关键词: 玉米花生间作, 玉米穗型, 种植密度, 种间竞争, 间作优势

Abstract:

【Objective】The interspecific competition during the late coexisting period of maize (Zea mays L.) intercropping with peanut (Arachis hypogaea L.) (maize||peanut) is the main problem of inhibition to further the intercropping advantage. The aim of this study was to investigate coordinated effects and mechanism of maize ear type and planting density on interspecific competition in maize||peanut, and to determine the reasonably variety and planting density of intercropped maize, so as to provide a theoretical basis and technical support for achieving high yield of maize||peanut production. 【Method】The experiment was conducted on the farm of Henan University of Science and Technology from 2022 to 2023, utilizing a field randomized block design. The selected maize varieties were ‘Zhengdan 958’ for medium-ear type and ‘MC4520’ for large-ear type, with two planting densities of 5.00×10⁴ plants/hm² (D1) and 4.55×10⁴ plants/hm² (D2) for intercropping. The effects of maize ear type and planting density on interspecific competition and intercropping advantage of maize||peanut were studied. 【Result】The results of the 2-year experiment showed that compared with D1 density medium-ear type ‘Zhengdan 958’ intercropped with peanut (M_D1ZD||P), D2 density medium-ear type ‘Zhengdan 958’ intercropped with peanut (M_D2ZD||P) and D2 density large-ear type ‘MC4520’ intercropped with peanut (M_D2MC||P) could enhance the canopy daily light intensity of peanut during the late coexisting period, and increase the leaf area index and maximum growth rate of peanut. M_D2MC||P increased dry matter accumulation in maize and peanut populations, especially in maize grains and peanut pods by 26.41%-30.11% and 8.06%-8.25%, respectively. M_D2ZD||P and M_D2MC||P could improve the interspecific competitiveness of peanut, and the interspecific competitiveness index A_p, CR_p and K_p were increased by 7.55%-19.10%, 4.23%-9.12% and 9.05%-9.60%, respectively, during M_D2MC||P later coexistence. M_D2ZD||P decreased maize yield by 8.09%-8.19%, decreased the yield of intercropping system and intercropping advantage by 2.23%-2.58% and 7.55%-13.29%, respectively. M_D2MC||P could increase the yield of maize and peanut, and the yield of intercropping system and intercropping advantage were significantly increased by 6.28%-7.45% and 11.85%-27.18%, respectively (P<0.05). 【Conclusion】In this experimental area, compared with the medium-ear type ‘Zhengdan 958’ with a density of 5.00×10⁴ plants/hm² intercropping with peanut, the large-ear type ‘MC4520’ with a density of 4.55×10⁴ plants/hm² intercropping with peanut could exert the individual production potential of maize and ensure that the yield of maize was not reduced. Simultaneously, it was more conducive to the coordination of interspecific light competition during the latter coexisting period of maize||peanut, which improved the interspecific competitiveness of peanut, and increased the yield of peanut. Therefore, this planting pattern was conductive to increase the yield of intercropping system and intercropping advantages.

Key words: maize-peanut intercropping, maize ear type, planting density, interspecific competition, intercropping advantages