ABSTRACT Increasing soybean yield in the MATOPIBA region can be attributed to fertility management, which is crucial to achieving maximum agronomic efficiency. Therefore, the proper management begins with the assessment of plant nutrition. This study aimed to evaluate soybean nutritional status in western Bahia using the Diagnosis and Recommendation Integrated System (DRIS). Database comprised 153 samples from commercial fields located in the research area. To carry out the evaluation using the DRIS method, the database contained information on nutritional levels and leaf productivity of the sampled areas. Database was divided into high-productivity populations (reference population) and low-productivity populations, based on the inflection point value of the cumulative cubic function of yield. The DRIS method allowed for evaluating the potential response to fertilization; however, this method was inefficient in recommending fertilizer doses in both subpopulations. For the sufficiency levels proposed by DRIS, the nutrients N, K, Ca, Mg and S had their maximum and minimum limits reduced, while Cu, Fe and Zn had their ranges of sufficiency expanded, when compared with ranges proposed by other authors. In addition, Zn and Mn were more limiting due to lack for the high-yield subpopulation, and P and Mn for the low-yield subpopulation. The most limiting nutrients due to excess were P and Zn for the high-yield, while K and S were limiting for the low yield subpopulation. efficiency Therefore nutrition DRIS. . (DRIS) 15 area areas highproductivity high reference population lowproductivity fertilization however subpopulations N Ca reduced Cu expanded authors addition highyield subpopulation lowyield highyield, yield, (DRIS 1

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

ABSTRACT The concept of a no-tillage system (NTS), or “Sistema Plantio Direto,” was established in Brazil from the evolution of no-tillage (NT) or “Plantio Direto,” given the edaphoclimatic conditions and the need to promote chemical, physical and biological improvements in cultivated soils. While “Plantio Direto” is a conservationist practice, “Sistema Plantio Direto” presents itself as an agricultural production system based on the simultaneous adoption of minimum soil disturbance, maintenance of permanent soil cover and crop rotation. This study reviews the concepts of “Plantio Direto” and “Sistema Plantio Direto” in the Brazilian literature and uses two case studies in Paraná State to demonstrate the practical implications of these concepts. These two terms and their variations are recurrent themes in Brazilian scientific research and the professional environment, and may occur erroneously, hindering their adoption, results and implications. Regarding the “Sistema Plantio Direto,” we highlight the need to clarify the concepts of its basic practices to parameterize and characterize this process. The definition of crop rotation, for example, requires limits on the number of species along a given time scale, thus enabling their identification. Regarding the case studies, most grain crops conducted in Paraná State did not adopt the “Sistema Plantio Direto,” mainly neglecting the component of crop rotation. Nevertheless, the use of the “no-tillage system participatory quality index” (PQI) tool can contribute to the assessment and monitoring of the quality of the “Sistema Plantio Direto.” However, it requires adjustments to differentiate the “Sistema Plantio Direto” from the “Plantio Direto.”

ABSTRACT The improvement of carbon (C) accumulation in soils has been one of the main purposes of the conservation systems in agricultural production. This study aimed to assess the long-term effect of conventional tillage (CT) and no-tillage (NT) combined with winter cover crops, black oat and oilseed radish, and fallow on C accumulation and stabilization in a very clayey Oxisol in Southern Brazil. Soil samples were collected in the 0-0.05, 0.05-0.10 and 0.10-0.20 m layers of a 26-year-old experiment. Distribution of size-class aggregates, C stock in aggregates, total C stock, and C stocks in the physical fractions, free particulate organic matter (free-POM), occluded particulate organic matter (occluded-POM) and mineral-associated organic matter (min-OM) were assessed. NT had a higher percentage of macroaggregates and C stock in this size-class, and also higher C stock in bulk soil, free-POM and occluded-POM fractions than CT in 0-0.05 m (Tukey’s test p < 0.05), due to higher input of biomass and minimum soil mobilization in NT. Oat and radish had higher C stock in macroaggregates than fallow in 0.05-0.10 m (Tukey’s test p < 0.05). Radish had the highest C stock in the free-POM (0-0.05 m). Fallow decreased the stabilization of macroaggregates and C accumulation in free-POM, due to the lower C input from aboveground biomass over the years. In conclusion, NT after 26 years improved C accumulation and stabilization, mainly in the superficial layer and in POM fractions, and winter cover crops favored the formation and stability of macroaggregates.