A preliminary investigation of endophytic fungal diversity at Hope, East Coast Demerara, Guyana

Foliar endophytic fungi spend a part of their life cycle on the leaves of plants. They may demonstrate no apparent symptoms but may also cause disease at a later time in the plant’s life. Studies investigating foliar fungal endophytes of mangroves are limited. Therefore, the purpose of this study was to investigate the foliar fungal endophytes present on the leaves of three mangrove species: namely Red mangrove (Rhizophora mangle), Black mangrove (Avicennia germinans) and White mangrove (Laguncularia racemosa). The study site was an area located at Hope, East Coast Demerara, and South America, Guyana. Out of sixty (60) leaf samples that were prepared, fourteen (14) fungal isolates were identified. Most of the fungi isolated in the study were found to be Hyphomycetes (Aspergillus, Fusarium, Penicillium, Alternaria, Cladosporium and Curvularia) while the others were Zygomorphic (Mucor and Rhizopus). The ANOVA calculations for the isolates from the three mangrove species were found to not be statistically significant. R mangle was the preferred host out of the three (3) species. The findings of this study confirm that mangroves have rich endophytic diversity and demonstrate rich research and biochemical potential.

Mudas de Mangue Branco Irrigadas com Água de Rejeito de Salina Solar em Substrato Areia de Restinga para Replantio de Manguezais Degradados

A necessidade de repovoar áreas de mangue degradadas pela produção de sal marinho levantou a questão da viabilidade da produção de mudas de mangue branco (Laguncularia racemosa (L.) C. Gaertn) com água e substrato obtidos próximos aos manguezais. Para tanto, foram testados o substrato Areia de Restinga e suas misturas com proporções de 25 e 50% de fibra de coco, bem como irrigação com água doce ou água contendo 5% e 10% de água de rejeito de salina com alta concentração de sal (água-mãe). O delineamento experimental foi o inteiramente casualizado em esquema fatorial, os dados foram analisados por meio da análise de variância e as médias foram comparadas pelo teste de Tukey. As avaliações foram realizadas em cinco períodos de desenvolvimento de plântulas e incluíram massa seca total, altura de planta, diâmetro de caule, massa seca da parte aérea, massa seca da raiz e índice de qualidade de Dickson. O substrato de areia de restinga e a irrigação com água doce proporcionaram as melhores dimensões e qualidade das mudas de mangue branco, mas mudas de tamanho e qualidade muito próximos foram produzidas quando a água aplicada continha 5% da água salgada. Os resultados obtidos serão aplicados para a produção de mudas de mangue branco, economizando água de boa qualidade e reduzindo custos com substrato comercial. Palavras-chave: Degradação Ambiental. Viveiro Florestal. Ambiente Salino. Abstract The need to repopulate mangrove areas degraded by sea salt production has raised the question of the viability of producing white mangrove (Laguncularia racemosa (L.) C. Gaertn) seedlings with water and substrate obtained near the mangroves. Therefore, the substrate Restinga Sand and its mixtures with proportions of 25 and 50% of coconut fiber were tested, as well as irrigation with freshwater or water containing 5% and 10% saltworks brine with high salt concentration (bittern). The experimental design was completely randomized in a factorial scheme. Data analysis consisted of variance analysis and Tukey Test for comparison of means. Evaluations carried out in five periods of seedling development included total dry mass, plant height, stem diameter, shoot dry mass, root dry mass, and Dickson quality index. Restinga Sand substrate and irrigation with freshwater provided the best dimensions and quality of white mangrove seedlings, but seedlings of very close size and quality were produced when the applied water contained 5% of the saltworks bittern. The obtained results will be applied to produce white mangrove seedlings saving good quality water and reducing costs with commercial substrate. Keywords: Environmental Degradation. Forest Nursery. Saline Environment.

Antidiabetic activity of herbal green tea extract from white mangrove (Avicennia marina) leaves towards blood glucose level of diabetic wistar rats (Rattus novergicus)

Green tea Camellia sinensis contains polyphenol that has antidiabetic activity. Mangrove leaves also contain polyphenol which potentially gives these leave antidiabetic activity. The aim of this research was to determine the ability of herbal green tea extract from white mangrove (Avicennia marina) leaves to decrease blood glucose level of diabetic Wistar rats (Rattus novergicus). The method used was experimental and involved giving a herbal green tea extract from white mangrove leaves with concentration of 100, 200 and 300 mg/200g BW/day, and positive control, i.e. glybenclamid (0.09 mg/200 g BW/day), to diabetic rats injected with Streptozotocin (STZ) and Nicotinamide (NA). The rats were observed on day 0, 5, 10 and 15. The results showed that the herbal green tea extract from white mangrove leaves decreased the blood glucose level of diabetic rats. The effective extract dose that decreased the blood glucose level of diabetic rats was 300 mg/200 g BW, which is comparable to the effect produced by glybenclamid (antidiabetic medicine). This dose could decrease the blood glucose level of diabetic rats to reach a normal blood glucose level after 20 days.

Prospección alimentaria del mono araña (Ateles geoffroyi) en petenes del humedal costero de Campeche, México/ Alimentary prospection of the spider monkey (Ateles geoffroyi) in petenes of costal wetland of Campeche, Mexico

For an inter-seasonal 4-month period, we recorded the parts of plant species consumed by a troop of 16 spider monkeys (Ateles geoffroyi) in three forest fragments in the western wetland of the Yucatan Peninsula. In these forest fragments, spider monkeys ate vegetal parts of five plant species: leaves and fruits of fig (Ficus maxima) and zapote (Manilkara zapota), leaves and flowers of white mangrove (Laguncularia racemosa), leaves of huano palm (Sabal yapa), and fruits of chechem (Metopium brownei). With exception of the latter, plant species consumed by spider monkeys in the forest fragments studied, constitute the most important forest resources in the regional wetland. Consumption of vegetal parts from white mangrove in our study sites represents the first record of this plant species in the diet of spider monkey within the Neotropics.