Reorganization of the chloroplast thylakoid system during decay of acquired thermotolerance of photosynthesis and aging of wheat leaves
Kisliuk, I.M.; Bubolo, L.S.
Tsitologiia 42(11): 1026-1032
2000
ISSN/ISBN: 0041-3771 PMID: 11204645 Document Number: 519484
A 3 hours heating at 39 degrees C of 14-day old wheat plants increases the termotolerance of photosynthesis, and also the length and number of thylakoids in chloroplast in mature leaves. The acquired termotolerance disappears within 10 days. Simultaneously the intensity of photosynthesis and the length of thylakoids decrease. Reduction of photosynthesis ability and of thylakoid membranes occurs in the first leaves of non-hardened plants during 14-29 days after sowing. The intensity of photosynthesis in plants of both variants positively correlates with the length of grana membranes and with the total length of membranes of all thylakoids. Besides, a positive correlation was detected between the intensity of photosynthesis and the share of small (2-7 thylakoids) grana and the length of their membranes in non-hardened plants. The level of thermotolerance of photosynthesis in leaves in heat hardened plants correlates positively with the length of grana membranes and with the total length of all thylakoid membranes and the share of small grana.