Analysis of winter wheat canopy structure for different plant types of growth period

It has different characteristics of the structural parameters for the same plant type at different growth stages and the different plant type at the same growth stages. Understanding the changes of parameters can improve the inversion precision of LAI and water use efficiency. In this paper, varieties investigations had been made by multi-temporal and bidirectional canopy reflected spectrum and structural parameters in Xiaotangshan Town, Beijing City. The growth changes of multi-angle spectrum and parameters were analyzed. The results showed that bidirectional canopy reflected spectrum had significant differences on the red band for the different varieties, and the best identification period was the jointing stage. The LAI of erective varieties was larger than the loose varieties between setting and jointing stage of the selected varieties. It also showed that it was feasible to identify plant type based on LAI which had the phenomenon of double peaks (at the end of April) from the experiment of 2009. Characteristic scale has the ‘seesaw’ effect for the loose varieties 9428 which is one of the bases for the identification of plant structural types.