Effect of Variety and Production Methods on Nitrate Content in Lettuce

Abstract

Certain trials, the effect of variety and different production methods on the content of damaging substances i.e. nitrate in lettuce leaf were carried out on the experimental field of the Faculty of Agriculture in East Sarajevo during the period of three years. The trial was set in a randomized block-system with three replications and the plot size of 2.4 m2 (0.3x8m). Three lettuce varieties (Archimeds RZ, Santoro RZ, Kibou RZ) were analyzed in the trial. Each row of variety was tested in the following variants of covering: planting on soil that was not covered, mulching with PE-black folium before planting; agro-textile - covering of plants with agro textile (17gr) after planting; combination of mulching + agro textile. The three-year researches have shown that the production method and variety significantly affect the nitrate content. An average nitrate content was 2196.33 mg/kg on the control variant, and 2526.24 mg/kg on agro textile. Leafy lettuce of oak leaf type „Kibou“ had lower nitrate content (2176.85 mg/kg) compared to „Archimed“ (2843.05 mg/kg) and „Santoro“ (2221.37 mg/kg).