Empresa de Pesquisa Agropecuária e Extensão Rural de Santa Catarina

Abstract This study evaluated the effects of dietary supplementation with ALLPRO, a source of docosahexaenoic acid (DHA—C22:6n‐3, 126 g kg −1 dry weight) and nucleotides (5 g kg −1 dry weight), on Nile tilapia farmed in southern Brazil during autumn, winter, and spring. Two isoenergetic diets were tested: one supplemented with 1.7 g ALLPRO 100 g −1 of diet (dry weight), based on prior studies performed under lab conditions, and a control diet without n‐3 polyunsaturated fatty acids (PUFAs). Juvenile tilapia (16.09 ± 0.13 g) were stocked at 45 fish m −3 in 12 net cages (1.6 m 3 ) placed in a pond. A completely randomized design with six replicates per treatment was used. Feeding rate and frequency were adjusted based on fish biomass and water temperature using Epagri/SC feeding tables. The trial lasted 245 days, and the parameters evaluated included growth performance, yield (fillet and carcass), proximate composition, fillet fatty acid profile, and economic feasibility. Fish fed the ALLPRO diet showed improved feed conversion, highest daily weight gain, increased protein utilization, greater yield, and elevated crude protein and n‐3 PUFA levels, especially DHA, in fillets. Supplementation with 0.22 g of DHA 100 g −1 of diet dry weight resulted in a 10% higher final weight compared to fish fed the control diet without DHA supplementation. Although the inclusion of the additive increased the diet cost, the average production cost per whole fish and fillet was more economically efficient. In conclusion, ALLPRO supplementation enhanced growth, nutritional quality, and economic feasibility in Nile tilapia farming under suboptimal temperatures in field conditions.

The fall armyworm Spodoptera frugiperda (J. E. Smith, 1797) has evolved resistance to different Bt maize technologies carrying Bacillus thuringiensis genes. One hypothesis for the rapid evolution of resistance may be associated with the species' ability to multiply and survive on alternative host plants, especially during the off-season of the main crops. The aim of this study was to evaluate the biological parameters and fertility life table of susceptible (SS), heterozygous (RS) and resistant (RR) strains of S. frugiperda to Bt YieldGard VT PRO maize when kept in summer-winter cover crops. Based on the results, S. frugiperda did not survive on weeds Barnyardgrass (Echinochloa crus-galli). SS, RR, and RS larvae fed on white oats (Avena sativa), ryegrass (Lolium multiflorum), maize (non-Bt isoline) showed an egg to adult generation of approximately 30 d. The RS strain performed better than both the SS and RR strains, this is consistent with the individuals' high heterosis index. In addition, the insects reared on these hosts showed the highest reproductive rates (Ro = 496.2 to 578.1) and growth rates (rm = 0.143 to 0.185). In contrast, sorghum (Sorghum bicolor) or Persian clover (Trifolium resupinatum) prolonged the cycle by 4 d and reduced egg-to-adult viability parameters by 13%, larval weight (0.057 to 0.74 mg), pupal weight (0.36 to 0.86 mg), Ro (196.4 to 324.0), and rm (0.104 to 0.122). However, it is worth noting that all the host plants evaluated, except for Barnyardgrass, can serve to multiply S. frugiperda in the field and favor the reestablishment of the insect during the corn off-season and, consequently, accelerate the evolution of the pest's resistance.

