Effects of Different NaCl Doses on Morphological and Physiological Parameters in Mentha piperita L.

Abstract

Salt stress is one of the most serious limiting factors for crop growth and production. This study was carried out to evaluate the effects of salt stress in four Mentha piperita L. varieties, in greenhouse conditions. The seedlings were irrigated with ½ Hoagland nutrition solutions. Following 10 d of growth in the pots, the seedlings were subjected to salt stress with different concentrations of NaCl (0, 50 and 100 mM, respectively). Responses of the mint varieties to salt stress were evaluated using some plant growth and physiological parameters, such as plant height, root length, shoot and root fresh and dry weight, and ion concentrations in leaves, such as Na, K, Ca and Cl. Salt stress caused reduction in physiological parameters. However, this reduction was significant at 100 mM NaCl compared to 50 mM NaCl. These two concentrations of NaCl increased Na and Cl contents in leaves. However, K and Ca contents were decreased with salinity. The results showed that Mentha piperita cv. Sewiss and Granada were found more tolerant to salt stress than cv. Marokko and Citaro.