Germinação de sementes e aspectos etnobotânicos de Melocactus violaceus Pfeiff no estado de Sergipe

Abstract

The Melocactus violaceus Pfeiff is a specie belonging to the Cactaceae family, endemic in Brazil and typical of the Restinga ecosystem on the Brazilian coast. Popularly known as the head of the monk, in Sergipe is one of the most recorded species in the Restinga of the state, but its status is vulnerable (VU) according to international criteria of Union for Nature Conservation due to the strong utilitarianism and fragmentation of its species occurs. Allied to these factors is the vegetative phase of the very long species, a decade until it begins to produce fruits, which further aggravates its vulnerability. The objective of this work was to identify the Melocactus violaceus in its habitat and its importance in the state of Sergipe through bibliographic review, germination tests in substrate and in vitro aiming the production of seedlings, and to develop ethnobotanical study. For the germination tests, the evaluated variables were the germination speed index (IVG) and the percentage of germination. The experiments of germination in substrate were carried out in laboratory and greenhouse. The substrate used was washed sand and 1: 1 vegetable soil with seeds previously soaked in different time intervals. In the laboratory, there were significant differences in IVG values and percentage of germination. In the greenhouse, there was a significant difference only for the IVG variable. For in vitro germination, the basic medium used was composed of the Murashige & Skoog salts formulation. This experiment was composed of two imbibition treatments: seeds imbibed in distilled water (T1) and seeds embedded in gibberellin (T2) at concentrations of 0; 0.5; 1.0; 2.0 and 4.0 mgL-1. In the results obtained in treatment 1 there were significant differences in Germination Percentage and IVG, however, in treatment 2 there was a significant difference only in IVG according to the Scott-Knott test at 5% significance. The substrate germination treatments for the M. violaceus seeds in the greenhouse showed better results in the germination percentage and in the IVG, with periods of imbibition of more than 30 minutes. The treatments with germination in vitro were efficient and reached more than 40% of germinated seeds, but in the treatments with gibberellin the evaluated concentrations of the phytorregulator did not present significant difference on the percentage of germination. The ethnobotanical study was developed with 60 people in the County of Pacatuba, Pirambu and Aracaju, on the knowledge and uses of M. violaceus. In each municipality, 20 people were interviewed through a semi-structured road map. The profiles of the interviewed population, the way of knowledge was divided in the communities, as well as the categories of use were identified. The categories of use identified were ornamental, medicinal, mystical and food.