Study on resistance ability of Aquilaria sinensis trees under artificial induction

Objective To study the effects of hormone, salt, fungi and artificial wounding induction on resistance ability of Aquilaria sinensis trees, and discover the mechanism of agarwood formation in A. sinensis trees.

Method We conducted the experiment in Huidong county, Guangdong province, and used a random block design with three single tree repeats per treatment. Six months after stimulation, stress-resistance related substances and enzyme activities were analyzed for A. sinensis tree samples.

Result Among the different treatments of hormone, salt, fungi and artificial wounding, the optimal treatments were treatment 2 (MeJA and Et), treatment 8 NaHSO₃ (w=1‰), NaCl(w=20‰) and FeCl₂ (w=10‰), treatment 10 (Trichoderma atroviride) and treatment 16 (burning-chisel-drilling). For these four treatments, the contents of essential oil were 8.48%, 9.86%, 12.46% and 6.21% respectively, approaching or reaching agarwood quality standard (10%). Polyphenol, soluble sugar content, and CAT, POD, SOD, NOS, PAL activities were higher compared to other treatments of the same treatment type, while MDA and starch contents were relatively lower. Based on principal component analysis, the scores of resistance ability of A. sinensis trees with treatment 2, 8, 10 and 16 were 1.83, 2.31, 2.10 and -1.51, respectively, all highest among the same treatment type.

Conclusion MeJA and Et, NaHSO₃ (w=1 ‰), NaCl (w=20‰) and FeCl₂ (w=10‰), Trichoderma atroviride and burning-chisel-drilling could induce strong resistance, and could promote agarwood formation of A. sinensis trees.