The potential of the smoke-derived compound 3-methyl-2H-furo[2,3-c]pyran-2-one as a priming agent for tomato seeds

The stimulatory role of 3-methyl-2H-furo[2,3-G-]pyran-2-one, a smoke-derived butenolide, on germination and post-germination events is well documented. Previous studies have involved germinating seeds in the continuous presence of the compound. However, commercial growers cannot exploit the potential of the butenolide for large-scale production of crops due to limited availability and environmental constraints. The present study was undertaken to assess the potential of the butenolide as a priming agent of tomato (Solanum esculentum Mill.) seeds. Flow cytometry data revealed that butenolide-primed seeds had a higher percentage of nuclei at the 4C stage than water-primed seeds. Emergence of the radicle was much faster in the primed seeds. After 36 h of imbibition, a higher percentage of the butenolide-primed seeds (22%) exhibited radicle emergence compared to the water-primed seeds (12%). While butenolide-primed seeds initially germinated more rapidly than either water-primed or unprimed seeds in a 48-h period, water-imbibed seeds reached a similar germination level as the butenolide-primed seeds by 60h of incubation. The butenolide-primed seeds produced significantly (P <= 0.05) more vigorous seedlings than water-primed seeds or seeds in the continuous presence of either water or butenolide. A gradual decrease in the seedling vigour index was recorded for both water and butenolide-primed seeds with increased seed storage at room temperature. Nevertheless, the vigour index was significantly greater in the butenolide-primed seeds than the water-primed seeds. Vigour indices were significantly (P <= 0.05) higher for the butenolide-primed seeds under various stress conditions (salinity, osmoticum or temperature) compared to control or water-primed seeds. Results of the present study suggest that the butenolide is a good seed-priming agent. Additionally, primed seeds retained the promotive effect for a considerable time. This was also the case for tomato seeds under various simulated field stress conditions.