https://tede.unioeste.br/handle/tede/576 Thu, 06 Aug 2026 08:09:17 GMT 2026-08-06T08:09:17Z https://tede.unioeste.br/handle/tede/8591 Title: Controle biológico de Pratylenchus brachyurus em soja via tratamento de sementes Autor: Turatto, Nathalia Primeiro orientador: Costa, Antonio Carlos Torres da Abstract: Soybean (Glycine max L.) is the most widely produced grain in Brazil under extensive cultivation. However, its productivity can be impaired when pathogens, such as the root lesion nematode Pratylenchus brachyurus, are present in its root system. Due to the difficulty in controlling this pathogen, alternative methods have been studied, such as biological control using fungi and bacteria. The objective of this study was to evaluate the effect of biological products in the control of P. brachyurus in soybean. The seeds were treated with Bacillus firmus, Bacillus amyloliquefaciens, Trichoderma harzianum, Purpureocillium lilacinum and Pochonia chlamydosporia, in addition to the untreated control. In vitro experiments were performed to evaluate the mortality of P. brachyurus and in vivo experiments to evaluate the agronomic variables (root length, root volume, fresh root mass, dry mass of the aerial part) and nematological variables (number of nematodes in the root and in the soil). The latter was performed in two different growing seasons. All experiments had five replicates and followed the manufacturer's recommendations. In the in vivo assay, inoculation was performed at the time of sowing, with the inoculum consisting of 500 specimens of P. brachyurus per pot. The biological agents acted as nematicide in the in vitro experiment. In the in vivo assays, the results indicated significance of the treatments only for dry mass of the aerial part, number of nematodes in the soil and number of nematodes in the root. In the soil, the reduction ranged from 48% to 88%, while in the root, the reduction was between 49% and 84% in the number of nematodes. Thus, the tested products have potential for controlling P. brachyurus in soybeans via seed treatment. Publisher: Universidade Estadual do Oeste do Paraná Tipo do documento: Dissertação Thu, 27 Feb 2025 00:00:00 GMT https://tede.unioeste.br/handle/tede/8591 2025-02-27T00:00:00Z https://tede.unioeste.br/handle/tede/8585 Title: Manejo da ferrugem da folha (Puccinia coronata f. sp. avenae) na cultura da aveia (Avena sativa) com fungicidas microbiológicos e ácido silícico Autor: Matos, Sabrina dos Santos Primeiro orientador: Kuhn, Odair José Abstract: White oat is an important winter crop in Southern Brazil, and leaf rust, caused by Puccinia coronata f. sp. avenae, is its main disease, with the potential to cause yield losses of up to 50% in susceptible cultivars. This study aimed to evaluate the effect of microbiological fungicides and silicic acid on the management of leaf rust and on yield components of white oat. Two field experiments were conducted using the cultivar IPR Artemis. The experimental design was a randomized complete block design in a split-plot arrangement, with the presence or absence of silicic acid as the main factor and five microbiological fungicides plus a control as the secondary factor. The variables evaluated were disease severity, area under the disease progress curve, plant height, stem diameter, number of tillers, number of panicles, number of spikelets in the main panicle, thousand-grain weight, and grain yield. Silicic acid application reduced leaf rust severity by 14%. Trichodermil® and Bio-imune® reduced disease severity by 20.8% and 20.3%, respectively, compared with the control, while the association of Pardella® with silicic acid reduced the area under the disease progress curve by 17.5%. The association of Trichodermil® with silicic acid increased thousand-grain weight by 21%, although it reduced plant height and the number of spikelets in the main panicle. The use of Trichodermil® also reduced stem diameter. Grain yield was not affected by the evaluated treatments. It was concluded that silicic acid and microbiological fungicides have potential for the management of white oat leaf rust; however, they did not promote increases in grain yield under the conditions of this study. Publisher: Universidade Estadual do Oeste do Paraná Tipo do documento: Dissertação Fri, 28 Feb 2025 00:00:00 GMT https://tede.unioeste.br/handle/tede/8585 2025-02-28T00:00:00Z https://tede.unioeste.br/handle/tede/8507 Title: Desenvolvimento radicular e da parte aérea de estacas de goiabeira, com utilização de bioestimulantes comerciais e ácido indolbutírico Autor: Veiga, Joice Ferreira da Primeiro orientador: Villa, Fabíola Abstract: Vegetative propagation by cuttings is widely used in the production of guava seedlings (Psidium guajava L.); however, it presents physiological limitations related to rooting and the initial development of cuttings. Therefore, the objective of this study was to evaluate the root and shoot development of cuttings from four guava cultivars using commercial biostimulant products associated with indolebutyric acid (IBA). Two experiments were conducted between February and March 2025, in the seedling nursery of the State University of Western Paraná (Unioeste). Experiment I was conducted in a randomized block design, in a 4 × 4 factorial scheme (4 cultivars: Tailandesa, Paluma, Século 21 and Pedro Sato × 4 rooting treatments (IBA, IBA + ComposFix®, IBA + BioRaiz® and IBA + humic acid), with three replications and 20 cuttings per plot. For experiment II, the same design applied in the first experiment was used, in a 2 × 4 factorial scheme (2 Bacillus types × 4 product concentrations: 0, 50, 75 and 100 mL), with three replications, each replication composed of 15 cuttings, totaling 360 cuttings. The cuttings in both experiments were treated with IBA in a hydroalcoholic solution at 6,000 mg L⁻¹, by quick immersion of the base, and conducted in seedbeds containing washed sand under a protected environment. After 70 days, the percentage of rooted cuttings, number of roots, length of the longest root, number of calluses, number of shoots, shoot length, shoot diameter, and number of leaves were evaluated. The percentage of rooted cuttings did not differ statistically among treatments, although the observed values were satisfactory. It is concluded that biostimulants associated with IBA mainly influence the initial vegetative growth of cuttings, while IBA favors the development of the root system of the cultivar Paluma. The use of biological products associated with indolebutyric acid influenced the initial development of guava cuttings cv. Tailandesa, with responses dependent on the microorganism, with Bacillus subtilis standing out in the early stages of rooting. Publisher: Universidade Estadual do Oeste do Paraná Tipo do documento: Dissertação Fri, 20 Feb 2026 00:00:00 GMT https://tede.unioeste.br/handle/tede/8507 2026-02-20T00:00:00Z 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 Thu, 26 Feb 2026 00:00:00 GMT https://tede.unioeste.br/handle/tede/8476 2026-02-26T00:00:00Z