Effect of seed ageing on emergence and lipid peroxidation of sunflower under drought and salinity stresses

The objective of this research was to evaluate the effect of levels of seed ageing on emergence of sunflower under drought and salinity stresses. A factorial experiment was conducted based on an RCBD with three replicates in 2012. Experimental factors were factor A that consisted of environmental stress at five levels and factor B made up of seed ageing at four levels (24, 48, 72 and 96 hours). In this study, percent, speed and uniformity of emergence, 50% (D50) the time required to achieve maximum emergence, electrical conductivity of membrane, lipid peroxidation and heterotrophic growth of seedlings consisting of two components: 1) the amount of seed reserves mobilized 2) seed reserve conversion efficiency to seedling tissues, were measured. The results showed that lipid peroxidation and electrical conductivity of plasma membrane increased with increasing accelerated aging. In this experiment, traits such as percent, speed and uniformity of emergence, seedling heterotrophic growth decreased with an increase in accelerated ageing.