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ANNEXES (Contd.)

Annex III


1.1 Taxonomy and ecology

BangladeshNo report of Gracilaria spp., but it is possible that the survey done may have been limited to riverine areas. More detailed surveys towards the outer part of the bay will probably reveal some Gracilaria spp.
ChinaScientific names appear to be correctly applied for three species - G. lemaneiformis, G. tenuistipitata and G. asiatica. Taxonomic description complete for three species. Gracilaria sp. needs verification, more materials and samples are needed.
 Ecological data:Complete except for depth and habitat (exposed/not exposed during low tides).
IndiaScientific names appear to be correctly applied, except for G. crassa. Taxonomic descriptions lack information on male reproductive structures.
 Ecological data:Complete except for depth and habitat (intertidal/subtidal or exposed/not exposed during low tides.
IndonesiaScientific names are correctly applied for G. eucheumoides and G. salicornia, but G. edulis, G. lemaneiformis and Gracilaria spp. need verification. More materials are needed.
 Ecological data:Lacks information on habitat, type of substrate, whether intertidal or subtidal and exposed or not during low tides.
MalaysiaTaxonomic description very incomplete. Needs taxonomic description of each species. The scientific names applied have to be verified, especially G. changii and Gracilaria sp.
 Ecological data:Notes are incomplete and should be summarised in a table.
MyanmarTaxonomic description complete but the format should conform to the regular format used in taxonomic studies. The identity of G. verrucosa should be re-evaluated as this species is not found in Asia. G. crassa should be changed to G. salicornia.
 Ecological data:Should be condensed in the table “Summary.....”.
PhilippinesNo taxonomic description of the species which should be a major part of the report. At least the species analysed for agar should be included. The species in the data sheets are all Gracilaria sp.
ThailandTaxonomic description present but incomplete. Only gross morphology of the genus is described, a more detailed description is needed. The scientific names applied are probably correct but the lack of important taxonomic characters in the description is a source of doubt.
 Ecological data:Lacking some ecological notes on habitat, abundance and reproductive status.
VietnamTaxonomic notes available but the binomids should be placed at the start of the description. The species need to be verified especially in the absence of note of the male structures.
 Ecological data:Lack of data on habitat, type of substrate and depth.

