Salinity distribution pattern and its induced adaptability of tomato roots

Abstract

Salinity is a major abiotic stress and threat to tomato production. Roots can attenuate salt stress at a specific salinity concentration, especially with non-uniform salinity distribution conditions, and may play a role in enhancing tomato plant adaptability to salt stress. Salt stress will also have a certain impact on root growth, which in turn affects the adaptability of crops to salt stress. Under different salt gradients, if we can find a reasonable distribution strategy, we can increase the tolerance of plants to salt stress. The hydroponics method was used and the roots were split into left and right parts. We established different salinity distribution patterns: a uniform salinity distribution T1 [0, 0], T2 [0.2%, 0.2%], and T3 [0.3%, 0.3%] and a non-uniform salinity distribution T4 [0.1%, 0.3%], T5 [0.1%, 0.5%], T6 [0.2%, 0.4%]. We observed the whole growth stage, and the plant's physiological responses to salt stress were measured. The data indicated that tomato plant roots can attenuate salt stress at a salinity concentration of 0.4%. The non-uniform salinity distribution can restrict root-uptake and uptake efficiency of nutrients (Na+, K+). Fruit yield, flavor and quality were enhanced by the non-uniform salinity distribution of T4 [0.1%, 0.3%]. Increased K+ led to a decreased Na/K ratio, which could reduce the toxicity of salt ions and improve tomato growth. The antioxidant enzyme activities of both roots and leaves of tomato plants were elevated under different salt stress patterns, indicating that the subject plants have the potential to exert adversity adaptations and that the enzyme activities are responsive to the degree of salt stress. Response of tomato fruiting stage growth and development and yield quality to different salt stresses. Growth adaptation of tomato under salt stress conditions. The above issues are discussed to provide a theoretical basis for the salt tolerance mechanism of tomatoes under non-uniform salt stress and the growth status of tomatoes on saline soils.