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The effectiveness of Arduino microcontroller board in the assessment of the optimum
soil moisture status for irrigation needs of dry season tomato orchard in Akure (7° 15’ N, 5° 12’ E)
was investigated from November 2016 to February 2017. The experimental design was a randomized
complete block replicated three times with four treatments consisting of Arduino microcontroller
board, VG-Meter 200, Pascal soil moisture meter and the gravimetric soil moisture determination
method. The Arduino micro-controller board was coupled with Global System for Mobile
communications (GSM) base shield that was joined through cables, to hygrometer sensor. A computer
coded instruction to determine optimal soil moisture level was uploaded onto the Arduino board.
The Arduino hygrometer moisture sensor was inserted into the soil while the sensors of the VGMeter
200, Pascal soil moisture meter were inserted into the soil in the respective plots. The
gravimetric soil moisture determination method, entailed taking soil samples to the laboratory for
soil moisture determination. Tomato seeds UC82B variety were raised in the nursery and
transplanted at four weeks and the plots mulched with wood shavings. The total volume of water
added in gravimetric plot was 80 %, 80 % and 100 % higher than in VG-Meter 200, Pascal meter
and Arduino plots respectively even though the tomato yield value of 20.5 t/ha was obtained in
Arduino micro controller board plot and higher by 3 %, 9.6 % and 12.6 % over the yield obtained
in Pascal meter, VG Meter 200 and the gravimetric method respectively.
Keywords: Arduino micro-controller board, Plant available water, Irrigation needs, Tomato orchard