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AMOSTRAGEM EM CULTIVARES DE ALGODÃO COM FOCO EM TRIPES NO MUNICÍPIO DE NOVA MUTUM (MT)

2026-03-17T23:04:01Z

Título: AMOSTRAGEM EM CULTIVARES DE ALGODÃO COM FOCO EM TRIPES NO MUNICÍPIO DE NOVA MUTUM (MT) Autor(es): Santos, Anna Lydhia Souza Primeiro Orientador: Pereira, Alexandre Igor Azevedo Abstract: Insects of the order Thysanoptera are among the most relevant phytosanitary constraints in intensive agricultural systems, particularly during early plant development, when they may impair vegetative vigor and affect crop performance. This study aimed to characterize the population dynamics of these insects in 21 commercial genotypes grown under field conditions and contrasting phytosanitary management regimes, seeking to identify differences in genotype susceptibility, temporal variation in infestation, and the composition of the species community associated with the production system. Assessments were carried out at different times throughout the crop cycle, allowing population fluctuation to be examined in relation to crop development and management strategy. The results revealed marked variation in infestation among genotypes and sampling periods, confirming that the occurrence of these insects is strongly influenced by the interaction between plant genotype, developmental stage, and chemical intervention. In general, population increase was observed in plots without insecticide application, whereas treated plots showed oscillating responses across evaluation dates, indicating that chemical control efficiency was not uniform throughout the cycle. In addition, consistent contrasts were detected among materials regarding cumulative infestation, indicating different levels of favorability to insect establishment. The species community was largely dominated by Frankliniella brevicaulis and Frankliniella schultzei, with lower representation of Arorathrips mexicanus and Caliothrips phaseoli. Cluster analysis revealed that the most infested genotypes were associated with greater abundance of the dominant species. Taken together, these findings demonstrate that infestation arises from a multifactorial process and reinforce the importance of integrated strategies combining the selection of less susceptible genotypes, temporal monitoring, and species-level identification of the associated entomofauna to improve phytosanitary decision-making. Editor: Instituto Federal Goiano Tipo: Dissertação

APLICAÇÃO DE BIOLÓGICOS CONTRA TRIPES NO TOMATEIRO PARA PROCESSAMENTO INDUSTRIAL SOB DIFERENTES HORÁRIOS DE APLICAÇÃO, INCLUINDO A AVALIAÇÃO DE PROTETORES SOLARES

2026-03-12T23:30:23Z

Título: APLICAÇÃO DE BIOLÓGICOS CONTRA TRIPES NO TOMATEIRO PARA PROCESSAMENTO INDUSTRIAL SOB DIFERENTES HORÁRIOS DE APLICAÇÃO, INCLUINDO A AVALIAÇÃO DE PROTETORES SOLARES Autor(es): Cossio, Leidy Ximena Figueroa Primeiro Orientador: Pereira, Alexandre Igor Azevedo Abstract: Thrips (Thysanoptera) are a major phytosanitary constraint in tomato plants for processing fruits by the industry as raw material, requiring management strategies aligned with Integrated Pest Management (IPM) practices. This field study evaluated the efficacy of microbial bioinputs and operational spray factors for thrips management in processing tomato plants (cv. CVR 8161). The experiment followed a randomized complete block design in a 4×2×2+2 factorial scheme (four entomopathogenic bioinput agents, presence or absence of a UV-protective sunscreen additive in the spray solution with the bioinputs, and two application times (12:00 AM and 5:00 PM), plus two controls (water and the insecticide profenofos + cypermethrin), totaling 18 treatments. Three weekly foliar sprays were performed, and thrips populations were assessed nine times using the beat-tray method on apical shoots. Data were analyzed using linear mixed models, with the treatments as a random effect and fixed factors (days after application, products, UV protector, and application time). Thrips populations increased over time, highlighting the modulatory role of the UV protector and application time in reducing mean infestation levels and stabilizing residual effects. The best combinations included the UV protector, particularly at 12:00 AM, showing competitive performance and, in several scenarios, outperforming the chemical standard. The treatment Beauveria bassiana + Cordyceps javanica with UV protector at 12:00 AM yielded the lowest adjusted mean of thrips infestation, indicating higher relative efficacy under high pest pressure. Editor: Instituto Federal Goiano Tipo: Dissertação

SUBSTITUIÇÃO DO ACEFATO POR ISOXAZOLINA + PIRETRÓIDE EM UM MANEJO QUÍMICO ROTACIONADO CONTRA Dalbulus maidis, COM CONSEQUÊNCIAS FITOSSANITÁRIAS E PRODUTIVAS, PARA MILHO SAFRINHA

