为探究硅肥不同喷施浓度对玉米抗倒伏性能及产量的调控效应，本试验以“先玉335”为供试品种，在玉米拔节期（30%叶龄指数时期）设置了4个叶面硅肥（以SiO2计）叶面喷施浓度水平，即4 g/L（S1）、8 g/L（S2）、12 g/L（S3）、16 g/L（S4），以喷施清水为对照处理（CK），比较分析了灌浆期不同处理下玉米茎秆形态特征、基部节间力学特性及产量构成因素的差异变化。结果表明：叶面喷施硅肥对玉米株高、穗位高影响不明显，但可显著降低植株重心高度，以S3处理降幅最为显著，达6.02%；玉米基部第3节节间茎粗、茎壁厚度、横截面积、鲜密度、单位节间茎长干物重、抗折力和穿刺强度等指标，随着叶面喷施硅肥浓度的增加均呈现先升后降的变化趋势，而且与CK处理相比均有不同程度的提高；基部节间长度、扁平率则随着喷施硅肥浓度的加大而表现为逐渐下降趋势，喷施适宜浓度硅肥促进了茎秆机械强度的改善，以及玉米倒伏发生风险的降低；叶面喷施适宜浓度的硅肥，对玉米产量和产量构成均有明显的促进作用，其中S2～S4处理玉米籽粒产量显著高于CK处理，以S3处理产量最高，为11485.68kg/hm2。综合玉米茎秆抗倒伏性能及产量表现，本试验条件下8～12 g/L为拔节期调控玉米抗倒伏能力、实现玉米丰产的叶面硅肥最佳喷施浓度。
In order to explore the effect of different silicon fertilizer concentrations for foliar application on the lodging resistance and grain yield of maize, ‘Xianyu 335’ was used as the tested variety, four concentrations (measured by SiO2) of foliar silicon fertilizer at maize jointing stage (30% leaf age index period) were set up, that is, 4 (S1),8 (S2), 12 (S3), 16 (S4) g/L, and control treatment (CK) was sprayed the same volume of water. In this study, the morphological characteristics, inter-node mechanical properties of stalk at filling stage and yield components at maturation period under different treatments were comparative analyzed. The results showed that the effects of foliar application of silicon fertilizer on plant height and ear height was not obvious, but the height for plant's center of gravity were significantly reduced. Compared with CK treatment, height for plant's center of gravity of S3 treatment was reduced by 6.02% which was the most significant one among four concentrations of foliar silicon fertilizer. The diameter, stem wall thickness, cross-sectional area, fresh density, dry matter weight per unit stem length, breaking-resistant force (bending resistance) and puncture strength of third internodes showed a trend of increasing first and then decreasing with the increase of silicon fertilizer spraying concentration, all their values under foliar silicon fertilizer application were higher than that under CK treatment, and the degree of increase varied with spraying concentration. Length and oblateness of third internodes was gradually declined with the increase of spraying concentration of silicon fertilizer. Spraying the appropriate concentration of silicon fertilizer promoted the improvement of the mechanical strength of the stalk and reduced the risk of maize lodging. Furthermore, appropriate concentration of foliar silicon fertilizer also significantly promoted the maize grain yield and yield components, of which S2-S4 treatments had significantly higher grain yield than CK treatment, and S3 treatment had the highest grain yield of 11485.68 kg/ha. Comprehensive analyzed stalk lodging resistance characteristic and grain yield levels of maize, in this experiment, 8-12 g/L was the optimum spraying concentration of foliar silicon fertilizer at maize jointing stage, which is benefit to regulate maize lodging resistance and promot higher yield.