Abstract No-tillage (NT) is a conservation practice adopted by 60% of the Brazilian farmers. Due to unsuitable management, compaction problem reported in soils under NT has increased. The study aimed to evaluate the influence of different soil tillage and different winter cover crops in long-term on crops biomass and maize yield and on soil penetration resistance (PR), in two crop seasons. The long-term experiment is located at the UTFPR Dois Vizinhos experimental station, with a combination of five soil tillage: NT; NT chiseled up to 0.35 m deep (Jumbo), annually (NTCa) and triennially (NTCt); NT with minimum tillage chiseled up to 0.35 m deep (Terrus), annually (NTMTa) and triennially (NTMTt); and four winter cover crops: black oats, common vetch, forage radish, and a mixture of oats + vetch + radish (mix). Dry matter production of cover crops was higher in oats and the mix, and in NTMTa in both years (2021 and 2022). Soil chiseling reduces PR, however over time, an increase was observed. NT showed higher PR, especially in the 0.15-0.20 m soil layer, but it did not impact crop production. Maize yield was not influenced by cover crops or soil tillage. NT proved to be the most efficient soil management, as its performance in maize yield was similar to the others, indicating the way forward in the pursuit of a more sustainable agriculture. Notillage No (NT 60 farmers management increased longterm long term PR , (PR) seasons station 035 0 35 0.3 Jumbo, Jumbo (Jumbo) NTCa (NTCa NTCt (NTCt) Terrus, Terrus (Terrus) (NTMTa NTMTt (NTMTt) mix. mix . (mix) 2021 (202 2022. 2022 2022) time observed 0.150.20 015020 0.15 0.20 15 20 0.15-0.2 layer others agriculture 6 (PR 03 3 0. (Jumbo (NTCt (Terrus (NTMTt (mix 202 (20 150 0.150.2 01502 015 0.1 020 0.2 1 2 0.15-0. (2 0.150. 0150 01 02 0.15-0 ( 0.150 0.15-

Abstract The use of conservation practices for sustainable agriculture production has grown in the last decades, mainly due to the no-tillage and the cover crops. The aim was to evaluate the productive performance of phytomass in three crop years with the effect of different winter cover crops and nitrogen (N) rates in succession maize. The study was carried out at the Federal Technological University of Paraná, in Dois Vizinhos, between 2020 and 2023, in a long-term experiment (2010). The treatments were a combination of three N rates applied to maize and eight winter cover crops. The annual cropping systems were buckwheat-winter cover crops-maize. The dry phytomass of buckwheat showed a significant difference between the residual N rates, but no difference to the cover crops. For the winter cover crops, mix and single oats showed a higher phytomass production, especially oats+vetch+radish, while common vetch had a lower production. Phytomass of maize was responsive to N addition, regardless of crop year; however, in a dry weather year, the cover crops showed no difference. Cumulative annual phytomass ranged from 10 to 28.6 Mg ha¯1 and was related to the N rate and the winter crop. Maize grain yield was higher after vetch and lupine and with N fertilization. Therefore, winter cover crops and N fertilization can contribute to the productive development of all the crops in the cropping system. decades notillage tillage (N Paraná Vizinhos 202 2023 longterm long term 2010. 2010 . (2010) buckwheatwinter cropsmaize. cropsmaize crops-maize oatsvetchradish radish oats+vetch+radish addition year however 1 286 28 6 28. ha1 ha ha¯ Therefore system 20 201 (2010 2 (201 (20 (2 (

ABSTRACT One of the pillars of a no-tillage system is the addition of adequate amounts of residue to keep the soil continuously covered. Cover crops are a tool for supplying the demand for the permanence of residues on the soil surface and releasing nutrients to the soil. However, there is no index that relates these two factors and can reconcile the maximum permanence of crop residues in the soil with the maximum N supply via N mineralization of such residues. This study aimed to assess the effect of different cover crops on the decomposition rate of residues and N release, using the residual biomass quality index (RBQI) to evaluate cover crop systems. The study was conducted in a long-term experiment in a Latossolo Vermelho (Ferralsol, Oxisol) under no-tillage in the two agricultural years 2017/18 and 2018/19. The experiment was in a split-plot factorial scheme with eight winter cover crops and three N rates in randomized blocks with three replications. The cover crop systems were black oat (O), common vetch (V), forage radish (R), white lupine, rye, annual ryegrass, oat + vetch (O+V), and oat + vetch + radish (O+V+R). The N rates applied to the corn in succession were 0, 90, and 180 kg ha-1. The decomposition rate, remaining dry mass (RDM) on the soil surface, N release rate, and N accumulated release (NAR) were assessed using litterbags. Considering NAR and RDM evaluated for up to 105 days, the N release index (NRI) and remaining dry mass index (RDMI) were determined, and the residual biomass quality index (RBQI) was obtained using the product of these variables. The consortia O+V+R and O+V resulted in a decomposition rate and N release rate closer to the rates observed for oats and rye. The NAR was similar to that observed for Fabaceae species, and the RDM was similar or superior to that found for black oat. With these characteristics, the systems in the O+V+R and O+V consortia presented the highest values of RBQI, ranging from 0.61 to 0.90, indicating that RBQI is a potential indicator for choosing cover crop systems that promote greater sustainability of the no-tillage system. The use of N fertilizer in corn did not change the rates of decomposition and N release from the residues of cover crops. notillage tillage covered However (RBQI longterm long term Ferralsol, Ferralsol (Ferralsol Oxisol 201718 2017 18 2017/1 201819 2018 19 2018/19 splitplot split plot replications O, O , (O) V, V (V) R, R (R) lupine rye ryegrass O+V, OV (O+V) O+V+R. OVR . (O+V+R) 0 90 ha1. ha1 ha 1. 1 ha-1 (RDM (NAR litterbags 10 days NRI (NRI RDMI (RDMI determined variables species characteristics 061 61 0.6 090 0.90 20171 201 2017/ 20181 2018/1 (O (V (R (O+V (O+V+R 9 ha- 06 6 0. 09 0.9 20 2018/ 2