The effect of mycorrhizal infection of Abutilon theophrasti on competitiveness of offspring

1. Our goal was to determine whether mycorrhizal infection of one generation of plants could influence the competitiveness of the subsequent generation. 2. We grew the offspring of mycorrhizal (M) and non-mycorrhizal (NM) Abutilon theophrasti plants together in dense populations in large boxes in a greenhouse. 3. Offspring of M plants were larger than offspring of NM plants. As the experiment progressed, the difference in size was magnified and self-thinning occurred. 4. Compared with offspring of NM plants, offspring of M plants had a twofold greater survival and collectively produced a total of nearly four times as many seeds. 5. We conclude that mycorrhizal infection of the parent generation can increase the competitive ability of the offspring.