Variety traits

Heat tolerance of tomato

Solanum lycopersicum L.

The ability of tomato plants to maintain productivity and the integrity of the photosynthetic apparatus at temperatures above optimal, which is critically important for pollen fertility and fruit set.

In the reference 14 varieties crop Tomato, where this is mentioned in the description.

Tomato heat tolerance is evaluated by the ability to maintain stable pollen fertility and fruit set at daytime temperatures above 26 °C and nighttime temperatures above 20 °C. Highly resistant genotypes are characterized by efficient maintenance of water status, a well-developed root system, and the preservation of photosystem II activity, which prevents chlorophyll degradation and loss of turgor.

Diagnostic procedures for the trait include laboratory testing of seedlings at 35–43 °C, determination of free proline levels, membrane electrolyte leakage, and photosynthetic rate. Field evaluation is based on calculating resistance coefficients relative to classifier varieties, assessing the percentage of fruit set, and measuring morphological root parameters.

Exposure of tomato plants to high temperatures leads to pollen sterility, flower abortion, and reduced fruit quality. Accelerated respiration processes and metabolic exhaustion under stress require breeding material to possess complex adaptation at all stages of ontogenesis, as resistance during the vegetative phase does not always correlate with the reproductive phase.

General information about the subject — on the page Heat tolerance.

Sources8

Varieties of Tomato mentioned in the description

Selection based on the description text, not on official evaluation: these data are absent from registers. For specific variety details, please refer to its profile.