Identification of Coumarins and Antimicrobial Potential of Ethanolic Extracts of Dipteryx odorata and Dipteryx punctata.

Dipteryx odorata and Dipteryx punctata are species native to the Amazonian, traded by extractivists to obtain coumarin. We aimed to analyze the presence of coumarin in the ethanolic extracts of leaves, branches and fruits of D. odorata and D. punctata and to evaluate the antimicrobial activity of these extracts against phytopathogenic fungi and bacteria of clinical interest. Chemical analyses were performed by thin layer chromatography (TLC) and by gas chromatography coupled to mass spectrometry (GC-MS). For the antifungal assays, the fungi used were Cercospora longissima, Colletotrichum gloeosporioides, two isolates of Fusarium spp. and Sclerotium rolfsii, and the antibacterial assay was performed using the minimum inhibitory concentration (MIC) test with Burkholderia cepacia, Escherichia coli, Pseudomonas aeruginosa and Staphylococcus aureus bacteria. In D. odorata seed extracts and in D. punctata husks, endocarps, and seeds, we identified 1,2-benzopyrone. D. odorata endocarp extracts and D. punctata seeds provided the greatest decrease in mycelial growth of the evaluated phytopathogens, showing promise as an alternative control. The husk and endocarp extracts of both species had a weak effect on E. coli. This research is the first to compare the different parts of species of the genus Dipteryx and to evaluate the use of husks and endocarps of D. punctata fruits to obtain coumarin. Chemical analyses used to quantify the compounds existing in the extracts, and tests with phytopathogens in vitro and in vivo are currently being carried out.

Evaluation of Trichoderma spp. Isolates in Cocoa Seed Treatment and Seedling Production.

Isolates of Trichoderma spp., a soil fungus, has been used to control diseases and promote plant growth, reducing the use of chemicals in the production of seedlings of different plant species. We evaluated the effect of some Trichoderma spp. isolates on seed treatment and seedling production of Theobromacacao. Five isolates from the Amazon region were tested. In laboratory, the following variables were evaluated for seed treatments: germination, germination speed index, radicle and hypocotyl lengths, and fungi incidence. In nursery, the following forms of application were tested: via seeds; in the substrate at pre-planting; monthly in post-planting substrate, and also their combination. The following was evaluated: height, diameter, number of leaves, root length, leaf area, and shoot dry mass and root system. Inoculation with Trichoderma increased the length of the radicle and hypocotyl and showed no fungi in the seeds. In seedlings, some treatments increased height and plant root dry mass. The use of Trichoderma was beneficial for seeds and appeared favorable for T. cacao production.

Trichoderma spp. on treatment of Handroanthus serratifolius seeds: effect on seedling germination and development.

Fungi of the genus Trichoderma are important microorganisms used in biocontrol processes and the promotion of plant development. However, they remain poorly studied in the context of forestry programs, especially those related to native Amazonian species. Thus, it is the aim of this study to evaluate the effects of different Trichoderma isolates on the germination and development of Handroanthus serratifolius seedlings. During in vitro germination tests, seeds were immersed for 24 h in respective fungal suspensions each prepared using one of five Trichoderma isolates. The suspensions were held in plastic trays and kept at a temperature of 24 ± 2 °C. Metrics related to germination and development assessed under laboratory conditions include: germination speed index (GSI), germination percentage, length of the roots, and hypocotyls, as well as fungal perseverance. In the nursery, Trichoderma were used in two different applications: pre-planting treatment and as a monthly, post-planting treatment. Pre-planting treatments consisted of 10 g of colonized rice grains bearing each isolate being placed into experimental bags five days before seeding. The post-planting treatment involved the application of 10 mL of fungal suspension per experimental bag. Each month, the height, stem diameter, and leaf number were measured for each seedling. At the end of the experiment, the length and mass of roots as well as the total dry mass were recorded. In laboratory conditions, seeds treated with Trichoderma asperellum -TAM03 obtained the greatest fractional germination (76.5%) and GSI. In the nursery experiments, isolates TAM01 and TAM03, when applied as a post-planting treatment, increased the height, stem diameter, and number of leaves of treated plants with respect to the control group by 180 days post-treatment. After 365 days, plants which received TAM01 pre-planting treatments were observed to have increased root and aerial part length, as well as root mass and overall dry mass. These results suggest that T. asperellum -TAM01 positively affects H. serratifolius development.

Hemibeltrania urbanodendrii sp. nov. and Pseudobeltrania angamosensis: new fungal records from the brazilian tropical seasonal semi-deciduous montane forest

The new species Hemibeltrania urbanodendrii, associated to leaf-spots on Urbanodendron verrucosum (Lauracea) and Pseudobeltrania angamosensis, associated with leaf-spots on Virola gardneri (Myristicaceae), are recorded for the first time in Brazil. They represent additions to the mycobiota of the Tropical Seasonal Semi-Deciduous Montane Forest in Viçosa (Minas Gerais, Brazil), a highly threatened ecosystem.

Novas ocorrências de fungos relacionados a manchas foliares são apresentadas: Hemibeltrania urbanodendrii sp. nov., associado a Urbanodendron verrucosum (Lauracea) e Pseudobeltrania angamosensis, associado a Virola gardneri (Myristicaceae). Eles representam adições à micobiota da Floresta Tropical Estacional Semidecidual Montana de Viçosa (Minas Gerais), um ecossistema fortemente ameaçado.