sp. YJM-2013 induces ginsenosides biosynthesis in adventitious roots by inducing plant resistance responses.

Objective: is a common pathogenic fungus in ginseng cultivation. Both pathogens and antagonistic fungi have been reported to induce plant resistance responses, thereby promoting the accumulation of secondary metabolites. The purpose of this experiment is to compare the advantages of one of the two fungi, in order to screen out more effective elicitors. The mechanism of fungal elicitor-induced plant resistance response is supplemented.

Methods: A gradient dilution and the dural culture were carried out to screen strains. The test strain was identified by morphology and 18 s rDNA. The effect of different concentrations (0, 50, 100, 200, 400 mg/L) of sp. YJM-2013 and on fresh weight and ginsenosides accumulation were tested. Signal molecules transduction, expression of transcription factors and functional genes were investigated to study the induction mechanism of fungal elicitors.

Results: Antagonistic fungi of was identified as sp. YJM-2013, which reduced root biomass. The total ginsenosides content of adventitious roots reached the maximum (48.95 ± 0.97 mg/g) treated with sp. YJM-2013 at 200 mg/L, higher than control by 2.59-fold, in which protopanoxadiol-type ginsenosides (PPD) were increased by 4.57 times. Moreover, sp. YJM-2013 activated defense signaling molecules, up-regulated the expression of PgWRKY 1, 2, 3, 5, 7, 9 and functional genes in ginsenosides synthesis.

Conclusion: Compared with the pathogenic fungi , antagonistic fungi sp. YJM-2013 was more conducive to the accumulation of ginsenosides in adventitious roots. sp. YJM-2013 promoted the accumulation of ginsenosides by intensifying the generation of signal molecules, activating the expression of transcription factors and functional genes.