NITRITE-SULFATE INTERACTIONS AND THEIR EFFECTS ON POTASSIUM AND SODIUM CONTENT OF WHEAT SEEDLINGS

Potassium, sodium and sulphur content of winter wheat (Triticum aestiv um L. cv. GK Othalom) seedlings grown hydroponically in the presence o f different concentrations of sodium nitrite and sodium sulphate at pH 6.5 were studied. The toxic effect of nitrite on the sulphur and pota ssium contents appeared in roots and shoots, but in roots it was more expressed. Nitrite decreased the S contents even at the highest (10 mM ) sulphate concentration. The K contents steeply declined with increas ing NaNO2 and Na2SO4 concentrations, while Na contents were not reduce d by both anions, and increased with the increasing external Na+ amoun ts, the elevated Na content of shoots was definitely due to the nitrit e. This Na+ accumulation in upper plant part reflects the injury of Na +-exclusion mechanism of roots.