Effect of PEG8000 and NaCl on germination and seedling traits of tropical maize (Zea mays L.)

Among the different types of abiotic stresses, water is the most damaging for crops. In the current research, the effect of water stress, induced with Polyethylene Glycol 8000 (PEG8000) and Sodium chloride (NaCl) solutions, was studied in maize genotypes. A randomized block design (RBD) with a factorial arrangement and four replications of 25 seeds each was used. The studied maize genotypes were RC2C39, RC2C51 (wild varieties of the State of Tabasco backcrossed with the endogamic line CML247 of the International Center for the Improvement of Maize and Wheat), wild Tamulte, VS536, and Asgrow 7573 hybrid, study osmotic pressures (OP) were 0, -1.0, and -2.0 MPa. The percentage seed germination (G%), and seedling length (SL, in cm), root length (RL, in cm), fresh seedling weight (FSW, in g), and fresh root weight (FRW, in g) were evaluated on seedlings after 12 days of treatment imposition in the five corn genotypes (Zea mays L.). The results showed significant differences in the study variables before and after the stresses as the concentrations of PEG8000 and NaCl increased. In general, the RC2C39, RC2C51, and VS536 genotypes had a better response to PEG8000 and NaCl as compared to wild Tamulte and Asgrow 7573 hybrid for all measured variables. The OP of -2.0 MPa is suggested to separate drought-tolerant from intolerant corn cultivars in the Mexican tropical areas.