Optimizing Seed Germination of Acacia crassicarpa by Scarification and Plasma Fine Bubbles Treatments

The availability of appropriate methods to increase germination capacity (GC), thereby increasing the growth and vigor of seedlings in the nursery, plays an important role in the success of tree planting in industrial plantation forests. The aim of this research was to determine the effect of scarification and plasma fine bubbles (PFBs) treatments on the GC, viability, and vigor of Acacia crassicarpa A. Cunn. Ex Benth. seeds, one of the important acacias trees in industrial plantation forests. A completely randomized design with two factors, namely, scarification (soaking in 80°C to cold water for 24 h and 96% H2SO4 for 15, 20, and 25 min) and PFBs water treatment with ozone concentrations of 2 and 3 ppm for 5 and 10 min was used. Our study showed that the combination of scarification with H2SO4 solution for 25 min and 3 ppm PFBs water for 10 min gave the highest GC (90.75%), germination rate (GR) (20.28% days−1), and germination value (GV) (1.41). This combination also provided better results compared with methods widely used in industrial plantation forests by increasing GC 76.2%, GR 103.1%, and GV 291.7% and increasing hypocotyl length from 3.76 cm to 6.15 cm, radicle length from 2.24 cm to 6.31 cm, normal seedling length from 6.11 cm to 12.20 cm, and vigor index (VI) from 1.2 to 11.07 compared with control. This combination has been proven to increase germination, growth, and vigor of A. crassicarpa seeds; therefore, this treatment combination is recommended for use at the operational level of industrial plantation forests