Genetic differentiation and distribution of Pyropia acanthophora (Bangiales, Rhodophyta) in the Philippines

Kim

et al. 2023

Plants

Part of the Indo-Chinese peninsula and located on the northwest edge of the Coral Triangle in the South China Sea, the Vietnamese coastal zone is home to a wealthy marine biodiversity associated with the regional geological setting and history, which supports a large number of marine ecosystems along a subtropical to tropical gradient. The diversity of coastal benthic marine primary producers is also a key biological factor supporting marine biological diversity. The present review provides: (1) an updated checklist of the Vietnamese marine flora, (2) a review of molecular-assisted alpha taxonomic efforts, (3) an analysis of marine floral biodiversity spatial distribution nationally and regionally (South China Sea), (4) a review of the impact of anthropogenic and environmental stressors on the Vietnamese marine flora, and (5) the efforts developed in the last decade for its conservation. Based on the studies conducted since 2013 and the nomenclatural changes that occurred during this period, an updated checklist of benthic marine algae and seagrasses consisted in a new total of 878 species, including 439 Rhodophyta, 156 Ochrophyta, 196 Chlorophyta, 87 Cyanobacteria, and 15 phanerogam seagrasses. This update contains 54 new records and 5 new species of macroalgae. The fairly poor number of new records and new species identified in the last 10 years in a “mega-diverse” country can be largely attributed to the limited efforts in exploring algal biodiversity and the limited use of genetic tools, with only 25.4% (15 species) of these new records and species made based on molecular-assisted alpha taxonomy. The South Central Coast supports the highest species diversity of marine algae, which coincides with the largest density of coral reefs along the Vietnamese coast. Vietnam holds in the South China Sea one of the richest marine floras, imputable to the country’s geographical, geological, and climatic settings. However, Vietnam marine floral biodiversity is under critical threats examined here, and current efforts are insufficient for its conservation. A methodical molecular-assisted re-examination of Vietnam marine floral biodiversity is urgently needed, complemented with in-depth investigations of the main threats targeting marine flora and vulnerable taxa, and finally, conservation measures should be urgently implemented.

Section: Intraspecific Genetic Diversity Studiesmentioning

confidence: 99%

Marine Floral Biodiversity, Threats, and Conservation in Vietnam: An Updated Review

Kim

et al. 2023

Plants

“…Prior to the genomic era, various studies analyzed the genetic diversity of Pyropia species. For example, studies used the methods based on simple sequence repeat [8,9], DNA sequencing of several genes [10][11][12][13][14][15][16][17][18][19][20][21][22][23][24][25][26][27][28], amplified fragment length polymorphism [29,30], and polymerase chain reaction-restriction fragment length polymorphism [31]. These previous studies analyzed small regions of the genome.…”

Section: Introductionmentioning

confidence: 99%

Genomic diversity of 39 samples of Pyropia species grown in Japan

et al. 2021

Some Pyropia species, such as nori (P. yezoensis), are important marine crops. We conducted a phylogenetic analysis of 39 samples of Pyropia species grown in Japan using organellar genome sequences. A comparison of the chloroplast DNA sequences with those from China showed a clear genetic separation between Japanese and Chinese P. yezoensis. Conversely, comparing the mitochondrial DNA sequences did not separate Japanese and Chinese P. yezoensis. Analysis of organellar genomes showed that the genetic diversity of Japanese P. yezoensis used in this study is lower than that of Chinese wild P. yezoensis. To analyze the genetic relationships between samples of Japanese Pyropia, we used whole-genome resequencing to analyze their nuclear genomes. In the offspring resulting from cross-breeding between P. yezoensis and P. tenera, nearly 90% of the genotypes analyzed by mapping were explained by the presence of different chromosomes originating from two different parental species. Although the genetic diversity of Japanese P. yezoensis is low, analysis of nuclear genomes genetically separated each sample. Samples isolated from the sea were often genetically similar to those being farmed. Study of genetic heterogeneity of samples within a single aquaculture strain of P. yezoensis showed that samples were divided into two groups and the samples with frequent abnormal budding formed a single, genetically similar group. The results of this study will be useful for breeding and the conservation of Pyropia species.

Squalen Bull. Marine Fisheries Postharvest Biotech.

“…The COI marker is widely used for Kappaphycus identification for taxonomic purposes and phylogenetic relationships (Tan, Lim, & Phang, 2013). The COI marker of red algae for this gene is very robust and it has greater variation than the COX2-COX2 spacer in eucheumatoids (Dumilag et al, 2018;Dumilag & Aguinaldo, 2017). Identification of Kappaphycus using COI has been performed in several countries: Hawaii (Conklin, Kurihara, & Sherwood, 2009), Malaysia (Tan, Lim, & Phang, 2013), and the Philipppines (Dumilag, Orosco, & Lluisma, 2016).…”

Section: Introductionmentioning

confidence: 99%

Genetic Diversity Analysis of Cultivated Kappaphycus in Indonesian Seaweed Farms using COI Gene

Ratnawati¹,

Simatupang²,

Pong-Masak³

et al. 2020

Indonesia is a major player in the aquaculture of red algae, especially carrageenan producing ‘eucheumatoids’ such as Kappaphycus and Eucheuma. However, many current trade names do not reflect the evolutionary species and updated taxonomy, this is especially the case for eucheumatoid seaweeds that are highly variable in morphology and pigmentation. Genetic variation is also not known for the cultivated eucheumatoids in Indonesia. Therefore, this study aimed to determine the species and the level of genetic variation within species of cultivated eucheumatoids from various farms across Indonesia, spanning 150-1500 km, using the DNA barcoding method. Samples of seaweed were randomly collected at 14 farmed locations between April 2017 and May 2018. For this study the 5-prime end (~ 600 bp) of the mitochondrial-encoded cytochrome oxidase subunit one (COI) was amplified and sequenced. Morphological examination showed that the samples were quite variable in branching pattern and color. All samples collected from farms with floating line cultivation were identified based on COI sequences as Kappaphycus alvarezii and showed no variation in the COI gene. One farm sample with bottom-line cultivation was identified as K. striatus. The low genetic variation is in contrast to the phenotypic variation of samples, indicating that variation and phenotypic responses to environments is still found in samples with implications for growth rates and carrageenan yield and quality. Information about the genetic variation in stocks is important base knowledge for maintaining, expanding and continuing seaweed aquaculture.