Pro-embrionary Somatic Structure of Three Cacao Genotypes (Theobroma Cacao l.) Using Staminodes

Staminodes of three cocoa genotypes (BT1, ICS-39 and CCN-51), were used to perform the characterization of somatic embryos induced and maintained by DKW culture medium enriched with 2% of sucrose, 10% of coconut water and 0.01% of cysteine, 2,5 mg/l 2,4 D, 5 µg/lTDZ respectively. The ANOVA and the comparison mean test, shown significant differences between globular-, heart-, torpedo- and cotyledonal-stages for each genotype. Additionally, the embryogenic stages and regenerants plants proportions were highest for Blanco Tarapotino 1 (BT1) genotype. A morphological comparison of somatic and zygotic embryos shows similarities in form and symmetry

Relação entre o conteúdo relativo de água, densidade estomática e formação de cera epicuticular em folhas de plantas micropropagadas de bananeira.

No processo de micropropagação, a realização de uma fase de aclimatização ex vitro logo após a remoção das plantas dos recipientes de cultivo tem sido considerada imprescindível para o pleno sucesso desta técnica. Isso porque durante este período de adaptação, as anormalidades morfológicas e/ou fisiológicas induzidas durante o crescimento in vitro são parcialmente ou completamente corrigidas. Entre as alterações geralmente observadas, a falta ou reduzida produção de cera epicuticular em associação com a baixa regulação estomática são os principais fatores reportados como responsáveis pela alta mortalidade das plantas micropropagadas, já que possuem importante papel regulatório sobre a excessiva transpiração das plantas (Cappelades et al., 1990; Romano & Martins-Loução, 2003). Diante desse contexto e devido aos poucos estudos a esse respeito, objetivou-se avaliar as respostas de diferentes tipos de folhas quanto à perda de água e sua relação com os estômatos e formação de cera epicuticular em plantas de bananeira micropropagadas

Pb and Cd on growth, leaf ultrastructure and essential oil yield mint (Mentha arvensis L.)

Contamination of medicinal plants with heavy metals as Pb and Cd can affect the growth and the essential oil production of the plants and represent a risk to those who consume as medicine. This study aimed to evaluate the effects of absorption and localization of Pb and Cd on growth, ultrastructural aspects of leaves and essential oil yield and composition of Mentha arvensis, applied on the soil with increasing concentrations (8, 16, 32, 64 and 128mg kg-1). There was a differential absorption of Pb and Cd by M. arvensis mainly concentrated in the roots. Pb was found in small amounts in the leaves while Cd largely exceeded the safety limit without symptoms of toxicity. The ultrastructural analysis revealed the metal accumulation on vesicles surrounding the mitochondria and the presence of electron dense deposits surrounding the mitochondria, nucleus and chloroplasts. Little changes caused by Pb and Cd application were not enough to affect the growth and essential oil yield and composition of M. arvensi