Light Detection System in Mature Sunflower (Helianthus annuus L.) Chloroplasts: Wavelength Dependent or Total Photon Flux Density Related?

Exposure to low levels of photosynthetically active radiation induces rapid increases in palisade cell chloroplast volume and thylakoid surface area in sunflower (Helianthus annuus L.)

“…Evidence from over 10 years of studying chloroplast membrane dynamics has resulted in numerous observations of vesicles apparently originating from the inner chloroplast membrane appearing to associate with nonappressed membranes, which seems to support this model (Fagerberg unpubl.). The ratios of appressed to nonappressed thylakoids in this study differed from those found in other studies where low-PAR-acclimated chloroplasts tended to have higher ratios of appressed to nonappressed thylakoids compared to sun-acclimated chloroplasts (Boardman 1977;Fagerberg 1983Fagerberg , 1987Fagerberg , 1988bFagerberg , 1990Fagerberg and Bornman 1997;Ghoshroy and Fagerberg 1998 However, these studies were made on chloroplasts from plants that had been grown under different irradiance conditions or that had experienced a change in irradiance over a longer period than those in this study.…”

“…The day temperature was 21-26 ~ Three mature nonexpanding leaves, one from each of three different plants, were cut at the base of the petiole and taken to the laboratory. Leaf strips (7.0 by 1.0 cm) were cut from the leaves, washed for 20 min in deionized H20, and then placed vertically on filter paper in flasks (Ghoshroy and Fagerberg 1998). The base of each leaf strip was immersed in double-distilled water (1 cm) and heId verticaIly against moist filter papers throughout the sample period (Ghoshroy and Fagerberg 1998).…”

“…Leaf strips (7.0 by 1.0 cm) were cut from the leaves, washed for 20 min in deionized H20, and then placed vertically on filter paper in flasks (Ghoshroy and Fagerberg 1998). The base of each leaf strip was immersed in double-distilled water (1 cm) and heId verticaIly against moist filter papers throughout the sample period (Ghoshroy and Fagerberg 1998). The angle of incidence of the light was 90 ~ .…”

“…Plants grown under red light exhibit an increase in thylakoid membrane surface area compared to plants grown under blue light (Lichtenthaler et al 1980, Voskresenskaya 1984, Mfienpfifi and Aro 1986). However, Ghoshroy and Fagerberg (1998) showed that changes in sunflower thylakoid surface area were a response to total photon flux density rather than wavelength-dependent factors. Fagerberg and Bornman (1997) reported that UV-B stress induced a lowirradiance response in Brassica napus.…”

Rapid, reversible alterations in spinach thylakoid appression upon changes in light intensity

“…1978; Lichtenthaler et al . 1981; Fails, Lewis & Barden 1982; Terashima & Inoue 1985; Eschrich, Burchardt & Essiamah 1989; Ghoshroy & Fagerberg 1998; Yang et al . 1998; Maxwell et al .…”