Abstract:

To explore the impacts of applying nitrogen, phosphorus and potassium fertilizers, as well as micro elements, on the yield and quality of black corn, black corn ‘SK9179’, ‘SK9176’ and ‘SK9115’, which were self-selected breeding, were taken as test materials, and a multi-point comparison and repeated test design was carried out. The effects of formula fertilizers with nitrogen, phosphorus and potassium ratios of 2:1:2 and 2:1:1， and the supplementary application of the micro elements zinc and boron on the yield and quality of black corn were investigated. Both the 2:1:2 and 2:1:1 NPK ratios were found to enhance the yield and quality of black corn, with the ratio 2:1:2 demonstrating the most favorable results. Applying 0.75% zinc sulfate at the ratio of 2:1:2, the yield of ‘SK9179’ black corn reached the highest 18223.5 kg/hm², and the anthocyanin contents in the corn kernels and cobs were as high as 0.40% and 1.68%, respectively. However, the combined application of zinc sulfate and borax was observed to decrease the yield and quality of black corn. An excessive amount of nitrogen in the soil had a negative impact on the accumulation of anthocyanins and the formation of yield in black corn. Therefore, it was recommended that during the cultivation of black corn, the application amount of nitrogen fertilizer should be reduced, while the application amounts of phosphorus and potassium fertilizers should be increased.

Key words: black corn, nitrogen, phosphorus and potassium fertilizers, micro elements, yield, quality