种植密度对粳稻群体内部生态因子的影响

[目的]研究移栽不同种植密度对水稻产量和群体内部生态因子的影响,探索水稻合理种植密度、最佳群体内部微环境,为水稻增产提供参考依据。[方法]以‘宁粳3号’和‘南粳9108’为材料,设置6个处理:种植密度为23.85×104穴？hm-2(RS1,行株距为30 cm×14 cm),27.75×104穴？hm-2(RS2,行株距为30 cm×12 cm),28.65×104穴？hm-2(RS3,行株距为25 cm×14 cm),33.3×104穴？hm-2(RS4,行株距为30 cm×10 cm),33.3×104穴？hm-2(RS5,行株距为25 cm×12 cm),40.05×104穴？hm-2(RS6,行株距为25 cm×10 cm)。测定水稻抽穗期和齐穗后20 d群体内部光照强度、温湿度和CO2浓度等生态因子,成熟期测定产量及其构成因素。[结果]随着种植密度增加,干物质积累量和产量呈先增加后减少的趋势,RS4处理的产量最高(‘宁粳3号’为10 671.48 kg？hm-2,‘南粳9108’为10 346.14 kg？hm-2),RS6处理的产量最低(‘宁粳3号’为9 470.61 kg？hm-2,‘南粳9108’为8 866.01 kg？hm-2),差异达显著水平。群体内部的温度、湿度、CO2浓度有较好的规律性,抽穗期和齐穗20 d群体下部、中部、上部的温度和湿度均随着种植密度增加呈上升趋势,CO2浓度则呈下降趋势。群体内部光照强度的表现比较复杂,总体上看RS4处理抽穗期和齐穗20 d群体下部有一个相对较高的光照强度,产量也最高。[结论]产量和群体内部生态因子受到种植密度的影响,而结实率和千粒质量又受到群体内部生态因子的影响,种植密度过高或过低都会导致产量降低。本试验条件下,RS4处理的产量最高,产量构成最协调。
[Objectives]To investigate the effect of planting density on ecological characteristics and yield in rice,exploring resonable planting density,optimal mircroenvironment in the population,to provide a reference for rice production. [Methods]With japonica rice‘Ningjing 3’and‘Nanjing 9108’as test materials. Six treatments,including density for 23.85×104 hill？hm-2(row spacing 1 was 30 cm×14 cm),27.75×104 hill？hm-2(row spacing 2 was 30 cm×12 cm),28.65×104 hill？hm-2(row spacing 3 was 25 cm×14 cm),33.3×104 hill？hm-2(row spacing 4 was 30 cm×10 cm),33.3×104 hill？hm-2(row spacing 5 was 25 cm×12 cm),40.05×104 hill？hm-2(row spacing 6 was 25 cm×10 cm). Detemination of ecological characteristics of light intensity,temperature,humidity,CO2 concentration at heading and heading 20 d time,yield and its components at maturity. [Results]With the increase of planting density,yield and the accumulation of dry weight tended to increase first,and then drop down. The RS4 treatment demonstrated the highest yield(‘Ningjing 3’ and ‘Nanjing 9108’ were 10 671.48 kg？hm-2 and 10 346.14 kg？hm-2,respectively). While the lowest yield was RS6 treatment(‘Ningjing 3’ and ‘Nanjing 9108’ were 9 470.61 kg？hm-2 and 8 866.01 kg？hm-2,respectively),and the difference between them achieved a significant level. A regular change was found in rice population,including the temperature,humidity and CO2 concentration. The temperature and humidity showed an increase trend in the lower,middle and high level in the population after 20 d treatment during the heading and full heading stage,while the CO2 concentration showed a decrease trend. In terms of the illumination intensity,the regulation was complicated in the population. In all,20 d treatment of RS4 during the heading and full heading stage showed relative higher illumination intensity