以早熟品种陕单650和晚熟品种陕单609为材料,设置4个种植密度研究其对玉米茎秆倒伏特性和产量的影响。结果表明,陕单609和陕单650分别在90 180株/hm²和105 000株/hm²密度下子粒产量达到最高值15 110.0 kg/hm²和18 056.7 kg/hm²。与陕单609相比,陕单650在密植条件下茎节短而粗,抗倒伏能力强。随着密度的增加,玉米茎秆穿刺强度逐渐降低,同一节位下茎秆穿刺强度表现为陕单650大于陕单609,不同节位的穿刺强度均表现为第3节>第4节>第5节。相关分析显示,子粒产量与茎秆强度、节间粗、节间干重呈极显著负相关关系;倒伏率与茎秆强度、单位茎长干重、节间粗、节间干重呈极显著负相关关系,与节间长、株高、穗位高、穗位系数呈极显著正相关关系。早熟品种陕单650密植后茎秆节间短而粗,单位茎长干重较大,抗倒伏能力强,有较多的有效穗数和穗粒数,获得较高的产量。

An experiment was conducted to investigate the effects of planting density on stem lodging resistance and grain yield of spring maize at different maturity stages at the four planting densities with early-maturing variety SD650 and mid-late-maturing variety SD609 as experimental materials. The results showed that SD650 and SD609 reached the highest grain yields of 15 110 kg/ha and 18 056.67 kg/ha under the densities of 90 180 and 105 000 plants/ha. Compared with the SD609, SD650 had shorter and thicker stem nodes, shorter plant height and ear height, and stronger stem lodging resistance under dense planting. The node position, the stem puncture strength of the two hybrids decreased gradually with the increase of density. The stem puncture strength at the same node position was SD650＞SD609, and the puncture strength at different nodes was the third node＞the fourth node＞the fifth node. Correlation analysis showed that grain yield was significantly negatively correlated with stem strength, internode diameter and internode dry weight. The lodging rate was significantly negatively correlated with stem strength, dry weight per unit stem length, internode diameter and internode dry weight. It was significantly positively correlated with internode length, plant height, ear height and ear height coefficient. The internodes of the stalk of the early-maturing variety SD650 were short and thick, the dry weight per stalk length was larger, and the lodging resistance ability was stronger. Additionally, it had a higher effective ear number and grain number per ear, the yield was higher under high density.

S513.047

陕西省农业科技创新计划项目(NYKJ-2022-YL-NY-14)