High biomass genotypes in spring barley

Abstract

SUMMARYThree experiments were carried out to measure grain and biomass yields of spring barley breeding lines and varieties. Leaf diseases were controlled by applying proprietary fungicides and in some treatments plants were supported by nets to prevent lodging. The trials, grown in 1982 and 1983, compared the grain and biomass yields of 14 breeding lines and two varieties with and without support. In a third experiment, comparing three lines and the varieties Triumph and Egmont, all the plots were supported and in addition each experimental plot was flanked by guard plots of the same genotype to minimize inter-plot competition.In the supported plots of all three experiments, three breeding lines, SB 543–3, SB 71–2 and HSB 258–93 produced significantly greater biomass yields than the mean of the varieties Triumph and Egmont. All three breeding lines were taller and had lower ratios of grain to grain + straw than the controls. Measurements were made of the accumulation of dry matter, chlorophyll content at anthesis and date of ear emergence but no single factor could be identified which was associated with increased biomass in these lines.The grain yield of the semi-dwarf, lodging-resistant variety Triumph was reduced by an average of 0·24 t/ha by the support treatment compared with the non-supported control. The results from the third experiment suggested that the yield of Triumph was reduced by inter-plot competition by about 10% in relation to the other entries in the trial.It is suggested that the high biomass lines identified here could be used as parents in a breeding programme to produce varieties with high yield if this high biomass could be combined with a high ratio of grain to above-ground dry-matter yield.