Revista Verde de Agroecologia e Desenvolvimento Sustentável

Feasibility study of organic fishing in a family production unit in Laranjeiras do Sul, Parana, Brazil

Vera Maria Rossignol — 2024-05-15

The role of family farming has been gaining strength, driven by debates based on sustainable rural development, the generation of work and income, contributing to food security. Organic fish farming is an activity that can be developed by these farmers to promote sustainability. From this perspective, the objective of this work is to analyze the economic/financial, environmental and social viability of fish production in an organic system in excavated ponds based on a case study. The methodology adopted to achieve the objectives has an exploratory and descriptive character, combining bibliographical research on studies analyzing organic production in general and fish farming with case studies. Over a period of sixteen months, the production of organic fish in a polyculture system was monitored, using natural foods from the property. In the analyses, economic viability analysis techniques were used: Net Present Value (NPV); Discounted Payback (PB); Internal Rate of Return (IRR); and Profitability Index (IL). The amount invested in the nurseries was R$3,220.60. The estimated value for selling the fish was R$2,477.50. In the economic/financial viability analysis, the results indicate a return from the second production cycle. In the social dimension, occupied family labor stands out and whose greatest demand is during the implementation period, while this need is low in maintenance. In the environmental analysis, the results indicated the preservation of natural resources, with the reuse of food waste produced on the property and care with water and the generation of effluents.

Reference Specifications: A study on biological control in brazilian organic agriculture

Jeremias Marques de Sousa — 2024-05-15

Organic production has an important challenge in the supply of inputs. Bio-inputs for biological control, through reference specifications, are presented as promising solutions. Therefore, this article analyzes the participation of bioinputs for biological control in Brazilian organic agriculture. To this end, it characterized the scenario of organic agriculture and biological control and then carried out, in two stages of research, an analysis of the opinions of experts in organic production. The results were positioned in the expansion of organic production and market, as well as biological control, both activities permeated by public policies. They also pointed out bioinputs as technologies that are little known and little used by organic producers, mainly small and medium-sized ones, a situation also observed for the instruments provided for in the reference specifications. Finally, the results indicated that overcoming this scenario lies in the integration between the policies being implemented, social movements and business actions, associated with the promotion of research and rural extension.

Lettuce production under the effect of cow urine application in a protected environment

Nielva Juliana Cezar dos Santos — 2024-05-15

Lettuce is a leafy vegetable traditionally cultivated by family farmers who employ sustainable techniques in their cultivation, such as the use of alternative solutions for fertilization, seeking resources available on the properties, such as cow urine in nitrogen fertilization. The use of materials is fundamental to promote the sustainability of agriculture and the conservation of the environment, reducing nutrient losses and optimizing their use. The cultivation of plants in greenhouses can provide an increase in their production and productivity, in view of the environment better controlling climatic factors. In view of the above, the present work aimed to evaluate the productive performance of the (Maravilha, Romana, Romana white, Regina and Regina de Verão) lettuce varieties, submitted to the application of cow urine via soil in a protected environment. The variables number of leaves (NF), plant height (AP), average diameter (DM); shoot green mass, shoot dry mass, root green mass and root dry mass. Cow urine provided better results for all demonstrated varieties, with Regina having the best performance for NF and DM and the white Romana variety having the best results for the other variables. Cow urine, as a natural fertilizer, applied via soil, is an alternative to increase the development and growth of lettuce.

Morphogenesis of grazing sorghum hybrids as a function of row spacing

Thiago Martins dos Santos — 2024-05-15

The planting of sorghum hybrids for grazing is an alternative for forage production in the state of Tocantins. The objective of this work was to evaluate the morphogenesis characteristics of sorghum hybrids for grazing and to identify the plant density that promotes better yield. The experimental design was in complete randomized blocks, in a 2 x 4 factorial arrangement, with four replications, totaling 32 experimental units. The first factor represented two sorghum hybrids (BRS 800 and CMSXS 766), while the second factor included four row spacing levels (15, 30, 45 and 60 cm). The variables analyzed were green forage accumulation, leaf elongation rate, stem elongation rate, number of live leaves per tiller, leaf appearance rate, length end of leaves and phyllochron. At the end of the study, it was observed that the sorghum hybrid for grazing CMSXS 766 used in the spacing of 15 cm between rows (800,000 thousand plants per hectare) is the most suitable to achieve higher productivity under the imposed conditions. The sorghum hybrids BRS 800 and CMSXS 766 are viable in the State of Tocantins and can be used up to the third regrowth.

Vegetative growth of Coffea arabica L. seedlings inoculated with Trichoderma harzianum and Beauveria bassiana

Ricardo Arizono dos Reis — 2024-05-15

Growth promoting fungi have the potential to be used in seedling production. The objective of this work was to evaluate the vegetative growth of Coffea arabica L. seedlings inoculated with the fungi Trichoderma harzianum and Beauveria bassiana, and to determine the immersion time of the seeds in the conidia suspension. The seeds were immersed in the conidia suspension (1 x 10⁷ conidia.mL^-1) for 0h, 6h, 12h, 24h, 48h and 96h, constituting a 3 x 6 factorial arrangement in randomized blocks. The following were evaluated: aerial part height, collar diameter, number of pairs of leaves, leaf area, root length, fresh and dry mass. The fungus B. bassiana promoted greater plant height at times 0h, 6h and 96h and a greater number of pairs of leaves at times 6h and 96h. The fungus T. harzianum promoted shorter root length and the fungus B. bassiana at 6h and 96h. The fungus T. harzianum promoted greater diameter of the seedling neck at 12h, 48h and 96h. The fungus B. bassiana promoted greater fresh mass of aerial parts compared to the fungus T. harzianum. There was no significant difference between the other parameters. The 65h seed immersion time promoted greater leaf area and there is no relationship with growth promoting fungi. Research with the fungi B. bassiana and T. harzianum should be expanded, since there is evidence of gains in certain vegetative growth parameters, such as plant height and stem diameter. The immersion time is not a determining factor in the vegetative growth of Arabica coffee seedlings, in the presence of the fungi B. bassiana and T. harzianum.

