Physiological screening for drought tolerance in Mediterranean long-storage tomato

Area of Science:

• Plant physiology
• Drought tolerance mechanisms
• Agricultural science

Background:

• Long-storage tomatoes are traditionally cultivated without irrigation in Italian semi-arid regions.
• Understanding drought tolerance is crucial for crop productivity in water-limited environments.

Purpose of the Study:

• To screen long-storage tomato lines for low soil water tolerance.
• To investigate physiological traits related to drought tolerance and yield.
• To identify reliable indicators for predicting yield under water restriction.

Main Methods:

• Screening of ten long-storage tomato lines under no irrigation.
• Measurement of leaf relative water content (RWC), proline content, and leaf transpiration (E).
• Calculation of instantaneous leaf water use efficiency (A/E).

Main Results:

• Positive correlations were found between leaf transpiration (E) and RWC.
• Inverse relationships were observed between RWC/E and proline content.
• Proline concentration indicates water stress tolerance; less proline suggests higher sensitivity.
• Fruit yield showed significant linear relationships with RWC, E, and proline.
• Leaf transpiration rate at flowering was the most reliable predictor of yield under water restriction.

Conclusions:

• Proline accumulation is a key mechanism for drought tolerance in long-storage tomatoes.
• Leaf transpiration rate is a critical physiological trait for yield prediction in water-stressed conditions.
• This study elucidates the complex interplay between physiological processes, drought tolerance, and productivity in tomatoes.