Change of Chloroplast Ultrastructure in Radish Seedlings under the Influence of the Photosystem II-Herbicide Bentazon
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چکیده
Bentazon, Chloroplast-Ultrastructure, G rana Formation, Photosystem II-Herbicide, Shade-type Chloroplasts The influence of the photosystem II-herbicide bentazon on the ultrastructure of chloroplasts of radish seedlings (Raphanus sativus L.) was investigated with special emphasis on thylakoid development and grana formation. Bentazon application (10-3 m) induces the formation of broader and higher grana stacks (grana width: 0 .5 -0 .6nm ; greatest frequency: 3 8 thylakoids per granum) than in the control plants (grana width: 0.3 |im; greatest frequency: 2 4 thylakoids per granum). Furthermore, the amount of chloroplast lamellae is enhanced, as are the stacking degree of thylakoids and the grana area. The chloroplasts of bentazon-treated plants appear to be shorter and thicker than in the controls and show all signs of a shade-type adaptation of the photosynthetic apparatus.
منابع مشابه
Herbicides which Inhibit Electron Transport or Produce Chlorosis and Their Effect on Chloroplast Development in Radish Seedlings I. Chlorophyll a Fluorescence Transients and Photosystem II Activity
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