Effect of Salt Stress on Seed Germination, Shoot and Root Length in Basil (Ocimum basilicum)

Salinity is one of the most environmental problems in arid and semi-arid region. It is an abiotic stress factor which restricts crop production and affects development of plants. One of the these plants is basil (Ocimum basilicum). It is an annual medicinal and aromatic plant from Lamiaceae family. The present study was carried out to determine the response of different salt concentrations from 0 to 240 mM doses which increasing 20 mM. The experiment was conducted with randomized complete block design with 3 replications and placed 20 number from seeds of each plant in petri dishes. 39 petris were used consisting from 1 plant x 13 salt levels x 3 replicats. Germination tests were made at constant temperature (29±1 °C), dark field and drying oven in laboratory conditions. Appropriate test solution was placed at each petri dish being 5 ml and was changed with an interval of two days. According to the study results, germination speed and power of basil seeds completed within 3-15 days. The results noted that root lenght changed between 0.08-5.07 cm, shoot lenght changed between 0.1-5.82 cm in the basil and they changed between 10-100% germination rate between the 0-240 mM salt concentrations. The lowest germination speed and power were seen in 240 mM and the highest germination speed and power were seen in 20 mM except control condition. Germination percentage of basil seeds were decreased from 0 (control) to 240 mM. In addition to this, the highest shoot and root lenght were obtained from 20 mM and the lowest shoot and root lenght were obtained from 240 mM except control condition. Root lenght/shoot lenght was also determined changing between 0.43-1.27. According to results, it was determined that germination number and rate, shoot and root lenght were statistically affected by different salt doses. Considering different salt doses, the highest number of germination was obtained from 20 mM salt dose, the lowest value was determined in 240 mM salt application compared to control application. It is suggested that salt tolerence studies should be preferred under 200 mM salt dose to obtain the germination number and rate over 80%  in different salt doses and in order to grow the basil under salted areas.