https://repositorio.ufpb.br/jspui/handle/tede/3744 2026-08-10T14:55:22Z https://repositorio.ufpb.br/jspui/handle/123456789/38589 Título: Dinâmica populacional, abundância e potencial de infestação de Zaprionus tuberculatus e Zaprionus indianus (Diptera: Drosophilidae) Autor(es): Carmo, Ellen Vitoria Barbosa do Orientador: Brito, Carlos Henrique de Abstract: Brazil holds a prominent global position in fruit production due to its favorable soil and climatic conditions and technological development, factors that drive production across all regions. However, tropical fruit production faces serious challenges related to the incidence of invasive drosophilids, among which fruit flies (Diptera: Drosophilidae) constitute one of the main production and commercial constraints. Among these species, Zaprionus tuberculatus and Zaprionus indianus stand out for their high adaptability, short life cycle, and high biotic potential—traits that favor their dispersal in tropical environments and intensify their impacts on orchards. In this context, the present study aimed to evaluate the population dynamics, population fluctuation, abundance, and infestation potential of Z. indianus and Z. tuberculatus in home orchards in the Agreste mesoregion of Paraíba, considering attractants and sampling methods, stratum of occurrence, available hosts, infestation indices, climatic variation, and differences among municipalities. To this end, factors such as food attractants, stratum of occurrence, sampling methods, available hosts, climatic variation, and differences among municipalities were assessed. The research was conducted from May 2024 to April 2025 in five municipalities, using McPhail traps with different attractants and collecting host fruits for faunistic analysis and infestation indices. Data were analyzed using Generalized Linear Mixed Models (GLMMs) with a negative binomial distribution. The results show that guava juice is more efficient for capturing Z. tuberculatus, whereas Z. indianus shows no clear preference. Z. indianus is more abundant in fruits fallen on the ground, while Z. tuberculatus predominates in the plant stratum. Traps are more effective than fruit collection for continuous monitoring. Diversity indices vary among municipalities, and guava is identified as the preferred host for both species. The municipalities of Remígio and Pilões show the highest abundances of Z. indianus and Z. tuberculatus. Relative humidity shows a positive trend but no statistical significance for the abundance of Z. indianus and Z. tuberculatus. Mean temperature has a significant effect of low magnitude. Precipitation shows no significant association. Species-specific analyses did not reveal significant interactions with environmental variables. We recommend intensifying monitoring at the beginning and end of the rainy season, when population peaks become more evident, and expanding studies over broader temporal and spatial scales to support more effective and sustainable control strategies. Editor: Universidade Federal da Paraíba Tipo: Dissertação 2025-11-07T00:00:00Z https://repositorio.ufpb.br/jspui/handle/123456789/38588 Título: Melatonina, serotonina e dopamina na mitigação do estresse hídrico em beterraba Autor(es): Silva, Rodrigo Ribeiro da Orientador: Batista, Diego Silva Abstract: Modern agriculture faces significant challenges due to the impacts of climate change, especially during extreme weather events. Prolonged droughts have negatively affected crop productivity, leading to morphological and biochemical adaptations that can compromise plant performance. In this context, the use of bioregulators such as melatonin, serotonin, and dopamine emerges as a promising alternative. This potential is based on their roles as antioxidants and plant growth regulators, offering strategies to enhance plant resilience under adverse climatic conditions. This study aimed to evaluate the influence of melatonin, dopamine, and serotonin application on the morphophysiology and postharvest quality of beetroots grown under water deficit conditions. Beet plants were cultivated in pots filled with commercial substrate and subjected to treatments combining two irrigation regimes—well-watered (80% of substrate water-holding capacity) and water deficit (30% of capacity)—and foliar applications of distilled water (control), melatonin and dopamine at 100 mM, and serotonin at 5 mM. Morphological, physiological, and postharvest variables were assessed throughout the experiment. Biomass, morphology, and photosynthetic capacity were reduced by water deficit, and the bioregulators did not mitigate the damage caused by drought for most of the evaluated variables. However, serotonin promoted greater carbon assimilation under drought compared to full irrigation. In drought-stressed plants, dopamine reduced electrolyte leakage compared to untreated plants and increased root sugar content, indicating improved oxidative balance. Water deficit reduced vitamin C content in control roots, whereas no significant differences were observed in bioregulator-treated plants across irrigation conditions. Melatonin showed a stronger effect under well-watered conditions, improving carbon assimilation, photosynthesis, phenolic synthesis, and antioxidant activity, while maintaining soluble solids levels under stress, suggesting an osmoprotective action that reduces the need for osmolyte accumulation. Bioregulator-treated plants preserved skin coloration under drought, enhancing visual quality. These results demonstrate that severe