APPLIED ECOLOGY AND ENVIRONMENTAL RESEARCH, vol.22, no.4, pp.3677-3690, 2024 (SCI-Expanded)
This
study investigates the depressive effects of diode laser radiation on commonly
found weed species in the Northwest Anatolian conditions. Unlike previous
laboratory-based experiments, this pilot study conducted in natural
environments aims to understand weed reactions to laser application under field
conditions. Cleavers (Galium aparine), small scabious (Scabiosa
columbaria), and sun spurge (Euphorbia helioscopia) were selected
for observation. A diode laser (5500 mW power, 450 nm wavelength) was applied
to plant apical meristems and stems at four doses for each species. Regression
analyses using dry-based remaining biomass and laser doses were performed with
the logistic growth model. The ED90 values, indicating a 90%
reduction in plant growth on the stem, were determined as 14.42 J for cleavers,
11.04 J for scabious, and 18.04 J for sun spurge. For apical meristem
applications, plant growth reduction was less than 90% at maximum energy doses,
with rates of 72.18% for cleavers and 41.64% for scabious. These results
support the thesis that laser application to the apical meristem region of the
weed may not be sufficiently effective beyond the cotyledon period. However,
the study concludes that laser application to the plant stem can successfully
control all three weed species.