关键词: 间作, 青贮玉米, 紫花苜蓿, 种植密度, 种植行数, 生产性能

Abstract: Intercropping of grass and beans can bring into play a synergistic effect of competition and complementarity between crops， improve system productivity and increase land use efficiency. In this study， monoculture maize（Zea mays L.） was used as the control. The sowing rows of maize （1，2，3 rows， Denote as： M₁， M₂and M₃） and the sowing density of maize （60 000 plants·hm^-2， 75 000 plants·hm^-2， 90 000 plants·hm^-2， Denote as： D₁， D₂and D₃） were interplanted with alfalfa（Medicago sativaL.）. A total of 9 alfalfa-maize intercropping modes were set. The effects of different planting rows and density of silage maize intercropping with alfalfa on the performance of silage maize were studied. The results showed as follows： （1） Different intercropping row number and density had significant effects on plant height， stem diameter， number of green leaves， number of yellow leaves， leaf area and ear weight of silage maize. In the intercropping mode， the equivalent ratio of each treatment land was greater than 1. （2） The hay yield of M₃D₃ population was the highest， reaching 30.76 t·hm^-2. （3） Row number and density of silage maize had significant effects on crude protein （Crude protein，CP）and relative feeding value（Relative feeding value，RFV）. CP and RFV contents of M₃D₃ were increased by 5.92% and 4.57%， respectively， compared to CK group. According to the comprehensive ranking by the principal component method， the sequence of intercropping silage maize patterns was as follows： M₃D₃>M₃D₁>M₃D₂>M₂D₂>M₂D₃>M₂D₁>M₁D₃>M₁D₂>M₁D₁. In conclusion， when three rows of intercropping maize were planted in Hexi irrigation area and the density was 90 000 plants·hm^-2， the production performance of silage maize was the best.

Key words: Intercropping, Silage corn, Alfalfa, Planting density, Planting rows, Production performance