Use of hydrogen peroxide in acclimation of basil (Ocimum basilicum L.) to salt stress

Abstract

The aim of this study was to verify the effects of application of H2O2 on salt tolerance and oil production in basil cv. ‘Gennarode Menta’ grown in a hydroponic system. Seedlings were subjected to 3 levels of H2O2 (0, 1, and 1000 μM) in a nutrient solution during2 different exposure periods (24 and 48 h) and 2 levels of NaCl (0 and 80 mM). The plants were harvested at preflowering (at 15 days)and postflowering (at 25 days). At 25 days, the application of 1 μM H2O2/48 h and its reapplication at preflowering increased leafdry mass production compared to the other salt treatments. Relative water content decreased while leaf succulence and sclerophyllyindex increased with salinity. The increase of succulence was more pronounced with the application of H2O2. Salinity increased thechlorophylls content only in plants without the application of H2O2. Salinity increased Cl–, Na+, and organic solutes content, this effectbeing more pronounced in salt treatments that received H2O2. Essential oil content, yield, and productivity were induced by salinity andH2O2. This study shows that H2O2 application in nutrient solution for basil cultivation in hydroponic systems using brackish water is aviable technique for promoting biomass or essential oil yield.