Premium
SENESCENCE IN SUBMERGED AQUATIC ANGIOSPERMS: EFFECTS OF HEAVY METALS
Author(s) -
JANA SASADHAR,
CHOUDHURI MONOJIT A.
Publication year - 1982
Publication title -
new phytologist
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 3.742
H-Index - 244
eISSN - 1469-8137
pISSN - 0028-646X
DOI - 10.1111/j.1469-8137.1982.tb04480.x
Subject(s) - hydrilla , potamogeton , botany , biology , chlorophyll , cadmium , aquatic plant , respiration , respiration rate , macrophyte , chemistry , ecology , organic chemistry
SUMMARY The effects of mercuric chloride, lead acetate, cadmium chloride and cupric sulphate on the senescence of isolated mature leaves of three submerged aquatic angiosperms, Potamogeton pectinatus L., Vallisneria spiralis L. and Hydrilla verticillata (L.f.) Royle, were studied. All four compounds decreased the rate of respiration of all the species except that Cu increased the respiration rate of Potamogeton . All the heavy metals hastened senescence of all three species as measured by decreases in the contents of chlorophyll, RNA, protein and dry wt and increases of free amino acid content, tissue permeability, the ratio of acid to alkaline pyrophosphatase activity and the activities of protease and RNase. All metals decreased the ratio of chlorophyll a to b in Potamogeton and Vallisneria but increased it in Hydrilla . Cu seemed to be the most effective metal in inducing deleterious effects in Potamogeton and Vallisneria . Pretreatment of leaves of these plants with kinetin for 12 h or more, significantly reduced the senescence promoted by the heavy metals. Of the three species studied, Hydrilla was most tolerant to the heavy metals applied.