2026-03-12T17:32:30Z

Título: SUBSTITUIÇÃO DO ACEFATO POR ISOXAZOLINA + PIRETRÓIDE EM UM MANEJO QUÍMICO ROTACIONADO CONTRA Dalbulus maidis, COM CONSEQUÊNCIAS FITOSSANITÁRIAS E PRODUTIVAS, PARA MILHO SAFRINHA Autor(es): Silva, Frederico de Melo Primeiro Orientador: Pereira, Alexandre Igor Azevedo Abstract: The corn leafhopper, Dalbulus maidis (DeLong & Wolcott) (Hemiptera: Cicadellidae), the vector of the corn stunt disease complex, is among the principal constraints to maize production in Brazil, demanding integrated management programs that rotate insecticidal modes of action (MoA). However, experimental comparisons that explicitly connect spray programs to maize phenology while contrasting distinct MoA remain scarce. We evaluated, in the hybrid MG540 grown under rainfed second-season conditions, the agronomic relevance of two sequential foliar spray programs on vector populations, stunt incidence, and grain yield. The trial followed a randomized complete block design with three treatments (T). T1 was an absolute, water-only control. T2 comprised thiamethoxam + lambda-cyhalothrin at VE, three sequential applications of isocycloseram + lambda-cyhalothrin at 5-7 day intervals, one application of profenofos + cypermethrin, and two applications of acetamiprid + lambda-cyhalothrin (at 14-day intervals). T3 followed the same calendar as T2, but replaced isocycloseram + lambda-cyhalothrin with acephate in the three central sprays. Throughout vegetative development, we periodically monitored (per 1 m row) the number of leafhoppers per plant, the percentage of plants with leafhoppers, and the percentage of plants showing stunt symptoms. These metrics were paired with control efficacy (EC%) corrected by the Henderson–Tilton method. At the end of the phenological cycle, grain yield (sacks ha⁻¹; 60-kg sacks) was estimated for each treatment. Both time (spray calendar) and treatment effects were significant for all periodic parameters and their corresponding EC%. T2 sustained more stable suppression during the intermediate window, with a peak around 5-7 days after application of the fourth spray (5-7 DAA4), whereas T3 produced a stronger initial knock-down effect followed by mid-cycle instability. Stunt incidence emerged late, with the hierarchy T1 > T2 > T3, and higher early-outbreak efficacy under T2. For yield, T2 reached 161.19 ± 19.00 sacks ha⁻¹, T3 achieved 138.00 ± 18.00 sacks ha⁻¹, and T1 only 92.00 ± 22.00 sacks ha⁻¹. Overall, the application program embodied by T2 combined consistent vector suppression, mitigation of stunt expression, and high yield. Intensive monitoring from VE to V4, rotation of MoA with substitution toward newer insecticides, and reapplications scheduled between 5-7 days after the third to fifth applications (5-7 DAA3 and 5-7 DAA5) emerge as actionable findings to help growers manage high D. maidis pressure more decisively, protectively, and productively under field conditions. Editor: Instituto Federal Goiano Tipo: Dissertação

PLANO DE MANEJO COM INSETICIDAS E INDUTOR DE RESISTÊNCIA PARA O CONTROLE DE Dalbulus maidis E FITOPATÓGENOS ASSOCIADOS AO MILHO-DOCE

2026-03-06T21:08:30Z

Título: PLANO DE MANEJO COM INSETICIDAS E INDUTOR DE RESISTÊNCIA PARA O CONTROLE DE Dalbulus maidis E FITOPATÓGENOS ASSOCIADOS AO MILHO-DOCE Autor(es): Silva, Adriano de Almeida Primeiro Orientador: Pereira, Alexandre Igor Azevedo Abstract: The corn leafhopper Dalbulus maidis (Hemiptera: Cicadellidae) is the main vector of yield-limiting pathogens in sweet corn in Brazil. The use of new-generation insecticides combined with application frequency and different active ingredients, as well as plant defense inducers, is still an underutilized control strategy. These practices are aligned with Integrated Pest Management (IPM) and can reduce the negative impacts caused by maize rayado fino virus, one of the major pathogens in sweet corn transmitted by D. maidis in the state of Goiás, Brazil. This study evaluated the effectiveness of integrated crop-protection strategies involving the number of weekly applications of insecticidal products with different modes of action, with or without the resistance inducer acibenzolar-S-methyl (ASM), for controlling D. maidis and mitigating virus-related damage in the sweet corn hybrid GSS0227, as well as their effects on yield and industrial recovery under real field conditions. The experiment followed a randomized complete block design with eight treatments in a 3×2+2 factorial arrangement, comprising one, two, or three weekly insecticide application schedules, the absence or presence of ASM, and two controls (negative and positive). The assessed variables were the number of leafhoppers per plant, visual symptoms of maize rayado fino virus, yield (t ha⁻¹), and industrial recovery (%). Significant effects of application intensity and ASM, as well as their interaction, were observed for vector density and yield components. The negative control showed the highest infestation (>2.8 leafhoppers per plant), the highest symptom incidence (>50%), and the lowest yield (<18 t ha⁻¹) and industrial recovery (<35%). Insecticide-only programs provided partial control, reducing the population to 2.1–2.6 leafhoppers per plant and symptom incidence to 35–45%, with modest gains in yield (20–23 t ha⁻¹) and industrial recovery (38–43%). In contrast, adding ASM increased management efficiency, reducing infestation to 1.7–2.0 leafhoppers per plant and symptom incidence to 25–30%, while increasing yield (23–25 t ha⁻¹) and industrial recovery (44–48%). The best performance was achieved by the positive control program, which combined regular applications with systematic ASM use, reaching <1.6 leafhoppers per plant, ~22% symptomatic plants, yield >25 t ha⁻¹, and industrial recovery >48%. We conclude that integrating insecticide application intensity with the strategic use of ASM maximizes D. maidis control, reduces maize rayado fino expression, and simultaneously increases sweet corn yield and industrial recovery, representing a high-impact approach for IPM programs in regions under strong virus pressure. Editor: Instituto Federal Goiano Tipo: Dissertação