Seed vigor, aging, and osmopriming affect anion and sugar leakage during imbibition of maize (Zea mays L.) caryopses

Conductivity was significantly increased by aging and decreased by osmoprim ing of maize (Zea mays L.) caryopses. Chloride, phosphate, and sulfate were the main anions that leaked out of maize seeds; their leakage was closely related to conductivity, increased by aging, and decreased by osmopriming. The anion leakage of isolated embryos correlated closely to seed vigor and was more sensitive to aging and priming than that of the whole seed. Anion leakage may be a more sensitive measure for seed vigor than bulk conductivi ty readings. Aging did not increase the sugar leakage of whole seeds but si gnificantly increased the sugar leakage of isolated embryos. Sugar leakage was not closely related to total soluble sugar content of seeds. While prim ing decreased seed conductivity, the decreased anion and sugar leakage of t he primed seeds was mainly caused by the washing effect during priming. The total anions or sugars left in the polyethylene glycol (PEG) solution afte r priming and in the conductivity solution of the primed seeds was almost t he same as in the conductivity solution of the unprimed seeds alone.