Soil alterations by chronosequence of pastures in crop-livestock-forestry systems

The intensive use of land has accelerated the loss of soil quality, a process that can be avoided by adopting conservationist production systems, such as the Crop-Livestock-Forest Integration system – ILPF. The objective of this work was to measure the physical and chemical attributes of an Argiluvic Plinthsol under pasture chronosequence in a crop-livestock-forest integration system in Pindaré-Mirim in the state of Maranhão, Brazil. For the purpose of evaluation, the experiment contemplated two reference environments: scrubland with secondary vegetation in regeneration for approximately 20 years and native babassu forest with soils collected before the beginning of the project; and five succession times: degraded pasture (Urochloa brizantha cv. Marandu), and ILPF conducted in 2016, 2017, 2018 and 2019, also compared to reference environments. Undisturbed samples were collected in mini trenches at depths of: 0 – 10, 10 – 20, 20 – 30 and 30 – 40 cm to determine physical attributes (density, macroporosity, microporosity and total porosity). For the chemical attributes of the soil (pH, organic matter, phosphorus, aluminum, potential acidity, sum of exchangeable bases and base saturation), deformed samples were collected at the same depths. The data obtained were analyzed with the aid of descriptive statistics, analysis of variance and Tukey test at 5% significance level, and analysis of principal components and clustering. The ILPF 2019 pasture showed higher macroporosity values. For depths of 0 – 10, 10 – 20 and 30 – 40 cm, the phosphorus and base saturation variables showed higher values ​​in the 2018 ILPF.  The intensive use of land has accelerated the loss of soil quality, a process that can be avoided by adopting conservationist production systems, such as the Integrated Crop-Livestock-Forest (CLFI system). It is noteworthy that in the Southwest of the State of Maranhão a substantial portion of soils in rural properties are degraded and in distinct stages of erosion, since they have been exploited for decades with non-properly managed pastures. Therefore, the objective of this work was to emphasize the importance of physical and chemical changes in the soil of pastures under crop-livestock-forest integration in  general and in the Amazon region of state of Maranhão, Brazil. Therefore, a literature review was conducted through a search for studies in the Google Scholar database, which encompasses multiple other databases, such as Scielo, Elsevier, Scopus, Capes, and others. In face of the conditions of degradation in pastures throughout the state of Maranhão and the broad distribution of native forests such as Babassu forests, the use of technology from CLFI systems could allow for their recovery and sustainable status by means of economically and ecologically feasible productivity. Research on this field is therefore necessary to highlight short- and long-term efficiencies regarding carbon sequestration and quality of organic matter on the soil

EFEITOS DO EXTRATO DE PRÓPOLIS SOBRE A QUALIDADE SANITÁRIA E FISIOLÓGICA DE SEMENTES DE ARROZ (Oryza sativa L.) E SOJA (Glycine max (l.) Merril)

