Effect of Climatic Conditions, and Agronomic Practices Used in Organic and Conventional Crop Production on Yield and Nutritional Composition Parameters in Potato, Cabbage, Lettuce and Onion; Results from the Long-Term NFSC-Trials

Background: There is increasing evidence that the reliance on synthetic chemical pesticides and mineral fertilizers in agriculture has significant negative environmental and/or health impacts poses a risk for future food security. Systematic reviews/meta-analyses showed organic production systems, which omit use of agrochemicals, produce crops with lower yields, but superior nutritional composition. However, agronomic parameters responsible differences crop yields quality are poorly understood. Methods: Here we report results four field vegetable from Nafferton Factorial Systems Comparison (NFSC) trial. This long-term factorial experiment was designed to (i) identify effects growing season/climatic variation, contrasting rotational designs, protection protocols fertilization regimes used conventional systems health, yield (ii) estimate relative importance climatic drivers nutritionally relevant parameters. Quality monitored harvested products, included phenolic, glucosinolate, vitamin C, B9, carotenoid, cadmium (Cd), nickel (Ni), lead (Pb) glycoalkaloid concentrations. Results: Climatic conditions during season were found have larger impact than factors (pre-crop, protection, fertilization) studied. interactions between identified by ANOVA associations three (precipitation, temperature, radiation) differed substantially plant species. Among factors, had compared both pre-crop protection. Specifically, be significantly increased methods potato, fertilization, cabbage, (iii) lettuce, while none effect onion yields. When important pest diseases assessed, resulted late blight severity bird damage cabbage root fly (CRF) incidence cabbages, Sclerotinia lettuce CRF respectively. concentrations phytochemicals compared, higher phenolic glucosinolate carotenoid C potato B9 lettuce—but toxic glycoalkaloids potato. Significant phytochemical only detected resulting metal Cd all Ni onion. where Pb not affected any factors. The potential implications improving strategies reduce non-renewable resources productivity other low-input without compromising discussed. Conclusions: study confirms result phenolics desirable phytochemicals, metals products. It also demonstrates, first time, this primarily due regimes. finding (cabbage, onion) application products no measurable positive should considered context concern about pesticide crops.