RESUMO
Considering the need for more information about productivity increases and nutritional improvement of soils, the present study evaluated the effects of alternative fertilization on grain yield and nutritional levels of bean crops. It was a randomized block study with four treatments and five replicates. The treatments were the absence of nitrogen fertilization, fertilizer use, chicken litter, and cattle manure. Organic fertilization provided lower variations in soil water availability during flowering and grain filling and increased nutrient concentrations, especially phosphorus and potassium. Chicken litter promoted the highest means for the number of legumes, the number of legumes on branches, the number of six-grain legumes, the mass of a thousand grains, grain mass per plant, and the normalized green-red difference index. However, the two organic fertilizers had significantly higher differences from chemical and no fertilization, showing that organic fertilizer applications must occur when nutrient availability coincides with the phenological stages essential for producing these fertilizers. High yields combined with favorable rainfall conditions occurred during crop development, as high soil moisture allowed faster mineralization of essential organic fertilizer nutrients, directly affecting yield. Pearson's linear correlation allowed a better understanding of the participation of each plant trait in productivity, and the highest grain yield occurred with organic fertilization.
RESUMO
The fluctuations in yield and consequently in production occurred due to climatic adversities in the main producing states of Brazil. Farming has changed over time, and past scenarios have shown high exploitation of natural resources focusing on soil tillage and conventional seeding methods. This study aimed to determine the yield performance of soybean grown under 10 consolidated crop succession systems. The experiment was conducted during the 2018/2019 crop season, before the research project entitled "Sustainable production systems with better use of biological and natural resources, with treatments arranged in a randomized block design and four replications". The treatments consisted of the following predecessor crops: Avena sativa, Avena strigosa, Triticum aestivum, Secale cereale, Brassica napus, Raphanus sativus, Avena strigosa + Raphanus sativus + Vicia sativa, Fallow, Avena strigosa + Lolium multiflorum, and Triticum aestivum Fodder. Soybean was subsequently sown across winter crops. The succession that showed superior yield was Avena strigosa + Lolium multiflorum. This attribute was established by associating taller plants with the maximization of the number of grains per pod, hundred-grain mass, grain mass, and plant dry mass; in contrast, there was a lower emphasis on plant residue. The determining attributes for soybean yield were plant stand, plant height, the number of pods per plant, and total grain mass, with contrasts among groups composed of the succession of Avena sativa, Avena strigosa, Triticum aestivum, Secale cereale, and Brassica napus, distanced from Raphanus sativus, Avena strigosa + Raphanus sativus + Vicia sativa, Fallow, Avena strigosa + Lolium multiflorum, and Triticum aestivum - Fodder.