Sowing occurs in agricultural areas with irregular relief, influencing the quality of seed and fertilizer distribution. The aim of this study was to analyze the performance of different fertilizer metering mechanisms of planters as a function of longitudinal inclination. The experimental design was a completely randomized design with five treatments and six replications. Treatments consisted of five longitudinal inclinations to the metering mechanism (−10, −5, 0, 5, and 10 degrees). The mass of fertilizer collected per minute was considered as a replication. We worked with two types of fertilizers: a mixture of granules and powder. Metering mechanisms used were a horizontal toothed rotor, helical without flow restrictor, helical with lateral overflow, and helical with longitudinal overflow. The longitudinal inclination of ±10° in relation to the leveling altered the metered amount of both fertilizers used in all metering mechanisms. The helical with lateral overflow was the metering mechanism that obtained the smallest amount variation of fertilizer distributed in the different longitudinal inclinations, followed by the helical with longitudinal overflow, horizontal toothed rotor, and helical without flow restrictor.
Smallholders constitute more than three quarters of the world’s farmers, and despite their numbers, they commonly lack opportunities to advance their development status. Bioenergy production and consumption can help sustain smallholders’ energy needs and generate employment and income, but it also raises concerns over social justice and equity, especially where crops used for bioenergy could also be used for food. This perspective paper is grounded in a literature review related to three different crops in Brazil: sugarcane, landrace maize and sweet potato. It seeks to determine if these crops offer the potential to support smallholder farmers’ development in a more equitable way, focusing on opportunities for their use in bioenergy. We review the literature to identify policies shaping the smallholder development context in relation to these crops, assessing whose knowledge informs policy and institutional decision making, and highlighting the policy attention afforded to the different crops from different sectors. We further evaluate the literature on each crop in relation to water use and calorific value (i.e., food and energy). Our review indicates that while sugarcane has received the most policy and institutional attention, its development is largely anchored in research and development investments that support large-scale commercial farms and agri-businesses. Smallholders have not benefited or had the opportunity to engage in relevant policy decision making for sugarcane cultivation. At the same time, smallholders hold valuable untapped knowledge on the cultivation of sweet potato and landrace maize, both of which have the potential to generate development opportunities for smallholders. Our review suggests that the environmental impact of landrace maize and sweet potato in terms of water use is significantly lower than sugarcane, while they can generate more calories for energy or food consumption and offer diversification opportunities. Despite that these alternative crops offer considerable untapped potential to support rural development, more research is still needed to harness these benefits. Changes are needed to address inequities in policies, institutions and the types of knowledge informing decision making. Such changes need to afford smallholder farmers greater recognition and participation in decision making, so that the distribution of benefits from the three study crops can reach them to support their development better.
HighlightChanges in 3D anisotropy across the soybean axis during seed germination revealed a radicle-biased pattern of cell growth and position-specific changes in cell anisotropy.
R E S U M OCom a crescente demanda por óleos para a produção de biocombustíveis, espécies que apresentem elevado conteúdo de óleo, como o pinhão-manso (Jatropha curcas L.), são alternativas importantes, frente às opções tradicionais. Tendo em vista que o florescimento se distribui ao longo do ciclo de desenvolvimento da cultura do pinhão-manso objetivou-se, com este trabalho, determinar a época de colheita em dias após o florescimento, adequada para maximização do rendimento de óleo e da qualidade fisiológica de sementes. Physiological quality and total lipids of physic nut seeds (Jatropha curcas L.) according to harvest time A B S T R A C TWith the increasing demand for oils for biofuel production, species with high oil content, like physic nut (Jatropha curcas L.), are important alternatives in the face of traditional options. Considering that flowering is distributed throughout the development cycle of physic nut crop, the aim of this work was to determine the harvest time, in days after flowering, appropriate to maximize oil yield and physiological quality of seed. In two growing seasons, 2010/2011 (Year 1) and 2011/2012 (Year 2), at Paranavaí in the State of Paraná. Physic nut fruits were harvested at five times, determined by days after flowering: 30, 45, 60, 75 e 90. In completely randomized design, in a split-plot design the water content, dry matter, total lipids, seedling emergence in sand and speed of emergence-index were determined. By the behavior of the variables, harvests should be performed from seventyfive days after flowering. Palavras-chave:maturidade fisiológica teor de lipídios germinação biocombustíveis
The objective of this experiment was to compare employment contract systems based of hourly pay and payment for piecework in relation to the main activities performed in an ornamental plants production company. The experimental design was completely randomized, with four treatments and five repetitions. The treatments consisted of hourly payment in the first year and piecework in the following three years. The analyzed variables were the results regarding the numbers of containers (trays/pots) h -1 and the employee's payment in US$ h -1 ; the movement of containers; the spacing of plant containers; the removal of flowers/leaves; and pruning. Both the number of processed containers and the remuneration significantly increased for all the evaluated activities when the company started to use pay staff based on productivity.
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