EFFECT OF SALT STRESS ON GERMINATION ATTRIBUTES IN MAIZE

Abstract

Water and soil salinity, in arid and semi-arid zone, is considered as one of upper most important problems that affect plant growth and development, particularly at the stage of germination and seedling growth. Therefore, this study aimed to determine the physiological changes in the viability and vigour of seeds under salt stress in maize (cv. 5018). Several concentrations (0, 21, 42, 63 and 84 mM of sodium chloride) were used. The experiment was conducted according to completely randomize design with five replications, in the laboratories of Department of Field Crops, College of Agriculture, University of Baghdad, 2012-2013. The outcome results showed certain significant differences by sodium chloride concentrations on most studied attributes. The values of each one of last day germination (3.6, 5.0, 6.4 and 6.8 day), and mean germination time (1.5, 7.3, 4.0 and 4.8 day) were increased when sodium chloride concentrations increased (0, 21, 42 and 63 mM) respectively, and the lowest value was at control treatment. Also, the values of each one of germination percentage as first count (68.4, 34.7, 9.2 and 4.8%), germination percentage as final count (84.1, 54.9, 19.2 and 13.6%), coefficient of velocity of germination (68.2, 27.1, 25.1 and 20.9 %.day-1), germination rate index (31.1, 8.7, 7.3 and 3.2 %.day-1), fresh and dry weight of plumula were decreased when sodium chloride concentrations increased, and the highest value was at control treatment. Germination didn't occur at 84 Mm of sodium chloride. There was positive significant relationship between most studied attributes (germination percentage as first and final count, coefficient of velocity of germination, germination rate index, fresh and dry weight of plumula). We concluded increasing of sodium chloride concentration in germination media lead to reduce germination percentage or completely inhibited at 84 Mm of sodium chloride. We recommend conducting further tests on several varieties of maize to know the nature of the general behavior of the attributes of germination and seedling growth over different a biotic stresses.