Screening spruce for white pine weevil resistance
- Project description
- Distribution of P. strobi in North America
- Genetic variation in canadian weevil populations
- Range of Sitka spruce
- Sources tested for resistance in Western North America
- White pine weevil resistance screening trials
- Mass screening for resistance (Jordan River plantation)
- Ghost trial: studies using caged insects clarified the mating system of weevils
- Artificial wounding studies: Studying plant defenses
- Insect - plant relationships
- Are weevil resistant trees also resistant to other insects?
- Conclusions
- Selected references
Insect - plant relationships
| Plant Defenses | Effect on Insect | Insect Adaptation | ||
|---|---|---|---|---|
| Nutritional | <--> | Poor nutrition | <--> | Avoid, Compensate |
| Constitutive | <--> | Repellent Physical Toxic | <--> | Avoid Detoxify |
| Inducible | <--> | Repellent Toxic | <--> | Avoid, Suppress Detoxify |
| Guild | <--> | Confusion | <--> | Use alternate cues |
| ^------- | Adaptation | -------^ | ||
Adapted from Panda and Kush, 1995
Resistance mechanisms
The causes of resistance are currently being studied. After examining over 29,000 trees, it was concluded that resistance in spruce to the White pine weevil is likely to follow the model developed by Panda and Kush (1995). In this model resistance is viewed as a multi-layered defense system involving nutritional, constitutive, inducible and guild (or population) defenses. Some of these defenses may interfere with the physiology of the insect. These defenses are countered by weevil adaptations to avoid, suppress or detoxify these defenses.
Project status
- On-going