Paper Title
Determination of Possibilities of Microwave Application For Killing Weeds
Abstract
Weeds are the main problems for organic and traditional cropping system. According to the researches, it was
found that weeds decrease the yield by 21-61% especially in cotton and corn production. Herbicides use for controlling
weeds destroys the environment and increases the cost. Recently microwave applications are considered for controlling weed
plants due to the growing concerns about herbicide resistance and chemical residues in the environment. Recent studies
proved that microwave can kill the weeds effectively. Unfortunately, microwave application is still quite expensive
comparing traditional weed control systems. The objectives of this study were to determine the possibilities of using
microwave energy to kill the weeds between the rows and find out the limit power levels for killing the weeds which
becomes a great problem in corn and cotton production. This study was conducted at laboratory conditions in order to
determine microwave energy levels at which four weed varieties cocklebur (Xanthium strumarium), Johnson Grass
(Sorghum halepense (L.)), Black Nightshade (Solanum nigrum), Bermuda Grass (Cynodon dactylon) die out according to
weed density and forward speeds of the laboratory prototype. Weeds with three different development stages: weeds with
four leaves, eight leaves and weeds at seeding stage were exposed to minimum 0,8 kW and maximum 5,6 kW microwave
power with two different forward speeds were 0,3 – 0,1 m s
-1
. According to the results; all four types of weeds were be able
to be killed by microwave applications. The required microwave power to kill the weeds increased with increasing forward
speed. The weeds were not affected by microwave power at forward speed of 1 m s
-1
. The microwave power levels for
killing the weeds at 0,075 m s
-1
forward speeds were measured as 0,8 kW, 2,4 kW, 0,8 kW and 4,8 kW for cocklebur,
Johnson Grass, Black Nightshade and Bermuda Grass respectively. Generally, cocklebur and Black Nightshade required
much less power comparing Johnson Grass and Bermuda Grass. Bermuda Grass was the only weed which required
maximum 5,6 kW microwave power level at all forward speeds at laboratory conditions.
Keywords- Microwave power, weed management