The effect of mirabilis antiviral protein (MAP) in infections by Cucumber mosaic virus (CMV) and Potato virus Y (PVY) in Nicotiana benthamiana plants under greenhouse condition

In this study using with the Mirabilis antiviral protein (MAP), it was attempted to explore the MAP controlling effect mechanism as well its antiviral activity against the Cucumber mosaic virus-Fny (CMV) and Potato virus Y strain O (PVYº) under the greenhouse condition. Toward this aim, MAP was first isolated from different fractions of the crude extracts mixture of the leaves and roots of the four o'clock plant and then Nicotiana benthamiana seedlings were cultivated in 50 g pods and mechanically inoculated with the PVYO-UK (Acc.no. KY112748) and CMV-Fny (Acc.no. D00356.1) at 4 to 6 leaf stages. PVYO inoculation was also separately done by the aphid. MAP was administrated directly into the rhizosphere area of the pods at the concentration of 300 µg in two days after and two days before seedling inoculations. Infection with each of the inoculated viruses in MAP treated benthamiana plant seedlings were then assessed by DAS-ELISA, 14 days after inoculations. Using with the Real-time RT-PCR, PVYO transcript levels was assessed at this time. Results showed that soil treatments of the benthamiana plant seedling with the MAP significantly decreased the titre of the tested viruses up to 14 days after treatments. Results of the Real-time RT-PCR indicated to the significant decrease in PVYO transcript level compared with the infected control plant. It was also revealed that MAP is more effective in controlling PVYO compared to CMV-Fny. Results indicated that MAP has not inhibited the PVYO transmission by the aphid vector. The dry and wet weights and the phenol content were also increased in benthamiana plants treated with the MAP.