Global Journal of Science Frontier Research, A: Physics and Space Science, Volume 22 Issue 1

vegetable crops and making a study of their effect from the spectral data of the microscopic components in terms of concentration in chlorophylls. II. M ethodology and M aterials u sed a) Sampling In a field of crops in Yamoussoukro, the sampling took place to the north and in lowland to the south of the Institut National Polytechnique Phélix Houphouët Boigny (INP-HB) by selecting certain weeds likely to cause effects on market garden plants and rice crops. The field trip has been supervised by the Plant Pathology and Biology Laboratory of the INP-HB. During this prospecting, eight (8) samples have been collected, including six samples of selected weeds attacking market garden plants ( Boerhaviadiffusa , Mimosa pigra L. , Perotisindica , Leptochloacarulescens , Imperata cylindrical , and Cassia Mimosoideae ) and two samples of weeds attacking rice crop fields ( Echinochloastagnina and Euphorbia heterophylla ). b) Methodology and strategy for data analysis by multimodal spectroscopy The data acquisition system is described in [7, 8]. The classique light sources have been removed and replaced for all modes by a set of 13 LEDs with wavelengths ranging from 375nm to 940nm. The initial mechanical eyepieces are substituted by a 12-bit CMOS monochrome camera (2592x1944, Guppy - 503B, Vision Allied Technology, with an MT9P031 micron / Aptina sensor), with a pixel size of 2.2 µm x 2.2 µm, which has been used to acquire images.The system automatically obtain a total of 39 spectral images (13 images per mode) for the same scene, using a data acquisition card (NI-DAQ) coupled to a computer, which controls the current intensities for fine adjustments. In addition, the transmission, reflection, and scattering modes are used to acquire microscopic images of each of the weeds collected according to the location targeted for sampling. The thirteen light sources are sufficient to study the optical properties of biological cells . Depending on the study method, the spectra correspond to the microscopic images of the samples obtained from the Yamoussoukro / Ivory Coast. Figure 1: Photo image of the multispectral microscope Through the images acquired of each of the sorted weeds by the multispectral microscope, the most rudimentary technique used to extract of multiple mean spectral signatures as a function of wavelengths in transmission mode, reflection mode, and scattering mode is the technique of multimodal spectroscopy analysis. Microscopic and multimodal measurements have made between ultraviolet and near-infrared. The transmission, reflection, and scattering spectra representative of the weed leaves areextracted after appropriate treatment of the images with the “Matlab” software.The spectra obtained represent the average distributions of the intensities transmitted, reflected, and diffused by the leaf samples of each weed (Figure 3, 4, and 5). The flow chart of the methodology is summarized as follows (Figure 2). © 2022 Global Journals 1 Year 2022 2 Global Journal of Science Frontier Research Volume XXII Issue ersion I VI ( A ) Photosynthetic Study of the Effects of Some Weeds in Rice and Vegetable Fields by Spectroscopic and Multimodal Technique in Yamoussoukro (Ivory Coast) [7]