Dose-dependent effects of gamma irradiation on growth and reproductive traits of strawberry.

BACKGROUND

Radiosensitivity tests must be performed to determine the ideal doses before using gamma irradiation. This study investigated the effects of varying doses of gamma radiation (0, 10, 20, 30, 40, 50, 60, 70, 80, 90, and 100 Gy) on the growth and reproductive development of strawberry plants.

RESULTS

Gamma irradiation exhibited a clear dose-dependent response in strawberry plants, with 30 Gy producing the most favorable responses for several vegetative and reproductive traits. At 30 Gy, plants showed the highest leaf area, flower number (16.66 flowers plant⁻¹), root length (20.66 cm), and leaf fresh and dry weights (2.69 and 0.83 g, respectively). In contrast, doses ≥ 60 Gy markedly reduced survival and most growth and reproductive parameters, with severe effects at 80-100 Gy. The estimated LD25, LD50, and LD75 values were 23.6, 51.7, and 79.8 Gy, respectively, providing a quantitative radiosensitivity profile for dose selection in subsequent gamma-induced mutation-breeding experiments.

CONCLUSIONS

These results demonstrate that the moderate gamma-ray dose (30 Gy) produced the most favorable growth, root development, and flowering responses in strawberry, indicating a possible hormetic effect. Doses above 50 Gy markedly reduced survival and growth, identifying them as potential candidate doses for subsequent mutation-breeding studies, pending confirmation of heritable genetic variation.