Proposal of a fertility index of Hypnea for ecophysiological studies

Abstract

Few studies of natural populations of the red algae Hypnea musciformis have been conducted. To enhance our knowledge, it would be helpful to define methodologies that explore the species' adaptability to different environments and seasons. Tetrasporophyte is the most frequent reproductive stage in this species. A case study of 2 populations in the Brazilian tropics allowed us to define a fertility index based on the meiotic count of tetrasporangia. Significant differences were found in the production of tetrasporangia among microhabitats and between the dry and rainy seasons. The analysis of this index in red algae may constitute an important tool for understanding the biology and ecology of this algal group.