关键词: 春玉米, 施肥模式, 覆盖方式, 干物质, 产量

Abstract: It is of significant importance for scientific regional evaluation and rational utilization of fertilization modes to study the dry matter accumulation, yield and water use efficiency (WUE) of spring maize in red soil upland at southern China with different fertilization modes and mulching methods. Taking local routine fertilization modes as CK, this paper studied the effects of different fertilization modes and mulching methods on dry matter accumulation, yield and WUE of spring maize in red soil upland of southern China. The different treatments included conventional fertilization + potassium + organic fertilizer with plastic mulching (TOK); conventional fertilization + organic fertilizer with plastic mulching (TO), conventional fertilization + potassium without mulching (TK). The results showed that the chlorophyll content in leaves of spring maize with different treatments was TOK＞TK＞TO＞CK. And the leaf area per plant and leaf area index of spring maize with TOK and TK treatments were significantly higher than that of CK (P<0.05) at the seedling and jointing stages. While the TOK treatment had remarkable higher leaf area per plant and leaf area index than that of the the CK (P<0.05) at heading and maturing stages. The dry root weights of TOK treatment were remarkably higher than that of the other treatments (P<0.05), and the dry weights of stem and leaf of TOK and TK treatments were notably higher than that of the other treatments(P<0.05) during each main growing stages of spring maize. Meanwhile, the water contents of 0~20 cm soil in different treatments were all higher (P<0.05) than that of the CK at each main growth stages of spring maize. The sequence was TOK>TO>TK>CK. The sequence of WUE was TOK＞TK＞TO＞CK, and TOK treatment had the highest WUE, which increased by 38.04% comparing with the CK. There were not significant differences in ear diameter and row number between TK, TO, TOK treatments and the CK. But the ear length, kernel number, number of grains in an ear and 100-grains weight were remarkably higher than that of the CK. The sequence of spring maize yield was TOK＞TK＞TO＞CK. The grain yield of TOK, TK and TO treatments were increased by 34.41%, 11.72% and 8.36%, than that of the CK, respectively. The above results indicated that based on conventional fertilization, adding organic fertilizer and potassium with plastic mulching are banificial for increasing dry matter accumulation, grain yield and improving WUE of spring maize.

Key words: spring maize, fertilization mode, mulching method, dry matter, yield