The objective of this study was to clarify the relationship between light interception in canopy and dry matter production and grain yield in different plant types of maize. The response of morphological characteristics, canopy light distribution, grain filling parameters and dry matter accumulation were studied using three different maize hybrids Shaandan 609 (SD609, compact), Qinlong 14 (QL14, semi-compact), and Shaandan 8806 (SD8806, flat) with four plant densities (4.5×10 4, 6.0×10 4, 7.5×10 4, and 9.0×10 4plants hm -2) in the field from 2016 to 2017. The average yields of SD609, QL14, and SD8806 were 12,176, 9624, and 8533 kg hm -2, respectively, within two years, reaching high yields under 9.0×10 4, 7.5×10 4, and 6×10 4 plants hm -2, with the yield increase of 26.9%, 20.4%, and 19.7% compared with those under 4.5×10 4 plants hm -2, respectively. With the increase of plant density, leaf area decreased, but LAI and leaf orientation value increased. The middle leaves of SD609 were more upright and larger than those of QL14 under 9×10 4 plants hm -2. With increasing plant density, Dmax (days to the maximum grain-filling rate), Wmax (kernel weight at the maximum grain filling rate), Gmax (maximum grain-filling rate), Gave (average grain-filling rate) and P (active filling period) decreased, the Dmax for SD609 was 1.4 days and 3.0 days earlier than that of QL14 and SD8806, and the Wmax and P were higher than those of SD636 (0.3 g and 3.3 d) and SD8806 (1.1 g and 5.4 d), respectively. The dry matter accumulation after silking and the contribution of dry matter transportation to grain yield increased and then decreased with the increase of plant density, the accumulation, transportation and contribution to grain of dry matter after anthesis were higher in SD609 than QL14 (5.1%, 36.0%, 33.5%) and SD8806 (26.6%, 46.7%, 59.1%). The light interception in the ear canopy was significantly correlated with yield (r = 0.631, P < 0.05), the dry matter accumulation after silking (r = 0.661) and average grain filling rate (r = 0.859) at P < 0.01. Thus, compared with QL14 and SD8806, SD609 could regulate the mid and upper leaves more vertical under close planting, improve the light distribution in the mid and lower canopy, maintain a higher area of green leaves, delay the senescence of canopy leaves, increase dry matter accumulation after anthesis and grain filling rate, so obtain a higher grain yield.
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