Plant age, seasonality, and plant communication in sagebrush

摘要

Plants progress through a series of distinct stages during development and plant developmental phases link with changing seasons through a year. Recent work indicated that many plants activate systemic-induced resistance after herbivore attack, although the role of both plant ontogeny and seasonal variation in resistance against herbivores has not been a focus of this work. We previously reported that sagebrush become more resistant to its herbivores when neighboring sagebrush plants were experimentally clipped. In this study we asked how the age of sagebrush affected systemic-induced resistance and whether there was seasonal variation in systemic resistance. Young plants showed strong evidence of systemic-induced resistance only if airflow was permitted among branches. Moreover, volatile communication between individuals was stronger in young plants. We also found that plants with neighbors clipped in May accumulated less damage throughout the season relative to plants with neighbors that were clipped later in the summer.