Within-season variability in mycorrhizal benefit to reproduction in Abutilon theophrasti Medic.

Mycorrhizal infection of Abutilon theophrasti Medic, increased seed quality and resultant offspring performance, but the improvement varied significantly with the timing of seed production. In general, offspring from mycorrhizal plants were superior to offspring from non-mycorrhizal plants, but the difference was greatest for the early cohort of seeds. Because increased seed size and quality can affect subsequent offspring competitive ability, increased variability in seed size and quality due to mycorrhizal infection may have an important impact on population dynamics of A. theophrasti.