To address the etiological role of GRBV in the recently recognized red blotch disease of grapevine, infectious GRBV clones were engineered from the genome of each of the two previously identified phylogenetic clades for Agrobacterium tumefaciens-mediated inoculations of tissue culture-grown Vitis spp. plants. Following agroinoculation and one or two dormancy cycles, systemic GRBV infection was detected by multiplex PCR in V. vinifera exhibiting foliar disease symptoms but not in asymptomatic vines. Altogether, our agroinoculation and therapeutic experiments fulfilled Koch’s postulates and revealed the causative role of GRBV in red blotch disease.
Read more here!