Možnost použití sušených organických a organominerálních hnojiv jako náhrady za chlévský hnůj u raného květáku

Abstract

Experiments were conducted in field plots to evaluate the effects of three alternative dried organic, or organomineral, fertilizers on yield and quality of the early maturing cauliflower variety, ‘Gameta’. Plots were established in Žabčice (South Moravia, Czech Republic) in 2005–2007. We used the following fertilization treatments: Agormin T, Agro, Dvorecký agroferm, cattle farmyard manure and solo mineral fertilizers, compared to an unfertilized control. All plots, except the control, were fertilized to achieve the same level of nutrients, as determined by the soil analyses and the chosen target yield. We assessed the following traits at harvest: weight of above-ground mass, marketable yield, head weight and head diameter. Levels of ascorbic acid, nitrates, dry matter and mineral ions (potassium, sodium, calcium and magnesium) were measured in the heads. Agormin T significantly increased the weight of above-ground mass and total marketable yield. All organic fertilizers significantly increased head weight and head diameter in comparison to both the unfertilized control and mineral fertilizers. Ascorbic acid levels were not significantly affected by the fertilizers. The highest value of ascorbic acid was observed for farmyard manure, the lowest for Dvorecký agroferm. Dried fertilizers had no positive effect on ascorbic acid levels and total solids, as compared to farmyard manure. In contrast, Agormin T resulted in significantly lower levels of dry matter. Solo mineral fertilization resulted in the highest levels of nitrates in cauliflower heads. Fertilization with Agro and farmyard manure significantly increased the levels of nitrates in heads, as compared to the control, but all values were under the hygienic limit. The different fertilizer treatments did not have any significant effects on the levels of mineral cations. The dried granulated fertilizers Agormin T, Agro and Dvorecký agroferm were shown to be good alternatives to bulky farmyard manure for early ripening cauliflower. Only Agormin T decreased the dry matter content in heads.