Lodgepole pines are ecologically and economically important. With climate change creating unsuitable conditions for pine trees and more suitable conditions for mountain pine beetle, the ability of pine tree defences to withstand insect attacks is even more critical for the survival of these trees. Our understanding of the defence strategies in pines is important for informing us of the possible limitations of these systems in a changing climate. Understanding the relationship between chemical defence production, morphological defence characteristics and growth will help to inform future research and forest management.
I expected there to be some relationships and some trade-offs between variables as plants face different abiotic and biotic stresses and have limited resources. I hypothesized that due to the growth-differentiation hypothesis in which plants face a trade-off between allocating resources to growth or to chemical or morphological changes, plants will invest similarly to chemical and morphological defences while investing fewer resources to growth. I found that total resin duct area and resin duct production were somewhat correlated with terpene concentrations. Non-structural carbohydrates were only slightly correlated to resin duct production and were somewhat correlated to relative resin duct area and resin duct density. Terpenes were highly correlated to radial growth and basal area increment. These results indicate that trees are able to allocate resources to both defence and to growth and more research is needed to determine if this relationship changes with time, especially as climate change contributes to a warmer and drier climate in these areas.
I expected there to be some relationships and some trade-offs between variables as plants face different abiotic and biotic stresses and have limited resources. I hypothesized that due to the growth-differentiation hypothesis in which plants face a trade-off between allocating resources to growth or to chemical or morphological changes, plants will invest similarly to chemical and morphological defences while investing fewer resources to growth. I found that total resin duct area and resin duct production were somewhat correlated with terpene concentrations. Non-structural carbohydrates were only slightly correlated to resin duct production and were somewhat correlated to relative resin duct area and resin duct density. Terpenes were highly correlated to radial growth and basal area increment. These results indicate that trees are able to allocate resources to both defence and to growth and more research is needed to determine if this relationship changes with time, especially as climate change contributes to a warmer and drier climate in these areas.