1.2 Processing technology of Gracilaria

ChinaComplete analysis of agar quality in almost all of the essential parameters. In addition, different techniques of agar extraction are also reviewed and compared. Good quality agar is mostly from Gracilaria tenuistipitata collected from June to September. Although it should be noted that the values of agar content are very high and need to be verified. Due to its long experience in seaweed processing, China has a leading roles in the seaweed industry. With this expertise, they are able to help other NACA member countries to develop seaweed resources, as well as the analysis of seaweed products.
Culture of Gracilaria:
i.Candidates for culture:
G. asiatica
G. lemaneiformis
G. hainanensis
G. tenuistipitata var. liui
All of these species, especially G. asiatica and G. tenuistipitata var. liui have been studied in detail with respect to their reproduction, ecological characteristics and culture methods, as well as their agar contents and qualities.
ii.Culture methods
Intertidal culture - Suitable for all candidate species.
Floating culture - Suitable for G. asiatica, G. lemaneiformis and G. hainanensis.
Pond culture - Suitable for G. tenuistipitata var. liui because it is hard to find its sexual organs and tetrasporangia over whole seasons. It is not like G. asiatica, therefore the thalli would decay after releasing the spores and gametes.
iii.Other aspects
Genetic studies. Use the experience gained on seaweed genetic studies of Laminaria and Porphyra to introduce and select new varieties with fast growth rates and higher agar quality.
Tissue culture. Develop new techniques to improve methods of spore collection.
IndiaMost of the agarophyte seaweed resources in India are G. edulis with low gel strength. As G. edulis is the major seaweed resource attempts should be made to improve agar extraction techniques.
i.Candidates for culture:
G. edulis
G. tenuistipitata
The natural resource of G. edulis is abundant and the species is adapted to the local climate and other natural conditions, it is therefore much easier to promote local seaweed farming industries. The species, G. tenuistipitata var. liui is not mentioned in the country report.
ii.Culture methods
Intertidal culture and pond culture are good for Indian natural conditions. Particularly using polyculture techniques to farm seaweed and shrimp or finfish together.
iii.Suggested projects
Intensify studies on taxonomy and ecology of Gracilaria spp. and conduct suitable extension methods for culture.
IndonesiaFrom the results of analysis of agar quality, there are at least two species of Gracilaria which give good agar quality in terms of gel strength, G. edulis and G. lemaneiformis. Moreover, most of the species have low gelling temperatures, which is an important characteristic of agar quality preferred for applications in microbiological mediums. There is an opportunity to develop high-value agars. Further study should be carried out on process development as well as development of the high-value agar product. Improvement of the agar extraction process should be studied to increase agar yields and clarity.
MalaysiaThe method of agar extraction in the study was done without alkali pre-treatment and with simple processing equipment which was provided by NACA after the first workshop. However, the quality of selected agar samples showed relatively high gel strength. There is a high possibility of the process development for agar extraction to obtain an agar product with high gel strength. The support of equipment as well as training of the personnel is recommended for the development of seaweed processing technology in Malaysia since local seaweed resources are readily available and there is potential for good quality agar.
MyanmarThe local available species which give a similar gel quality are G. verrucosa, G. edulis and G. crassa. More development in both processing techniques and product development is recommended. More research work is needed. Support for equipment and well trained personnel should be provided.
Myanmar gave descriptions of 7 species: G. crassa; G. edulis; G. eucheumoides; G. foliifera; G. millardetii; G. textorii; and G. verrucosa. They also reported agar analysis from species mentioned above, except G. eucheumoides. However, ecological data was obtained from only 2 species, G. edulis and G. foliifera. Culture experiments showed that G. edulis can be grown eight months of the year with monthly harvests from April to September, suggesting commercial potential. It also grows well in the natural conditions and is suitable for culture both in inland ponds and in the open seas.
PhilippinesFrom the results of agar extraction and analysis, there are several species of Gracilaria which give good agar quality, such as G. heteroclada, G. tenuistipitata and G. firma. With high agar yields of 16–20 %, these Gracilaria species will be important raw material sources for agar production. Systematic and well-developed experience in analysis of agar is the most important resource to facilitate the development of the agar industry in the Philippines. Funding support would aid the progress of the development of the seaweed industry in the Philippines.
General comments on report.
1.Supply taxonomic description of species
2.Supply data on: ecological parameters; gelling temperature; seasonally in reproductive states; and abundance
3.Species recommended for farming include only three species G. heteroclada, G. tenuistipitata and G. firma.
ThailandThe Gracilaria which gave the best quality agar were G. fisheri and G. tenuistipitata which grows naturally in the southern coastal area of the country. However, the availability of the seaweed raw material is quite limited in Thailand. Incentives to farm seaweed are needed for the local coastal people to increase production. The seaweed processing industry is promoted by the Royal Thai government, for instance by the reduction of the import tax for seaweed raw materials and research funding for seaweed production and processing. The initiative of the seaweed processing industry needs to be promoted in terms of its economic, social and environmental benefits.
Thailand reported 7 species collected from eastern and southern Thailand: Trat, Songkhla and Pattani. They are G. changii, G. edulis, G. firma, G. fisheri, G. irregularis, G. salicornia, and G. tenuistipitata. Only 5 species, one sample each were used for agar analysis. The results show that G. fisheri and G. tenuistipitata were the most valuable followed closely by G. firma. In contrast, G. salicornia and G. changii gave lower yields and low quality agar. It was recommended that G. fisheri and G. tenuistipitata be further studied as useful resources for agar production.
VietnamGracilaria verrucosa gave high yields and high gel strength of agar. Improvement of the agar extraction method should be further studied with international support. Co-operation among local institutions to strengthen personnel and resource ability are recommended for the development of the seaweed processing industry in Vietnam.
The resource persons questioned why this study was limited to a small region in the north of the country and the exact method of extraction. There was also no data about ecological parameters of the 3 strains of G. verrucosa.