ABSTRACT Identifying resistance sources using fast, sensitive, and standardized methods is key to initiating a breeding program or even a germplasm characterization. To establish the infestation density, the coexistence period, and discriminatory parameters for determining maize tolerance-type resistance to the green-belly stink bug, Diceraeus melacanthus (Hemiptera: Pentatomidae), greenhouse, and field trials were conducted using four maize genotypes (SCS154 Fortuna, SCS155 Catarina, 2B512 PW, and 2B610 PW). In both greenhouse and field trials, plants infested with a density of two adult stink bugs per plant for a coexistence period of seven days was determined to be the optimal conditions for evaluating maize genotypes tolerance. In addition, plant height and fresh weight were significantly reduced in infested plants on greenhouse trial. Conversely, D. melacanthus reduced plant height at the V5 stage and weight of thousand seeds in field trials, but plant height up to tassel, height of cob insertion, and grain yield were not affected, indicating a recovery potential of the tested genotypes. No difference in damage score was verified in the genotypes in both greenhouse and field trials. Biochemical responses of plants infested and non-infested with D. melacanthus from field trial indicated that chlorophyll and carotenoid content were reduced due to stink bug infestation. Moreover, infested plants expressed higher amounts of peroxidase and polyphenoloxidase enzymes. In field, the reduction in phenotypic and productive parameters was similar among the evaluated genotypes, and in general, the tested genotypes exhibited similar response to D. melacanthus attack.

Este estudo teve como objetivo analisar a contaminação por resíduos de agrotóxicos em alimentos comercializados na mesorregião do Vale do Itajaí, Santa Catarina. Para isso, foram analisados os laudos de 433 amostras de 29 alimentos, coletadas entre 2013 e 2018, no âmbito do Programa Alimento Sem Risco (PASR). As amostras foram classificadas em três categorias: sem resíduo, com resíduo (abaixo do Limite Máximo de Resíduo - LMR) ou desconformes (acima do LMR, contendo substância não autorizada - NA, ou de uso proibido - UP). Os dados foram processados para estabelecer um ranqueamento de risco com base na frequência de irregularidades. Os resultados revelaram que 15,9% das amostras (69) estavam desconformes. O pimentão destacou-se como o alimento mais problemático, com 62% de suas amostras consideradas inadequadas, principalmente pelo uso de substâncias não autorizadas (NA). A análise evidenciou a presença de múltiplos resíduos em uma mesma amostra e a detecção de agrotóxicos de uso proibido (UP) no país, como o Metamidofós. Os fungicidas (60,6%) e inseticidas (39,1%) foram as classes predominantes. Tais achados apontam para deficiências sistêmicas na fiscalização e na assistência técnica, reforçando a necessidade urgente de promover sistemas de produção mais sustentáveis e harmonizar os LMRs com padrões internacionais.

The urban area of the town of Xanxerê, state of Santa Catarina, Brazil, faces inundation and flooding problems that demand complex structural measures due to intense urbanization over the natural drainage network. In addition, a large part of the farmland of the rural area presents soil erosion issues and water loss, which contributes to urban inundation. This study evaluated the contribution of the terracing technique in farming areas in reducing maximum runoff in the urban area of Xanxerê, Santa Catarina. Maximum runoffs were determined by the SCS hydrograph method for projected rain and return times of 25, 50 and 100 years. Scenarios such as the present situation were considered, as well as two others, with the implementation of drainage terracing and level terracing in farmlands with annual crops and pastureland. The effect of terracing was evaluated by CN alteration in these areas. For the rural basin, the implementation of gradient terracing reduces peak runoff by about 10%. The implementation of level terracing reduces peak runoff by around 50%. On the other hand, in the entire area of the basin under study, the use of gradient terracing reduced peak runoff by about 7%, while the use of level terracing reduced peak runoff by between 25 to 32%. Results demonstrate that adopting conservationist practices in rural areas can effectively contribute to solving urban drainage problems. Keywords: erosion, soil conservation, terracing.

