Assessing Influence of Ozone in Tomato Seed Dormancy Alleviation

Abstract

The study was made on the role of ozone (O 3) gas treatment on seeds of Lycopersicon esculentum cv. PKM1 (tomato) to release dormancy in advance. The experimental conditions followed a complete factorial design with 3 independent factors, i.e. A faster start of germination in T 2 treatment (98%-99%) was observed than in other treatments (T 1, T 3 and T 4) compared to control seeds by measuring seedling growth rate on 5th day after treatment. Never the less a too long and high concentration of O 3 treatment seemed to be penalizing on germination rate whereas low O 3 concentration (T 2) for a moderate time interval (20 min) seemed to be most beneficial. The treated seeds were stored, checked 1, 3, 6 months later and found that, the seeds have retained their accelerated germination efficiency. In particular 1T 2 (1 month storage), 3T 2 (3 month storage) had maximum germination rate among all the stored treated seeds, but 6T 2 (6 month storage) didn't show sustained germination acceleration efficiency. Therefore it was found that when time prolongs, O 3 treatment loss its effect steadily and the germination efficiency of all the treatments are more or less same at six months after treatment. It is hypothesized that the application of O 3 acts as an important phenomenon in accelerating seed germination by breaking the dormancy in advance which is associated with reduced level of ABA in O 3 treated seeds.