Antônia Alice Costa Rodrigues

Entomopathogenic fungi Metarhizium anisopliae and Beauveria bassiana and the egg parasitoid Telenomus podisi are complementary strategies for managing the brown stink bug, Euschistus heros. This study evaluated fungal virulence against E. heros and selectivity to T. podisi in two experiments: (1) virulence assessment of M. anisopliae (CG 168; IBCB 425) and B. bassiana (LPP 129; LPP S1) applied at 1×10⁸ viable conidia mL⁻¹; and (2) selectivity tests in which eggs were immersed in fungal suspensions before (pre-parasitism) and after (post-parasitism) oviposition by T. podisi. Isolates CG 168 and IBCB 425 prolonged egg incubation and significantly reduced egg viability, with CG 168 showing hatching below 5%. At the nymphal stage, all isolates were pathogenic, and CG 168 and LPP 129 were the most virulent, causing higher mortality and shorter lethal times. In adults, CG 168 was the most effective, reducing survival to 8% by day seven, whereas IBCB 425, LPP 129, and LPP S1 caused intermediate effects, with 30–32% survival. Control treatments and Tween 80 maintained high survival. Fertility varied among isolates, increasing under LPP S1 and decreasing under LPP 129. Regarding selectivity, CG 168 reduced parasitism and emergence of T. podisi when applied after parasitism, whereas IBCB 425 showed performance similar to the control. Overall, CG 168 is highly effective against E. heros but shows low selectivity to T. podisi, while IBCB 425 combines efficacy and compatibility with the parasitoid, supporting its use in integrated management of the brown stink bug in soybean crops under agricultural production systems conditions.

Plants possess several molecular mechanisms that enable them to adapt their development to environmental changes. Many plant biological processes depend on the circadian rhythm and are regulated by the internal biological clock. Predictable environmental changes, such as variations in photoperiod, can modulate circadian rhythms, allowing organisms to synchronize their biological processes with seasonal conditions. Plant tissue culture is a valuable tool for investigating and monitoring plant plasticity in response to environmental fluctuations, as well as for elucidating the biological changes that occur under these conditions. This review highlights the importance of in vitro culture as a tool to study the physiological plasticity triggered by photoperiod and its interaction with the plant biological clock. To achieve this, a descriptive analysis was conducted through a literature search in the Scopus database, followed by a bibliometric analysis to demonstrate the progress in the application of in vitro culture to studies on photoperiod and circadian regulation in plants.

Coriander (Coriandrum sativum L.), an aromatic leafy vegetable from the Apiaceae family, is globally renowned for its flavorful leaves and medicinal properties (Mahleyuddin et al. 2022). In Brazil, coriander cultivation faces challenges like seedling damping-off and leaf burn, symptoms frequently linked to Fusarium wilt, caused by F. oxysporum, in other countries (Koike and Gordon, 2005; Li et al., 2021). Since 2018, a rise in leaf chlorosis, wilting, and mortality has been noted in coriander cultivars Verdão and Verdão Super in Maranhão, Brazil, particularly in the municipalities of São Luís (2°34'01"S, 44°16'00"W) in August 2018 and Formosa (4°50'60"S, 46°44'00"W) in March 2021, affecting up to 70% of 20–25-day-old field plants. To investigate it further, ten symptomatic plants were randomly collected from Formosa and ten from São Luís, then sent to the Plant Pathology Laboratory at the State University of Maranhão. From symptomatic tissues of each sample, vascular fragments (1 x 1 cm) were disinfected (70% alcohol, 1% sodium hypochlorite, and sterile water) and cultivated on Potato Dextrose Agar, then incubated (25°C - 12 h light/dark cycle). After five days, rapidly growing pink colonies appeared in all isolated fragments, and then microscope slides were prepared to observe the fungal structures, where short monophialides and unicellular, elliptical microconidia were observed, measuring 14–25 µm in length (mean = 20.55 µm) and 36.4–55.4 µm in width (mean = 48.6 µm) (n = 20). Macroconidia, slightly curved with three septa, measured 116–467 µm in length (mean = 370 µm) and 28.8–51.3 µm in width (mean = 42.78 µm) (n = 20). Chlamydospores were also observed terminal or intercalary in hyphae. Single-spored isolates were molecularly identified and tested for pathogenicity. DNA was extracted using Zymo Research® kit, and TEF-1α, ITS, and IGS regions were amplified using PCR. The primers used were EF1-728R/EF2 for TEF-1α (Carbone & Kohn, 1999), ITS1/ITS4 for ITS (White et al., 1990), and Inl11/FoIGS-R for IGS (O’Donnell et al., 2009). Amplicons were sent to ACTGene company and sequenced by Sanger, submitted to GenBank, and analyzed phylogenetically. The accession numbers are MGSS 305 (OR102500, OR859840, PQ468316), MGSS 415 (OR102501, OR859842, PQ468317), and MGSS 416 (OR102502, OR859841, PQ468318). Bayesian analysis confirmed that the isolates belong to the F. oxysporum species complex. Pathogenicity tests involved two coriander varieties (Verdão and Verdão Super), totaling 200 plants, with 25 per isolate (MGSS 305, MGSS 415, MGSS 416 and control)/ variety combination. Thirty-day-old seedling roots were dipped in a conidial suspension of 1 x 106 conidia/mL for 20 min; while the control group was treated with sterile water (Reis et al., 2004). Plants were grown in 3 L pots with sterilized soil, in a greenhouse at 25 ± 2°C, 60% RH, and a 12 h photoperiod. After 21 days, wilt incidence occurred in the inoculated plants: MGSS 415 and MGSS 416 infected both varieties, where we observed an incidence between 80% and 92% in Verdão and 96 and 100% in Verdão Super, and MGSS 305 showed less than 20% incidence in both varieties. Control plants remained healthy. Reisolation confirmed the pathogen via morphology, molecular data (Figures 1 and 2), and pathogenicity, identifying it as F. oxysporum f. sp. coriandrii (Gilardi et al. 2017; Koike and Gordon 2005). The experiment was conducted twice at different times, and similar results were observed. This finding underscores the need for further research and the development of mitigation strategies to protect this crop.

