| 引用本文: | 黄 鑫,佟 玲,康德奎,等.种植密度和水分胁迫对玉米灌浆特性与源库关系的影响[J].灌溉排水学报,2022,41(6):12-20. |
| HUANG Xin,TONG Ling,KANG Dekui,et al.种植密度和水分胁迫对玉米灌浆特性与源库关系的影响[J].灌溉排水学报,2022,41(6):12-20. |
|
| 摘要: |
| 【目的】从籽粒灌浆特性和源库关系的角度探讨不同种植密度和水分胁迫水平下玉米产量形成机制，为西北地区玉米生产实现节水增产提供理论依据。【方法】于甘肃武威绿洲农业高效用水国家野外科学观测研究站进行田间试验，设置2个种植密度水平（7万、9万株/hm2）及3个水分胁迫水平（无水分胁迫、轻度水分胁迫和中度水分胁迫），分析不同种植密度和水分胁迫水平对玉米籽粒灌浆特性、生物量积累、产量和产量构成因素以及源库关系的影响。【结果】①增加种植密度导致上、中、下各粒位百粒质量减小，而施加水分胁迫导致中、下粒位百粒质量减小，处理间籽粒质量差异主要来源于下部籽粒，增加种植密度和施加水分胁迫导致上、中、下各粒位活跃灌浆期缩短，增加种植密度降低各粒位平均灌浆速率，而施加水分胁迫降低中、下粒位平均灌浆速率。②施加水分胁迫导致单株和单位面积生物量减小，增加种植密度导致单株生物量减少，单位面积生物量增加，施加水分胁迫导致玉米产量、穗长、穗粗、穗粒数和百粒质量减小，增加种植密度则显著提高单位面积产量，但导致百粒质量、穗粒数和单株产量的减小，单株产量降低是百粒质量与穗粒数共同降低作用的结果。③不同粒位百粒质量影响因素不同，上部籽粒百粒质量由平均灌浆速率和活跃灌浆期共同影响，中部籽粒百粒质量主要由平均灌浆速率影响，而下部籽粒百粒质量主要由活跃灌浆期影响，中部籽粒灌浆特征参数与单株产量和产量构成因素相关性最好，选取中部籽粒进行灌浆特性分析具有可靠性，单株产量受平均灌浆速率显著影响。④各处理下产量均受限于库强度，从源库关系角度可考虑密度的进一步增加，并且高种植密度结合轻度水分胁迫可最大限度将作物生物量积累转变为经济产量，为本研究中最佳组合模式。【结论】增加种植密度和施加水分胁迫导致上、中、下各粒位活跃灌浆期缩短，中、下粒位平均灌浆速率降低，从而影响各粒位籽粒百粒质量；单株产量主要受平均灌浆速率影响，进而影响单位面积产量；各处理下产量均受限于库强度，高种植密度结合轻度水分胁迫为本研究最佳组合模式，且可考虑密度的进一步增加。 |
| 关键词: 玉米；种植密度；水分胁迫；灌浆特性；源库关系 |
| DOI：10.13522/j.cnki.ggps.2021629 |
| 分类号: |
| 基金项目: |
|
| The Combined Effect of Planting Density and Water Stress on Grain Traits of Maize |
|
HUANG Xin, TONG Ling, KANG Dekui, HE Yujiang, WANG Wanzhen, YANG Shengju
|
|
1. Center for Agricultural Water Research in China, China Agricultural University, Beijing 100083, China;
2. National Field Scientific Observation and Research Station on Efficient Water Use of
Oasis Agriculture in Wuwei of Gansu Province, Wuwei 733009, China;
3. Shiyang River Basin Water Resources Utilization Center, Gansu Provincial Water Resources Department, Wuwei 733000, China
|
| Abstract: |
| 【Objective】Planting density and irrigation are two agronomic practices which can be manipulated to improve water use efficiency and crop yield in semi-arid regions. In this paper we studied their combined impact on formation of maize grain as well as mass translocation from leave to seeds in northwest China. 【Method】The field experiments were conducted at the National Field Scientific Observation and Research Station on Efficient Water Use of Oasis Agriculture at Wuwei, Gansu province. There were two planting densities: 70 000 plants/hm2 and 90 000 plants/hm2, and three water stress treatments: sufficient irrigation, mild water stress, and moderate water stress. For each treatment, we measured the grain-filling traits, biomass accumulation, crop yield and yield components, as well as mass translocation. 【Result】①Increasing planting density reduced the 100-grain weight of the seeds, while imposing water stress reduced the 100-grain weight of seeds on the basal and middle parts of the cobs only. The difference in grain weight between treatments was mainly due to the difference of seeds on the basal part of the cobs. Increasing planting density combined with water stress shortened the active grain-filling period of the seeds. Increasing planting density alone reduced the average grain-filling rate of the seeds, while water stress reduced the average grain-filling rate of the seeds on the middle and basal part of the cobs. ②Water stress reduced biomass per plant, as opposed to increase in planting density which reduced the biomass per plant. The yield per plant, ear length and diameter, grains per ear and 100-grain weight all decreased as the water stress increased. Increasing planting density significantly increased yield, but reduced the 100-grain weight, grains per ear and yield per plant, with the reduction in yield per plant mainly caused by the decrease in reduced 100-grain weight and grains per ear. ③Change in 100-grain weight of seeds at different locations on the cobs was affected by different factors, with that on the tip, middle and basal parts of the cobs impacted by average grain-filling rate and active grain-filling period, average grain-filling rate, and active grain-filling period, respectively. The grain-filling parameters of seeds on the middle cob was best correlated with the yield per plant and yield components. The yield per plant was significantly affected by the average grain-filling rate. ④The yield depended on mass translocation from leaves to grain which varied with planting density. Dense planting density combined with mild water stress maximized conversion of vegetive biomass into economic yield. 【Conclusion】Increasing planting density and water stress shortened the active grain-filling period, and reduced the average grain-filling rate of the seeds on the middle and basal part of the cobs. The average grain-filling rate affected the yield per plant and yield per unit area. Dense planting density combined with mild water stress was the optimal agronomic practice. |
| Key words: maize; planting density; water stress; grain-filling traits; source-sink relationship |
