Several studies seek to identify management systems that promote an increase in soil quality. As such, the aim of this study was to evaluate the effect of combinations of herbaceous and woody legumes on the productivity of green maize and the chemical attributes of the soil. The research was developed over two crop years (2016 and 2017). The experimental design was of randomized complete blocks with three replications and subdivided plots, in a 2 × 5 factorial scheme, representing the presence and absence of an alley cropping system with gliricidia, and five intercrops of maize with legumes: Maize + jack bean planted at the same time; maize + pigeon pea planted at the same time; maize + velvet bean planted 15 days after the maize; maize + Crotalaria juncea planted at the same time; single maize crop. The alley system increases the total and commercial productivity of husked cobs in maize intercropped with velvet bean. Intercropping maize with legumes under an alley system helps to increase the levels of phosphorus and potassium in the soil. Irrespective of the type of intercrop, green manure with legumes increases the soil organic matter content of farmed land in Roraima.

The use of organic fertilizers in adequate doses is an alternative to reduce the use of inorganic inputs, improving the soil chemical attributes, and increasing the production and quality of sweet potato. In this perspective, the objectives of this study were: (i) to evaluate the effects of fertilization with poultry and bovine manure, Ribumin®, and of conventional fertilization on soil attributes, production, and quality of sweet potato; and (ii) to evaluate the residual effect of organic fertilization on the production components and quality of sweet potato, in the second crop cycle. The two experiments were developed in the 2018/2019 crop year at the Agrotechnical School of the Federal University of Roraima (UFRR), Brazil. The treatments were arranged in a randomized block design with three replications, using a (2 × 5 × 2) + 1 factorial arrangement referring to two manure sources (bovine and poultry manure) and five doses, aiming at increasing the content of soil organic matter (1.35%) to 2.35; 3.35; 4.35, and 5.35%, in the absence and presence of Ribumin®, and an additional treatment referring to organomineral fertilization. For the evaluation of the second cycle, the residual effect of the manure was evaluated by applying only Ribumin® and conventional fertilizers. In the first cycle, the addition of 50.4 t ha-1 of bovine manure without Ribumin® provided the highest values of total (14.7 t ha-1) and marketable yield (14.6 t ha-1). However, the addition of poultry manure associated with the application of Ribumin® provided no increments in the sweet potato production components. Under the same experimental conditions, chemical fertilization can be replaced by fertilization with organic sources.

Cabbage cultivation with organic inputs in agroforestry systems may be an alternative for cultivation in the state of Roraima. In this context, the objective of this study was to evaluate the effects of bovine biofertilizer and alley system on the production components of Sooshu hybrid cabbage. The experiment was conducted from August 2019 to July 2020 at the Agrotechnical School of the Federal University of Roraima. The treatments were arranged in randomized blocks, in split plots, with three replicates. The factorial scheme used was 2 × 5, referring to production in systems without and with alleys and five concentrations of bovine biofertilizer (0, 25, 50, 75 and 100% of the 8 L m-2 dose). After 113 days of application of the bovine biofertilizer, the following were evaluated: i) mass of the leaves that form the head; ii) number of outer leaves; iii) mass of outer leaves; iv) transverse and longitudinal diameters and v) yield. The agroforestry system had no influence on cabbage production components. Bovine biofertilizer at concentration of 63.13% promoted higher mass of leaves that form the head and yield of Sooshu hybrid cabbage.