Potential of superabsorbent hydrogels to improve agriculture under abiotic stresses

Hydrogels are a promising management option to increase the efficiency of water use in agriculture in arid and semi-arid regions. However, abiotic factors may affect hydrogel efficacy. The effect of abiotic stress on the swelling and residual acrylamide in hydrogels was evaluated. The treatments were three hydrogels (A, B and C), four temperatures (20, 30, 40 and 65 degrees C) and two salinities (0.003 and 3.0 dS m(-1)). The swelling degree and the residual acrylamide concentration of the hydrogels were measured. Data were analyzed with univariate and multivariate statistics. The swelling order of hydrogels under low salinity was A>C>B; at high salinity was B>A>C. All hydrogels presented swelling reduction at high salinity, with swelling reductions in A and C of 97% and 85%, respectively, while B presented a swelling reduction of 37% at 20 degrees C and greater than 89% at higher temperatures. Hydrogel B achieved good swelling under saline conditions, but only at 20 degrees C. Thus, the temperature tolerance of this hydrogel should be improved so it can be used to improve water use efficiency in regions with high temperatures and salinity levels. Residual acrylamide levels of hydrogels decreased by 95% over 30 days, being safe for agricultural applications.

Automated summary

The study investigated the impact of abiotic stress on the swelling and residual acrylamide in hydrogels, revealing that temperature and salinity can affect the swelling performance of hydrogels, with hydrogel B performing well under low temperature and high salinity conditions. The residual acrylamide levels in the hydrogels decreased significantly within 30 days.