Detection of chlorophyll content of wheat leaves based on laser scattering images

ZHANG Cui-hong; ZHANG Xiao-juan; ZHU Da-zhou; WANG Cheng

doi:10.3969/j.issn.1001-806.2012.04.007

In order to realize nondestructive test of the chlorophyll content,the optical characteristic parameters of wheat leaves were measured with laser backscatter images.Firstly,the laser backscatter images of wheat leaves were obtained with 670nm and 970nm of semiconductor lasers and a video imaging system.Secondly,based on the diffuse theory,diffusive light distribution of the leaf surface was analyzed,and the laser backscatter images of green leaves,yellow leaves and dry leaves were compared at both the above wavelengths.The optical characteristic parameter data(the reduced scattering and absorption coefficient) were obtained,and the function corresponding to the relative contents of chlorophyll was established.The results show the optical characteristic parameters of wheat leaves and are linear with the relative contents of chlorophyll.In the model predicting the relative contents of chlorophyll value based on the scattering coefficients,the correlation coefficient prediction samples is set 0.9095,prediction root mean square error(RMSE) is 5.9.In the model predicting the relative contents of chlorophyll value based on the absorption coefficients,the correlation coefficient prediction samples is set 0.8366,prediction RMSE is 7.5.The results show that it is feasible to detect plant chlorophyll content and diagnose the crop growth conditions with laser backscatter image technology.

Detection of chlorophyll content of wheat leaves based on laser scattering images

Corresponding author: ZHANG Xiao-juan, lzhangxiaojuan@126.com;

1. College of Science, Civil Aviation University of China, Tianjin 300300, China;

2. National Engineering Research Center for Intelligent Agricultural Equipments, Beijing 100097, China

Received Date: 2011-11-08

Accepted Date: 2011-12-21

Available Online: 2012-07-25

Abstract: In order to realize nondestructive test of the chlorophyll content,the optical characteristic parameters of wheat leaves were measured with laser backscatter images.Firstly,the laser backscatter images of wheat leaves were obtained with 670nm and 970nm of semiconductor lasers and a video imaging system.Secondly,based on the diffuse theory,diffusive light distribution of the leaf surface was analyzed,and the laser backscatter images of green leaves,yellow leaves and dry leaves were compared at both the above wavelengths.The optical characteristic parameter data(the reduced scattering and absorption coefficient) were obtained,and the function corresponding to the relative contents of chlorophyll was established.The results show the optical characteristic parameters of wheat leaves and are linear with the relative contents of chlorophyll.In the model predicting the relative contents of chlorophyll value based on the scattering coefficients,the correlation coefficient prediction samples is set 0.9095,prediction root mean square error(RMSE) is 5.9.In the model predicting the relative contents of chlorophyll value based on the absorption coefficients,the correlation coefficient prediction samples is set 0.8366,prediction RMSE is 7.5.The results show that it is feasible to detect plant chlorophyll content and diagnose the crop growth conditions with laser backscatter image technology.

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Reference (15)

[1]	YANG F,FAN Y M,LI J L,et al.Estimating LAI and CCD of rice and wheat using hyperspectral remote sensing data[J].Transactions of the CSAE,2010,26(2):237-243(in Chinese).
[2]	XU Zh L,WANG Zh Y,HUANG L,et al.Investigation of measurement methods for determining the optical properties of agricultural products tissue[J].Laser Journal,2005,26(6):87-89(in Chinese).
[3]	HU Sh F,LIU M H,LIN H W.A Study on detecting pesticide residuals on fruit surface by using laser imaging[J].Acta Agriculturae Universitatis Jiangxiensis,2006,28 (6):872-876(in Chinese).
[4]	ZHANG X Zh.A comparison of methods of measurement of chlorophyll in plants[J].Journal of Shenyang Agricultural College,1985,16(4):81-84(in Chinese).
[5]	WANG K R,LI Sh K,WANG Ch T,et al.The detection system of chlorophyll content based on computer vision[J].Acta Agronomica Sinica,2006,32(1):34-40(in Chinese).
[6]	DAM J S,DALGAARD T,FABRICIUS P E,et al.Multiple polynomial regression method for determination of biomedical optical properties from integrating sphere measurements[J].Applied Optics,2000,39(2):1202-1209.
[7]	ZHANG L Sh,ZHANG X H,WANG Zh Zh.Determination of optical coefficients of biological tissue by means of diffuse image[J].Laser Technology,2011,35(5):675-677(in Chinese).
[8]	ZHANG X J,LIU Y,GAO Z H.Spatial-resolved diffuse reflectance of tissue close to source[J].Chinese Journal of Lasers,2005,32(4):571-575(in Chinese).
[9]	JOHNS M,GILLER C,GERMAN D,et al.Determination of reduced scattering coefficient of biological tissue from a needle-like probe[J].Optics Express,2005,13 (13):4836-4842.
[10]	PENG Y,LU R.Predietion of apple fruit firmness and soluble content using characteristics of multispectral scattering images[J].Journal of Food Engineering,2007,82(2):142-152.
[11]	LU R.Predicting firmness and sugar content of sweet cherries using near-infrared diffuse reflectance spectroscopy[J].Transactions of the ASAE,2001,44(5):1265-1271.
[12]	ZUDE M,HEROLD B,ROGER J M,et al.Non-destructive tests on the prediction of apple fruit properties at the tree and in shell life[J].Jonrnal of Food Engineering,2006,77(2):254-260.
[13]	QIN Zh Sh,JI B P,SHI B L,et al.Improving apple fruit quality predictions by effective correction of Vis-NIR laser diffuse reflecting images[J].Spectroscopy and Spectral Analysis,2008,28(6):1273-1277.
[14]	WANG Zh Y,HUANG L,HOU R F,et al.Light transport in multilayered farm products by using Monte Carlo simulation and experimental investigation[J].Transactions of the Chinese Society of Agricultural Engineering,2007,23(5):1-7.
[15]	WU Y H,ZHAO J W,CHEN Q Sh,et al.Nondestructive measurement of optical properties of fruit by laser imaging[J].Journal of Jiangsu University(Natural Scionce Edition),2007,28 (1):7-11 (in Chinese).

Detection of chlorophyll content of wheat leaves based on laser scattering images

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