1.3 General comments on the country reports

Vietnam and Indonesia


1.4 Recommendations (Thailand, Myanmar and other countries)


Quality of agar according to Japanese (Chandrkrachang and Chinadit, 1988)

GradeMean gel strength (g/cm2)Species nameMean Yield of Agar (%)No of countries observations
Special grade agar608G. asiatica*48.21
570G. lemaneiformis*28.482
892G. heteroclada20.051
649G. firma182
850G. eucheumoides171
758G. fisheri12.81
Grade I578Gracilaria sp. *51.31
584G. tenuistipitata *22.24
356G. salicornia113
565Gracilaria sp.10.11
Grade II278G. blodgettii26.51
290G. chorda21.51
257G. changii20.03
292G. verrucosa202
250G. fastigiata19.31
280G. edulis o15.33
Grade III34.4G. corticata var. corticata o22.41
-Gracilaria sp.22.41
47.2G. corticata var cylindrica o19.81
128G. bursa-pastoris15.71
85G. textorii151
76G. millardetii14.51
64.5G. foliifera13.91
62.4G. crassao12.12

* These results take into account the data from China that give % yield of agar about 4 times higher than the other countries.

o These results take into account the data from India that give gel strengths ten times higher than the other countries.

+ The countries involved are Bangladesh, China, India, Indonesia, Malaysia, Myanmar, Philippines, Thailand and Vietnam.


Table 3.1: China
Table 3.2: India
Table 3.3: Indonesia
Table 3.4: Malaysia
Table 3.5: Myanmar
Table 3.6: Philippines
Table 3.7: Thailand
Table 3.8: Vietnam

3.1 Summary of Results on Gracilaria Species in China

AbundanceSalinity (ppt)Temp (°C)SubstrateDepth (cm)Rep. StageYield (%)Gel strength (g/cm2)Gelling Temp. (°C)Melting Temp. (°C)Method of extractionCode (Table IV, Country Report)
G. lemaneiformis1-6-94+28.6–31.023–26Rocky Y46.4848 93.55%NaOH1AQuingdao
G. lemaneiformis27-8-94+  Rocky Y47.6872 91.0"1BQuingdao
G. asiatica1-6-94+28.6–31.023–26Rocky-sand  44.1682 80.0"2AQuingdao
G. asiatica24-7-94+  Rocky-sand Y52.3534 92.0"2BQuingdao
G. tenuistipitata26-6-94+++28.530.2Muddy-sand Y38.2482 92.5"3AShanyao
G. tenuistipitata31-7-94+32.331.0Muddy-sand  44.7634 95.0"3BShanyao
G. tenuistipitata3-9-94+23.029.0Muddy-sand  35.01001 103.2"3CShanyao
Gracilaria sp.17-7-94+++28.337–39Muddy-sand V.P.48.7609 96.8"4BDongshan Island
Gracilaria sp.17-7-94+++24.237–39Muddy-sand V.P.57.5578 93.0"4CDongshan Island
Gracilaria sp.20-8-94+++23.128–29Muddy-sand V.P.47.6549 94.0"4DDongshan Island
G. tenuistipitata v. liui26-6-94+++11.734.7Muddy-sand V.P.49.7363 93.5"5AQuiantou
G. tenuistipitata15-6-94+++20.429Muddy-sand V.P.38.0720 99.2"5BDiancheng
G. tenuistipitata18-8-94 027.2Muddy-sand V.P.33.3446 97.2"5CDiancheng
G. tenuistipitata var. liui16.-8-94+++7.33-8.6229.2-31.0Sandy-mud V.P.44.9373 92.8"7ARongshan
G. tenuistipitata var. liui12-6-94+22.133–36Muddy V.P.42.8360 94.5"8ABeihai

Y=Reproductive structures present
V.P.=Vegetative propagation.