stress greatly affected beet production and quality. Although bioregulators did not reverse most of the effects of water deficit, they influenced plant physiological traits under stress, particularly dopamine and serotonin. Further research is needed to understand how these compounds affect plant physiology under moderate stress and to determine appropriate application concentrations, given their activity at low doses in plants. Editor: Universidade Federal da Paraíba Tipo: Dissertação 2025-06-17T00:00:00Z https://repositorio.ufpb.br/jspui/handle/123456789/38587 Título: Abordagens uni e multidimensionais para compreensão da dinâmica de infestação de Diatraea impersonatella em variedades de cana-de-açúcar em sistemas irrigado e sequeiro Autor(es): Silva, Roberto Balbino da Orientador: Malaquias, José Bruno Abstract: Sugarcane is highly relevant for neotropical agribusiness, with Brazil being the world's largest producer and exporter of sugar. However, crop productivity and quality are threatened by infestation of lepidoborers of the Diatraea complex, such as the species Diatraea impersonatella (Walker, 1863) (Lepidoptera: Crambidae), which causes significant losses in the sugarcane agroindustry. Therefore, this study aimed to evaluate, from both univariate and multivariate perspectives, whether the dynamics of D. impersonatella infestation are influenced by sugarcane varieties, plant age, cultivation conditions, and distance from the carrier. For this purpose, the insect infestation levels were analyzed in the following varieties: RB 92-579, RB 04-1443 and RB 86-7515, at ages of 45, 70, 130 and 200 days after planting, in two conditions of dry and irrigated planting and distance from the carrier of 0, 10, 30 and 90 meters. The research was conducted in five municipalities in the state of Paraíba, where the number of bored stalks per plot and agro-industrial variables were quantified. Plants aged 45 days were evaluated based on the observation of wilting symptoms on the main leaf (dead heart) and subsequently subjected to opening to detect the pest. Plants aged 70, 130, and 200 days were subjected to straw removal and checked for the presence of borer entry holes. Based on the results obtained, it was observed that all varieties tested were infested by the borer, with the RB 92-579 variety showing greater susceptibility. A positive unidirectional relationship was observed involving the incidence of attack with the age of the plant, where the incidence of D. impersonatella was already observed from 45 days after planting. Among the cultivation systems, a greater infestation was observed in the irrigated system, a fact validated by the adopted multidimensional scaling. For the distance from the carrier, it was observed that the presence of the pest increased with proximity to the carrier. The univariate and multivariate findings revealed bioecological information fundamental for the management of D. impersonatella, indicating that control measures should consider the age of the plants, the cultivated variety, the cultivation system, and the distance from the carrier. Editor: Universidade Federal da Paraíba Tipo: Tese 2025-02-21T00:00:00Z https://repositorio.ufpb.br/jspui/handle/123456789/38586 Título: Opções de Manejo com Produtos com Diferentes Mecanismos de Ação e Indução de Resistência para Diaspis echinocacti Bouché em Opuntia stricta Haw Autor(es): Cartaxo, Paulo Henrique de Almeida Orientador: Malaquias, José Bruno Abstract: Forage cactus (Opuntia stricta Haw.) has established itself as one of the main food sources for livestock in the Brazilian semiarid region, especially during dry periods. However, the intensification of cultivation has favored the increase of pests, such as the scale insect (Diaspis echinocacti Bouché), which compromises plant development and productivity. Therefore, the objective of this study was to evaluate whether insecticides with different mechanisms of action and the application of potassium silicate reduce pest infestation and increase crop agronomic performance. In the first experiment, first-instar mobile nymphs were topically exposed to four insecticides (Acetamiprid + Fenpropathrin, Spinetoram, Azadirachtin and Teflubenzuron), in five concentrations each, with mortality assessments at 0, 24, 48, 72, 96 and 120 hours. The mixture of Acetamiprid + Fenpropathrin was the most efficient, with 98% mortality at the highest concentration (4000 ppm), median lethal concentration CL₅₀ of 1530 ppm and median lethal time (LT₅₀) of 48 h. Spinetoram showed 95% mortality and CL₅₀ of 1590 ppm, with a lethal time of 24 h. Azadirachtin reached 88% mortality only at the dose of 32000 ppm, with a longer action. Teflubenzuron was the least efficient, with a lethal time of 72 h. In the second experiment, the influence of potassium silicate doses and application times on scale infestation and palm productivity was evaluated using a supervised machine learning model (Decision Trees) applied at four different times, in addition to a control treatment. The 28 mL L⁻¹ dose provided the best results, with a significant increase in productivity and reduction in infestation, indicating a resistance-inducing effect. The results demonstrate that the integrated use of chemical and nutritional strategies can be highly efficient in the management of scale insects and in increasing the productivity of forage cactus, contributing to more sustainable production systems in the Brazilian semiarid region. Editor: Universidade Federal da Paraíba Tipo: Tese 2025-05-29T00:00:00Z