Os insetos do gênero Bradysia (Diptera: Sciaridae) conhecidos como fungus gnats são pragas de importância crescente em sistemas de cultivo protegido de morangueiro. Para o controle destes insetos-praga, torna-se essencial o uso do monitoramento e de métodos de controle integrados. Neste contexto, este estudo objetivou avaliar a cor de armadilha do tipo Moericke (amarela, azul-clara e azul-escura) mais eficiente na captura de adultos de Bradysia. As coletas dos insetos ocorreram de novembro de 2023 a março de 2025, em Caçador - SC, em cultivo semi-hidropônico de morangueiro ‘Monterrey’ conduzido no sistema convencional. As armadilhas foram distribuídas completamente ao acaso, com quatro repetições por cor, dispostas na mesma altura da bancada de cultivo. Para a contagem dos insetos, amostras de 20 mL de água foram coletadas semanalmente do fundo de cada bacia. Os dados foram submetidos à análise de variância (teste F) e as médias foram comparadas pelo teste de Tukey (p≤0,05). A armadilha de coloração azul-escura foi a mais eficiente na captura de adultos de Bradysia. O monitoramento semanal destes insetos-praga com armadilha do tipo Moericke permite observar os picos populacionais e auxilia na tomada de decisão de controle em cultivos de morangueiro semi-hidropônico.

As coleções entomológicas são essenciais para o uso de informações sobre qualquer grupo de insetos. Definidas como um conjunto de espécimes conservados fora de seu ambiente natural, devidamente preparados e organizados com dados de procedência e identificação taxonômica, elas adquirem o status de coleção científica. Essas coleções representam amostras valiosas da biodiversidade e de diversos nichos ecológicos, sendo fundamentais para a pesquisa e contribuindo significativamente para o desenvolvimento científico e tecnológico da entomologia. Com base nisso, este trabalho teve como objetivo abordar a importância da coleção entomológica, destacando as formas de preservação e identificação de insetos, e demonstrando seu valor para a pesquisa científica e tecnológica, bem como para a conscientização sobre a biodiversidade e o papel dos insetos nos ecossistemas e atividades humanas. No campo, os insetos foram identificados sempre que possível, utilizando guias de identificação e chaves dicotômicas. Posteriormente, os espécimes foram etiquetados com informações relevantes como data, local de coleta e características morfológicas observadas. Coletou-se uma diversidade significativa de insetos, totalizando 24 espécimes identificados em nível de Ordem e Família, abrangendo 14 Famílias distribuídas em 6 Ordens. A Ordem com o maior número de famílias capturadas foi Coleoptera (5), seguida por Orthoptera (4), Lepidoptera (2), Hemiptera (2), Hymenoptera (2) e Mantodea (1). Concluímos que a coleção entomológica é uma ferramenta valiosa para a pesquisa científica e para a conscientização sobre a importância e os impactos dos insetos nas atividades humanas.

This study evaluated the technical and economic feasibility of the biofloc technology (BFT) system during the fry rearing phase of Nile tilapia (Oreochromis niloticus), focusing on suspended solids management, stocking density, and economic performance at a pilot scale. Three trials were conducted. The first assessed the effects of four total suspended solids (TSS) ranges (0-200, 200-400, 400-600, and 600-800 mg·L-1) on larval performance and water quality. TSS levels between 200 and 600 mg·L-1 promoted improved water quality and zootechnical performance. The second trial tested five stocking densities (2, 4, 6, 8, and 10 larvae·L-1), evaluating their impact on water quality, survival, and size uniformity. Higher densities negatively affected survival (R2 = 0.84) and final weight (R2 = 0.92), while also increasing solids and nitrogenous compounds, thus impairing performance (p < 0.05). The third trial monitored six production cycles at pilot scale, evaluating zootechnical parameters, sex reversal efficiency, and economic indicators. All cycles showed survival rates above 85%, sex reversal close to 100%, and positive net margins (18.5 to 41.9%), demonstrating the viability of BFT for commercial fry operations. The results emphasize the importance of controlling suspended solids and stocking density to maintain water quality and optimize larval performance. Furthermore, the system proved economically viable, with good feed conversion rates and profitability, even without water exchange. These findings support BFT as a sustainable and efficient alternative for tilapia fry production, offering significant water savings and promising economic returns when properly managed.