PO 7
WADA,K.T.,KOMARU,A. and Y. UCHIMURA
Triploid production in the Japanese pearl oyster, Pinctada fucata
martensii.
1989 9 pp
Aquaculture, 76: 11–19
The eggs of the Japanese pearl oyster, Pinctada fucata martensii, were treated with cold, heat or cytochalasin B (CB) shocks at various time intervals after insemination to induce triploidy. To detect polyploidy, relative DNA content was estimated by microfluorometry with DAPI staining of larval or juvenile cells. Four experiments were conducted using different batches of eggs. All three treatments resulted in much damage to the development, hatchability and metamorphosis of embryos and growth of larvae. The extent of damage depended mostly on the time of initiation of treatment and the duration of treatment. The most effective procedure for inducing triploidy was the treatment of eggs with 0.5 mg/1 CB from 20 to 50 min after insemination which resulted in 100% (20/20) triploid juveniles. A 0.1 mg/1 CB treatment with the same time schedule produced 80% (16/20 triploids at 3 months of age. Cold shock was also effective for inducing triploidy. The rate of 3 month-old triploid juveniles was 52% (16/31) after treatment with low temperature (6.5°C) from 5 to 15 min after insemination. However, high mortality of larvae was observed.
PO 8
ALAGARSWAMI, K., DHARMARAJ, S., CHELLAM, A. and T.S. VELAYUDHAN
Larval and juvenile rearing of Black-lip pearl oyster, Pinctada
margaritifera (Linnaeus).
1989 14 pp
Aquaculture, 76: 43–56
The black-lip pearl oyster, Pinctada margaritifera (Linnaeus), has been cultured in the experimental shellfish hatchery at Tuticorin, India. The flagellates Isochrysis galbana and Pavlova lutheri were used independently as larval food at a concentration of 5 cells/ul up to day 5 and the ration was doubled thereafter until spat setting. The initial larval density wad 1/ml. Straight-hinge veliger stage (75×60 um) was reached in 20 h, umbo stage (140×130 um) on day 12, pediveliger (220×210 um) on day 20 and plantigrade (260×240 um) on day 23, and spat of 350×300 um appeared on day 28. I. galbana promoted faster growth and early spat setting as compared to P. lutheri. The modal component of the larval population showed an average growth of 10.98 um/day. A total of 6.3% of the initial larval population metamorphosed as spat. Juveniles cultured in the laboratory showed a growth rate of 0.09 mm/day. On transplantation to the culture raft in the farm, growth rate increased to 0.4 mm/day. The juveniles suffered heavy mortality after 4 months. It remains to be tested whether P. margaritifera juveniles would have a greater chance of survival in oceanic island conditions, as the natural distribution of the species in India is confined to the Andaman Nicobar Islands.
PO 9
ALAGARSWAMI, K. (Ed.)
Pearl culture.
1987 136 pp
Bull. Cent. Mar. Fish. Res. Inst., 39
The Bulletin gives a comprehensive coverage of pearl oyster resource and ecology of pearl oyster beds; morphology and physiology of pearl oyster; spat collection in the inshore areas including the harbour basins; methods of pearl oyster farming and farm management; techniques of cultured pearl production and quality of cultured pearls; technology of hatchery production of pearl oyster; sea-ranching; transfer of technology and problems and prospects of earl culture in India. It also includes a chapter giving the results obtained by the Department of Fisheries, Govt. of Tamil Nadu under the ICAR ad hoc Scheme on Pearl Culture. Finally, the Bulletin gives an annotated bibliography of the India works on pearl oyster resource and culture.
PO 10
ALAGARSWAMI, K. and S. DHARMARAJ
Manual on pearl culture techniques.
1984 42 pp
Cent. Mar. Fish. Res. Inst., Special publication, 20
The manual is restricted in its scope, providing only the basic techniques and procedures of pearl oyster farming and cultured pearl production. It does not include the hatchery production of pearl oyster.
PO 11
KRISHNA KARTHA, K.N. (Ed.)
Pearl culture training - Long-term and short-term courses.
1977 39 pp
Cent. Mar. Fish. Res. Inst., Special publication, 1
This publication contains the details of two training courses conducted at the Tuticorin Research Centre and Veppalodai Pearl Oyster farm of the Institute. The first Course, meant to be a ‘trainers’ training course', is a long-term course covering a period of six months, organised for training the officers from the different maritime States. The second, a short-term course of 4 weeks duration, is to train operative personnel in more specific fields of pearl culture.
