Author/Authors :
Kabiri, Rozita Faculty of Agriculture - Ilam University, Iran , Hatami, Ali Faculty of Agriculture - Ilam University, Iran , Naghizadeh, Mehdi Faculty of Agriculture - Shahid Bahonar University of Kerman, Iran
Abstract :
Environmental stress, particularly drought stress can play an important role in reducing plant growth especially
during the germination stage in arid and semi-arid regions in Iran. For cultivation of medicinal plants in arid and
semi-arid areas, the assessment of their tolerance is very important. In this research, in order to evaluate the
effects of salicylic acid pretreatment on enhancement of seed germination and early seedling growth of
Foeniculum vulgare Mill. under drought stress, a factorial experiment based on completely randomized design
was employed. The factors were the combination of five levels of drought stress induced by poly ethylene glycol
(0, -0.1, -0.2, -0.3 and -0.4 MPa) and five concentrations of salicylic acid (0, 0.25, 0.5, 0.75 and 1 mM) with
three replicates. The results indicated that an increase in drought stress reduced germination components such as
germination percentage and rate, total biomass, seed vigor index, root length, root fresh and dry weight, shoot
length, shoot fresh and dry weight and relative water content and increased electrolyte leakage and proline
content. Salicylic acid improved germination; therefore, the average time necessary for germination decreased
under drought conditions. The seeds treated by salicylic acid, produced a higher root and shoot length, root and
shoot fresh and dry weight, total biomass and seed vigor index. Salicylic acid ameliorated the negative effects of
drought stress on fennel germination and seedling's growth. Higher concentrations of salicylic acid were more
effective than the lower ones. It seems that salicylic acid can enhance the tolerant ability of the seeds to
germination under drought stress.
Keywords :
Salicylic acid , Proline , Germination , Drought stress , Electrolyte leakage
