YIELD AND NUTRITIONAL QUALITY OF GREENHOUSE LETTUCE (Lactuca sativa L.) AS AFFECTED BY GENOTYPE AND PRODUCTION METHODS
Society of Geneticists of Serbia
Greenhouse experiments were conducted in winter growing seasons in order to evaluate the effects of genotype and production methods on yield and nutritional quality of lettuce (Lactuca sativa L.). A three-year (2009-2011) study was conducted by randomized block system in a greenhouse without additional heating. The trial included three genotypes of lettuce (Archimedes RZ, Santoro RZ, Kibou RZ). Each row with these genotypes was exposed to the following variants of covering: control-planting on bare soil, mulching before sowing with PE-black foil, agro textile-covering plants after planting with agro textile (17 g), a combination of mulching + agro textile. Throughout of all the three years of the trial, it was continuously evidenced that the genotype “Santoro RZ” had the biggest heads and the highest yield (15.33 kg 10 m-2), which leads to conclusion that the yield of lettuce is a genotype characteristics. Moreover, the nutritional value (ascorbic acid concentration) has shown that, depending on the method of production, in average, the combination of mulching + agro textile (26.77 mg 100 g-1) had the highest content while the control variant had significantly lower vitamin C content (21.10 mg 100 g-1). The three-year researches have shown that the production method and genotype significantly affect the nitrate content. An average nitrate content was 2196.33 mg kg-1 on the control variant, and 2526.24 mg kg-1 on agro textile. Leafy lettuce of genotyp „Kibou RZ“ had lower nitrate content (2176.85 mg kg-1) compared to „Archimedes RZ“ (2843.05 mg kg-1) and „Santoro RZ“ (2221.37 mg kg-1). However, nitrate concentration in all treatments remained within the European Union’s permissible levels.
lettuca,genotype, nitrate content, vitamine C