The utilization of winter-killed cover crops is increasing due to their benefits in intensive cropping systems based on summer cash crops. However, there is still a lack of knowledge about their management in temperate climates, where maize is planted early under conservation tillage techniques. For these conditions, here we document for the first time various agronomic effects of winter-killed cover crops under different management options. We evaluated the production, the nitrogen uptake, and the weed control of five pure winter-killed cover crop species, as well as the production of the subsequent maize and its nitrogen recovery, in four different sites. Several management options were compared (cover crop fertilization, sowing technique, and cover crop termination method). Legume cover crops (Trifolium alexandrinum L. and Vicia benghalensis L.) had a small above-ground biomass (on average 0.6 t DM ha⁻¹ in November), while for non-legumes (Avena strigosa Schreb., Sinapis alba L., and Raphanus sativus L.) the production (on average 2.4 t DM ha⁻¹, N uptake 89 kg N ha⁻¹) was higher, as well as weed control and N uptake. The difference in the above-ground biomass between the two groups of cover crops was smaller at the end of winter (0.4 Mg DM ha⁻¹), when in five out of eight site × year combinations, soil mineral N was significantly higher in a cover crop treatment compared to the no cover crop, presumably due to N release from cover crops. Cover crops did not increase maize production, and their residues did not hamper maize sowing and emergence. The recovery of cover crop N by maize was 86% for legumes and − 1% for non-legumes. We conclude that productivity, N uptake, and weed control of winter-killed cover crops (especially non-legume species) are encouraging, with no negative effects on maize yield.

由于在以夏季经济作物为基础的集约化种植系统中的益处，冬季杀死的覆盖作物的利用正在增加。然而，在温带气候条件下，人们仍然缺乏对其管理的了解，在温带气候下，玉米是在保护性耕作技术下早期种植的。对于这些条件，我们在这里首次记录了不同管理方案下冬杀覆盖作物的各种农艺效应。我们评估了四个不同地点的五种纯冬杀覆盖作物品种的产量、氮吸收和杂草控制，以及随后玉米的产量及其氮回收。比较了几种管理方案（覆盖作物施肥、播种技术和覆盖作物终止方法）。豆科覆盖作物 ( Trifolium alexandrinumL. 和Vicia benghalensis L.）的地上生物量很小（11 月平均为 0.6 t DM ha ^-1），而非豆科植物（Avena strigosa Schreb.、Sinapis alba L. 和Raphanus sativus L.）产量（平均 2.4 t DM ha ^-1，N 吸收 89 kg N ha ^-1）以及杂草控制和 N 吸收更高。冬季结束时，两组覆盖作物的地上生物量差异较小（0.4 Mg DM ha ^-1），当在八个地点×年组合中的五个中，与无覆盖作物相比，覆盖作物处理的土壤矿物质N显着高于无覆盖作物，可能是由于覆盖作物的氮释放。覆盖作物没有增加玉米产量，其残留物也没有妨碍玉米播种和出苗。玉米覆盖作物氮的回收率为 86%，豆科植物和 - 1% 非豆科植物。我们得出结论，冬季杀死的覆盖作物（尤其是非豆科植物）的生产力、氮吸收和杂草控制令人鼓舞，对玉米产量没有负面影响。