紧凑型玉米正红6号群体结构与密肥优化方案的研究

Study on population structure and optimized model of planting density and nitrogen rate for compact maize Zhenghong 6

采用两因素五水平裂区试验设计方法，研究了种植密度和施氮量对紧凑型玉米正红6号的产量及其群体结构的影响，探讨了群体质量指标与产量的关系，并建立了优化栽培技术模型。结果表明：籽粒产量与成熟期LAI和干物重、吐丝至成熟期的NAR、CGR及干物质积累量呈线性正相关，与吐丝期LAI和干物重呈二次凸函数关系；正红6号产量≥7500kg／hm^2的高产栽培技术方案为：61845-73155株／hm^2，施氮量180．1～419．9kg／hm^2，高产群体结构指标为吐丝期LA14．67～5．27，成熟期LAI1．46～1．87，吐丝后LAD138×10^4-149×10^4m^2·d，吐丝后NAR6．88～8．50g·m^-2·d^-1，吐丝后CGR21．92-25．13g·m^-2·d^-1,吐丝期干物重13954．72～15167．22kg／hm^2，成熟期干物重24503．4～24925．59kg／hm^2。

The effects of planting density and nitrogen rate on yield and population structure of compact maize Zhenghong 6 were studied through a field split plot experiment with two factors, and the relationship between yield and population structure were discussed. The optimized model of planting density and nitrogen rate for high yielding were established. The results indicated that grain yield were positively re- lated to the dry matter weight at maturity stage and that accumulated in the period from silking to matunity,LAI at maturity stage, NAR and CGR in the period from silking to maturity. However, the relationship between grain yield and LAI and dry matter weight at maturity stage were quadratic functions. The cultivation techniques for yield more than 7500kg/hm^2 were as follows： the planting densities were 61 845 -73 155 plant/hm^2 ,while the nitrogen rate were 180. 1 -419.9 kg N/hm^2. The optimal population structure index for high yielding were as follows ： LAI at silking stage were 4.67 - 5.27 while that at maturity stage 1.46 - 1.87, the LAD, NAR and CGR in the period from silking to maturity were 138 ×10^4 - 149 × 10^4 m^2·d, 6. 88 - 8. 50g· m^-2·d^-1 and 21.92 - 25.13 g·m^-2 ·d^ - 1 respectively, the dry matter weight at silking stage and maturity stage were 13954.72 -15167.22kg/hm^2 and 24503.4 -24925.59 kg/hm^2, respectively.