3.2 Summary of Results on Gracilaria Species in India

AbundanceSalinity (ppt)Temp (°C)SubstrateDepthRep StageYield (%)Gel strength (g/cm2)Gelling Temp. (oC)Melting Temp. (oC)Method of extraction 
G. edulis4-6-92+++31.530Sand/coral Y1734.69 955% NaOH 
G. edulis14-8-92+35.8428.4Sand/coral N15.462.69 95" 
G. edulis29-9-92+34.6229.2Sand/coral Y20.858.69 94" 
G. edulis24-12-92+32.4627.4Sand/coral N13.634.69 95" 
G. edulis6-2-93+++34.5626.0Sand/coral Y16.431.69 95  
G. edulis23-4-93+35.8632.4Sand/coral Y10.658.69 94  
G. edulis28-5-94+++30.829.6Sand/coral Y14.852.69 97  
G. edulis24-6-94+++35.227.6Sand/coral Y14.252.69 98  
G. edulis12-7-94+++34.627.4Sand/coral Y19.4113.69 98  
G. edulis10-8-94+++35.628.6Sand/coral Y 93.69 98  
G. edulis6-9-94+++34.629.2Sand/coral Y19.898.69 98  
G. corticata var. corticata.27-5-94+++32.429.4Rocky Y18.832.69 98" 
G. corticata var. cylindrica23-6-94+++35.227.6Rocky Y30.844.69 98  
G. crassa23-7-94+++34.627.6Rocky Y1734.62 98  
G. corticata var. corticata24-8-94+++34.828.4Rocky Y25.038.69 985% NaOH 
G. corticata var. corticata15-9-94+++34.2629.6Rocky Y15.831.69 95" 
G. corticata var. cylindrica28-5-94+++30.829.6Sand/rock Y18.436.69 98" 
G. corticata var. cylindrica24-6-94+++31.227.6Sand/rock Y24.665.69 98" 
G. corticata var. cylindrica12-7-94+++34.627.4Sand/rock Y25.258.69 98" 
G. corticata var. cylindrica10-8-94+++35.628.4Sand/rock Y14.836.69 98" 
G. corticata var. cylindrica6-9-94+++34.6228.6Sand/rock Y20.840.60 98" 
G. crassa27-5-94+++32.429.4Stone pieces Y5.628.69 985% NaOH 
G. crassa29-6-94+++33.627.8Stone pieces Y5.427.69 98" 
G. crassa12-7-94+++33.828.2Stone pieces Y7.828.69 98" 
G. crassa10-8-94+++35.428.4Stone pieces Y5.129.69 98" 
G. crassa7-9-94+++34.4228.8Stone pieces Y6.229.69 98" 

3.3 Summary of Results on Gracilaria Species in Indonesia

AbundanceSalinity (ppt)Temp (°C)SubstrateDepth (cm)Rep StageYield (%)Gel strength (g/cm2)Gelling Temp. (°C)Melting Temp. (°C)Method of extraction 
G. edulis20-9-92++2829   8.136103668 SW 01
G. edulis8-10-92+++2929   13.618403990 SW 03
G. edulis15-6-93+++2928   15.775753279 SW 10
G. lemaneiformis20-9-94+++2829   9.968803485 SW 02
Gracilaria sp.9-10-92++2929   8.187802886 SW 04
Gracilaria sp.4-6-93+3328   12.125502889 SW 09
G. saliconia21-5-93++3128   5.475803275 SW 05
G. saliconia4-6-93+3328   11.076253172 SW 08
G. eucheumoides21-5-93+3128   16.998502932 SW 06

