Possibilities of Killing Weeds by Microwave Power

Weeds are the main problems for organic and traditional cropping system. According tothe researches, it was found that weeds decrease the yield by 21-61% especially in cotton andcorn production. Herbicides use for controlling weeds destroys the environment and increases thecost. Recently microwave applications are considered for controlling weed plants due to thegrowing concerns about herbicide resistance and chemical residues in the environment. Recentstudies proved that microwave can kill the weeds effectively.In this study, the possibilities of using microwave energy to kill the weeds between the rows wereinvestigated in corn and cotton production at laboratory conditions. Four weed varieties cocklebur(Xanthium strumarium), Johnson Grass (Sorghum halepense (L.)), Black Nightshade (Solanumnigrum), Bermuda Grass (Cynodon dactylon) were selected since they are the most common weedsfound at corn and cotton production. In the experiment, weeds with three different developmentstages: weeds with four leaves, eight leaves and weeds at seeding stage were exposed tominimum 0.8 kW and maximum 5.6 kW microwave power with four different forward speeds were0.05 –0.1 – 0.3 - 1 m s-1.According to the results; all four types of weeds were be able to be killed by microwaveapplications. The required microwave power to kill the weeds increased with increasing forwardspeed. It was found that forward speed of 1 m s-1 was not effective to kill the weeds withmaximum power of 5.6 kW. All four weeds required more power for killing when they are at lategrowing stages. Generally, cocklebur and Black Nightshade required less power comparing JohnsonGrass and Bermuda Grass. Bermuda Grass was the only weed which required maximum 5.6 kWmicrowave power level at all forward speeds at laboratory conditions.

Anahtar Kelimeler:

Microwave power

Possibilities of Killing Weeds by Microwave Power

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