Resistance to Passion fruit woodiness virus in transgenic plants of the yellow passion fruit expressing the viral coat protein gene

摘要

We report here the use of the coat protein (CP) gene of Passion fruit woodiness virus (PWV), genus Potyvirus, to produce transgenic plants of passion fruit (Passiflora edulis f. flavicarpa). The CP gene of a severe PWV isolate from the State of Sao Paulo, Brazil (PWV-SP) was cloned into binary vectors pCambia 2300 and pCambia 2301, and introduced into Agrobacterium tumefaciens strain EHA 105. Transgenic plants from two cultivars, 'IAC-275' and 'IAC-277', were recovered. Integration of the PWV CP gene was confirmed in seven plant lines by Southern blot analysis, with variable number of copies. The 32 kDa PWV CP was detected by Western blot analysis in two plants. The results of three successive mechanical inoculations of the transgenic lines with three PWV isolates showed that the primary transformants T2 ('IAC-277') was immune to infection with all isolates. PWV-inoculated non-transformed plants exhibited severe mosaic symptoms 7 to 10 days after inoculation..