10-Year study on the impact of organic fertilization on winter wheat yield and quality following lucerne and grain pea in a dry sub-humid region under organic cultivation in Austria

Winter wheat (WW) plays a pivotal role in organic agriculture due to its response to various farming practices. This study assessed the impact of prolonged organic fertilization systems (FSs) on winter wheat productivity and quality in eastern Austria over a decade. We used a comprehensive dual analytical approach throughout the study. First, we evaluated three organic FSs individually: FS1 (without livestock (-L), using two-year lucerne green manure (GM)), FS2 (-L, including two-year lucerne GM and municipal compost (GM + MC)), and FS3 (with livestock (+L), including two-year lucerne forage-use and farmyard manure (FU + FYM). Second, we analyzed how FSs and preceding crops affected WW performance and quality over 10 years. Estimated biological N 2 fixation for lucerne ranged from 250 to 261 kg N ha −1 a −1 with the application of the fertilization systems FU + FYM and GM over a 10-year period. In contrast, estimated N 2 fixation for grain pea ranged from 36.2 (GM + MC) to 36.8 (FU + FYM) kg N ha −1 a −1 over the same timeframe. The simplified soil surface N-balance for lucerne ranged from −215 kg N ha-1 a-1 (FU + FYM) to 219 kg N ha-1 a-1 (GM + MC), while for grain pea, it ranged from −29 kg N ha-1 a-1 (GM) to 145 kg N ha-1 a-1 (FU + FYM). WW demonstrated higher grain DM yield (34.63 %), nitrogen yield (26.63 %), thousand kernel weight (8.91 %), and hectoliter weight (1.60 %) when grain peas were the preceding crop compared to lucerne in the rotation. Conversely, the protein content of WW was 9.80 % greater when lucerne preceded. In conclusion, the findings suggest that FS2, FS3, and peas as preceding crops demonstrate long-term potential to improve both the productivity and quality of WW in organic farming in dry regions. Future research should evaluate the economic, social, and climate resilience of organic systems in dry regions, focusing on market access, labor, and farmer perceptions. • Winter wheat in legume rotations boosts organic productivity and sustainability • Winter wheat yields higher with grain peas as preceding crop compared to lucerne • For lucerne, both GM and GM + MC treatments maintained positive N balances • For grain pea, positive N balances were maintained by GM + MC and FU + FYM treatments • FU + FYM and GM + MC boost wheat productivity and quality in dry regions