaricidal activity of materials derived from Lycopus lucidus against Dermatophagoides farinae, D. pteronyssinus and Tyrophagus putrescentiae. RESULTS: The LD₅₀ values of L. lucidus oil were 2.19, 2.25 and 8.45 µg cm^?2 against D. farinae, D. pteronyssinus and T. putrescentiae. The acaricidal constituent of L. lucidus was isolated by chromatographic techniques and identified as 1‐octen‐3‐ol. In a fumigant method against D. farinae, the acaricidal activity of 1‐octen‐3‐ol (0.25 µg cm^?2) was more toxic than N,N‐diethyl‐m‐toluamide (DEET) (36.84 µg cm^?2), followed by 3,7‐dimethyl‐1‐octen‐3‐ol (0.29 µg cm^?2), 1‐octen‐3‐yl butyrate (2.32 µg cm^?2), 1‐octen‐3‐yl acetate (2.42 µg cm^?2), 3,7‐dimethyl‐1‐octene (9.34 µg cm^?2) and benzyl benzoate (10.02 µg cm^?2). In a filter paper bioassay against D. farinae, 1‐octen‐3‐ol (0.63 µg cm^?2) was more effective than DEET (20.64 µg cm^?2), followed by 3,7‐dimethyl‐1‐octen‐3‐ol (1.09 µg cm^?2). CONCLUSION: 1‐Octen‐3‐ol and 3,7‐dimethyl‐1‐octen‐3‐ol could be useful as natural agents for the management of three mite species. Copyright © 2011 Society of Chemical Industry     

Electrophysiological and behavioural responses of Pityophthorus pubescens (Coleoptera: Scolytinae) to (E,E)‐α‐farnesene, (R)‐(+)‐limonene and (S)‐(−)‐verbenone in Pinus radiata (Pinaceae) stands in northern Spain

BACKGROUND: Some twig beetles in the genus Pityophthorus (Coleoptera: Scolytinae) may vector pitch canker disease Fusarium circinatum (Niremberg & O'Donnell) of Pinus spp. (Pinaceae). Because Pityophthorus pubescens (Marsh.) has been found to be associated with F. circinatum in the Basque Country (northern Spain), various experiments were conducted to assess the beetle's behavioural responses to (E, E)‐α‐farnesene, (R)‐(+)‐limonene and (S)‐(?)‐verbenone to develop a potential inhibitor to host attraction. These experiments comprise electroantennographic and double‐choice olfactometer tests, as well as field assays in Pinus radiata D. Don stands. RESULTS: Both sexes of P. pubescens showed similar electroantennographic responses to different doses (from 1 ng to 1 µg in decadic steps) of each individual compound, with depolarisations to (S)‐(‐)‐verbenone (100 ng) being similar to those of the aggregation pheromone (+)‐trans‐pityol. In olfactometer assays, both sexes were significantly attracted to (+)‐trans‐pityol, but the attraction was reduced when increasing amounts of the chemicals were added to the pheromone. Particularly relevant was the repellent effect induced by (S)‐(?)‐verbenone at 1 ng dose and higher. In the field, (E, E)‐α‐farnesene, (R)‐(+)‐limonene and (S)‐(?)‐verbenone reduced significantly the number of beetles attracted to (+)‐trans‐pityol and racemic trans‐pityol, with (S)‐(?)‐verbenone being the most effective. CONCLUSIONS: (S)‐(?)‐Verbenone showed an interesting potential for use in the protection of P. radiata stands. A potentially effective strategy, which could be implemented in further, more in‐depth studies, could involve the use of this semiochemical as repellent and (+)‐trans‐pityol‐baited traps as attractant in a ‘push‐pull’ strategy. Copyright © 2012 Society of Chemical Industry     

Research activities focused on management of red palm weevil at the UJI‐IVIA Associated Unit (Region of Valencia,Spain)

During the past 5 years, the Associated Unit between Institut Valencià d’Investigacions Agràries (IVIA) and Universitat Jaume I (UJI) has been working on the management of Rhynchophorus ferrugineus. The host status of Washingtonia filifera, Chamaerops humilis and Phoenix theophrasti was established, and complete resistance via antibiosis was described for W. filifera. A thermal constant (egg to adult) of 989.3 degree‐days has been established for R. ferrugineus when feeding in live P. canariensis. Based on this result, less than one annual generation is expected in areas with mean annual temperature below 15°C, and more than two if above 19°C. Assays on chemical control showed that a dose of 1.14 g aluminium phosphide m^?3 for 3 days is enough to kill all stages of R. ferrugineus in infested palms. The efficacies of imidacloprid and a microencapsulated paint containing chlorpyrifos and pyriproxyfen were also studied. Imidacloprid had high efficacies when applied as a drench either as a preventive or a curative treatment, whereas the paint was effective as a preventive treatment only. Biological control by use of entomopathogenic nematodes and fungi has been explored. Steinernema carpocapsae resulted in high efficacies when applied in a chitosan formulation. Beauveria bassiana also gave very good results, and new assays are under way to improve its use.     

Feeding‐deterrent activity of α‐asarone isomers against some stored Coleoptera

All isomers of α‐asarone [(E)‐4‐prop‐1‐enyl‐1,2,5‐trimethoxybenzene] were tested for their feeding deterrent activity against adults of Sitophilus granarius and Tribolium confusum and larvae of Trogoderma granarium and Tribolium confusum. (E)‐2‐prop‐1‐enyl‐1,3,5‐trimethoxybenzene exhibited the strongest deterrent activity against all the species tested. The total coefficients of deterrency for this compound were 140.6 and 169.7 for Tribolium confusum adults and larvae, respectively, and 144.9 and 104.6 for larvae of Trogoderma granarium and adults of Sitophilus granarius, respectively. © 2000 Society of Chemical Industry