Effect of PEG Induced Drought Stress on Seed Germination and Seedling Characters of Maize (Zea mays L.) Genotypes

Abstract

Drought stress is one of the most important environmental issues that reduce growth, development and yield of the plants. Developing maize cultivars that can perform well in drought and other abiotic stress is an important goal throughout the world. Germination is one of the main growth stages for seedling establishment, and success in this stage is dependent on moisture availability in the soil. A laboratory experiment was conducted to evaluate the germination characteristics of four maize genotypes under four levels of osmotic stress (0, -2, -4 and -6 bar). Polyethylene glycol (PEG) 6000 was used as an osmoticum. This investigation was performed as factorial experiment under Completely Randomized Design (CRD) with three replications. Germination and early growth were affected by drought stress. Results showed that water stress treatments significantly (P<0.05) influenced the Emergence Percentage (EP) (%), Promptness Index (PI) (%), Germination Stress Tolerance Index (GSTI) (%), Plant Height Stress Index (PHSI) (%), Root Length Stress Index (RLSI) (%), Primary root length, Number of seminal root, Seminal root length and seed vigour (%) of different cultivars of maize i.e., VIM455, VIM147, VIM213 and VIM396. The result of this experiment indicated that the two maize genotypesVIM147 and VIM396exhibited tolerance against drought stress compared to VIM455 and VIM213. The variation among genotypes for germination stress tolerance index (GSI) and Root length stress index (RLSI) was found to be a reliable indicator to screen the drought tolerant genotypes at germination and seedling stage in maize. Introduction