Marcadores moleculares para identificação de macroalgas marinhas do Filo Rhodophyta no litoral cearense

Abstract

Red algae are essentially marine organisms that occur from tropical regions all the way to polar regions. Molecular data applied to the study of these algae were obtained from the chloroplast genome, as well as from the mitochondria and the nucleus, and these data are very useful to stablish distinction among species and phylogeny of the group. In this work, we sequenced red macroalgae molecular markers aiming the identification and assessment of the intraspecies populational differences. We collected algae from Fortaleza (Farol beach and Meireles beach), Caucaia (Pacheco beach) and Paracuru (Pedra Rachada beach). Sampled organisms were preserved in CTAB and silica gel, formaldehyde and as exsiccates. The DNA extracted from the samples was used in PCRs with specific primers for each of the three molecular markers (UPA, rbcL and COI). PCR products were sequenced and the sequences processed in MEGA, aligned with MAFFT and phylogenetic trees using Neighbor-Joining were generated. 13 taxa were identified: Agardhiella subulata, Dichotomaria obtusata, Gelidium coarctatum, Gracilaria cornea, G. cervicornis, G. cuneata, G. hayi, G. intermedia, G. yoneshigueana, Gracilariopsis silvana, Hypnea musciformis, Meristotheca sp. e Solieria sp. The max intraspecific divergence observed was of 1.8% in H. musciformis. This work provided grand learning about the processes of acquisition and manipulation of molecular data marine red algae. However, it is necessary to complement it with traditional (morphological) identification methodologies and the continuous deepening of the algal studies, especially in the near shore zone.