采用大田试验, 研究了不同基因型玉米(Zea mays)间作对叶片衰老、籽粒产量和品质的影响。结果表明, ‘豫玉19’(YY19)与‘周单041’(ZD041)、‘郑单958’(ZD958)与‘鲁单981’(LD981)间作, 可提高叶片超氧化物歧化酶(SOD)、过氧化物酶(POD)和过氧化氢酶(CAT)的活性, 降低丙二醛(MDA)含量, 延缓叶片衰老。具体表现为, 在吐丝后10 d, 4个玉米品种叶片中的SOD和POD活性均有所提高或显著提高, ZD041和ZD958叶片中的CAT活性提高或显著提高, YY19和LD981变化不显著; 4个玉米品种叶片中的MDA含量降低。在吐丝后40 d, SOD和POD活性及MDA含量的变化与吐丝后10 d基本一致, CAT活性均有所提高, 其中以YY19较为显著。研究还表明, 间作增加了复合群体产量, 土地当量比(Land equivalent ratio, LER)均大于1, 籽粒品质也有所改善。

Aims Although maize (Zea mays) intercropped with other species enhances utilization efficiency of natural resources such as light, heat, water and fertilizer, which increases yields, it has caused great difficulty in cultivation. Presently, there is substantial agronomic evidence for yield advantage among mixtures, maize intercropping with different genotypes included. Our objective was to investigate the effects of maize intercropping with different genotypes on the senescence of leaves, yield and quality.

Methods We conducted a field experiment on the farm of Henan Agricultural University, Zhengzhou, China, using four maize varieties, three semi-compact plant types (YY19, ZD041 and LD981) and one compact plant type (ZD958). The experimental plots of 6 m×6 m were separated by 1 m. The experiments were planted by hand with rows oriented north-south and spacing of 0.70 and 0.50 m. The ratio of two maize varieties intercropped was 1:1 per row. The planting density was 67 500 plants·hm^-2.There were six treatments: each of the varieties alone, YY19 intercropped with ZD041 (YY19║ZD041), and ZD958 intercropped with LD981 (ZD958║LD981). There were four replicate plots for each treatment, arranged in a randomized complete block design.

Important findingsThe activities of SOD and POD of leaves increased in the intercropping treatments 10 days after silking, which resulted in decreased MDA contents of leaves. The activities of CAT of leaves in ZD041 and ZD958 increased or increased markedly, while YY19 and LD981 decreased slightly. The changes of activities of SOD and POD and contents of MDA in leaves remained similar 40 days after silking. Meanwhile, the activities of CAT of leaves increased, among them YY19 increased significantly. Also, yields, land equivalent ratio (LER) and grain quality were enhanced in the intercopped colonies. Results suggested that suitable maize intercropping with different genotypes would increase the activities of SOD, POD and CAT of leaf, prolong leaf life, increase yield and improve quality.