Zaxinone mimic-mediated seed priming enhances tomato tolerance to saline water irrigation through improved ion regulation, metabolic adjustment and oxidative stress protection

Research Hypothesis
Seed priming with Zaxinone mimics—particularly MiZax3—is hypothesized to activate integrated physiological and biochemical defense pathways in tomato, including improved ion homeostasis (↓Na⁺, ↑K⁺), enhanced metabolic stability, and elevated antioxidant enzyme activity, resulting in superior tolerance to saline water irrigation compared with conventional priming agents.

Treatments and growth conditions
The dataset includes detailed measurements from a rooftop experiment evaluating four seed‑priming treatments: distilled water (d.H₂O, control), CaCl₂ (10,000 µM), MiZax3 (15 µM), and MiZax5 (15 µM). Three salinity levels were imposed during irrigation: SI0 (tap water control), SI5 (5 dS m⁻¹), and SI10 (10 dS m⁻¹). Tomato seeds (cv. Areenez) were primed by soaking sterilized seeds in the respective solutions for 24 h. Seedlings were transplanted into 5‑L pots and irrigated manually with NaCl‑based saline solutions according to treatment.

The data covers
Morphological traits: plant height, leaf area, root length, and organ‑specific biomass.
Physiological indicators: membrane stability index (MSI), relative water content (RWC), and plant tolerance index (PTI).
Ion concentrations: Na⁺, K⁺, Ca²⁺, and the K⁺/Na⁺ ratio.
Biochemical traits: carbohydrates, proteins, amino acids, proline, and malondialdehyde (MDA).
Antioxidant enzyme activities: superoxide dismutase (SOD), ascorbate peroxidase (APX), catalase (CAT), peroxidase (POD), and polyphenol oxidase (PPO).
Flower and fruit traits: flowering time, fruit number, fruit size, total yield, and fruit quality parameters.

Key Findings
MiZax3‑primed plants showed markedly superior performance under high salinity (SI10), including higher vegetative growth, larger root systems, and improved biomass accumulation compared to CaCl₂ and non‑primed controls. Plants exhibited stronger physiological stability through higher MSI, RWC, and PTI values. Ion homeostasis improved substantially, with reduced Na⁺ uptake, greater K⁺ retention, and higher K⁺/Na⁺ ratios. Metabolic protection increased through elevated carbohydrates, proteins, amino acids, phenolics, flavonoids, and proline. Oxidative damage was minimized due to lower MDA levels and enhanced antioxidant enzyme activities (SOD, APX, CAT, POD, PPO). MiZax3 also promoted earlier flowering, better fruit set, improved fruit size and quality, and higher total yield under saline irrigation. MiZax5 showed moderate improvements, indicating partial effectiveness, while CaCl₂ provided conventional but less pronounced protection compared to MiZax3.

Interpret and Use the Data
Each row represents a priming × salinity treatment, and columns contain quantitative traits measured across replicates.

The data can be used to:
Researchers can use this dataset to investigate salt‑tolerance mechanisms, validate priming effects across other crops or environments, and guide the development of biostimulant‑based strategies for sustainable horticulture.