Analysis And Research Of Millet Phenotype Features Based On 3D Model

Millet is one of the ancient cultivated crops in China,which has the advantages of high nutritional value,drought resistance and poor fertility.Crop phenotype is the result of the interaction between gene and environment.According its phenotype,we can learn the effect of gene and environment on the yield,quality and stress resistance of crops to a certain extent.At present,there are few researches on the phenotypic determination of three-dimensional spatial information of grains and millet under the condition of dry farming.The information stored in the traditional two-dimensional image can not fully represent the spatial characteristics of crops,such as shape,angle,position,etc.Through the three-dimensional model of crops,important parameters of crops can be obtained,such as crop growth state,biomass estimation value,height,shape,nutrient supply and health conditions.Therefore,this paper proposes a method to measure and analyze the phenotypic characteristics of millet based on three-dimensional model.Firstly,in this study,the sparse reconstruction based on motion recovery structure and the multi perspective solid geometry based on patch are combined.Nine samples are selected from each growth period of three different varieties of millet,and a total of 81 samples are reconstructed in three periods to obtain the corresponding three-dimensional model;Then,conditional filtering and statistical filtering are combined to eliminate the noise points caused by human factors and other factors during the photographing process;Finally,through the denoised millet point cloud model to measure the plant height and leaf area,and analyse the measured value and the actual value of the manual measurement.The differences of plant height and leaf area of three millet varieties are compared and analyzed,so are the results of three-dimensional measurement and two-dimensional measurement.The main results and conclusions are as follows:(1)The influence of interval angle on the accuracy of point cloudIn the 3D reconstruction of millet,by comparing the effects of different camera interval angles on the reconstruction time and the reconstruction accuracy,it shows that when the camera interval angle is 5 °,the reconstruction accuracy and time of millet is the best.(2)Phenotypic measurement and difference analysis of milletThrough regression analysis between the measured values of plant height and leaf area of millet and the real values,it shows that the determination coefficient R~2 is higher than 0.94,which shows that it is feasible to use this method to measure the phenotype of millet in different periods and varieties.Through the analysis of the plant height and leaf area of different varieties of millet,it is found that the difference between Dabaigu,Jingu 21 and Yuanping Millet is caused by the variety difference;the difference between Dabaigu and Jingu21,as well as Dabaigu and Yuanping Millet,is caused by the variety difference,but the difference between Yuanping Millet and Jingu 21 is caused by other factors.(3)Comparison results of 2D measurement and 3D measurementBy comparing the two-dimensional and three-dimensional measurement results of agronomic characters of three different varieties of millet with the real measurement results,it is found that the three-dimensional measurement results are less disturbed by other factors,and the correlation is higher.