Hilary L. Barker, Liza M. Holeski and Richard L. Lindroth
All living things are the product of their nature (genetics), nurture (environment) and the interaction between nature and nurture (genetics by environment interactions). In plants, these nature and nurture factors influence traits including growth and defense against insect pests. The relative importance of nature and nurture in shaping these traits can reveal the resiliency of plants to environmental stress both now and in the future.
Plant traits that are shaped more by nature (genetics) have a higher capacity to respond and evolve to various pressures (e.g., insect pests) over time (multiple generations). In contrast, plant traits that are shaped more by nurture (environment) can have a higher capacity to tolerate stress (e.g., drought) within a short timeframe (within one generation). In this study, we compiled the results from previous work on aspen, cottonwoods, and willow to assess how nature and nurture influence plant traits, including growth, defense, and interactions with insect pests.
We found that growth is shaped most strongly by the plant’s environmental context (e.g., availability of water and nutrients), whereas how well a plant can defend itself from insect pests (which is measured by levels of defense chemicals within the leaves) was primarily controlled by genetics. In addition, how well an insect pest can thrive on these plants is also shaped by the genetics of the plant. Thus, aspen, cottonwoods, and willow appear to have a high capacity to change their levels of defense in response to insect pests with time.
Aspen, cottonwoods and willows are pivotally important species in early-successional ecosystems throughout the northern hemisphere, and are also important species for commercial plantation production. Results from our work will improve understanding of the interplay of nature vs nurture in shaping the productivity and sustainability of these species in natural and managed settings, both now and in environments of the future.