International Journal of Aquaculture, 2024, Vol.14, No.3, 112-125 http://www.aquapublisher.com/index.php/ija 117 biostimulants has been demonstrated to increase the growth rate and yield of tomato plants (Supraja et al., 2020). Additionally, algae play a crucial role in bioremediation, where they are used to treat wastewater and capture carbon dioxide. Algal-based systems can efficiently remove nutrients and pollutants from wastewater while simultaneously producing biomass that can be used for bioenergy or other value-added products (Choudhary et al., 2020). The sustainable utilization of algal germplasm spans various sectors, including biotechnology, pharmaceuticals, nutraceuticals, agriculture, and environmental management. By leveraging the unique properties and diverse applications of algae, it is possible to develop innovative solutions that contribute to sustainability and address global challenges. 5 Case Studies in Conservation and Utilization 5.1 Successful conservation programs One of the notable conservation programs for algal germplasm is the establishment of germplasm cryopreservation techniques, particularly for macroalgae. A review by Yang et al. (2021) highlights the development and implementation of cryopreservation protocols for various macroalgal species (Table 1). These techniques include programmable controlled cooling and vitrification, which have been shown to effectively preserve the genetic material of algae at ultra-low temperatures, ensuring long-term viability and genetic stability. This approach is crucial for both aquaculture breeding programs and the conservation of natural biodiversity. Yang et al. (2021) systematically reviewed research since 1964, summarizing the cryopreservation methods for 33 species of seaweeds and the factors affecting survival rates after thawing. The study indicates that commonly preserved materials include haploid or diploid algal bodies, spores, and gametes, with dimethyl sulfoxide (DMSO) being the primary cryoprotectant used. The two main cooling methods highlighted are programmable controlled-rate cooling and vitrification. The research emphasizes optimizing various steps in the preservation process, such as the selection of cryoprotectants, packaging, cooling rates, and thawing methods, to enhance survival rates post-thaw. Table 1 Research progress in cryopreservation of different seaweed species (Adapted from Yang et al., 2021) Species Cryoprotectant Cooling method Post-thaw viability Ulva pertusa DMSO, Glycerol, Sucrose Controlled-rate cooling 50% Ulva intestinalis Glycerol, NaCl, Ethylene glycol Controlled-rate cooling 60% Neopyropia tenera DMSO, Diglycerol Vitrification 80% Saccharina japonica DMSO, Glycerol Controlled-rate cooling 70% Gracilaria corticata DMSO Controlled-rate cooling 65% Hypnea musciformis Glycerol Vitrification 55% Ulva prolifera Glycerol Controlled-rate cooling 90% Ectocarpus fasciculatus Glycerol Controlled-rate cooling 75% Table 1 summarizes the research progress in the cryopreservation of different seaweed species, covering studies from 1960 to the present. The table lists the seaweed species studied, the cryoprotectants used, the cooling methods, and the survival rates after thawing. The subjects include green, brown, and red algae, with the primary cryoprotectants used being dimethyl sulfoxide (DMSO), glycerol, and sucrose. Cooling methods include programmable controlled-rate cooling and vitrification. The survival rates presented in the table vary depending on the species and the methods used, demonstrating significant differences in freeze tolerance and survival rates among different species under the same cryoprotectant and cooling rate conditions.
RkJQdWJsaXNoZXIy MjQ4ODYzNA==