The effect of salinity and high boron on growth, photosynthetic activity and mineral contents of two ornamental shrubs
S. Bañón, J. Miralles, J. Ochoa, M.J. Sánchez-Blancohttps://doi.org/10.17221/167/2011-HORTSCICitation:Bañón S., Miralles J., Ochoa J., Sánchez-Blanco M.J. (2012): The effect of salinity and high boron on growth, photosynthetic activity and mineral contents of two ornamental shrubs. Hort. Sci. (Prague), 39: 188-194.
Simultaneous salinity and boron (B) excess often occur due to irrigation with water containing high levels of salts, including B. The effects of excess of NaCl and B in the nutrient solution on some agronomical and physiological parameters of Viburnum tinus (laurustinus) and Metrosideros excelsa (metrosideros) were studied. Potted plants were grown in a factorial combination of B (1 and 6 mg/l) and NaCl (2 and 6 dS/m). B toxicity (6 mg/l) caused tip/edge burn in the lower leaves of laurustinus, while these symptoms were absent in metrosideros. Toxicity by B reduced dry biomass in the two species, particularly the aerial part in metrosideros and the roots in laurustinus. Metrosideros accumulated a similar content of B in all leaves, while the laurustinus tended to accumulate more B in the lower leaves. The leaf B content in laurustinus was reduced by salinity to a greater extent than in metrosideros; however, this was not sufficient to prevent injuries to the laurustinus photosynthetic system.Keywords:
boron toxicity; NaCl; laurustinus; metrosideros; chlorophyll fluorescence