Effects of environmental stress on seed characteristics of wild oat (Avena fatua): implications for seed bank dynamics

Kristen Granger

October 29, 2008 @ 01:20 pm to 02:15 pm

10 Tyson

Seed persistence in the soil allows many weedy and invasive plant species to disperse their seeds through time and space, and is a particular management issue for farmers. Dormancy, resistance to aging and protection against microbial decay are three traits that are thought to contribute to seed persistence. These characteristics may be linked by the phenolic compounds in the seeds, acting as germination inhibitors and antioxidants. It is hypothesized that environmental stresses during seed maturation reduce the allocation of phenolic compounds to the seeds and diminish seed persistence. Wild oat (Avena fatua) plants were grown under shade and drought, and the seeds were evaluated for phenolic content, dormancy, resistance to microbial decay, and seedling vigor. Preliminary data indicate that seeds from plants exposed to stressful conditions are less dormant, less resistant to decay, and less vigorous than seeds from non-stressed plants. These data may allow farmers to more accurately predict weed emergence and pressure, leading to more effective management strategies.