| Popis: |
The brown seaweed Sargassum spp., locally known as “samò,” is subject to increasing overexploitation in the natural environment; thus, culturing the species for mass production is necessary. Understanding the required environmental factors is essential in the successful culture and mass production of this species. This study aims to determine the egg release and fertilization of Sargassum polycystum in response to the different environmental conditions that may influence its reproduction. Fertile thallus of S. polycystum was collected at Naawan, Misamis Oriental, Philippines in March 2018. Reproductive receptacles were excised and placed in Petri dishes and were exposed to varying environmental conditions under laboratory conditions. The experiments were conducted in triplicate Petri dishes per treatment. Percent (%) egg release and percent fertilization were observed for about 2 wk. Results showed that percent egg release and percent fertilization did not differ significantly across temperature ranges (20–30°C) and desiccation time (5–60 min). Receptacles treated with nutrients resulted in only ~ 45% egg release with a daily decrease of 10% towards the addition of AGP fertilizer. The highest % egg release (80%) was observed in the control treatment (no fertilizer). Percent egg release in receptacles subjected to 20–45 PSU showed no significant difference. This study suggests that the optimum condition for the release of eggs and subsequent fertilization can be achieved under ambient temperature, with no direct exposure to sunlight, no addition of fertilizer, and within the ambient salinity of 30–32 PSU. |
