Table 1.
Algal density in coral nubbins maintained under six environmental treatments and sampled after 48(short term) and 127 hours (long term) after the initiation of the treatments.
Figure 1.
Representative chromatograms illustrating the peaks corresponding to the major pigments peaks denoted are chlorophyll c2 (chl c2) peridinin (per), cis-peridinin (cis-per), diadinoxanthin (Dd), diatoxanthin (Dt) and β-carotene (β-car) in dinoflagellates isolated from corals exposed to low light 25°C, low light 32C, high light 25°C, and high light, 32°C.
Figure 2.
Transmission electron micrographs of a zooxanthella within the endodermal layer of the host coral P. damicornis exposed to 400 µµµµµmoles/meter2/second PAR peak irradiance (low-light) at 25°C and 32°C.
Cp = chloroplast; CpM = chloroplast membrane; HN = host nucleus; MT = mitochondria; Py = pyrenoid body; T = thylakoids; VMe = host vacuolar membrane; Zn = Zooxanthella nucleus. (A) Low-light at 25°C (reference treatment). Magnification 1500×, Scale bar = 5000 nm. (B) Magnified area from boxed area in A. Magnification 8000×, scale bar = 500 nm. (C) Low-light at 25°C, magnified view of thylakoids in the chloroplast. Magnification 8000×, scale bar = 500 nm. (D) Low-light at 32°C. Magnification 2500×, scale bar = 2000 nm. (E) Magnified area from boxed area in D. Magnification 6000×, scale bar = 1000 nm. Arrow indicates intact trilaminate chloroplast membrane. (F) Magnified area from boxed area in D. Magnification 6000×, scale bar = 1000 nm. Arrow indicates diffused and disorganized chloroplast membrane zone.
Figure 3.
Concentration of major photosynthetic pigment ratios of zooxanthellae from the four light treatments collected from all four days of the experiment: (1) low-light at 25°C, (2) low-light at 32°C, (3) high-light at 25°C, and (4) high-light at 32°C.
Entries in each graph give treatment untransformed means (±1 SE). Data were analyzed using two-way analysis of variance with a Holm-Sidak post hoc test. Treatment means with different letters differed significantly as α = 0.05.
Figure 4.
Biochemical parameters assayed from zooxanthellae isolated from corals exposed to the following six treatments and collected on Day 1 of the experiment: (1) dark, 25°C; (2) dark, 32°C; (3) low-light, 25°C; (4) low-light, 32°C; (5) high-light, 25°C; (6) high-light, 32°C.
Entries in each graph give treatment untransformed means (±1 SE) and treatment bar means with different letters differed significantly at α = 0.025 using the Dunnett's Procedure.
Figure 5.
Hydroxynonenal and ubiquitin assayed from isolated zooxanthellae from corals exposed to the following six treatments and collected on Day 1, Day 2, and Day 4 of the experiment: (1) dark, 25°C; (2) dark, 32°C; (3) low-light, 25°C; (4) low-light, 32°C; (5) high-light, 25°C; (6) high-light, 32°C.
Entries in each graph give treatment untransformed means (±1 SE). Data were analyzed using two-way analysis of variance with a Dunnett's Procedure. Treatment means with different letters differed significantly as α = 0.025.
Figure 6.
Transmission electron micrographs of a zooxanthella within the endodermal layer of the host coral P. damicornis exposed to 2007 µµµµµmoles/meter2/second PAR peak irradiance (high-light) at 25°C and 32°C.
Cp = chloroplast; MT = mitochondria; s = starch granule; VMx = Vacuolar matrix; Zn = Zooxanthella nucleus. (A) High-light at 25°C. Magnification 2000×, scale bar = 2000 nm. (B) Magnified area from boxed area in panel A. Magnification 5000×, scale bar = 1000 nm. Arrow indicates coalescence of thylakoid membranes. (C) High-light at 32°C. Magnification 2000×, scale bar = 2000 nm. (D) Magnified area from boxed area in C. Magnification 4000×, scale bar = 1000 nm. Arrow indicates diffused and disorganized chloroplast membrane zone. (E) Magnified area from panel C. Magnification 4000×, scale bar = 1000 nm. X-arrow indicates coalescence of thylakoid membranes. Y-arrow indicates diffusion of thylakoid membranes into the stroma. Z-arrow indicates inverted thylakoid membrane micelle. (F) Magnified area from box in panel E. Magnification 12000×, scale bar = 500 nm. Arrows indicate coalescence of thylakoid membranes.
Figure 7.
Transmission electron micrographs of a zooxanthella within the endodermal layer of the host coral P. damicornis exposed to darkness at 25°C and 32°C.
Cp = chloroplast; Mt = mitochondria; Py = pyrenoid body; Zn = Zooxanthella nucleus. (A) Darkness at 25°C. Magnification 2000×, scale bar = 2000 nm. (B) Magnified area from boxed area in A. Magnification 5000×, scale bar = 1000 nm. (C) Darkness at 32°C. Magnification 2000×, scale bar = 2000 nm. (D) Magnified area from boxed area in C. Magnification 3000×, scale bar = 2000 nm. (E) Magnified area from boxed area in D. Darkness at 32°C. Magnification 8000×, scale bar = 500 nm.