| 1. |
- Azeem, Muhammad, et al.
(författare)
-
Chemical composition and antifeedant activity of some aromatic plants against pine weevil (Hylobius abietis)
- 2020
-
Ingår i: Annals of Applied Biology. - : Blackwell Publishing Ltd. - 0003-4746 .- 1744-7348.
-
Tidskriftsartikel (refereegranskat)abstract
- The pine weevil Hylobius abietis is an important pest causing severe damage to conifer seedlings in reforestation areas in Europe and Asia. Plants that have no evolutionary history with the pine weevil are of special interest in the search for compounds with a strong antifeedant activity. Thus, the essential oils of nine aromatic plants, viz Amomum subulatum, Cinnamomum tamala, Curcuma longa, Laurus nobilis, Ocimum basilicum, Origanum majorana, Origanum vulgare, Syzygium aromaticum and Trachyspermum ammi were extracted by hydrodistillation. The essential oil constituents were identified by gas chromatography–mass spectrometry, and antifeedant properties towards the pine weevil were assessed using choice feeding bioassay. The essential oils of C. longa, O. majorana, S. aromaticum and T. ammi showed an excellent antifeedant activity towards the pine weevil for 24 hr, whereas the essential oil of other plants showed the activity for 6 hr. There was a positive correlation between the amount of benzenoid compounds and the antifeedant activity of the essential oils. This study suggests that pine weevil non-host plant compounds have potential to be used for the protection of seedlings against pine weevil feeding. However, further study will be needed to explore the antifeedant activity of individual components and oils in the laboratory as well as in the field.
|
|
| 2. |
- Nordlander, Göran, et al.
(författare)
-
Trap catch data are poor predictors of damage caused by pine weevil (Hylobius abietis) to conifer seedlings
- 2023
-
Ingår i: Forest Ecology and Management. - 0378-1127 .- 1872-7042. ; 537
-
Tidskriftsartikel (refereegranskat)abstract
- Damage to planted conifer seedlings caused by the pine weevil Hylobius abietis (L.) is a severe and persistent threat to successful forest regeneration in Europe. Various countermeasures are available, which vary in effectiveness, costs and environmental impact, but none are ideal for all situations. Therefore, there is strong interest in robust assessments of damage risks, as they would enable more cost-effective and environmentally friendly forest pest management. It has been suggested that numbers of adult pine weevils caught in host-odour baited traps placed in regeneration sites may be valuable in such risk assessments. However, published studies provide at most weak support for the hypothesis that trap catch data provide adequate predictions of damage. Therefore, we conducted a two-year field study, designed to determine the relationship between weevil trap catch and subsequent damage at 10 regeneration sites in central Sweden. Site factors that might influence pine weevil feeding on seedlings were recorded and used as explanatory variables in the analysis. Stoniness was the only site factor identified as having a significant effect; damage mainly increased with increases in stoniness. No significant correlation was detected between damage to planted conifer seedlings and numbers of pine weevils trapped in the same locations. We suggest that this lack of correlation between weevil numbers and damage is due to planted seedlings only constituting a minor part of the weevils food intake and considerable between-site variation in availability of food sources other than seedlings. Therefore, assessment of pine weevil numbers appears unlikely to be useful for predicting damage risk at specific regeneration sites.
|
|
