Chemical characterization and in vitro biological activity of Cymbopogon citratus extracts against Haemonchus spp. and Trichostrongylus spp. nematodes from sheep.

Medicinal plants have been the focus of several studies due to their nematicide properties which can be used to control nematodes in sheep. No study has examined the morphological effects of Cymbopogon citratus on nematodes. Thus, this study evaluated the chemical composition, nematicidal activity and effects of C. citratus extracts on the morphology of eggs and infective larvae (L3) of sheep. Aqueous and methanolic extracts and fractions of C. citratus were obtained and analysed in vitro. The C. citratus extracts were effective against Haemonchus spp. and Trichostrongylus spp. larvae and eggs. Ten fractions were obtained from C. citratus, six of which had high ovicidal activity at 1000 µg mL-1, and two fractions had high activity at all tested concentrations. The phytochemical analysis identified the presence of compounds such as terpenoids, various ketones, esters, and fatty acids. The ultrastructural analysis showed deformations of the cuticle and wilting along the body of the nematodes at all concentrations. The muscular layer, intestinal cells and the mitochondria profile showed damage compared to the typical pattern. Ultra-thin sections of eggs treated with methanolic fractions of C. citratus presented modifications. This study showed the biological activity and effects of C. citratus on the gastrointestinal nematodes in sheep.

Effect of packaging materials and storage environment on fennel seedling growth / Efeito da embalagem e do ambiente de armazenamento no crescimento de plântulas de erva doce

The objective of the present study was to assess the influence of the packaging material (cotton cloth bag, multifolium paper and glass container) and storage environment (laboratory and cold chamber conditions) on fennel seedling growth. Seeds were placed in different packaging materials and exposed to the two environments for twelve months. Assessments were made before storage and at every two months and the following were determined: total emergence, emergence speed index, seedling fresh and dry matter. A completely randomized experimental design was used, with four replications in a 2 x 3 x 6+1 factorial design in split split plots, where the plot was the storage environment (laboratory and cold chamber conditions); the split plot was the storage (cotton cloth bag, multifolium paper and glass container) and the split plot was the storage periods (2, 4, 6, 8, 10 and 12 months) and plus an additional treatment (before storage). The results showed that the fennel seedlings had superior growth when their seeds were placed in the glass packaging material, regardless of the storage environment.

O objetivo deste trabalho foi avaliar a influência da embalagem (saco de algodão, papel multifoliado e vidro) e do ambiente de armazenamento (condições de laboratório e câmara fria) no crescimento de plântulas de erva doce. Para isso, as sementes foram acondicionadas nas diferentes embalagens e expostas aos dois ambientes durante doze meses. As avaliações foram feitas antes do armazenamento e a cada dois meses, tendo sido determinado: emergência total, índice de velocidade de emergência, massa fresca e seca das plântulas. Utilizou-se o delineamento experimental inteiramente casualizado, com quatro repetições, num esquema fatorial 2 x 3 x 6 + 1 em parcelas subsubdivididas, no qual a parcela foi o ambiente de armazenamento (condições de laboratório e câmara fria); a subparcela as embalagens (saco de algodão, papel multifoliado e vidro) e a subsubparcela os períodos de armazenamento (2, 4, 6, 8, 10 e 12 meses) e mais um tratamento adicional (antes do armazenamento). Pelos resultados, demonstrou-se que as plântulas de erva doce apresentaram crescimento superior quando suas sementes foram acondicionadas na embalagem de vidro, independente do ambiente de armazenamento.