摘要
【目的】探究不同种植密度下制种玉米液流的变化规律和影响因子。【方法】于2015年3—9月进行了制种玉米的大田试验,共设置4个种植密度,分别为9.75万、11.25万、12.75万和14.25万株/hm2,观测了不同种植密度下制种玉米的液流。【结果】不同种植密度下液流速率的变化趋势一致,并且随种植密度的增加而减小;通过相关分析与通径分析表明,小时尺度液流速率(Qh)与气象因子相关性排序为:太阳辐射(Rs)>水汽压差(VPD)>大气温度(Ta)>相对湿度(RH)>风速(Ws);日尺度液流速率(Qd)与气象因子相关性排序为:VPD>Ta>Rs>RH>Ws;相比于茎粗(D),Qd与叶面积指数(LAI)的相关性更高,而与株高(H)无明显关系;全生育期内蒸腾量(T)随种植密度的增加而增加,蒸腾比(T/(E+T))为88%~89%;微型蒸渗仪法(E)加液流法(T)测得的耗水量较水量平衡法低估作物耗水量9%。【结论】Rs是Qh的主要驱动因子,VPD是Qd的主要驱动因子;制种玉米夜间茎流不可忽略。
[Objective] Study the affecting factors and variation of sap flow of seed maize in different planting density. [Method] Field experiments were conducted from March to September in 2015, and the experimental treatments consisted of four planting densities （97 500, 112 500, 127 500 and 1425 00 plants/hm2）. The meteoro- logical factors and sap flow of seed maize plants in different densities condition were observed. [Result] The variation trends of sap flow rate with each planting density were similar and the sap flow rates decreased with the increase of planting density. The correlation analysis and path analysis indicated that the meteorological variables affecting hourly sap flow （Qh）and daily sap flow （Qd） in different planting density were ranked as solar radiation （Rs）〉 water vapor pressure diference （VPD）〉air temperature （Ta）〉ralative humidity （RH）〉wind speed （Ws） and VPD〉Ta〉Rs〉RH〉Ws, respectively. The correlation between Qd and leaf area index （LAD was higher than stem diameter （D）, but the Qd was not significantly correlated with the plant height （H）. Transpiration （T） increased with the increase of planting density and the transpiration ratio （T/（E＋7））was 88%-89% over the whole growth stage. The evapotranspiration measured by micro-lysimeter method （E） plus sap flow method （7） underestimate 9% than water balance method. [Conclusion] Rs is the main driving factor of Qh and the VPD is the main driving factor of the daily Qd. The nightime sap flow of seed maize should not be neglected.
出处
《灌溉排水学报》
CSCD
北大核心
2018年第3期1-8,共8页
Journal of Irrigation and Drainage
基金
国家自然科学基金项目(51379208)
农业公益性行业科研专项经费项目(201503125)
