Effect of a foliar-applied biostimulant mixture on winter wheat (Triticum aestivum) under drought stress conditions

Abstract

Drought is one of the most common problems that can induce stress on crop production. Due to the rising temperatures caused by climate change, drought has become more frequent in many areas. It is crucial for the agricultural sector to look for more solutions on how to protect and increase plant productivity while using fewer chemical fertilisers. Studies show that biostimulants can act as anti-stress solutions, helping plants to mitigate drought stress while being an environmentally friendly option. The aim of this study was to evaluate the effect of different biostimulants on the morphological, physiological and biochemical parameters of winter wheat (Triticum aestivum L.) during stress and recovery periods. In this study, the biostimulants Terra-Sorb, Millerplex, and their mixture were used. Parameters were measured on the last day of the stress period and the last day of the recovery period. The results showed that drought significantly reduced the morphological parameters of winter wheat. Fresh biomass during drought decreased by approximately 39–53% compared with control (p < 0.05). Winter wheat sprayed with the mixture of biostimulants showed the smallest losses, with fresh biomass reduced by 38.85% and the net photosynthetic rate by 75.72% compared with control, indicating the highest tolerance to drought among all treatments. The mixture also maintained higher transpiration than the other treatments. During plant recovery period, biostimulants did not improve plant performance, and the biochemical parameters were not affected (p > 0.05). This study showed the effect of drought on morphological, physiological and biochemical parameters of winter wheat as well as the efficiency of different biostimulants during drought stress period, especially when biostimulants with two different active components were are used in combination.