Premium
Ca 2+ ‐ and Mg 2+ ‐stimulated ATPases from Roots of Plantago major and Plantago maritima : Response to Alterations of the Level of Mineral Nutrition and Ecological Significance
Author(s) -
KUIPER DAAN,
KUIPER PIETER J. C.
Publication year - 1979
Publication title -
physiologia plantarum
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.351
H-Index - 146
eISSN - 1399-3054
pISSN - 0031-9317
DOI - 10.1111/j.1399-3054.1979.tb01653.x
Subject(s) - plantago , plantaginaceae , salt (chemistry) , botany , biology , halophile , nutrient , atpase , dry weight , chemistry , food science , biochemistry , ecology , enzyme , bacteria , genetics
Growth of Plantago major L., ssp. major L. and ssp. pleiosperma Pilger and P. maritime L. was followed at two levels of mineral nutrition (low‐salt and high‐salt). In addition the response of transfer of plants from low‐salt conditions to high‐salt conditions and vice versa was studied. Growth of the studied Plantago species was strongly stimulated by high‐salt conditions. The Ca 2+ ‐ and Mg 2+ ‐stimulated ATPase activity of microsomal preparations of the roots was also studied. In P. major ssp. major and P. maritime a major pH optimum was observed at pH 6.5, and in addition a second pH optimum was found at pH 8.0. High‐salt plants of these two species were characterized by biphasic stimulation curves for Ca 2+ and Mg 2+ , whereas P. major ssp. pleiosperma showed a monophasic pattern. The ATPase activity per g dry weight of P. major and P. maritima was highest in high‐salt plants. The species investigated here are adapted to relatively nutrient‐rich conditions, and the properties of ATPases (K m , K max , protein content) and the growth responses are discussed in relation to this ecological property.