Estimation of Water Requirement and Crop Coefficients of Two Salicornia Species in Yazd

Water and soil resources of the country are limited, and the optimal use of water resources in agriculture requires estimation of the exact amount of water consumption by different plants in different conditions. This study was conducted to investigate evapotranspiration, crop coefficient, and water requirements of salicornia under lysimetric conditions in a factorial experiment with completely randomized design. The experimental treatments were two species of salicornia (Salicornia bigelovii and Salicornia persica) and two levels of irrigation water salinities (8 and 25 dS.m-1) in three replications. The actual evapotranspiration (ETa), reference evapotranspiration (ET0), and crop coefficients (Kc) of salicornia species were determined at three main salicornia growth stages. The results showed that increase in irrigation water salinity from 8 to 25 dS.m-1caused significant changes in yield (biomass and seed yield) of the two salicornia species at the 1-percent probability level. Moreover, the amount of irrigation water consumption in different treatments and replications varied from 28 to 33 thousand cubic meters per hectare. For the salinity level of 8 dS.m-1, the Kc values at the beginning, middle, and end of growing season of bigelovii specie were obtained as 1.18, 1.55, and 1.42, respectively, while for the salinity level of 25 dS.m-1, these values were 1.06, 1.37, and 1.26, respectively. For persica specie, the Kc values of the beginning, middle, and end of the growing season were 1.37, 1.58, and 1.10 (for salinity level of 8 dS.m-1) and 1.15, 1.38 and 1.27 (for salinity level of 25 dS.m-1), respectively. In addition, water use efficiencies of salicornia varied from 0.21 to 0.38 kg.m-3 at different treatments and species.