A implantação do Núcleo de Estudos em Agroecologia e Produção Orgânica do Maranhão da Universidade Estadual do Maranhão - UEMA objetivou divulgar as práticas agroecológicas desenvolvidas pelo Programa de Pós-graduação em Agroecologia. Foram instaladas unidades demonstrativas de janeiro/2020 a outubro/2022 no campus São Luís em São Luís – MA. Constatou-se a capacitação de agricultores familiares, estudantes e pesquisadores quanto a construção de sistemas agrícolas biodiversos e resilientes.

Platonia insignis, a native tree from the Amazon, has a high market demand due to its various uses, such as producing pulps and ice creams from its fruit and furniture from its wood. This review aims to systematize the scientific knowledge about the species and explore the potential of biotechnology to elucidate its growth, development, and fruiting mechanisms. Databases such as the Web of Science, Scopus, the Brazilian Agricultural Research Database, and PubMed were consulted using keywords like “P. insignis”, “bacuri”, and “bacurizeiro”. Of the 67 selected articles, it was observed that rigorous research on P. insignis is limited. Current management is based on empirical observations, but biotechnology could expedite the domestication process. Additionally, studying medicinal compounds from P. insignis could open new economic opportunities, encourage germplasm conservation, and drive genetic breeding.

A significant knowledge gap exists regarding how beneficial microorganisms affect in vitro plant cultivation. Although aseptic conditions are essential, they exclude microorganisms that could enhance plant growth and acclimatization. This study aimed to evaluate the effects of inoculating Bacillus methylotrophicus and Serratia marcescens on the in vitro growth and development of Stryphnodendron adstringens, a tree with high medicinal value. We grew S. adstringens plants in vitro with four treatments: control, B. methylotrophicus, S. marcescens, and a combination of both. After 45 days, we measured chlorophyll a fluorescence, growth (shoot length, biomass, and leaf area), and acclimatization rate. Then, plants were transferred to ex vitro conditions and monitored for 20 days. Plants inoculated with B. methylotrophicus and S. marcescens showed higher chlorophyll a fluorescence and significantly longer shoots (57% and 35%, respectively) compared to the control. S. marcescens also promoted the highest root biomass, with increments of 158% more fresh mass and 180% more dry mass than the control. Most strikingly, plants treated with both bacteria had a 100% survival rate during acclimatization, representing a 40% increase over the control. These findings show that plant growth-promoting bacteria, particularly S. marcescens, can enhance in vitro growth and improve acclimatization. This research supports more efficient micropropagation and advances the biotechnology of native tree species.

