Tab. 1.3: Overview of PM-resistance testing in 2014 with 11 previously characterised PM isolates 2014
Greenhouse tests Plants
Assessments
Laboratory tests Plants
Assessments
-
1.356
Seedlings from 97 crosses Approx. 220,000 by mass screening Breeding lines
180
810
170
Cultivars
14
70
6
37
Wild hops
34
168
34
98
-
-
11
646
228
1,048
221
2,137
Virulence properties of the PM isolates Total (individual tests)
Mass screening in trays; individual tests = selection of individual plants in pots
Meristem cultures to eliminate viruses – faster provision of virus-free planting stock Sponsored by:
Project managers: Project staff: Cooperation: Duration:
Bayerische Landesanstalt für Landwirtschaft, Institut für Pflanzenbau und Pflanzenzüchtung, AG Züchtungsforschung Hopfen (Bavarian State Research Center for Agriculture, Institute for Crop Science and Plant Breeding, WG Hop Breeding Research) Financed by: Wissenschaftliche Station für Brauerei in München e.V. (Scientific Station for Brewing in Munich) Dr. E. Seigner and A. Lutz B. Haugg Dr. L. Seigner and IPS 2c team 01.07.2014 – 31.12.2015
Objective Virus-free hop planting stock has been an important part of our quality drive for years. The findings from virus and viroid monitoring in Germany’s hop-growing areas and the Hüll breeding yards (Seigner et al., 2014) clearly show how important meristem culture is for the provision of virus-free planting stock, both for German hop growers and for Hüll breeding work. The aim of this project is to significantly speed up the provision of virus-free hop plants. Method To produce virus-free hop plants, the shoot tips are first heat-treated prior to excision of the uppermost growth zone (= meristem), located at the apex of the shoot. These meristems regenerate to complete plants on special culture media.
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