Abstract:

Effects of five different row spacing on stem mechanic property and photosynthetic physiological indexes of maize were studied under the same density (75000 plants/hm²), and ‘Dafeng 30’ was used as the experimental material. The results showed that the chlorophyll content of three-ear-leaves was the highest at the grain-filling stage when the rate of row spacing was 40 cm×80 cm; the net photosynthesis of three-ear-leaves was the highest at the grain-filling stage when the rate of row spacing was 30 cm×90 cm; the leaf area index (LAI) was the highest from flare opening when the rate of row spacing was 40 cm×80 cm. The single trunk dry matter accumulation was the highest at the rate of row spacing 40 cm×80 cm. It was found that the stalk hard rind penetration strength and stem bending capacity were enhanced with the descend of internodes, in an order from high to low as: 40 cm×80 cm> 50 cm×70 cm> 30 cm×90 cm> 60 cm×60 cm> 20 cm×100 cm. Panicle length, ear diameter, number of grains per panicle and 1000-grain weight had different changes among the treatments, the yield was the highest at the row spacing of 40 cm×80 cm, increased by 7.96% compared with that of the equal row spacing 60 cm×60 cm. Taken together, the best rate of row spacing is 40 cm×80 cm, which is more conducive to photosynthetic characteristics and stem strength of ‘Dafeng 30’, and could achieve the goal of lodging resistance and yield increase.

Key words: maize, density, rate of row spacing, photosynthetic physiological indexes, stem, yield