The Effect of Pre-Chilling and Gibberellic Acid (GA3) Treat-ments on Seed Germination and Early Establishment of Gundelia Tournefortii L.

Gundelia tournefortii is a culturally valuable wild edible plant in northern Iraq. Seed germination of Gundelia is poor due to double dormancy, making large-scale cultivation difficult. With the aim to overcome the seed dormancy of G.tournefortii for cultivation purposes, pre-sowing treatments were applied in a Randomized Complete Block Design experiment of dry pre-chilling (2°C) for durations 0, 1, 2, and 3 weeks with/without soaking seeds for 24 hours in Gibberellic acid (GA3) (0, 500, and 1000 ppm). The individual pre-chilling durations or GA3 concentrations did not have a significant effect on the germination. With increasing pre-chilling periods of up to 2 and 3 weeks, the initial root length and leaf numbers significantly increased to 5.73 cm and 6.10, respectively. GA3 only affected the total dry weight at 1000 ppm (5.1g). Pre-chilled for 1 week and then soaked in 1000 ppm of GA3, the treatment recorded the highest germination (96.25%) compared to the untreated control (62.5%). Two weeks of pre-chilling, but not soaked in GA3, showed an increase in initial root length (6.72 cm). For the initial leaf number, the highest value was recorded at three weeks with 500 ppm (7.75) compared to those not pretreated (3.25). The total dry weight was (6.485g) and (2.86g) for the three weeks with 500 ppm and non-treated seeds, respectively. Therefore, combining pre-chilling and soaking seeds in GA3 is essential. These results hold promise for scaling up Gundelia cultivation, promoting sustainable agricultural practices, and mitigating the local endangerment of this species in Nineveh Plains.