Abstract:
Abstract: A long-term, sustainable solution to weed infestation is extremely desirable because weeds
have the potential to reduce crop productivity and the aesthetic appeal of the environment. In this
study, the impacts of mowing and varying degrees of trampling pressure on the suppression of
weeds, alongside wound-induced changes in the allelopathic potential, of the rhizosphere soil and
the root exudates of southern crabgrass (Digitaria ciliaris) and Asian flatsedge (Cyperus microiria)
were evaluated under both field and greenhouse conditions. The field study results showed that
all trampling treatments induced the relative suppression of weed growth. Grass weeds showed
higher resistance to trampling than broad-leaved weeds. However, laboratory bioassays showed that
light trampling caused a significant increase in the growth-inhibitory effects of southern crabgrass
rhizosphere soil on lettuce. Moreover, mowing (9.11% of control) and trampling (16.4% of control)
resulted in a marginal increase in the growth-inhibitory effects of root exudates released from southern
crabgrass. Furthermore, the growth-inhibitory activities of the Asian flatsedge rhizosphere soil were
significantly reduced after heavy trampling pressure. Moreover, mowing and trampling resulted in
marginal reductions in the growth-inhibitory activities of root exudates released from Asian flatsedge
against lettuce (i.e., 18.7% and 28.5%, respectively). In general, mowing and varying degrees of
trampling induced contrasting and integrated impacts on weed suppression as well as the allelopathic
potential of both southern crabgrass and Asian flatsedge.
