Application of Trehalose and Salicylic Acid Mitigates Drought Stress in Sweet Basil and Improves Plant Growth

Abstract

Trehalose (Tre) and salicylic acid (SA) are increasingly used to mitigate drought stress in crop plants. In this study, a pot experiment was performed to study the influence of Tre and SA applied individually or in combination on the growth, photosynthesis, and antioxidant responses of sweet basil (Ocimum basilicum L.) exposed to drought stress. Basil plants were watered to 60% or 100% field capacity with or without treatment with 30 mM Tre and/or 1 mM SA. Drought negatively affected growth, physiological parameters, and antioxidant responses. Application of Tre and/or SA resulted in growth recovery, increased photosynthesis, and reduced oxidative stress. Application of Tre mitigated the detrimental effects of drought more than SA. Furthermore, co-application of Tre and SA largely eliminated the negative impact of drought by reducing oxidative stress through increased activities of antioxidant enzymes superoxide dismutase, peroxidase, and catalase, as well as the accumulation of the protective osmolytes proline and glycine betaine. Combined Tre and SA application improved water use efficiency and reduced the amount of malondialdehyde in drought-stressed plants. Our results suggested that combined application of Tre and SA may trigger defense mechanisms of sweet basil to better mitigate oxidative stress induced by drought stress, thereby improving plant growth.

Foliar Application of Trehalose or 5-Aminolevulinic Acid Improves Photosynthesis and Biomass Production in Drought Stressed Alpinia zerumbet

“…The onset of stress conditions often causes a decrease in photosynthetic and accessory pigments and/or disrupts stomatal activity [4]. As a result, the photosynthetic rate declines.…”

“…Thus, irrigated crop production faces increasing threats from water shortages [3]. A strategy for sustaining crop productivity in the face of reduced water availability is to improve plant drought-stress tolerance [4].…”

“…The search continues for effective and economic strategies to minimize the deleterious effects of drought stress and increase drought tolerance in crops to help ensure sustainable productivity [4,10,11]. Exogenous applications of a variety of osmoprotectants, nutrients, plant-growth regulators, and oxidant scavengers before or at the onset of drought are considered to be beneficial in mitigating the negative effects of drought on plant performance, thereby enhancing plant productivity [8,10,11].…”

Biochar, Compost, and Biochar–Compost Blend Applications Modulate Growth, Photosynthesis, Osmolytes, and Antioxidant System of Medicinal Plant Alpinia zerumbet

“…Plant metabolites, such as phenolics and flavonoids, are a vital group of active constituents of medicinal plants with therapeutic importance (Zulfiqar et al, 2021 ). These antioxidants play a crucial role in mitigating oxidative stress by regulating reactive oxygen species (Hasanuzzaman et al, 2020 ; Zulfiqar et al, 2021 ).…”

“…Plant metabolites, such as phenolics and flavonoids, are a vital group of active constituents of medicinal plants with therapeutic importance (Zulfiqar et al, 2021 ). These antioxidants play a crucial role in mitigating oxidative stress by regulating reactive oxygen species (Hasanuzzaman et al, 2020 ; Zulfiqar et al, 2021 ). The therapeutic properties of medicinal plants depend on these metabolites and antioxidant activity, which can be improved by amending soils with organic materials (Liu et al, 2021 ; Mehdizadeh et al, 2021 ; Nigam et al, 2021 ).…”