Germination and Early Seedling Growth of Two Salt-Tolerant Atriplex Species That Prevent Erosion in Iranian Deserts

Abstract

Two experiments were performed to determine the effects of temperature and NaCl concentration on seed germination and early seedling growth of Atriplex lentiformis and Atriplex verrucifera collected from salt deserts in Isfahan and Shiraz, Iran. These species help prevent soil erosion. Seeds were germinated from 5 to 30 °C at 5 °C intervals. Optimum temperature for seed germination in A. lentiformis and A. verrucifera was 15 and 10 °C, respectively. Germination was lowest at 30 °C for both species. Seeds were also germinated at 100–500 mMol/L NaCl at 100 mMol/L increments. Germination decreased as NaCl concentration increased from over 85 % germination at 0 mMol/L NaCl to less than 5 % germination at 500 mMol/L for A. lentiformis, and from over 60 to 0 % for A. verrucifera at the same salt concentrations. Ungerminated seeds in high NaCl concentrations had a higher percent recovery germination in distilled water than seeds in lower salt concentrations. For A. lentiformis there was 42.5 % recovery at 500 mMol NaCl, but only 13 % recovery germination at 100 mMol. Similar values were found for A. verrucifera. Early growth reflected germination responses in each experimental group. Hypocotyl length was significantly and strongly negatively correlated with salinity.