Influence of Nitrogen Application Rate and Meteorological Conditions on β-Glucan Content in Naked and Husked Oat Grain

The objective of this study was to determine the effect of applied nitrogen fertilizer rate on β-glucan content in oat (Avena sativa L.) grains. The study was carried out at the State Stende Cereal Breeding Institute from 2011 to 2014. Three nitrogen surface fertiliser treatments (80, 120 and 160 kg·ha^-1) were applied on one husked oat (variety 'Lizete') and two naked oat genotypes (breeding lines 'S-156' and '33793'). The content of β-glucan in naked oat genotypes was significantly (p < 0.05) higher than in the husked genotype. The difference in β-glucan content between the naked breeding lines was not significant (p > 0.05). Significant (p < 0.05) differences in β-glucan content were observed between nitrogen treatments only for husked oat genotype 'Lizete'. Effect of growing season on β-glucan content was significant (p < 0.05) for both (naked and husked) oat genotypes. β-glucan content of naked oat breeding lines ('S-156' and '33793') was significantly (p < 0.05) higher in 2011 comparing with 2012 and 2013, due to differences in precipitation during the grain filling period.