National Committee on Marine Sciences (NCMS)
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- Comparison of photosynthetic responses of healthy and ‘diseased’ Kappaphycus alvarezii (Doty) Doty using P vs I curveGanzon-Fortes, E. T.; Azanza-Corrales, R.; Aliaza, T. (Walter de Gruyter GmbH, 1993)Healthy and 'diseased' thalli of Kappaphycus alvarezii were collected from two different sites in Bolinao, Pangasinan, northern Philippines. Their photosynthetic responses to varying photon fluence levels we reassessed. The healthy branches had higher photosynthetic rates (expressed in mgO2 gdw"1 h'1) at all light levels and did not show photoinhibition at photon fluence levels of up to 800 μπιοί photons m~2s~!. The 'diseased' branches showed a significant decrease in their photosynthetic performance as manifested by their lower Pmax, increased Ic, and lower alpha, and a photoinhibition above 600 μιηοΐ photons m~2 s"1. Examination of the concentration of pigments — chlorophyll a, r-phycoerythrin and r-phycocyanin, revealed a significant drop in the 'diseased' plants, suggesting the major role played by these pigments in the observed differences in their photosynthetic responses.
- Wound healing in cultured Eucheuma alvareziivar. tambalang DotyAzanza-Corrales, R.; Dawes, C. J. (Walter de Gruyter GmbH, 1989)Wound healing in segments of Eucheuma alvarezii var. tambalang grown in enriched media in the laboratory can be divided into four stages based on histological and cytological changes. During the first stage, approximately 2—4 days after wounding, proteinaceous and phenolic substances concentrate on pit plugs of cells adjacent to the wounded surface. In the second stage, about the sixth day, cellular extensions are produced from the pits of medullary and cortical cells of sub-wound layer. During the third stage, about the 8th day, the cellular extensions divide several times and elongate towards the surface. A new cortical or wound tissue is formed during the fourth stage beginning on the 12th day. The wound tissue is continuous with the old cortex within 3 weeks.
- The farmed Eucheuma species (Gigartinales, Rhodophyta) in Danajon Reef, Philippines: Carrageenan propertiesAzanza-Corrales, R.; Sa-a, P. (Springer, 1990-09)Six cultured ‘strains’ of Eucheuma denticulatum and E. alvarezii, from which stocks can be selected for the development of a Eucheuma ‘seedling bank’, were tested for their carrageenan quality from June to November 1988. Percent yield of all the varieties taken together was apparently higher in June, becoming lower in November (regression, r −0.785, probability, p ⩽ 0.001). Stepwise regression analysis was done to determine the existence of any relationship between any of the following parameters: gel strength, viscosity, sulfate content, month of sampling, and yield, whether taken individually or in combination. Results show variations of the yield with the month of sampling. ANOVA was performed to test whether there are differences in sulfate levels, gel strength, and viscosity between the Eucheuma alvarezii morphotypes. There was no significant difference between the green and the brown types.