Evaluation and Use of Genetic Resources in Spring Malting Barley Breeding in Lithuania

During the period 2004-2006, grain yield stability and malt quality characteristics of 47 spring barley varieties and 55 promising breeding lines from the collection of spring barley genetic resources were investigated at the Lithuanian Institute of Agriculture (LIA). The growing conditions in 2004 were fairly normal compared with the long-term mean, and the years 2005 and 2006 were rather dry. The varieties and breeding lines tested showed from medium to high variation of grain > 2.5 mm yield (CV 11.5-34.3%) and medium variation of grain yield (CV 4.39-13.33%). However, high temperatures and drought in June of 2006 caused a low grain > 2.5 mm yield (by on average 55.0-67.8%). Promising breeding lines were characterised as having higher grain yield and extract output per ha compared with barley varieties. However, the data showed that grain grading 2.5 mm should be improved for the breeding lines. Using the software STABLE we estimated the stability of malting barley quality traits in relation to weather conditions during the crop year, genotype properties for varieties and breeding lines, as well as the interactions of variety and weather conditions. The selection of lines promising in terms of grain yield, > 2.5 mm grain yield and extract yield, was based on their ability to realise the genetic potential in various growing conditions. The highest score in integral assessment of grain yield, grain > 2.5 mm yield and extract yield was identified for the varieties Tocada', Sebastian', Scarlett' and breeding lines: 7939-1, 7661-1, and 8080-4. The varieties and breeding lines that exhibited high grain stability, high grain quality and other agronomic traits were utilised in further breeding programmes.