Lead and cadmium content in soil, oil palm fiber, and palm kernel in the oil palm plantation with mulch application

Syifa Divanda Winarko — 2024-05-15

Solid waste in palm oil mills is waste that has the potential to have a negative impact on the environment if not used properly. One of the solid wastes from palm oil mills is empty fruit bunche (EFB) which can be used as mulch on oil palm land. The mulch and inorganic fertilizer used can contain heavy metals, such as Pb and Cd. This study was aimed to assess the heavy metal content of Pb and Cd in the soil, fibers and kernels of oil palm fruit. This study evaluated the Pb and Cd content in the soil at depths of 0 – 20 cm and 20 – 40 cm, palm fiber and palm kernel. The results showed of the study showed that the Pb and Cd content of soil on land applied with inorganic fertilizer was greater than the Pb and Cd content of soil on land applied with mulch, where on land applied with mulch the level of Pb contamination was in the very slightly contaminated category, while Cd was in the quite polluted category, and inorganic fertilizer land is heavily polluted. On land where mulch was applied, the Pb and Cd content of fiber and kernel was smaller than the Pb and Cd content of fiber and kernel on land where inorganic fertilizer was applied.

Edaphic recovery of degraded soils with combined use of leucaena (Leucaena leucocephala) and vetiver grass (Chrysopogon zizanioides) in Vandúzi, Mozambique

Domingos Tomás — 2024-05-15

Soil recovery is a process aimed at reversing its degradability by incorporating favorable conditions (physical, chemical, and biological) to restructure life so that, through intervention, it can regenerate. This study aimed to analyze the potential combined use of leucaena (Leucaena leucocephala) and vetiver grass (Chrysopogon zizanioides) for the recovery of degraded soils in the Nhamurenguera area, Vandúzi District, Mozambique. The experimental method included soil study (physical-chemical analyses), area preparation (field and seedbed), field management, topographic survey, and qualitative and quantitative visual assessment of the developing seedlings. A total of 650 leucaena and 680 vetiver grass seedlings were planted in an area of 0.5 ha, with a spacing of 4 m between rows and 2 m between seedlings of both species in consort. Three months after planting, the survival and adaptability levels of the seedlings were evaluated. The results showed that 17% of the leucaena individuals and 12% of the vetiver grass died due to ant attacks and insufficient moisture, despite the use of mulching. Regarding the seedlings' reaction to soil conditions, 94% of leucaena and 79% of vetiver showed slow development in the first 3 months of planting due to soil compaction and low nutrient availability (leaching). After four years, soil chemical parameters were evaluated and compared with pre-leucaena/vetiver consortium soil data. The pH values, electrical conductivity, NPK contents, calcium, and magnesium increased, improving soil quality and indicating a soil recovery process to prepare it for subsequent agricultural use, especially for cereal and legume crops.

Use of alternative rooting agents in fruit tree cuttings

Gabriel Batista Dantas — 2024-05-15

The objective of this work was to realize a literature review on the use of alternative rooting agents in rhizogenesis stimulating on fruit trees, analyzing the methods used and their effectiveness, under the hypothesis that alternative rooting agents promote effective rhizogenesis on fruit trees of commercial interest, both as commercial rooters. For this, Google Scholar was used as a search platform, using the first 10 tabs, in each of the search descriptors. A total of 426 scientific works and papers were found, and 263 were used, according to the selection criteria applied. Of these, 166 were in Portuguese and 97 in English; 228 dealt with conventional rooters, and 35 with alternative rooters. 53% of the total published works dealt with fruit trees, however, only 11% used alternative rooting agents. The most used alternative rooting agent was the aqueous extract of Cyperus rotundus L. (Cyperaceae), and the most used phytohormone was Indolebutyric Acid (IBA), for comparison with the treatments. In general, the alternative rooters presented satisfactory results or even better than the other treatments used, which demonstrates the viability of using them in rooting cuttings.

Urban garden initiatives in small spaces

Ramôn da Silva Santos — 2024-05-15

Human health is intrinsically linked to the consumption of quality food from reliable and safe sources. Although large-scale production often relies on conventional methods, the growing demand for healthy foods, driven by the agroecological movement, emphasizes the importance of healthier alternatives. Urban gardening in limited spaces has become popular, ensuring the origin of food and promoting social well-being. However, it is important to improve these systems to guarantee quality and proper management of space, water, and soil. This study aims to investigate urban cultivation initiatives based on agroecological principles that positively impact sustainability, health, and food security. The literature review used the Web of Science platform with the following search parameters: (("Urban Agriculture") AND ("Cultivation in urban environments")) from 2013 to 2023. The last four years have shown a significant increase in publications on the topic. Areas such as Agronomy, Environmental Sciences, Plant Sciences, Sustainable Technology, and Environmental Studies addressed the adoption of urban cultivation techniques. There is a growing trend in Urban Studies, positively influencing mental and emotional health by reducing urban life stress. The implementation of these techniques offers a healthy food source, contributes to a more economical life, and promotes sustainability.