ALTERATIONS IN ELECTRON-TRANSPORT CHARACTERISTICS DURING SENESCENCE OF CUCUMIS COTYLEDONARY LEAVES - ANALYSIS OF THE EFFECTS OF INHIBITORS

Citation
Jss. Prakash et al., ALTERATIONS IN ELECTRON-TRANSPORT CHARACTERISTICS DURING SENESCENCE OF CUCUMIS COTYLEDONARY LEAVES - ANALYSIS OF THE EFFECTS OF INHIBITORS, Photosynthetica, 35(3), 1998, pp. 345-352
Citations number
33
Categorie Soggetti
Plant Sciences
Journal title
ISSN journal
03003604
Volume
35
Issue
3
Year of publication
1998
Pages
345 - 352
Database
ISI
SICI code
0300-3604(1998)35:3<345:AIECDS>2.0.ZU;2-O
Abstract
Cotyledonary leaves of Cucumis sativus cv. Poinsette exhibited senesce nce-induced losses in chlorophyll (Chl) and protein contents within th ree weeks since germination. Chi and protein concentrations in cotyled onary leaves approached maximum on 6(th) d after germination and they declined to 50 and 41 %, respectively, by the 20(th) day of growth. Ac tivities of both photosystem (PS) 2 and PS1 decreased by 33 and 31%, r espectively, on the 20th day, compared to the control 6th day. Changes in sensitivity of PS2 to inhibitors like atrazine and dibromothymoqui none and sensitivity of PS1 to KCN accompanied the changes in PS2 and PS1 activities. Hence both the acceptor side of PS2 and the donor side of PS1 are affected by senescence-induced changes in cucumber cotyled onary leaves.