Ever-increasing industrial demand means that forest stands and the number of areas with Eucalyptus plantations are growing rapidly in Brazil and worldwide. This has increased the use of genetic materials, increasing the incidences of pests and diseases. Wilt is caused by the Ceratocystis fimbriata fungus, which is one of the most common diseases in Eucalyptus plantations. This study aimed to evaluate the ecophysiological responses of clonal seedlings of Eucalyptus spp. inoculated with different C. fimbriata isolates. The treatments were LPF 1512, 1806, 1607, and 1657 from the states of São Paulo, Minas Gerais, Bahia, and Mato Grosso do Sul, respectively, and a control comprising distilled water. Fungal isolates were inoculated 60 days after seedling planting. After inoculation, the growth, gas, leaf temperature, and chlorophyll a fluorescence were analyzed. Regardless of the isolate, inoculation with C. fimbriata increased water flow resistance in the xylem vessels of Eucalyptus plants, causing water stress. This results in reduced gas exchange and compromised photosynthetic performance, as evidenced by decreased absorption flux per reaction center and low photosynthetic index values. Furthermore, fungal pathogenicity analysis indicated that the LPF 1657 isolate was most virulent to Eucalyptus seedlings, directly affecting the height, photosynthetic CO2 assimilation, stomatal conductance, and transpiration of the inoculated plants.

A mandioca é um alimento de importância social no Maranhão, pois compõe a base da alimentação da população. A produtividade média da cultura no estado é considerada baixa, inferior a 8,6 t ha-1. O desafio é, portanto, aumentar a produtividade da cultura por meio do manejo da adubação. Os objetivos foram determinar a dose de fertilizante orgânico que promove a maior produtividade de mandioca, validar a dose de fertilizante mineral que está sendo utilizada na região, e avaliar os efeitos da combinação entre os fertilizantes orgânico e mineral nos componentes relacionados à produção e nutrição foliar. O experimento foi conduzido em delineamento de blocos ao acaso, arranjados em esquema fatorial 2 × 5, com quatro repetições. Os fatores foram duas combinações de adubação mineral (com e sem NPK) e cinco doses de esterco bovino (0, 2,5, 5,0, 7,5 e 10,0 t ha-1). Os resultados indicaram que as doses de fertilizante mineral NPK utilizada para a região resultou em aumento na produtividade da mandioca, confirmando a hipótese de que a recomendação de NPK pode ser adotada para a região. As doses superiores a 4,5 t ha-1 de esterco bovino podem gerar desequilíbrios nutricionais, refletindo em menores teores de nitrogênio e fósforo nas folhas. Foi possível concluir que a aplicação combinada de fertilizantes, dentro das doses recomendadas, otimiza a produtividade da mandioca e pode orientar práticas agrícolas sustentáveis para a garantir a segurança alimentar na região do Maranhão.

Rice landrace varieties are adapted to the most diverse environmental conditions, which is clearly important in periods of great climatic and sanitary uncertainties. However, there is a gap in their description in the literature. Maranhão, Brazil, has wide diversity in landrace seeds, with rice varieties that can significantly contribute to the genetic breeding of the species. Based on this information, the objective of the present study was to characterize the landraces rice varieties, through the description of the morphological and agronomic profile. The study analyzed 23 qualitative heredity descriptors and three quantitative descriptors in 21 rice landrace varieties from different locations in the state of Maranhão, according to the methodological procedures recommended by the National Cultivar Protection Service. A randomized block e experimental design was used (DBC), with 21 treatments and four replications. Considering complementing To complement the study, a multicategorical analysis was carried out between the 21 accessions, based on qualitative data obtained from the 22 morphological descriptors, which generated a dendrogram. The results showed that there are differences between the qualitative descriptors. Quantitative descriptors are highly significant, with regard to the number of tillers, with emphasis on the Edinho variety. The Quechi variety was responsible for one of the factors that most influences the rice yield, with the highest number of grains per panicle. The varieties Codozinho, Edinho, Palha Murcha and Pé Roxo, are more productive in number of panicles. The dendrogram formed three clusters with evidence of dissimilarities between the varieties. The results show that the landrace varieties differ in their morphoagronomic characteristics and can be valuable materials in the construction of a new, more sustainable agriculture.