Organic vs. conventional field trials: the effect on cauliflower quality

Summary

Cauliflowers represented nearly 10% of the total vegetable production in EU and are rich sources of phytonutrients which positively affect human health. The aim of this work was to evaluate the effect over 6 years of organic (OR) and conventional (CO) field trials on 16 different genotipes of cauliflower, employing crop rotation. Yield of production and quality-nutraceuticals characteristic (dry matter, soluble solid residue, pH, titratable acidity, vitamin C, total polyphenols index, thiols content, antioxidant potential and main volatiles) were determined. Yield and florets weights gave a significant decrease in OR (about 25% on total average) respect to CO. The differences in DM, Soluble Solids, pH and total acidity between each OR and CO genotipes were negligible, don’t showing a quality loss in OR-grown cauliflowers. The vit C content was higher (16% on total average) in OR respect to CO. The total polyphenol index and the thiols content resulted slightly higher in OR, hence the difference resulted not significant with CO fields. The antioxidant profile showed high indexes in OR-grown cauliflowers, but the differences with CO resulted not significant. As regards the volatile amounts, the total average difference between OR and CO resulted not significant, with a difference for the single samplings: 4 resulted higher in CO and 2 resulted higher in OR-grown plants. The most important objective of OR management is to prevent quality loss by the produce respect to the CO one, and it seems that the present experiments meet this objective, with the exception of productivity.