Combining Excel Macros and Time Series to characterize the electrical signal of strawberry plants

The strawberry plant (Fragaria x ananassa Duchesne) is an important crop in Mexico, representing 7.8% of its production. Therefore, constant efforts are being made to increase its production and improve production techniques. One way to identify whether a plant's growing conditions are optimal is through measuring the electrical signal that it produces. Furthermore, a plant's electrical signal can be measured and quantitatively related to the intensity of the stimulating source, such as solar radiation or soil water content. Therefore, in this work, we propose to characterize the electrical signal of the strawberry plant. To perform the measurements, an Arduino data acquisition board was implemented as the measurement system. The experimental methodology consisted of placing an electrode on a leaf near the stem, at a distance of approximately 1 cm. The second electrode was inserted into the stem. The distance between the electrode tips was 2 cm. The electrodes were inserted parallel to the leaf, at a slight angle of 30 degrees, and at a depth of approximately 0.2 cm. Several studies have recommended placing the electrodes closer to points of high physiological activity, suggesting a better response to the electrical signal. This was measured in millivolts. The Holt method and an ARIMA (1,1,0) model were then used to analyze the plant's electrical signal. Among the most notable results is the characterization of the electrical signal in strawberry plants under different physical conditions.