Combination Effect of Temperature and Salinity Stress on Germination of Different Maize (Zea mays L.) Varieties

Abstract

Temperature and salinity stress are currently spreading widely across the globe and have been proven to have a negative impact on maize (Zea mays L.) crops as early as the germination stage. However, more research must be conducted on the interactive or combined effects of salinity and temperature stress on maize germination. This study aims to determine the impact of combined temperature and salinity stress on 16 different maize varieties. The maize seeds were incubated at three different temperatures (15 °C, 20 °C, and 35 °C) and two sodium chloride (NaCl) levels (0 mM and 100 mM) simultaneously. Germination percentage, root and shoot growth, root:shoot length ratio, and seed vigor index (SVI) were recorded and analyzed. The presence of salinity reduced maize germination qualities at all three temperatures tested. However, at high 35 °C temperatures, significant reductions in germination performances were observed compared to lower temperatures with salt stress. Three varieties (V1, V10, and V16) had the best overall germination performance in all three temperatures under saline stress, while V4, V5, V12, and V14 showed higher salt tolerance at 35 °C than at lower temperatures. In conclusion, increased temperature amplifies the salt stress in maize germination, and the varietal effect influences the seed tolerance towards a combination of salt and temperature stress.