Abstract

The aim of the work is to study the effects of different treatments: control, single application of organic manure, two seasons straw returning, a quarter of straw returning combined with nitrogen fertilizer, two seasons straw returning combined with nitrogen fertilizer on the quality index and yield of summer maize; protein, starch, fat content and the amino acid were analyzed using cluster analysis. The results showed that there are significant effects of different fertilization on the quality and yield of maize; the content of maize grain protein content of different straw returning treatments significantly increased by 0.90, 77.03 and 60.6% respectively which was higher than other test treatments. In addition, single organic fertilizer has the most prominent effect on total amino acids. However, the amounts of starch decreased and the less decreased treatment was a quarter of straw returning combined with nitrogen fertilizer treatment for 3.5%. The highest crude fat of grain of the single application of organic manure (M) significantly improved by 24.79%. The results show that different long-term straw and fertilizer affect summer maize in their quality characters; application of organic fertilizer can significantly improve the quality of summer maize, as well as its protein and amino acid content.

Key words: Long-term location experiment, straw returning, quality and yield, summer maize.