Boron foliar supplementation as a strategy to attenuate drought stress in soybean

Abstract

Drought is the major abiotic stress that limits growth, development and yield of crops worldwide. In this scenario, mineral nutrients, such as boron (B), have been promising for increasing the tolerance of plants to abiotic stresses because of their physiological roles in plants. We aimed to evaluate the benefits of foliar supplementation of B in either relieving or reducing the physiological damages caused by water stress in soybean (Glycine max L.). A greenhouse trial was carried out in a 2 × 3 factorial scheme, with two water conditions (well‐watered and drought stress) and three doses of B (0, 150 and 300 mg B L−1). Foliar application of B was before inducing the water stress, which remained for 20 days during vegetative stage. Plants were evaluated at three moments, according to the water conditions: maximum stress, rehydration and just before harvesting. The levels of hydrogen peroxide and lipid peroxidation increased in soybean leaves and roots under water stress, resulting in impaired plant growth. However, the foliar supplementation with B before the stress increased activities of the antioxidant enzymes and reduced the levels of stress markers. Furthermore, B applied foliar increased the nutrient concentration in the leaves of plants and stimulated root growth, which resulted in higher harvest index related to yield. The foliar application of B has shown as an alternative management to mitigate the damages caused by drought stress in soybean.

Boron Impact on Maize Growth and Yield: A Review

“…Additionally, foliar supplementation with B has been found to increase the activities of antioxidant enzymes, reduce stress markers, and stimulate root growth, resulting in a higher harvest index and yield [11]. Furthermore, foliar application of B can affect carbon fixation, metabolism, and allocation belowground, as well as improve plant uptake of other essential nutrients such as zinc [12]. Overall, foliar application of B provides an effective method for supplying this essential nutrient to maize plants, leading to improved growth, yield, and stress tolerance.…”