https://tede.unioeste.br/handle/tede/576 2026-06-29T10:58:01Z https://tede.unioeste.br/handle/tede/8476 Title: Correlação entre enzimas microbianas no solo e comunidade de nematoides em sistemas de plantio direto orgânico Autor: Maquivatihe, Nordino Francisco Primeiro orientador: Stangarlin, José Renato Abstract: The sustainability of organic agricultural systems is intrinsically linked to soil biological quality. This study aimed to relate the structure of free-living nematode communities with the activity of microbial enzymes (β-glucosidase, acid phosphatase, and arylsulfatase) in a no-till organic system under seven different crop rotations, seeking to identify integrated indicators of soil quality. Twenty composite soil samples (0-10 cm) were collected in an experimental area. Nematodes were quantified and identified, ecological indices (diversity, maturity, trophic ratios) were calculated, and the activity of the three enzymes was determined. Data were subjected to descriptive statistics, correlation analysis, geostatistics (kriging), principal component analysis (PCA), and clustering. Results revealed high spatial variability in nematode abundance, with dominance of bacterivore groups (56.5%) and a decreasing gradient of diversity and maturity among plots. Enzymatic activities showed independent spatial patterns, with higher values associated with more diversified rotations. PCA and cluster analysis successfully integrated both datasets, identifying five distinct ecological profiles that combine specific nematode signatures with enzymatic activities. Kriging of the principal components allowed the spatial visualization of these patterns. In conclusion, the nematode community and enzymatic activity are sensitive and complementary bioindicators. Their integrated assessment provides a robust tool for diagnosing soil health and biological quality in sustainable agricultural systems, being strongly influenced by the diversification of crop rotations. Publisher: Universidade Estadual do Oeste do Paraná Tipo do documento: Dissertação 2026-02-26T00:00:00Z https://tede.unioeste.br/handle/tede/8433 Title: Bioprospecção de bactérias promotoras de crescimento vegetal e controle biológico de Fusarium sp. na região sul do Brasil Autor: Panzitta, Mercedes Belen Primeiro orientador: Guimaraes, Vandeir Francisco Abstract: Plants and bacteria coevolve and continuously interact, establishing symbiotic relationships that enhance nutrient uptake and plant protection through the activity of beneficial microorganisms, such as plant growth–promoting rhizobacteria (PGPR). These bacteria produce bioactive compounds that increase plant tolerance to stress and promote plant growth through both direct and indirect mechanisms, including pathogen suppression. Such characteristics enable the development of biofertilizers and biopesticides as sustainable alternatives to conventional chemical inputs. Within this context, this study evaluates the potential of plant growth– promoting bacteria as multifunctional bioinputs by investigating their ability to solubilize phosphorus and potassium, produce indole-3-acetic acid (IAA), and exert biological control against Fusarium sp. in Southern Brazil. The research also identifies the predominant bacterial genera and species using mass spectrometry techniques and bioprospecting approaches, in addition to characterizing metabolic profiles associated with plant growth promotion. The results demonstrate a high potential of isolates belonging to the genera Bacillus and Paenibacillus, as well as promising performance of less explored species from the genera Microbacterium and Nocardioides. These findings highlight the importance of soil microorganism bioprospecting for the development of innovative and sustainable agricultural bioinputs. Publisher: Universidade Estadual do Oeste do Paraná Tipo do documento: Dissertação 2026-02-24T00:00:00Z https://tede.unioeste.br/handle/tede/8428 Title: Características agronômicas de cinco cultivares de soja em quatro densidades populacionais de plantas Autor: Muniz, Paulo Vitor Dallacort Primeiro orientador: Duarte Júnior, José Barbosa Abstract: Soybean is a globally important crop and the main oilseed cultivated worldwide, particularly in Brazil. This study aimed to evaluate the effects of different plant densities on the agronomic traits of soybean cultivars, as well as their performance under distinct population arrangements. The following agronomic traits were quantified: plant height, number of pods per plant, thousand-grain weight, and grain yield. The experiment was conducted in a randomized complete block design with four replications, arranged in a 5 × 4 factorial scheme, consisting of five cultivars (NEO 590 I2X, DM 5961 I2X, CZ 15B99 I2X, CZ 16B12 I2X, and ST 616 I2X) and four plant densities (180,000; 240,000; 280,000; and 320,000 plants ha⁻¹). The cultivars showed different responses to plant density variation. Plant height increased with higher densities, associated with greater intraspecific competition for light. The number of pods per plant and thousand-grain weight tended to decrease at higher populations, indicating assimilate limitation per plant. Grain yield showed a non-linear response, with maximum values generally observed at intermediate densities, suggesting compensation between individual plant components and plant number per area. Responses varied among cultivars, resulting in a significant cultivar × density interaction. Moderate plant densities promoted a better balance between vegetative and reproductive growth, highlighting the need for cultivarspecific population recommendations to maximize yield performance. Publisher: Universidade Estadual do Oeste do Paraná Tipo do documento: Dissertação 2026-02-19T00:00:00Z https://tede.unioeste.br/handle/tede/8427 Title: Polissacarídeos de Pycnoporus sanguineus para indução de resistência em tomateiro contra Meloidogyne javanica Autor: Carmo, Rafaela Moreira do Primeiro orientador: Stangarlin, José Renato Abstract: Plant-parasitic nematodes, such as Meloidogyne spp., have limited tomato crop productivity. Some studies suggest the use of basidiomycete fungi, such as Pycnoporus sanguineus, as an alternative for nematode management. Thus, this study aimed to evaluate the potential of P. sanguineus polysaccharides (PPS) in inducing resistance in tomato plants against M. javanica. The study was conducted in three trials. In the initial trial, the most effective concentration for nematode control was determined, using six PPS concentrations (0, 100, 200, 300, 400, and 500 mg L⁻¹), and evaluating the number of galls and egg mass, egg viability, number of eggs and second-stage juveniles (J2) in the soil and roots, and the reproduction factor. With the PPS concentration established in the first trial, the second trial aimed to determine the best method of PPS application. Based on the results of the first and second experiments, the third experiment used only the treatments most effective in controlling nematodes and examined the defense mechanisms involved in the induction of resistance: total phenolic compound content, the production of reactive oxygen species such as hydrogen peroxide (H₂O₂) and the superoxide anion (O₂⁻), and the activity of the enzymes phenylalanine ammonia-lyase, polyphenol oxidase, peroxidase, ascorbate peroxidase, catalase, and superoxide dismutase. These latter assessments were conducted based on root sample collection at different time points following PPS application (zero (day of treatment), 3 (day of inoculation), 7, 11, 15, 19, and 23 days). The concentration with the highest control level was 500 mg L⁻¹, with reductions of up to 70% in eggs+J2 in the roots. Regarding application methods, the greatest control of nematodes occurred through spraying PPS on the aboveground parts of the plants, with reductions of 66% in eggs+J2 in the soil. Histological and biochemical analyses revealed increased cell wall thickness, which was linked to higher deposition of phenolic compounds and lignin, along with increases in polyphenol oxidase activity, indicating an induced defense response that acted primarily on the maintenance of nematode feeding sites. It is concluded that polysaccharides from P. sanguineus act as resistance inducers in tomato plants, reducing populations of the nematode M. javanica. Publisher: Universidade Estadual do Oeste do Paraná Tipo do documento: Dissertação 2026-02-12T00:00:00Z