Abstract

Drought stress is one of the most important environmental factors that reduce growth, development and production of plants. Germination is one of the main growth stages, and success in this stage is dependent on moisture content of soil at time of planting. This study examined germination characteristics of four maize hybrids under four levels of osmotic potential (0, -3, -6 and -9 bar) polyethyleneglycol (PEG) 6000 using a 4 × 4 factorial experiment based on a completely randomized design (CRD) with three replications. Germination and early growth were affected by drought stress. Water potential significantly reduced germination percentage (92.8%), germination rate (69.2%), radicle length (80.3%), plumule length (85%), seedling length (83.2%) and seed vigour (98.8%). The mean germination time (70.4%) increased with decrease in the osmotic potential of PEG solution. Hybrid Simon produced the highest germination percentage, germination rate, radicle length, plumule length, seedling length and seed vigour, therefore this hybrid was the most tolerant hybrid to drought stress.

Key words: Early growth, germination, maize, polyethyleneglycol (PEG), water stress.