54. The country studies and the presentation of the regional overviews and resource papers were followed by discussions, which are summarised below.
A. Country papers
55. The Bangladesh study, which was restricted to shallow waters around St. Martin's Island, did not reveal the presence of any species of Gracilaria. The Bangladesh participant requested the introduction of Gracilaria species from Myanmar or India. In discussions, caution was recommended because of concerns over the possible negative effects on biodiversity which might arise.
56. Bangladesh wanted studies to be initiated on Hypnea spp. and Sargassum spp. Prof. Alfsen, resource person from CNRS, Paris, advised that the countries should utilise the seaweed resources that are available locally. Dr. Suwalee, regional resource person in processing, indicated that Hypnea spp. is a source of carrageenan used in the food, cosmetics and pharmaceutical industries. Research on this topic was not being carried out in Bangladesh owing to a lack of trained personnel, equipment and material supplies. Remedying this situation required international co-operation and support.
57. The China study presentation was made by a researcher from Shanghai Fisheries University, who replaced the original study participant. It was pointed out that studies on seaweed taxonomy, processing technology and production are well established in Chinese institutions and that there is a need to share expertise with other member countries of NACA. This point was re-iterated in the resource paper presented by Prof. Chen Jiaxin, resource person from Yellow Sea Fisheries Research Institute, China.
58. In India, Gracilaria edulis was the most common species. Agar production is based on wild stocks. The culture of seaweeds is still largely experimental. There is considerable information in India on the taxonomy of Gracilaria, but the present study was restricted to the southern part of India (around Mandapam). Commercial culture of Gracilaria and other seaweeds is yet to be established and the support of suitable extension programmes will be needed.
59. In the Indonesian study, Prof. Khanjanapaj, regional resource person on taxonomy, pointed out that the scientific names applied to G. eucheumoides and G. salicornia are correct, but the other species (G. edulis and G. lemaneiformis) need verification. There was a need to collect specimens with reproductive structures for examination. Dr. Destombe, resource person from University of Lille, France, advised of the need for collecting information on growth rates and its relationship with agar content and quality. The need for estimates based on larger samples was also suggested. Indonesian Gracilaria showed desirable characteristics of high gel strength, and low gelling temperatures of agar extracted. The comparative methods of extraction are described in Annex III.
60. It was suggested that taxonomic descriptions in the Malaysian study were incomplete, that there should be complete descriptions of each species and that the G. changii identification had to be verified. There is a need for assistance in taxonomic identification by the referral centre (Kasetsart University, Faculty of Fisheries), through NACA, and more training in taxonomy and processing in Gracilaria. It was pointed out by Prof. Alfsen that countries with capabilities, such as Malaysia, should have some of these training programmes organised within their national centres, with possibly some external assistance through organisations such as NACA. Dr. Destombe also pointed out the need for collecting samples all through the year to obtain a better picture of seasonal effects on agar yield and quality of Gracilaria.
61. The Myanmar study gave complete taxonomic descriptions. The regional resource person in taxonomy pointed out that the name G. crassa should be changed to G. salicornia, and that the specimen identified as G. verrucosa could be G. lemaneiformis. There was no male plant in the collection to verify the reproductive structure and so it could not be confirmed. The resource person in processing technology indicated that Myanmar should have more development in processing techniques and product development. The agar quality observed was not good and needed improvement. The regional resource person from the Philippines, Prof. Trono, wanted to know details of the post-harvest methods adopted. He noted that high moisture content in dried Gracilaria can result in poor quality of agar. Former Chief Technical Adviser, FAO-UNDP Seaweed Project in Philippines, and resource person from Myanmar, Dr. Nyan Taw, indicated that the post-harvest methods could be below standard and that there was need for improvement.
62. For the Philippines' study, the regional resource person for taxonomy advised that the species identified as G. fastigiata should be changed to G. edulis. G. heteroclada, G. tenuistipitata and G. firma give good quality of agar and high yields (16–20%) and are recommended for fanning. A separate study on Gracilaria from the Philippines was reported in a resource paper from SEAFDEC Aquaculture Department. This was a study over the period 1988-1994 and gave a good description of the production ecology, agar yield and quality and culture of selected Gracilaria species, including socio-economics aspects of culture. Polyculture of Gracilaria with finfish (Lates calcarifer) and also with Penaeus monodon was explained. An interesting aspect was that variations in agar quality measured over the year showed a seasonal difference of 10-fold, suggesting the need for seasonal studies for all candidates for culture and agar production. Prof. Chen Jiaxin commended the study of the economics of culture and pointed out that more attention must be paid to studies of economics in the countries.
63. Prof. Alfsen observed that the SEAFDEC study is a model study for all countries and the training facilities and technology available should be made use of by the other countries. Socio- economic benefits of the operations of culture should be made available to the countries and the producers, the small farmers and fishermen. On the issue of species names used, it was pointed out that different taxonomic schools adopt different methodologies, but the workshop agreed on the need for standardisation.
64. In the Thailand study, of the seven species reported G. fisheri and G. tenuistipitata, occurring in the southern coastal area, were considered best for culture. To a question from the Malaysian participant, the resource person in taxonomy stated that there are 13 species of Gracilaria in Thailand. Prof. Trono indicted that there are several ecotypes in G. firma. Prof. Alfsen suggested that agar yield and quality of Gracilaria species should be studied over different seasons and correlated with growth rates. The resource person for processing pointed out that G. fisheri from southern Thailand is known to yield good quality agar (700–900 g/cm2, gel strength) during December to June.
