Maternal Warming Modulates the Recruitment Biology of an Invasive Lettuce

Offspring performance is affected by maternal environment. Seedling establishment is one of the most vulnerable stages of life history and recruitment in annual plants. The purpose of this study was to investigate the effect of maternal warming on seed characteristics and early plant growth of a widespread annual weed, prickly lettuce (Lactuca serriola L.). A field experiment was conducted using open top chambers to passively increase temperatures in this study. The results suggest that maturation temperature can accelerate the life cycle of this species via seedling recruitment and early development of it. Seeds from warmed environment showed less dormancy than seeds from the ambient environment. Emergence time was significantly shortened by maternal warming. Furthermore, maternal warming increased significantly the number of true leaves and seedling mass in 4-week-old plants. Positive reproductive responses of the maternal generation and the effects of maternal warming on seedling performance may exacerbate invasions of this species under climate change. This may cause rapid population growth and more seed production in consistently warmer climates

Keywords:

Lactuca serriola , maternal environmental effect , climate change , germination , recruitment