ABSTRACT
High concentration of salts in the soil impacts the availability of water and nutrients essential for plant growth and physiology. Therefore, management strategies that can mitigate the negative effects of salt stress are necessary, such as the use of plant hormones. Thus, this study aimed to evaluate the effect of salt stress and the application of melatonin on the growth and production aspects of radish plants. The experiment was carried out in a randomized block design, in a 3 × 3 factorial scheme, with four replications, considering one plant per experimental plot. The treatments consisted of three electrical conductivities of irrigation water - ECw (0.5, 2.75, and 5.0 dS m-1) and three concentrations of melatonin (0, 0.5, and 1.0 mM). Growth variables were evaluated, namely plant height, stem diameter, number of leaves, leaf area, dry mass of leaves, petioles and roots, specific leaf area, leaf area ratio, and leaf weight ratio. In addition, production aspects were analyzed, namely bulb length, bulb diameter, and bulb fresh weight. Exogenous application of melatonin reduces the deleterious effects of salt stress on the growth and production aspects of radish plants. Application of melatonin at a dose of 0.5 mM is the most recommended to mitigate the effects of salt stress up to the level of 2.75 dS m-1. The use of melatonin opens new perspectives for the development of management strategies aimed at optimizing growth and protecting the radish crop under saline conditions.
Key words:
Raphanus sativus L.; Brassicaceae; phytohormones; abiotic stresses; salinity
HIGHLIGHTS:
Application of melatonin mitigates the deleterious effects of salt stress on the growth and pro-duction of radish plants.
Melatonin is a potential attenuator of moderate salt stress (2.75 dS m-1) in radish plants.
Melatonin can be used to optimize growth and protect radish plants under saline conditions.
Thumbnail
Thumbnail
Thumbnail
Thumbnail
Thumbnail
Thumbnail
Means followed by the same lowercase letters do not differ for melatonin, and means followed by the same uppercase letters do not differ from each other for salt stress according to the Tukey’s test (p ≤ 0.05)
Means followed by the same lowercase letters do not differ for melatonin, and means followed by the same uppercase letters do not differ from each other for salt stress according to the Tukey’s test (p ≤ 0.05)
Means followed by the same lowercase letters do not differ for melatonin, and means followed by the same uppercase letters do not differ from each other for salt stress according to the Tukey’s test (p ≤ 0.05)
Means followed by the same lowercase letters do not differ for melatonin, and means followed by the same uppercase letters do not differ from each other for salt stress according to the Tukey’s test (p ≤ 0.05)
