Effect of Ozone Exposure on Water Uptake and Germination of Lentil (Lens Culinaris) Seeds

Abstract

ABSTRACT The purpose of the current study was to investigate the effect of ozone exposure on the process of water uptake and germination of lentil (Lens culinaris) seeds. For this, a commercial ozone generator that provides a concentration of 1 g/m3 generated from atmospheric air was used. In the experiments 10 lentil seeds were used per treatment carried out at different times of exposure to ozone: 2, 3, 5, 10 and 15 min. Imbibition curves were performed following the seed mass for 180 min. For germination tests, wet neutral pH germination paper was used where, every 24 h, the mass, root size and stem size of the plant were measured over 7 days. Furthermore, contact angle analysis and Fourier transform infrared spectroscopy (FT-IR) were performed on the seeds. The maximum water uptake in the seeds as a function of the imbibition time was optimum for the samples treated with 3 and 5 min. This fact was reflected in the growth rates of the stem, root and mass that were significantly higher than the control sample, after 7 days of germination. The FT-IR analysis indicated the formation of bands in 1345 cm−1 (NO3 −) related to ethylene ozonolysis. Also, it was observed a reduction of the N-H band (amide II) at 1551–1550 cm−1 and increase of the C-H bond at 1543 cm−1, evidencing a possible action of ozone on lentil proteins. This fact is probably related to the enhancement of the seed germination process, allowing the germination rates to be 90% for samples treated with ozone for 3 and 10 min.