3.4 Summary of Results on Gracilaria Species in Malaysia

AbundanceSalinity (ppt)Temp (°C)SubstrateDepth (m)Rep StageYield (%)Gel strength (g/cm2)Gelling Temp. (°C)Melting Temp. (°C)Method of extraction
G. changii00113-5-92 2828   41.7   Non alc treat 
G. changii00228-5-92 3228 4m 39   "T = 90 cm
G. changii0039-7-92 3228 4m 35.8   "T = 85 cm
G. changii0049-9-92 3230 1.5m 30.5   "T=115cm
Hypnea sp.0059-9-92 2829 1.5m 13.5   "T=115cm
G. changii00624-4-93 28–3228–30sandy/muddy  20   "Sheltered, not exp.
G. fastigiata00724-4-93 3029 2.5m 15.889  "Sheltered, exp. (T=28 cm)
G. changii00814-5-93 28–3228–30 3.8m 25.4174  "Sheltered, not exp. (T=80 cm)
Gracilaria sp.00914-4-94   muddy  20.4   "Sheltered, exp.
Gracilaria sp.01027-7-94   muddy  24.4   "Sheltered, exp.
G. changii01117-9-94  28–30shrimp pond  25.2   "Sheltered, not exp.
G. changii0128-10-94   shrimp pond  22.1   "Sheltered, not exp.

Key: exp. = exposed at low tide.

not exp.: = not exposed at low tide. T = turbidity

3.5 Summary of Results on Gracilaria Species in Myanmar

SpeciesDateAbundanceSalinity (ppt)Temp (°C)SubstrateDepth (cm)Rep StageYield (%)Gel strength (g/cm2)Gelling Temp. (oC)Melting Temp. (°C)Method of extractionCode: NACA-
G. verrucosa       9–2262–12027–4052–702–6%NaOH001Rakhine/ Thanithari
G. edulis       10–2260–12027–3952–73"002Rakhine/ Thanithari
G. crassa       12–2170–12028–4055–73"003Rakhine/ Thanithari
G.foliifera       11–1960–9818–3950–82"004Rakhine/ Thanithari
G. millardetii.       10–1960–9229–3950–80"005Rakhine/ Thanithari
G. textorii       11–1960–11027–3952–73"006Rakhine/ Thanithari
G. edulis23-8-92Dominant-26.0Rocky10-18.2292.51 64–69 wildMushwe-key, Rakhine 9/92
G. edulis24-11-92Dominant-18.87polythene rope0–100-18.87116.5 45–62 cultured3/92.
Mushwe-key, Rakhine
G.foliifera18-2-92Dominant-12.85Rockyinter-tidal-12.8550.07 73–74 wild1/93. Martin Point, Rakhine
G. edulis18-2-92Dominant-22.18Rockyinter-tidal-22.18116.91 68–71 wild2/93 Martin Point, Rakhine

3.6 Summary of results on Gracilaria species in the Philippines

AbundanceSalinity (ppt)Temp (°C)HabitatDepth (cm)Rep StageYield (%)Gel strength (g/cm2)Gelling Temp. (°C)Melting Temp. (°C)Method of extractionRemarks
% SO42-
G.fastigiata ++25–3525–35open reef flat Sandy/rocky not?19.24250-795%NaOH3.28
G. saliconia +25–3525–35open reef flat Sandy/rocky c.c.20.07287-805%NaOH1.86
G. changii ++2534open reef flat Coral c.c.20.67583 865%NaOH0.56
G. tenuistipitata ++10–2525–33Brackish. Sandy-mud c.c16.18726 885%NaOH1.26
G.firma +++25–3525–35Mangrove Sandy-mud c.c (nov)17.61606 895%NaOH0.22
G. heteroclada ++10–2525–33Brackish pond -mud. n.o.20.05892 925%NaOH0.45

