Research On 3D Digitization And Visualization Of Maize Morphological Architecture Based On Phytomer

Phytomer refers to the repeated unit of structure and function of higher plants,and as the scale between organs and individuals,it shows certain advantages in the study of plant structure and function.The realization of three-dimensional visualization technology of maize is of great significance to restore the growth state of maize,study the relationship between maize morphology and structure and function,and realize the transformation of agricultural science to digitalization,visualization,precision and intelligence.This study in maize(Zea mays l.)plants as the object,through the implementation of different period,different plant varieties of field experiment,explored the corn festival unit scale 3D digital technology and phenotypic parameters extraction algorithm,build the corn of the section unit 3 d with the relational model,further implement the 3 d distribution model and canopy model and light photosynthetic productivity model to evaluate the combination of different varieties of plant photosynthetic capacity,for the corn super-high-yield group building and ideal plant type laid a theoretical basis for optimization design.The main research results are as follows:On the basis of previous research and years of field experiments and data acquisition experience,the phytomer composition was defined from the three-dimensional perspective,and the three-dimensional phytomer parameters set and mathematical expression were extracted.According to the definition of phytomer composition,the 3D phytomer data acquisition specification was developed to obtain the 3D phytomer of maize for different plant types,varieties and ecological points.Finally,based on the obtained 3D phytomer data,the 3D node unit template library of maize was constructed,which was used for rapid 3D reconstruction and dynamic simulation of individual and population of maize plants.Different maize varieties were used for materials,and some research on data acquisition methods,comparison of 3D laser scanner,multi-view images and 3D digitizer three methods of data acquisition found multi-view image is better for smaller plant reconstruction,3D laser scanner is better for larger plant reconstruction,but the two methods can only acquire part of the phytomer information;3D digitization can obtain the information of 3D phytomer completely,but the efficiency is low.The obtained phytomer information was extracted with 3D parameters,such as phytomer space distribution,leaf vein curve length,blade curvature,and normalized volume.It was found that the three-dimensional phytomer space distribution of different varieties was varying.DMY2 global phytomer distribution concentration;JK968 whole section unit distribution is dispersed;ZD958 panicle upper phytomer distribution is dispersed,the lower panicle unit distribution concentration.The difference of unit space distribution was parameterized by using normal function.Finally,the accuracy of data acquisition is analyzed,and it is found that the accuracy of 3D digital data acquisition is higher than the other two methods.The analysis results provide a basis for the population and dynamic reconstruction based on 3D phytomer.In order to quickly construct the 3D model of maize canopy with variety resolution,this paper proposes a 3D reconstruction of maize population based on the constraint of the normal distribution function of each plant bounding box and the 3D phytomer template library.In this method,the template is retrieved from the 3D phytomer template library,and the individuals are assembled according to the constraint conditions.RMSE of the reconstruction model was 0.1,and the correlation coefficient R2 was 0.99.Combining with the light distribution model and photosynthetic model,the method can evaluate the light distribution and photosynthetic productivity of different species,ecological sites and cultivation methods(east-west,south-north,equal-row spacing,wide and narrow rows).The results show that the east-west direction group light interception is significantly better than the north-south direction,and the east-west direction has more significant influence on JK968 and ZD958,and the east-west direction increases the group light interception by more than 30%compared with the north-south direction.The difference of row spacing had no significant effect on the light distribution and photosynthetic productivity of different cultivars.The photosynthetic efficiency of DMY2 was significantly higher than that of other varieties by about 45%.Based on the 3D phytomer template library and the 3D phytomer coordinated growth model,the simulation of the 3D morphological process of maize varieties was realized.3D dynamic simulation process was driven by expanded leaf age.On maize plant growth status,macro and micro state was classification.The phytomer number and macro state controlled under expanded leaf age,the micro state of internal organs development was controlled under macro state.For developed phytomer,the phytomer was assembled directly;for developing phytomer,the phytomer was assembled after 3D morphological control.The 3D dynamic growth simulation was realized by traversing all leaf ages in the growth period.After dynamic simulation,the extracted parameters were compared with the measured data,and the correlation coefficient R2 was between 0.87 and 0.96.