Study of Salinity Tolerance in Four Maize (Zea Mays L.) Hybrids at Seedling Stage

Salinity stress is one of the most important abiotic stresses that effects on many agronomic, nutritional, physiological and biochemical processes of crops. A factorial experiment based on completely randomize design with four replications under laboratory conditions with four maize hybrids (SC640, SC704, SC740 and SC Simon) and three levels of salt stress (0, 100 and 200 mM NaCl) was carry out in seedling stage. Dry weight and plant height of maize seedlings significantly decreased under salinity stress, so SC 704 and SC-Simon showed significantly smaller reduction than SC640 and SC740 under salinity stress. Salt stress was declined chlorophyll a, chlorophyll b and total chlorophyll compared with control. Anthocyanin and carotenoid were different responses to salinity stress. Relative water content (RWC) was decreased under salinity stress, but between maize hybrids were not differed significantly from this water relation attribute. K increased in all maize hybrid seedlings, accumulation of K dependent to Na influx. In other words, the hybrids that accurate high Na was have more K content. Glycine betaine and proline contents were enhanced under salt stress. SC 704 and SC Simon were tolerant to salinity.