Yield and Photosynthetic Efficiency of Selected Legume Species in Response to Superabsorbent Rate

With climate change contributing to soil moisture deficits, effective methods for water re-tention and rational water management are being sought. One solution to provide water for crops during periods of dry weather is the use of superabsorbents (SAP). The aim of this study was to determine the response of selected legume species to various doses of superabsorbent. The two-year experiments were set up in a randomised block design, with 4 replicates. The test factor was the dose of hydrogel, also known as superabsorbent: 0-control treat-ment (SAP0), 20 kg·ha-1 (SAP20) and 30 kg·ha-1 (SAP30). In the first experiment, the test object was Vicia faba L. cultivar Granit, and in the second experiment, Pisum sativum L. cul-tivar Batuta (narrow-leaved). The results of our study demonstrated a significant effect of superabsorbent application on the yield of faba beans and peas, with SAP application at a dose of 20 kg ha-1 being the most beneficial. The SAP doses used did not differentiate the factors influencing seed yield in faba bean. However, in peas, an increase in pod number and seed number per plant was observed with the SAP30 dose compared to the SAP20 dose. Application of super-absorbent at a dose of 20 kg ha-1 significantly increased photosynthesis rate in faba bean, the Fv/Fm index in the tested species, and the PI index in peas compared to the control. However, the superabsorbent did not affect transpiration rate or the WUE coefficient in the tested legume species. Significantly higher yields in faba bean and pea and all tested plant structure parameters in pea were recorded in 2018 compared to 2017. The tested parame-ters of gas exchange and chlorophyll fluorescence were higher in pea in 2018 (except for transpiration intensity) and in faba bean in 2017.