Anti-TMV activity of CSL-gel mainly depends on the chitosan shell and calcium ion
CSL-gel promotes the expression of CML30 and the silencing ofCML30 enhances TMV infection. To further determine thatCML30 induced by calcium ion released from the CSL-gel contributes to the resistance against TMV infection, we generated the CS-gel and S-gel without LNT to eliminate the role of LNT on the anti-TMV activity. As shown in Figure 5a , at 2 dpi, the number of green fluorescent spots in the inoculated leaves of N. benthamiana treated with CS-gel was lower than that of the S-gel and water-treated plants. qPCR analysis showed that the expression levels of TMV-CP were significantly lower in the inoculated leaves ofN. benthamiana treated with CS-gel than that in the water and S-gel-treated plants (Figure 5b and 5c ). At 7 dpi, the green fluorescence signals and the number of TMV-CP transcripts of the water control group and S-gel treatment group were significantly higher than that of CS-gel control. However, there was no significant difference between the water-treated and the S-gel-treated plans on the TMV infection at 2 and 7 dpi. These findings indicated that CML30induced by CSL-gel also plays an important role in anti-TMV.