Barley Cultivar Ranking Under Long-Term Tillage Systems in a Semiarid Region.

Malt barley (Hordeum vulgare L.) production is shifting in the North American Great Plains from conventional- or clean-tillage (CT) methods to conservation- and particularly no-tillage (NT) farming practices.  Six barley cultivars were grown in southwestern North Dakota from 2010 through 2013 under long-term CT, NT, and reduced-tillage (RT) management to determine if the relative ranking changed for yield components, grain yield and quality. Ranking of cultivars did not change across tillage systems for plant density, plant height, or spike density (P > 0.05). Likewise, a tillage by cultivar interaction was not detected for grain yield, except in 2012 (P = 0.007) when dry conditions developed and persisted. That year, grain yield of the cultivars Pinnacle and Conrad were 5164 kg ha^-1 and 4967 kg ha^-1, respectively, under NT management compared with 4166 kg ha^-1 and 3725 kg ha^-1 under CT management. Yield of other cultivars was unaffected by tillage system in 2012. Tillage by cultivar interactions were detected for grain protein concentration and test weight, but one or more cultivars consistently produced grain with quality traits that were comparable or superior to those of other cultivars in each tillage system. Grain protein concentration decreased from 131 g hg^-1 under CT management to 113 g kg^-1 under NT management across years and cultivar treatments, while grain test weight sometimes was heavier under NT management. Results of this research indicate that cultivar recommendations can be extended across contrasting tillage systems when malt barley is grown in the North America Great Plains.