A Transgenic Lettuce Line with Resistance to Both Lettuce Big-vein Associated Virus and Mirafiori Lettuce Virus

Abstract

The coat protein (CP) gene of lettuce big-vein associated virus (LBVaV) in sense or antisense orientation in a binary vector pBI121 was transformed via Agrobacterium tumefaciens (Smith and Towns.) Conn. mediated transformation into lettuce (Lactuca sativa L.) to generate LBVaV-resistant lettuce. Nineteen T1 lines were produced; five to 10 plants of each T1 line were inoculated with LBVaV using Olpidium brassicae (Wor.) Dang.; and LBVaV was not detected in eight plants derived from six lines. T2 seedlings from the eight plants were tested for LBVaV resistance, and one line (line A-2) with the CP gene in antisense orientation was resistant to LBVaV while the other lines were susceptible. The transgenic line A-2 was also resistant to mirafiori lettuce virus (MiLV) and big-vein expressions regardless of the presence or absence of LBVaV.