Effects of metobromuron and chlorbromuron on the chlorophyll protein complexes and chloroplast ultrastructure of french bean phaseolus vulgaris cultivar king horn wax and pea pisum sativum cultivar cl ire de quin seedlings
E.A.ifi S.; Keresztes, A.; Lang, F.
Photosynthetica 17(3): 407-411
ISSN/ISBN: 0300-3604 Accession: 005314275
Germinated seeds of P. sativum L. and P. vulgaris L. were grown in the presence of 10-4 M metobromuron and chlorbromuron for 6 days in total darkness. The seedlings were then irradiated by white light of 27 W m-2 for 48 and 72 h. Metobromuron caused a significant reduction in the chlorophyll (chl) a content of photosystem 1 (PS 1) in both plant species. Chlorbromuron caused a similar reduction in the relative amount of chl a of PS 1 only after 72 h of irradiation. The relative amount of the P700 chl-protein complex apoprotein was slightly reduced after the treatment in both plants. Metobromuron caused chlorosis of bean leaves and, in the yellow regions of the leaves, vesicles instead of thylakoids were observed. Chloroplasts in the chlorbromuron-treated pea seedlings had grana with increased diameters. Alterations in chloroplast ultrastructure were considered to be a result of subsequent action of electron transport blockage.