The purpose of this work was to evaluate the effect of applying different concentrations of propolis extract on the sanitary and physiological quality of rice and soybean seeds. The experiment was conducted at the Microbiology and Health Laboratory of the State University of the Tocantina Maranhão Region (UEMASUL), from January to May 2019. The experimental design was completely randomized, with six treatments and four replications of 20 seed lots.  The treatments tested were: control (distilled water), concentrations of 2.5%; 5%; 7.5% and 10% propolis extract and the Maxim fungicide (positive control). The seeds with the propolis dosages were homogenized in plastic bags and dried at room temperature under absorbent paper. Subsequently, they were plated in Petri dishes containing three previously moistened germitest sheets of paper and incubated in photoperiod BOD at an average temperature of 26 ± 1 ºC for seven days. The following parameters were evaluated: fungal incidence on treated seeds, seed germination, root length and seedling height. All concentrations of propolis extract showed efficiency in reducing fungal incidence in rice and soybean seeds, and the genera Aspergillus sp., Fusarium sp., Penicillium sp., Cercospora sp., Phomopsis sp. and Rhizopus sp. The physiological quality of seeds, regarding germination parameters, soybean seedling root length and rice seedling height were not influenced by propolis extract concentrations.El objetivo de este trabajo fue evaluar el efecto de aplicar diferentes concentraciones de extracto de propóleos en la calidad sanitaria y fisiológica de las semillas de arroz y soja. El experimento se realizó en el Laboratorio de Microbiología y Salud de la Universidad Estatal de la Región de Maranhão Tocantino (UEMASUL), de enero a mayo de 2019. El diseño experimental fue completamente al azar, con seis tratamientos y cuatro repeticiones de 20 lotes de semillas. Los tratamientos probados fueron: control (agua destilada), concentraciones de 2.5%; 5%; 7.5% y 10% de extracto de propóleo y el fungicida Maxim (control positivo). Las semillas con las dosis de propóleos se homogeneizaron en bolsas de plástico y se secaron a temperatura ambiente bajo papel absorbente. Posteriormente, se colocaron en placas de Petri que contenían tres hojas de papel germinadas previamente humedecidas y se incubaron en BOD de fotoperíodo a una temperatura promedio de 26 ± 1 ºC durante siete días. Se evaluaron los siguientes parámetros: incidencia de hongos en semillas tratadas, germinación de semillas, longitud de raíz y altura de plántula. Todas las concentraciones de extracto de propóleos mostraron eficiencia para reducir la incidencia de hongos en las semillas de arroz y soja, y los géneros Aspergillus sp., Fusarium sp., Penicillium sp., Cercospora sp., Phomopsis sp. y Rhizopus sp. La calidad fisiológica de las semillas, con respecto a los parámetros de germinación, la longitud de la raíz de las plántulas de soja y la altura de las plántulas de arroz, no fueron influenciadas por las concentraciones de extracto de propóleos.O objetivo com este trabalho foi avaliar o efeito da aplicação de diferentes concentrações de extrato de própolis sobre a qualidade sanitária e fisiológica de sementes de arroz e soja. O experimento foi conduzido no Laboratório de Microbiologia e Saúde da Universidade Estadual da Região Tocantina do Maranhão (UEMASUL), no período de Janeiro a Maio de 2019. O delineamento experimental utilizado foi inteiramente casualizado, com seis tratamentos e quatro repetições de lotes de 20 sementes. Os tratamentos testados foram: testemunha (água destilada), concentrações de 2,5%; 5%; 7,5% e 10% de extrato de própolis e o fungicida Maxim (controle positivo). As sementes com as dosagens de própolis foram homogeneizadas em sacos plásticos e secas à temperatura ambiente sob papel absorvente. Na sequência, foram plaqueadas em placas de Petri, contendo três folhas de papel germitest previamente umedecidas e incubadas em BOD com fotoperíodo, à temperatura média de 26±1 ºC durante sete dias. Foram avaliados os parâmetros: incidência fúngica nas sementes tratadas, germinação de sementes, comprimento da raiz e altura da plântula. Todas as concentrações de extrato de própolis apresentaram eficiência na redução de incidência fúngica nas sementes de arroz e soja, sendo identificados os gêneros Aspergillus sp., Fusarium sp., Penicillium sp., Cercospora sp., Phomopsis sp. e Rhizopus sp. A qualidade fisiológica das sementes, quanto aos parâmetros de germinação, comprimento de raiz de plântulas de soja e altura de plântulas de arroz, não foram influenciadas pelas concentrações de extrato de própolis

EFFECT OF APPLYING MIXED ORGANOMINERAL FERTILIZER AS A BIOSTIMULANT ON SOYBEAN YIELD

Although soybean is economically one of the main agricultural products in the national and world scenario, it is still needed to increase its grain yield. Therefore, this study aimed to evaluate the effect of applying mixed organomineral fertilizer (OMF) at different doses and at two phenological stages on soybean yield. The experiment was conducted in the experimental area of the Federal University of Jataí, in the state of Goiás, and was installed under a no-till system (NTS). The experimental design used was randomized blocks arranged in a 4 x 2 + 1 factorial scheme, consisting of four doses of OMF, applied at two phenological stages and one additional control. The following OMF doses were evaluated: 0.5 kg ha-1, 1 kg ha-1, 1.5 kg ha-1, and 2 kg ha-1, at two reproductive stages: R3 and R5, and the additional control. The experiment consisted of three blocks. Each plot had a useful area of 16.2 m². The agronomic parameters assessed were plant height (m), first pod insertion height (m), number of pods per plant, number of grains per pod, 1000-grain mass (g), and grain yield (kg ha-1). The application of OMF as a biostimulant to soybean crops led to an increase in the first pod insertion height and the number of pods per plant; it did not lead to higher yields; however, when applied at phenological stage R5, higher yields were observed compared to application at R3