Banca de DEFESA: POLIANA MARIA TRINDADE ALVES

Uma banca de DEFESA de MESTRADO foi cadastrada pelo programa.
DISCENTE : POLIANA MARIA TRINDADE ALVES
DATA : 27/07/2018
HORA: 14:00
LOCAL: Sala PoP -Centro de Convivência da UFRN
TÍTULO:

Circadian rhythm of the flowering of Melocactus zehntneri: Who are your pontential visitors and pollinators?

PALAVRAS-CHAVES:

plant-nectarivore interaction, floral rewards, Melocactus zehntneri, resource sharing, Glossophaga soricina, Lionycteris spurelli, Lonchophylla sp. and Xeronycteris vieirai

PÁGINAS: 38
GRANDE ÁREA: Ciências Biológicas
ÁREA: Ecologia
RESUMO:

The resources in the Caatinga vary with the seasonality of the region and are less abundant in the dry season. In this period few plants are in the flouring period, among them are some Cactaceae, there are few resources for the nectarívoros. For this reason, opportunistic pollinators can visit them and / or steal the nectar. The work will describe the circadian cycle, the nectar production and pattern of secretion, consumption and visitation in Melocactus zehntneri, seeking possible explanations about the interactions between this cactus and bats (Glossophaga soricina, Lionycteris spurelli, Lonchophylla sp. and Xeronycteris vieirai) in the Caatinga of Lajes do Cabugi / RN. Recently, a parallel study has reported that these bats are visiting the cactus because large amount of pollen of the species was found in their hairs or feces. But their flowers do not indicate signs of chiropterophily, therefore data were collected in the field and an experiment was carried out to investigate the existence of floral rewards and responses, in the circadian cycle and in the pattern of nectar secretion, related to this interaction. The volume and concentration of sugar in the nectar decreased after 5:30 pm, but it continues with quality to compensate nocturnal pollinators that begin to forage at that time, such as small bats that living in Caatinga. The hummingbirds are pollinators more efficient of M. zehntneri, and probably they’re sharing the nectar with other floral visitors, including the bats of the region. There is a change in the pattern of nectar secretion before and after at 17:30 pm, which may be associated to the same floral visitors of this plant. This fact may increase the genetic variability in the population of the cactus, since it would also benefit other floral visitors besides the hummingbird that shows a very territorialist behavior. In addition, bats may be using the nectar of this plant as an alternative source of energy in the dry period of the Caatinga, because the resources are scarcer.

MEMBROS DA BANCA:
Externo ao Programa - 1813882 - ALICE DE MORAES CALVENTE VERSIEUX
Presidente - 1718346 - EDUARDO MARTINS VENTICINQUE
Externo à Instituição - JOSÉ EDUARDO ZAIA - FATEC