Die Bodenkultur - Journal for Land Management, Food and Environment
J. Petr, J. Lipavský and D. Hradecká:
Production Process in Old and Modern Spring Barley Varieties
Three series of experiments were carried out to study production processes of older as well as newly bred varieties of spring barley (Hordeum vulgare L. var. nutans). Special attention was paid to the variety Diamant, a short-stemmed radiomutant that laid the foundation for 173 European varieties. Special features of Diamant’s biological and economic yield formation were compared with original varieties from the region of Haná (Valticky´), with a historical variety Nürnberg from the year 1832, and with modern varieties of 1990s.
Production processes were studied by a classic growth analysis, measuring of dry matter increments and the leaf area index (LAI). The variety Diamant and varieties originating from it under conditions of Bohemia did not show any increase in total production of dry matter, however, the distribution of dry matter changed in the case of these varieties in favour of generative organs – i.e. dry matter of ears and grains. Thus, the harvest index (HI) increased to 0.40–0.44, as compared with the historical variety having HI of only 0.32. That bore also on the dynamics of dry matter creation, when these varieties showed higher increments in the generative stage than the old ones.
However, any direct relation of maximum values of LAI and the integral leaf area (LAD) during the whole growing period with the grain yield did not prove. Nevertheless, there is a relation of the integral leaf area (LAD) after earing with grain weight (with the weight of 1000 grains = TGW). In the case of the historical variety, the initial increase in the leaf area was quick, but a rapid loss of active leaf area appeared in the postfloral period.
Diamant was a donor of a short stem and higher tillering, i.e. a higher number of fertile tillers. The character of economic yield formation has changed in this way; modern varieties create the yield through the yield of tilles, the old ones through the yield of the main stem. Hence, the number of ears per area unit has changed, as well as the capacity of the sink, while showing nearly the same number of grains in an ear. Another success of breeding was also the increase in the capacity of assimilate sources to filling the higher storing capacity. Improvement of the malting quality pictures a significant genetic gain too. Protein content declined, extract increased, and also other criteria got into the optimum range of malthauses’ requirements.
The future progress in breeding will, apart of other criteria, continue in going for an increase in the harvest index, and also for a rise in the yield of total dry matter per area unit.
Key words: Hordeum vulgare L., barley, genetic improvement, yield formation, malting barley.