Evapotranspiration and biophysical coefficients of large-fruited tomatoes grown in unheated greenhouses under drip irrigation

  • 1 Institute of Soil Science, Agro-Technology and Plant Protection “Nikola Pushkarov", Sofia, Bulgaria


To determine the overall and average evapotranspiration of tomatoes grown in unheated greenhouses, studies were conducted under soil and meteorological conditions in the area of the village of Chelopechene – Sofia with drip irrigation.
The total evapotranspiration, which reaches 537 mm during the vegetation period of the crop, is experimentally determined, and the established daily evapotranspiration values range from 1.50 to 5.5 mm with two minima – at the beginning and end of the growing season and one maximum in August. . For the purposes of practice and design, the daily values of the biophysical coefficients Z, R and Kp are also calculated, which depends on the biological characteristics of the crop and the meteorological factors.


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