Key: n.o = not observed;

c.c = cystocarpa

3.7 Summary of results on Gracilaria species in Thailand

AbundanceSalinity (PPOTemp (°C)SubstrateDepth (cm)Rep StageYield (%)Gel strength (g/cm2)Gelling Temp. (°C)Melting Temp. (°C)Method of extractionCode: NACA-
G.firma28-4-93 3134Sandy-mud- --  3%NaOH001Trat
G. changii28-4-93 3337Sandy-mudexposed --  "002Trat
G. irregularis28-4-93 3337Sandy-mudexposed --  "003Trat
G. edulis28-4-93 3337Sandy-mud10–20 --  "004Trat
G. salicornia28-4-93 3134Sandy-mud30–50 --  "005Trat
G. salicornia8-6-93 --Sandy-mud30–50 4.75180 88"006Trat
G. changii8-6-93 32-Sandy-mud-F9.50190 90"007Trat
G. firma4-4-94 33.536Sandy-mud30F19.96692 93"008Songkhla
G.fisheri21-8-94 11-Muddy sand100F12.84758 94"009Songkhla
G. tenuistipitata20-8-94 31-Muddy sand30F12.70768 98"010Songkhla

F = Female

3.8 Summary of results on Gracilaria species in Vietnam

AbundanceSalinity (ppt)Temp (°C)SubstrateDepth (cm)Rep StageYield (%)Gel strength (g/cm2)Gelling Temp. (°C)Melting Temp. (°C)Method of extraction 
G. verrucosa20-6-92+++15–1623 50Nov–Jul29.5516 -2–4%NaOHDinh vu, Haiphong
G. blodgettii27-5-93+++2324Muddy-sand70Mar–Jul26.5278 85–87"Phulong, Haiphong
G. tenuistipitata21-6-92+++1622–24Rocky50Jan–Jun19.7338 89–92"Lienvi, Quangninh
G. chorda28-5-93++2322Rocky85Jan–Jul21.5290 85–87"Haininh, Quangninh
G. arcuata7-5-93++2223Rocky85Mar–Jul17.6258 92–93"Dovon, Haiphong
G. bursa-pastoris7-5-93++2623Rocky85Jan–Jul15.7128 92–93"Quanlan, Quangninh
G. verrucosa(1)20-6-92++1623Rocky50Nov–Jun29.5516 82–85"Dinh vu, Hai Phong
 (2)20-6-92++1623-  -27.0456 -"Bang la, Haiphong
 (3)----  -24.5319 -"Cathai, Hiaphong
 (4)20-6-92++1523Rocky45Jan–Jul31.0474 82–85"Yin hung, Quang Ninh
 (5)20-6-92-1523-Rocky50-28.0396 -"Thai thuy, Thai binh
 (6)20-6-92---Rocky -26.9387 -"Hai hau, Nam Ha.
G. gigas28-5-93++2523Rock/sand80Jan–July     Campha, Quangninh


4.1 China

Methods used for Agar Extraction

G. tenuistipitata

First Method of Extraction

Second Method of Extraction

25% NaOH treatment, the rest same as 1st method

Third Method of Extraction

4.2 India

Gracilaria species1 
G. edulis(11)
G. crassa(6)
G. corticata var. cylindrica(9)

Method of Extraction

1 Numbers within brackets indicate the number of samples

4.3 Indonesia

Gracilaria species 
G. edulis(3)
G. lemaneiformis(0)
G. spp.(2)
G. salicornia(2)
G. eucheumoides.(0)

Method of Extraction

Adopted from Chandrkrachang, 1992

Water extraction as the first step, then alkali treatment to the agar afterwards.

4.4 Malaysia

Gracilaria species 
G. changii(8)
G. spp.(2)
Hypnea sp.(1)

Method of Extraction

4.5 Myanmar

Gracilaria species
G. verrucosa
G. edulis
G. crassa
G. millardetii
G. textorii

Method of Extraction

4.6 Philippines

Gracilaria species 
G. fastigiata(8)
G. salicornia(2)
G. spp.(3)
G. changii(9)

Method of Extraction

4.7 Thailand

Gracilaria species 
G. salicornia(1)
G. changii(1)
G. fisheri(1)
G. tenuistipitata(1)

Method of Extraction

4.8 Vietnam

Gracilaria species 
G. verrucosa(7)
G. blodgetti(1)
G. tenuistipitata(1)
G. chorda(1)
G. arcuata(1)
G. bursa-pastoris(1)

Method of Extraction

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