Valéria Cress Gelli1, Marcelo Ricardo de Souza1, Estela Maria Plastino2, Nair S. Yokoya3
1Instituto de Pesca, Agência Paulista de Tecnologia dos Agronegócios, Secretaria da Agricultura e Abastecimento do Estado de São Paulo. Estrada do Professor Joaquim Lauro Monte Claro, 2275, Ubatuba, SP, 11688-102, Brazil
2Departamento de Botânica, Instituto de Biociências, Universidade de São Paulo, Rua do Matão 277, 05508-090, São Paulo, SP, Brazil
3Centro de Conservação da Biodiversidade, Instituto de Pesquisas Ambientais, Av. Miguel Estéfano 3687, Água Funda, São Paulo, SP, 04301-902, Brazil
The process of domestication of the seaweed Kappaphycus alvarezii (Doty) L.M. Liao has been taking place since 1995 and 1996 with the introduction of a brown tetrasporophyte and a pale brown gametophyte, respectively, in the experimental marine farm of the Fisheries Institute, Ubatuba Bay, São Paulo State, Brazil. From these initial strains, spontaneous strains were generated with different colors. From 2013 to 2022, the occurrence of spontaneous color strains and data of temperature, salinity and water transparency were recorded on the cultivation site. For data analysis, binary logistic regression model was used to identify the significant associations between the presence of spontaneous generation of new strains of K. alvarezii (outcome variable) and abiotic data (predictors), and ROC curve was used to investigate the probability of giving rise to new strains. It was observed the appearance of 13 new color strains. The appearance of new brown strains was not observed in this study. Results showed that temperature was significant (p-value 0.025) for generation of new color strains. According to temperature range used in the model, the probabilities to originate a new strain was 7.6% in temperature of 15oC and 0.01% at 33ºC. The occurrence of new strains of K. alvarezii may contribute to the selection of new cultivars for local mariculture. Financial supports: CNPq, FAPESP.