Effects of supplemental irrigation on grain yield and water and nitrogen efficiencies of winter wheat in the North China Plain.

Background: Aiming at unbalanced coordination of irrigation and fertilization of winter wheat in the eastern North China Plain, this study investigated the effect of fertigation on wheat grain yield, grain quality, and water use efficiency (WUE) and nitrogen use efficiency (NUE) in seven irrigation and nitrogen (N) fertilization treatments. Under the field conditions, the traditional irrigation and fertilization method (total N amount of 240 kg ha , application of 90 kg ha at sowing irrigation at jointing and anthesis, with topdressing N of 150 kg ha at jointing) was used as the control (CK). There were six fertigation treatments to compare with CK.

Canopy occupation volume as an indicator of canopy photosynthetic capacity.

Leaf angle and leaf area index together influence canopy light interception and canopy photosynthesis. However, so far, there is no effective method to identify the optimal combination of these two parameters for canopy photosynthesis. In this study, first a robust high-throughput method for accurate segmentation of maize organs based on 3D point clouds data was developed, then the segmented plant organs were used to generate new 3D point clouds for the canopy of altered architectures.