On the efficacy of anAscophyllum-based, soluble extract in association with standard plant growth regulators on the micropropagation of the agarophyte,Gracilaria blodgettii, from seaweed farms located at the northern entrance of the Panama Canal

Gracilariaspp. (agarophytes) are cultivated by Panamanian communities to use directly as food and as important components of traditional medicines and remedies. These uses are part of the traditional culture of both the Guna Indians and the Afro-Antillean communities. One driving force to better understand the biology of the various species ofGracilariais their additional, commercial uses based on the agars they produce. In this study, we evaluated the effects of two commercial, soluble extract powders of the temperate, brown seaweedAscophyllum nodosum(i.e.,Ascophyllummarine plant extract powder-AMPEP), and one which had a boosted potassium level (designated as AMPEP K+). Each was evaluated for any micropropagation effects on the tropical red alga,Gracilaria blodgettii, in three independent experiments each of which lasted 45 days (the normal grow-out period). The phyco-stimulatory extracts were tested with and without association with standard plant growth regulators which are commonly used in micropropagation practices for higher plants. Growth was measured as a function of increased fresh weight and the number of newly emergent lateral shoots. This study demonstrated that vegetative propagules ofG. blodgettiitreated with AMPEP at 0.1 mg L(-1)provided significant contributions to the successful and sustainable supply of vegetative propagules (seedstock). We suggest that the costs and quality of seedstock production can be significantly reduced over traditional methods, thereby contributing to the establishment of much-needed, viable marine farming practices in the Panamanian Caribbean.