Progress in the development of garden Asparagus resistant to Asparagus virus 1 (AV-1)

Progress in the Development of Garden Asparagus Resistant to Asparagus virus 1 (AV-1) T. Nothnagel, R. Krämer, H. Budahn, O. Schrader, D. Ulrich, I.Krämer and E. Schliephake Keywords: interspecific hybridisation, dpRAPD marker, electrical penetration graph, ELISA, RT-PCR, Myzus persicae, volatiles Viruses are an underestimated problem in asparagus production because infested plants are mostly inconspicuous or symptomless. Currently, ten viruses have been identified in garden asparagus (Asparagus officinalis) worldwide, of which the Asparagus virus 1 and 2 (AV-1, AV-2) and the Cucumber mosaic virus (CMV) may be economically important by decreasing vigour, yield and quality as well as increasing the susceptibility to fungal diseases and abiotic stress. Various studies assumed that between 70% and 90% of asparagus fields in Germany are contaminated with AV-1, AV-2 and CMV. A resistance against AV-1 was evaluated within the wild relative Asparagus amarus DC., and a backcross programme was started for transmission of the AV-1 resistance from the wild relative into the genome of garden asparagus. Recent results will be presented with main focus on: i – description of the resistance source, ii - interspecific hybridisation and overcoming of crossing barriers, iii – chromosomal status and meiosis behaviour, iiii - determination of the resistance status and sensory quality.