Estimation of Evapotranspiration and Water Requirements of Strawberry Plants in Greenhouses Using Environmental Data

Farmers routinely determine irrigation requirements from visual observations and cultivation experience, but this can lead to under- or over-irrigation. To establish precise irrigation technology for strawberry cultivation, the average daily evapotranspiration and water requirements were estimated according to the amount of solar radiation. Environmental data was collected; air temperature and humidity from the center of the greenhouses and solar radiation from outside greenhouses. Makkink FAO24 equations (temperature and cloudiness) were used to estimate the evapotranspiration and water requirements. The temperature method showed higher correlation coefficients in solar radiation (R2 = 0.60), evapotranspiration (R2 = 0.76), and water requirements (R2 = 0.69) than other tested methods. The daily irrigation, calculated from the estimated evapotranspiration, was 3.8 tons/10a. It is possible to develop a precision irrigation system from estimated evapotranspiration during the cultivation of strawberries.