Effects of different neutral and alkaline salinities on seed germination and early seedling growth of maize (Zea mays L.)

The effects of different types and levels of salinity on seed germination and early seedling growth of maize (Zea mays L.) were investigated. Seeds were germinated at 25 degrees C in solutions containing NaCl, KCl, Na2SO4, K2SO4, Na2CO3, NaHCO3, K2CO3 and KHCO3 at concentrations of 0 (control), 20, 50, 100, 150 and 200 mmol.L-1. The results indicated that salinity type and concentration had a significant effect on seed germination and early growth (p<0.05). Seedling stage was much more sensitive to salinity than germination stage. Sulphate salinities were more deleterious than chloride salinities, sodium salinities than potassium salinities, alkaline salinities than neutral salinities, and bivalent salinities than monovalent salinities, at seedling stage. Neutral salinities of all levels and alkaline salinities below 50 mmol.L-1 inhibited seedling growth more than root growth, while the reverse was true for alkaline salinities above 100 mmol.L-1. However, further experiments regarding the reciprocal effects of several salinities should also be conducted to draw an overall conclusion.