Fenologia, germinabilidade e qualidade de sementes de Alibertia edulis Rich. e Lafoensia pacari St. Hill

Abstract

Alibertia edulis Rich and Lafoensia pacari St. Hill. are typical species of Cerrado, much appreciated by the medicinal potential, popularly known as marmalade-ball and manva-brava respectively. The objective of this work was to follow the phenological cycle of the two species in two distinct areas, as well as to study the germinability and quality of A. edulis seeds as a function of storage and temperature and to evaluate the biometry and the effect of color and size of the seeds in the germination of L. pacari. Phenological studies were carried out in a property located 15 km from the municipality of Cuiabá-MT. The observations were made for a period of 24 months, every two weeks, in two areas with distinct phytophysiognomies (Cerrado restricted sense and Cerradão), using the Fournier index. In the germinability studies of A. edulis, the seeds were stored in a refrigerated chamber for 0, 6, 12, 18 and 24 months. In each storage period the water content,% of germination and% of emergence were determined. The temperatures evaluated were the constants of 15, 20, 25, 30 and 35øC and alternates of 25-15 and 25-20øC. The seeds of L. pacari were evaluated for biometric characteristics by measuring the length, width, thickness, mass of the fresh matter of fruits and seeds and the number of seeds per fruit. In the germination evaluations, the seeds were visually separated by coloration, in light and dark, and then separated and sorted by size into small, medium and large seeds. Phenophases showed a significant correlation with some environmental variables for the two species studied. A. edulis is a perennial species, with sprouting and reproductive phenotypes influenced by precipitation. The senescence of the leaves of L. pacari is seasonal in the dry period, with sprouting occurring in the rainy season. Its flowering correlates negatively with RH and precipitation, while fruiting occurs at the beginning of the rains. A. edulis seeds can be stored in a refrigerated chamber for up to six months, with a water content of 11%, maintaining the capacity to germinate and form normal seedlings above 90%. The vigor of the seedlings of A. edulis was favored with storage, mainly for the period of twelve months. Temperatures of 25 and 30 ° C are the most suitable for the germination test, but for the initial development of the seedlings the temperature of 25 ° C is the most adequate. The biometric characteristics of the seeds of L. pacari present greater variation than the fruits. Large, light-colored seeds show a higher percentage of germination.