Suelen Santos Rego

Germinação de sementes de Blepharocalyx salicifolius (H.B.K.) Berg. em diferentes substratos e condições de temperaturas, luz e umidade

O objetivo deste trabalho foi verificar a influencia de diferentes temperaturas (20oC, 25oC, 30oC e 35oC), substratos (rolo de papel, papel-toalha, areia e vermiculita), condicoes de luz (ausencia e presenca) e umidade (substratos pouco umido, umido, muito umido e encharcado) sobre a germinacao de sementes de Blepharocalyx salicifolius. Os melhores resultados sao obtidos com os substratos papel toalha, vermiculita e areia, nas temperaturas 20oC e 25oC, e com o substrato rolo de papel na temperatura 30oC. As sementes germinam tanto na presenca como na ausencia de luz, bem como em substrato umido, muito umido e encharcado, nas temperaturas 20oC e 25oC.

Morphological characterization of the fruit, the seed and seedling development of Blepharocalyx salicifolius (HBK) Berg. and Myrceugenia gertii Landrum - Myrtaceae

O objetivo neste trabalho foi caracterizar morfologicamente os frutos, as sementes e o desenvolvimento da plântula de Blepharocalyx salicifolius e Myrceugenia gertii. Para descrever os frutos e sementes foram utilizadas 100 unidades e para a descricao do desenvolvimento da plântula foram colocadas para germinar 100 sementes em substrato papel toalha, a temperatura de 25 oC e 50 sementes em substrato vermiculita. Os frutos de B. salicifolius e M. gertii sao carnosos e indeiscentes do tipo bacoide. As sementes de B. salicifolius possuem forma de espiral, coloracao castanha semitransparente, nao possuem endosperma e o embriao e do tipo pimentoide. As sementes de M. gertii sao ovaladas, de coloracao castanha semitransparente, comprimidas lateralmente, o endosperma e mucilaginoso e o embriao e do tipo mircioide. A germinacao de ambas e epigea fanerocotiledonar.

Detecção, transmissão e patogenicidade de fungos em sementes de Blepharocalyx salicifolius (H.B.K.) Berg.

The objective of this study was to identify the fungi associated with the fruit and seeds of Blepharocalyx salicifolius and verify their transmission and pathogenicity to seeds and seedlings. Fungal identification on seeds was made using the blotter test and potato-dextrose- agar but only the blotter test was used for fruit. Fungal transmission to seedlings was evaluated using four replications of 50 seeds planted in vermiculite. The pathogenicity of the fungi, Colletotrichum sp., Curvularia sp., Cladosporium sp. Pestalotia sp. and Macrophomina sp. was tested. Potentially pathogenic and saprophytic fungi were found on the fruits and seeds. The transmission of Cladosporium sp. from seeds to seedlings was verified, and Cladosporium sp. Pestalotia sp. and Macrophomina sp. were found to be pathogenic to B. salicifolius seedlings.

Caracterização morfológica de frutos, sementes e plântulas de araticunzeiro (Annona crassiflora Mart - Annonaceae)

Araticum (Annona crassiflora Mart. - Annonaceae) is a species with great ecological importance and potential for fruit production. Its fruits, seeds and seedlings were morphologically described in this article as being the main objective of this study. To describe and illustrate the examples, 100 seeds and 42 fruits were analyzed; the latter being collected in Santo Antonio do Leverger - MT - Brazil, in 2011. To describe the morphology of the seedling, 100 seeds were germinated in two different environments. The araticum plant has a compound, multiple strobiliform, globose-subglobose and fleshy fruit, with average measures of 12.9 cm length, 13.5 cm width, 12.7 cm thickness, weight of 1,187.0 g and 99.2 seeds per fruit. The seeds are obovoid, hairless, smooth with a bony aspect and a pale brown color; they have an average of 17. 7 mm length, 10.8 mm width and 8.3 thickness. Epigeous and phanerocotylar germination begins about 148 days after sowing. All morphological data of araticum fruits, seeds and seedlings can be used to recognize the botanical family and, when associated to other features, to recognize the species in the field.

Physiological behaviour of Blepharocalyx salicifolius and Casearia decandra seeds on the tolerance to dehydration

The present work aimed to develop studies on the tolerance to dehydration of Blepharocalyx salicifolius and Casearia decandra seeds. In order to verify the effect of drying on the seeds, they were placed in desiccators containing a saline solution saturated with potassium acetate (23.5% RH) at temperature of 15 °C. After obtaining the desired moisture contents, the seeds were submitted to the germination, vigor, tetrazolium and electrical conductivity tests. It can be concluded that under slow drying conditions, the seeds of B. salicifolius and C. decandra were sensitive to moisture reduction of 29% to 25%, and lost viability at around 14% and 8% of moisture content, respectively. The physiological changes occurring during seed drying showed there was a decrease in viability and vigor and an increase in electrical conductivity values starting at 25% seed moisture content.