Effects of interspecific competition on crop yield and nitrogen utilisation in maize-soybean intercropping system

Abstract

Intercropping system plays a crucial role in improving crop yield, nitrogen utilisation efficiency (NUE) and economic benefit. The difference in crop yield and interspecific relationship under different bandwidth and row ratio allocation patterns are still unclear. A field experiment was carried out to explore change regularities between crop yield and interspecific relationships under maize soybean intercropping with different bandwidths and row ratios. The results showed that the yield of intercropped crops was lower than that of the sole crop. The nitrogen accumulation (NA), NUE and nitrogen competition ratio was the highest under the intercropping mode with a bandwidth of 2.0 m, which indicated that this mode was more conducive to the N uptake and utilisation in crops. In all intercropping systems, nitrogen equivalent ratio (NER) and land equivalent ratio (LER) were all greater than one, indicating that intercropping systems were conducive to improving land utilisation efficiency and NUE. Under the same bandwidth pattern, expanding the maize soybean row ratio from 2:4 to 3:4 was beneficial to the improvement of LER, NER, NUE, crop group yield. In conclusion, it was preferable in the NA, NUE, crop group yield under the system of bandwidth 2.0 m and row ratio 2:2, which could be a reference for maize soybean intercropping system.

Keywords

• zea mays l.
• glycine max l.
• rowing spacing
• biodiversity
• nutrient use efficiency