Yield and quality of tomato (Lycopersicon esculentum Mill.) fruit harvested from plants grown in mulched soil

A study investigating the yield of field-grown tomatoes was conducted in 2007–2009 in the Garden of the Research and Experimental Station of the University of Warmia and Mazury in Olsztyn. The experimental materials comprised two tomato cultivars, 'Bawole Serce' and 'Z oty O arowski'. Tomato plants were grown in bare soil and in soil mulched with black non-woven PP 50 fabric. Cultivar selection had a significant effect only on average early yield of 'Bawole Serce'. The highest average early yield for three years of the study was recorded for 'Bawole Serce' grown in mulched soil, while the lowest one for 'Z oty O arowski' grown in mulched plots. Tomato marketable yield was significantly higher in both treatments where 'Bawole Serce' plants were grown. Fruits harvested from tomato plants 'Z oty O arowski' had a higher dry matter content. Soil mulching significantly increased the dry matter content of 'Z oty O arowski' tomato fruit. The experimental factors had no influence on the concentrations of L-ascorbic acid, total sugars, and organic acids. Nitrate levels in tomato fruit were within permissible limits, and they were significantly affected by the cultivation method and the method x cultivar interaction. Nitrate accumulation was reduced in tomato plants 'Z oty O arowski' grown in mulched soil.