PurposeTo verify the effect of salicylic acid (SA) on the Panax notoginseng disease resistance, and to reveal the mechanism of SA inducing P. notoginseng disease resistance.
MethodsExogenously added SA with different concentrations (0.1, 0.5, 1.0, 2.0, 4.0, and 6.0 mmol/L) to P. notoginseng and artificially inoculation of Mycocentrospora acerina (Hartig) Deighton, the diameter of the disease speckle with different treatments was measured, and the activity of defense enzymes and the expression of resistance genes in P. notoginseng were detected.
ResultsSA inhibited the germination of conidia on the leaf surface of P. notoginseng, and the germination rate decreased with the increase of SA concentration. The diameter of the disease speckle in each treatment was significantly lower than that in the control (P<0.05), and the best SA concentration was 1.0 mmol/L. The activities of catalase (CAT), peroxidase (POD), superoxide dismutase (SOD), phenylalanine ammonia lyase (PAL) and the content of proline (Pro) in leaves of P. notoginseng treated with 1.0 mmol/L SA increased compared with the control, but the malondialdehyde (MDA) content decreased, indicating that SA treatment of P. notoginseng could induce the increase of defense-related enzymes activity. Real-time fluorescence quantitative PCR analysis of P. notoginseng leaves after SA treatment showed that the expression of PnPR10-1 gene in leaves after SA treatment for three days was significantly higher than that in control (P<0.05).
ConclusionsExogenous application of SA could enhance the activity of defense enzymes and the expression of defense genes, and enhance the disease resistance of P. notoginseng. SA concentration of 1.0 mmol/L was the best treatment.
DownLoad: