烟株叶片叶绿素的时空分布特征

  目的  探讨烟株叶片叶绿素的时空分布特征。  方法  2018年5-9月，利用平均相对偏差、回归分析和相关性分析等方法研究烟株叶片叶绿素的时空分布特征。  结果  1）烟株叶片叶绿素的动态变化呈“倒勺子”型，且叶绿素含量随部位的上升而增大；叶片发育前中期，叶绿素值呈弱变异，后期则呈中等变异。2）样带上中部和上部叶片叶绿素值的破碎化程度高于下部叶，烟株不同部位叶片叶绿素值的波动具有相似性。3）基于时间稳定性指数最小值得出代表性样点，建立了代表性样点叶绿素值与对应部位叶绿素平均值之间的回归模型。  结论  可利用代表性样点烟株叶片叶绿素值表征对应部位叶绿素的平均值，从而为本区烟田的水肥管理和成熟采收提供理论支撑。 

Spatial-temporal distribution of chlorophyll in leaves of tobacco plants

Objective]The purpose of this paper is to investigate the temporal and spatial distribution characteristics of chlorophyll in tobacco leaves.Methods]From May to September 2018,we designed a field experiment to investigate dynamics of chlorophyll in a small catchment of the Mowei Mountain,Pengshui County of Chongqing,by means of mean relative deviation,regression analysis and correlation analysis.Results]1)The dynamic change of chlorophyll in tobacco leaves exhibited an"inverted spoon"pattern,and the chlorophyll content increased as leaf position rise.In the early and middle stages of leaf development,chlorophyll value showed a weak variation,while in the late stages,it showed a moderate variation.2)The fragmentation degree of chlorophyll value in upper and middle leaves was higher than that in lower leaves on the monitoring sample belt.In one tobacco plant,leaves in different positions had a similar variation of chlorophyll values.3)Based on the minimum value of the time stability index,a representative sample was obtained,and a regression model between the representative sample chlorophyll value and the corresponding position chlorophyll average was established.Conclusion]The chlorophyll values of representative tobacco plants can be used to characterize the average value of chlorophyll in the corresponding positions,which provides theoretical support for water and fertilizer management and mature harvesting in tobacco fields.