Larisse Raquel Carvalho Dias

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.

Objetivou-se nesse trabalho avaliar a qualidade sanitária das sementes de feijão-caupi (Vigna unguiculata L. Walp.) utilizadas na região Meio-Norte do Brasil, verificar o efeito do tratamento de sementes com óleo essencial de Lippia lasiocalycina no controle de fungos nas sementes, bem como seu efeito sobre a germinação. A qualidade sanitária das sementes foi obtida com o Teste de Sanidade de Sementes (TSS) em 111 amostras. Para o controle dos microrganismos foi utilizado o óleo essencial Lippia lasiocalycina, sem diluição, nas seguintes concentrações: 0 (sem óleo); 0,5; 1,0; 2,0; e 4,0 mL Kg-1de semente. O TSS revelou a presença de Alternaria sp., Aspergilus spp., Cladosporium sp. Curvularia sp., Lasiodiplodia theobromae, Macrophomina phaseolina, Penicillium spp., leveduras, Phoma sp., Fusarium spp, Rhizoctonia solani e Rhizopus stolonifer. As sementes apresentam qualidade sanitária considerada regular. Todos os fitopatógenos foram controlados pelo óleo essencial na concentração de 3 mL Kg-1 de sementes, entretanto, essa concentração do óleo essencial afeta negativamente o poder germinativo das sementes. Para o controle específico de Fusarium foram utilizadas sementes da Cultivar BRS Guariba, naturalmente infestadas com incidência média de 87%.

Cowpea is one of the main crops in family agriculture, especially in the Northeastern region of Brazil, and it is expanding to other regions in Brazil. The use of seeds with low physiological and health quality is reflected in the plant development and consequently yield, making it important to study the seed physiological and health quality. The objective of the present study was to assess the physiology and health of traditional and biofortified cowpea seeds. The traditional cowpea varieties (Angelim, Mercado and Manteguinha) and the biofortified cowpea cultivars (BRS Aracê, BRS Xique-Xique and BRS Tumucumaque) were assessed for the following physiological parameters: water content (WC), first count (FC), germination test (G), germination speed index (GSI), seedling emergence in the greenhouse (E), emergence speed index (ESI), seedling aerial part and root length (APL and RL) and electric conductivity test (EC). The seed health quality was assessed by the Blotter Test. The water content present in the seeds of the traditional and biofortified varieties ranged from 10% to 14%. All the traditional and biofortified varieties showed high germination and emergence value in the greenhouse. The germination and emergence speed indexes indicated the BRS Aracê and BRS Xique-Xique cultivars as the most vigorous. In the health tests the highest indexes were the storage fungi Aspergillus sp., Cladosporium sp. and Penicillium sp., with the highest prevalence in the BRS Tumucumaque variety, which was probably related to the higher water content present in this variety.

Essential oils have been widely studied because they are natural sources of substances that have antimicrobial properties. In fruit growing, especially in mango crop, anthracnose (Colletotrichum gloeosporioides) is considered the main disease because it causes series of damages in the fruit production chain and, in this sense, essential oils can be an option in this disease control. The objective of this study was to evaluate the effect of essential oils obtained from the leaves of Chá-de-moça (Pectis brevipedunculata) and Melosa (Dizygostemon riparius) in the in vitro and in vivo control of the C. gloeosporioides fungus, in seedlings and mango fruits. The in vitro bioassays were performed by testing the effect of different concentrations of essential oils (0, 1, 2, 3 and 4 µl/mL) on the reduction of mycelial growth of the C. gloeosporioides fungus. Additionally, the anthracnose control in mango seedlings (Tommy Atkins, Constantina, Comum and Rosa cultivars) was evaluated by foliar application of essential oils at 4 µl/mL concentration. Disease control in fruits of the same mango cultivars was evaluated at 3 µl/mL concentration of essential oils. The evaluation was carried out by measuring the average diameter of the colonies, for the in vitro treatment, and the lesions for the in vivo treatments, in two diametrically opposite directions. There was a decrease in the fungus mycelial growth in all tested concentrations. There was a decrease in the disease severity from the sixth day after the oils application in Tommy Atkins cultivar seedlings, when treated with both essential oils at 4 µl/mL concentration. As for preventive treatments with fruits, it was observed that all cultivars achieved a reduction in severity from 54.83% at 3 µl/mL concentration with the use of both essential oils. Given the results obtained, it was observed that the essential oils P. brevipedunculata and D. riparius can be a viable alternative in the anthracnose control in mango culture.