65. The Vietnam study had the benefit of a visit and advice by the regional resource person in taxonomy. The samples studied came from wild stocks. G. verrucosa (G. asiatica) was known to give high yields of agar and high gel strength but agar quality could be improved. Vietnam made a proposal that a Centre of Gracilaria Studies be established at Hai Phong, Vietnam. The Research Institute of Marine Products, Hai Phong, has several different activities in Gracilaria culture and processing, including a Gracilaria physiology laboratory.
66. Sri Lankan and Iranian government nominees participated as special invitees, but were not study participants. The paper from Sri Lanka reported very early studies on Gracilaria (1977–78), and more recent studies in 1994. Sri Lanka would like to conduct further studies as well as culture trials of Gracilaria. As Sri Lanka's Gracilaria areas are contiguous to India's the studies made in India would be relevant (to an extent) to Sri Lanka. Iran plans to develop their aquatic seaweed resources, including Gracilaria, and would welcome assistance in formulating the development plan, as well as organising research and training of personnel.
B. Presentations by resource persons
67 The following summarises the discussions which followed the presentations from the resource persons.
68 The major problems in Gracilaria taxonomy were discussed by the resource person in taxonomy. She indicated that lack of reproductive structures in samples sent by the participants to the Referral Centre made the identification of the species difficult. Also the number of specimens, especially of male plants, was often limited. She noted that the variation in Gracilaria was also high. The resource person advised the following action on country reports from the participants: Some species names should be changed according to the synonymies established. The names of uncertain species should remain the same as shown in the reports, with a notation, “uncertain species”. These would need re-examining to determine the correct nomenclature. Some countries - Indonesia, Myanmar and Vietnam - need more training in taxonomy. As a general need, it would be advisable to select trainees based on their basic background and subject experience.
69. Dr. Barbaroux's resource paper explained the global aspects of the culture of Gracilaria. While agar is used basically for food in Asia, in developed countries it is used for bacteriological and other high-tech purposes. He advised that the socio-economics and trade of agar should be closely watched, especially in expanding culture and production of Gracilaria, to avoid market saturation and low profit.
70. Prof. Trono's review clearly indicated the future directions for development in Gracilaria culture, which included: selection and development of fast growing seed stocks with high quality agar; polyculture; appropriate culture methods and sites; environmental aspects of polyculture; and improvement of post-harvest methods. The NACA Adviser asked if seaweed culture has been associated with fish stock enhancement in any country. Prof. Trono indicated that fish do congregate in these culture sites, especially in floating rafts, possibly because of the cleaner environment. Dr. Phillips wanted to know if there was any quantified information in this. Prof. Trono observed that there have been no studies carried out.
71. Dr. Destombe explained the use of Rubisco spacer analysis in the speciation study of Gracilaria. The Malaysian participant wanted to know how much agreement there was between the morphological and molecular study. Dr. Destombe explained that the range of speciation can be known. Dr. Destombe remarked that the level of studies were very different among the participating countries and in some reports details of analytical and statistical methods were missing. Further improvement in the regional study can be effected through: co-operation between the NACA member countries; an annual or bi-annual NACA publication providing information on new techniques, listing new publications on genetics, taxonomy, biology and physiology of Gracilaria; and the creation of a Centre of Reference, and a library with books, journals and other publications.
72. Prof. Suwalee, resource person in processing, reviewed the processing aspects of the studies, also indicated in the comments in Annex III. Prof. Suwalee wanted each country to set up its own laboratory to continue research and development of agar processing, possibly with funding assistance through co-operative efforts for training personnel, equipment supply and other needs, emphasising the regional co-operation among the member countries. She also wanted progress to be monitored to evaluate the activities and problems.
73. Prof. Alfsen, explaining her involvement in research in algal chemistry, observed that a difficulty she has faced in trying to help through training in developing countries is in locating those who need it. She emphasised that countries should work towards self-reliance. As a general observation on the country studies on Gracilaria, Prof. Alfsen observed that each country should choose for itself the species recognised as giving the best agar yield and gel strength, using whatever species name identified. Standard methods should be used for describing the species, location and season of growth, season for harvest to obtain best yield, growth stages, etc. Standard methods for agar extraction and analysis should be used. The geographical range of each species within the country should be known. Long-term plans for algae production, according to the needs of the country (nutrition, pharmacological, therapeutic), the involvement of manpower and needs for training, should be made for each country.
74. Phytosanitation through utilisation of Gracilaria was explained in the paper by Mr. Kanit Chaiyakham, resource person from the National Institute for Coastal Aquaculture (NICA) in Thailand. The environmental aspects of algal culture was of great interest, also with respect to earlier references to this in Prof. Trono's directions for development. Dr. Nyan Taw wanted to know the objective of the utilisation of Gracilaria. In Malaysia, cockle and Gracilaria were cultured in effluent water to reduce coastal water pollution, he said. In the study described in Thailand, treated water is recirculated for re-use in the shrimp pond. Prof. Trono stated that there could be problems with bio-accumulation of heavy metals and chemicals/pesticides in Gracilaria, grown in the shrimp pond, which should be looked into.
75. Mr. Suchart Wongwai, resource person from industry, explained the marketing and trade in Gracilaria and agar. Dr. Barbaroux observed that Mr. Suchart indicated world demand for agar (10,000 tonnes) was attained by 1993 and that the growth rate of the agar industry between 1990–93, was 40%. Prof. Trono and Dr. Destombe cautioned the increasing production and need for agar in the world, leading to possible over production.
76. Dr. Nyan Taw explained the activities of the FAO/UNDP Project on Gracilaria culture in the Philippines, specifically the socio-economic aspects. Dr. Hurtado-Ponce observed that the socio- economic study done in SEAFDEC was more elaborate, to which Dr. Nyan Taw replied that the elaborate socio-economic study in his project was done by Mr. Tagarino, whose work is cited in his (Taw's) paper.
