BREEDING OF HOP VARIETIES FOR THE FUTURE
Breeding is a neverending dynamic process. Great progress has been achieved at the Hop Research Center Huell (HRCH) in aroma and high alpha varieties. Now breeding activities have refocused on the development of innovative hop varieties contributing towards new demands and challenges in 2020 and beyond. Economic and ecological constraints, altered demands from the brewing industry, changed consumers preferences, the occurrence of new diseases and pests, and climate changes are the major driving forces for the development of new hop varieties. Some of these issues could be addressed by providing dwarf hops adapted to the growth on low-trellis systems. First crosses have been conducted to combine dwarf stature with brewing quality, broad resistance to diseases and pests and satisfying agronomic performance as well. To realize the various breeding objectives the HRCH relies on the variability of its genetic resources which are utilized and extended continuously. In these efforts classical breeding is supported by latest genome analytical findings. AFLP markers for disease resistance increase the efficiency of the selection steps. Moreover, to increase the reliability of molecular markers, at current gene expression studies using the cDNA-AFLP technique are conducted to identify genes which are involved and activated during the recognition and defense of powdery mildew. Transcript-derived fragments (TDFs) with homology to gene sequences involved in pathogen defense reactions will be used to develop very reliable and highly informative molecular markers for the selection step. Currently, genetic engineering is not accepted by the general public as a breeding tool. Thus, this technique is being used for functional analysis of genes involved in defense reactions to pathogens. After confirmation, these genes can be utilized in gene transfer as well as in classical breeding as molecular markers. The HRCH breeding program will provide innovative hop cultivars which improve and ensure that Germany is a successful, competitive and modern country for the hop industry of the 21st century.
Seigner, E., Lutz, A., Oberhollenzer, K., Seidenberger, R., Seefelder, S. and Felsenstein, F. (2009). BREEDING OF HOP VARIETIES FOR THE FUTURE. Acta Hortic. 848, 49-58
Humulus lupulus, breeding, dwarf type, low-trellis production system, resistance to powdery mildew, gene expression studies