FRESENIUS ENVIRONMENTAL BULLETIN, vol.26, no.12, pp.7172-7178, 2017 (SCI-Expanded)
The present study was conducted to assess the response of lemon balm to irrigation water salinity, water deficits and excess water treatments. To assess the effects of different irrigation water salinity levels, 6 different salinity levels (EC = 0.25, 1.00, 1.50, 2.00, 4.00 and 6.00 dSm(-1)) with a sodium absorption ratio of less than 3 were used. To assess the effects of water stress, 4 different irrigation levels (75, 100, 125 and 150% of evaporation from Class-A pan) were applied. Two harvests were performed for salt and water stress treatments. Yields of salt treatments varied between 52.8-102.3 g/pot at the first harvest and between 22.3-49.8 g/pot at the second harvest. Yields of water stress treatments varied between 62.8-99.8 g/pot at the first harvest and between 35.3-55 g/pot at the second harvest. Plant heights varied between 32.3-47.3 cm at the first harvest and between 22.3-39.8 cm at the second harvest. The differences between the treatments were found to be significant in both treatments (P<0.05). It was concluded for sufficient drainage and infiltration conditions that lemon balm plants could be irrigated with irrigation waters with salinity levels up to 1.5 dS/m, SAR value of less than 3 and a leaching fraction of 20%. About 1.25 times of evaporation from Class-A pan can be applied to get the greatest yield levels.