The purpose of this study was to investigate the effects of biostimulants on increasing the adaptive mechanisms of pea (Pisum sativum L.) under water deficit conditions, with an emphasis on optimising physiological functions, biochemical processes, and morphological development of plants. The experiment was conducted under controlled conditions that helped to accurately model the effect of water stress. The study used comprehensive evaluation methods, including physiological parameters (photosynthetic activity, transpiration), biochemical markers (antioxidant enzyme activity, proline level), and morphological parameters (length and weight of the root system). The findings confirmed that treatment with biostimulants significantly increased the adaptive potential of plants. Photosynthetic activity in the treated plants was 82%, which was substantially higher than in the control group, where this level reached only 60%. Transpiration in the treated plants stayed stable, ensuring optimised water balance even under stress. Biochemical analysis showed that the activity of superoxide dismutase and catalase in plants treated with biostimulants increased by 145% compared to control plants, which contributed to a major reduction in oxidative stress. The level of proline, as a key osmotic regulator, was also significantly higher in the treated plants, which maintained the stability of the cellular water balance. Morphological studies revealed that the plants treated with biostimulants had a more developed root system: the length of the roots was 10 cm longer, while the weight was greater than in the control. This helped the plants to use moisture from deeper soil layers, which improved their resistance to drought. As a result, the yield loss in the treated plants was half that of the control group. These findings highlighted the effectiveness of using biostimulants to increase pea resistance to water deficit and maintain productivity. This makes the proposed approach promising for implementation in agricultural technology, especially in arid regions where water deficit is the primary limiting factor for crops
Nebaba et al. (Tue,) studied this question.