Cover crops effect on status of main antioxidants in sweet maize

Abstract

Cover crops has important role in sustainability, owing to protection from soil erosion and soil enrichment with organic matter. Bio-fertilizers are important for increase of soil and crop quality. The aim of experiment was to examine nutritional quality of sweet maize, sown at experimental plots after different cover crops: T1 - common vetch (Vicia sativa L.), T2 - winter oats, (Avena sativa L.), T3 - fodder kale (Brassica oleracea (L.) convar. acephala), T4 - field pea (Pisum sativum L.) + winter oats, T5 - dead organic mulch, T6 - common vetch + winter oats, T7 - field pea and control - uncovered during the winter, in combination with bio-fertilizer Uniker, during 2013/2014. Content of main antioxidants: phenolics, glutathione, vitamin C, carotenoids and phytic acid were determined in technological maturity. The highest content of carotenoids (2.48 μg g-1) was obtained in T1 + Uniker combination, while the highest values of glutathione and phenolics were in T2 treatment (1927 nmol g-1 and 716 μg g-1, respectively). T3 was characterized with the highest vitamin C content in combinations with and without Uniker (29.92 and 31.09 mg 100g-1) and control had the highest phytic P content (3.69 mg g-1). Correlation consigned that increased kernel yield was followed by carotenoid increase and phenolics decrease in general, while application of Uniker induced increase of Pphy and decrease of vitamin C, parallel with grain yield increase.