Crop rotation and inoculation increase soil bradyrhizobia population, soybean grain yields, and profitability

Crop rotation and rhizobial inoculation are strategies to increase yield by means of organic matter addition and modulation of microbial diversity. However, the extent to which these agricultural practices change soil Bradyrhizobium populations, soybean grain yield, and economic benefits to farmers is unclear. Thus, this study aimed to evaluate the interaction between crop rotation and inoculation of soybean (Glycine max) cultivated in two contrasting soils (clayey and sandy soil) on biological nitrogen fixation components, grain yields, and profits. Field experiments with a three-year crop rotation system were carried out to compare effects of inoculation and crop rotations on soil chemical attributes, bradyrhizobia most probable number (MPN) and diversity, soybean nodulation, grain yield, and economic indicators of inoculation in different crop rotations. The crop rotation did not affect the soil MPN cells of bradyrhizobia, but the inoculation and the soil sampling time did, ranging from 3.61-4.42 to 4.40-4.82 in the sandy soil, while in the clayey soil they were from 5.19-6.34 to 6.61-7.14 in Log10 per g of soil with higher population after harvest of summer crops. In the clayey soil, crop rotation influenced soybean nodulation. The grain yield of inoculated soybean in the clayey soil was higher than that in the sandy soil. Soybean inoculation with Bradyrhizobium spp. increased the profitability of agricultural production systems by up to 45% in clayey soil and up to 7% in sandy soil.

The diversification of species in crop rotation increases the profitability of grain production systems

Crop rotation with species diversification contributes to the control of pests, diseases and weeds and improves soil fertility and conservation, which can lead to increased profitability in grain production systems. The objectives of this study were to determine whether grain production systems that employ crop rotation with species diversification are more productive and profitable than double-cropping rotations without diversification and to analyze the revenues and production costs of these cropping systems. An experiment was conducted in a region with subtropical climate between the crop years of 2014-2015 and 2019-2020. The experiment consisted of a randomized block design with six treatments and four replicates. The treatments consisted of six grain production systems, including five rotations with varied levels of species diversification and a corn-soybean rotation without species diversification, all under no-tillage. Productivity, revenue, production cost and profit indicators were analyzed. Productivity was compared by Duncan's test (p ≤ 0.05). The grain production systems with species diversification showed better productivity and profitability than the corn-soybean system. The profit of the systems with species diversification was on average 37% higher than that of the system with corn-soybean rotation. In summary, grain production systems that employ crop rotation with species diversification showed higher productivity and profitability than the corn-soybean rotation without species diversification.

Production and profitability of diversified agricultural systems

Diversified crop rotation is an option for expanding producer incomes, and its adoption has presented a series of agronomic advantages compared to less diversified crop rotation systems. In this context, the objective of this study was to verify if higher-diversified crop rotation systems perform economically better than low-diversified ones. To this end, we conducted an experiment in no-tillage crop areas in Londrina, in south of Brazil, for the years 2014/15 to 2016/17. The experiment design was randomized blocks, with six treatments, consisting of crop rotation systems with different levels of diversification, and four replications. We observed that higher-diversified crop rotation systems yield higher revenues and profits. Only these systems, specifically the ones that included canola-corn, crambe-corn, and safflower-soybeans, or wheat-corn+brachiaria, canola-corn, and edible beans-soybeans were economically feasible. Despite higher cost, diversified systems with a greater number of commercial crops in winter presented higher profits. However, diversified systems with a high proportion of cover crops in winter are economically infeasible because their net return is negative.

The dynamics of coffee production in Brazil

Coffee is a crop of significant importance for Brazilian agrobusiness. There is evidence that both the geographic distribution of coffee production, and the varieties of coffee produced, have changed throughout Brazil over the course of time. Furthermore, it appears that these developments are associated with structural changes resulting from reductions in government intervention and its effects on prices in the coffee market, which has established a new dynamic of coffee production in the country. In this context, this study's objective is to analyze the dynamics of coffee production in Brazil, to identify the Brazilian micro-regions specializing in coffee activities, and to track how the spatial distribution of these micro-regions has varied over time. In so doing, the study aims to identify defining economic characteristics of primary coffee-producing regions. Drawing primarily on data from the Brazilian Institute of Geography and Statistics, the study proceeds by applying Pearson correlation, Granger causality test, location quotient, principal components, and clustering analyses to explore how, during the 1984-2015 period, significant changes occurred in the distribution of regions specializing in coffee production. States such as Paraná and São Paulo, historically important coffee producers, declined in importance, leaving only a few micro-regions in these states specialized in coffee production. During the 2014/15 biennium, 80% of the coffee-specialized micro-regions were concentrated in the states of Minas Gerais, Bahia, Rondônia, and Espírito Santo. Minas Gerais and Bahia primarily produced arabica coffee, while Rondônia specialized in conilon (robusta) coffee. Overall, coffee produced in Brazil improved in quality and value-added over this period.

Technical and economic indicators of milk production systems in the Caiuá sandstone region

  The aim of this study was to analyze technical and economic indicators of family milk production systems, with different technology levels, in the Caiuá sandstone area in Northwestern Paraná, Brazil. The analysis period covers the agricultural years 2002/2003 to 2013/2014. The categorization of the milk production systems was based on information from agricultural farms monitored by the Reference Network for Family Agriculture. The cost-benefit analysis method was used for the economic assessment of milk production. Based on the results, three family milk production systems were identified in the region, characterized by the use of low, medium and high intensification technologies for pasture management. The production costs per unit area were found to be higher in the system with high technology and lower in the system with low technology. However, although the total revenue in the production system with a high technological intensification is greater than in the other systems, the capital needed for a technological transition is higher. In all the systems, when the costs were deducted, including the return on family labor, there was a profit, even with the climate and soil constraints inherent in the region.