Enhanced Nutritional Quality of Sweet Maize Kernel in Response to Cover Crops and Bio-Fertilizer

Cover crops (CC) are an important low-input strategy in sustainable agricultural systems. The impact of different CC (common vetch, field pea, winter oats, fodder kale, common vetch + winter oats and field pea + winter oats), organic mulch, control treatment-fallow, and biofertilizer (BF) application, on yield and quality of sweet maize kernel was evaluated. CC biomass was higher in mixtures: field pea + winter oats, and common vetch + winter oats, as well as in fodder kale. Kernel yield and its chemical composition varied significantly by CC, BF, year, and their interaction. Organic mulch enhanced the concentration of sugars and glutathione in maize kernel. BF increased kernel yield, the concentration of sugars, vitamin C, Mg, Fe, Zn, and reduced phytate concentration. The highest Mg and Mn concentration in maize kernel was achieved with fodder kale, Zn concentration with common vetch + winter oats + BF, and Fe concentration with winter oats. The same treatments expressed the highest impact on variability in concentration of the phytate, phenolics, and yellow pigment, thus affecting further bio-availability of essential elements. Results indicate that in a semi-arid climate, under rain-fed conditions, CC such as fodder kale and winter oats + common vetch could enhance sweet maize productivity and kernel quality, serving as an important part of a sustainable cropping system, to facilitate food security.