Effect of applied fertilization on productivity and quality of spinach (Spinacia oleracea)

Ivanka Mitova, Nikolai Dinev

Abstract: The after-effect of organic (compost), mineral (N, P, K) and combined organo-mineral fertilization on the growth, yield and quality of winter variety "Winter big" was tested. The experiment was based on Alluvial-meadow soil (Fluvisol), pre-winter on November as part of a perennial vegetable crop rotation. During the vegetation, two feedings were made, with foliar fertilizers - Lebozol - Potassium and Aminozole. In the variant with after-effect of organic fertilization with Aminozole, in the variant after mineral fertilization with Lebozol - Potassium, and in the variant with mixed fertilization - the first feeding is with Lebozol - Potassium, and the second with Aminozole.
Experimental results showed that the biometric indicators (plant height, number and weight of leaves, mass of leaf stalks and petioles, as well as leaf area) of spinach plants benefit from the fertilization of the previous crop (potatoes) showed the highest values after fertilizing with mineral fertilizer. The differences in the masses of the plants are statistically proven, as the mass of the plants with the effect of the mineral fertilization is leading - 50.03 grams per plant. The highest yield (117.2 kg.ha-1) is realized by the variant with the effect of the mineral fertilization and two foliar feeds with Lebozol-Potassium. While the indicators dry matter and total sugars do not have statistically proven differences between the variants of the experiment, the highest measured chlorophyll and nitrate content is in plants with effects of mineral fertilization - 57.4 mg.kg-1, as the measured contents in the variants of the experiment are much below the sanitary permissible ones, which defines the production as safe for consumption.

Keywords: compost; mineral fetrilizaton; organic fertilizer; quality

Date published: 2021-11-10