Influence of Correcting the Acidity of Soil and Usage of Potassium Fertilizers on Physiological, Biochemical Characteristics and Storage Capacity of the Autumn Cabbage

Abstract

Soils are generally fertile in Romania but there are numerous areas with less favourable characteristics, which are, however, planted with cabbage, as consumers’ request and economic needs make it necessary. Variable factors which determined the set-up of the experimental variants were represented by the amendments applied (calcium carbonate) and chemical fertilizers containing potassium. The experimental plots have been organized in three locations with podzolic soils. The research has been focused on the influence of correcting soil acidity and applying potassium fertilization on the qualitative changes and the storage capacity of the autumn white cabbage. Correcting the reaction and the supply of podzolic, acid and low in potassium soils, resulted in a positive change of the cabbage leaves mineral composition, in achieving an optimal ratio between calcium and magnesium - adequate to normal metabolic processes-and in statistically significant reduction of the cells membranes permeability. A significant increase of content in soluble dry substance, soluble carbohydrates and chlorophyll was noticed in the cabbage leaves; titratable acidity increased, but it was not statistically ensured. A significant increase in the production of the marketable cabbage was obtained by applying calcium carbonate corrections on acid soils and by administrating potassium salts; significant positive differences were found on cabbage crops grown on soils with a lower supply in potassium. Significant reduction of the losses caused by evapotranspiration, decay and conditioning, as well as of the total losses were analysed after 140 days of storage.