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Hyperspectral Analysis of Wheat Leaf Rust (WLR) Disease: A Review

日期: 2019-03-19
瀏覽次數(shù): 256

M.K. Maid1*

, R.R. Deshmukh2

1*Department of CS and IT, Dr. B. A. M. U, Aurangabad, India

2Department of CS and IT, Dr. B. A. M. U, Aurangabad, India

*Corresponding Author: mm915monali@gmail.com?

Available online at: www.ijcseonline.org?


Abstract— Remote Sensing has wide range of applications in many different fields. Remote Sensing has been found to be a valuable tool in evaluation, monitoring, and management of land, water and crop resources. The applications of remote sensing techniques in the field of agriculture are wide and varied ranging from crop identification, detection of disease on different crops & predicting grain yield of crops. Many remote sensing applications are devoted to the agricultural sector. The selected applications are put in the context of the global challenges the agricultural sector is facing: minimizing the environmental impact, while increasing production and productivity. The application of remote sensing in agriculture typically involves measuring reflectance of electromagnetic radiation in the visible (390 to 770 nm), near-infrared (NIR, 770 to 1,300 nm), or middle-infrared (1,300 to 2,500 nm) ranges using spectrometers. This paper reviews the concept of hyperspectral remote sensing, use of remote sensing in terms of agriculture field, study of diseased wheat leaves using hyperspectral remote sensing.


Keywords—Remote Sensing, Wheat Leaf Rust, Vegetation Indices, ASD Fieldspec4 Spectroradiometer.

I. INTRODUCTION

Remote sensing refers to the activities of ?recording/observing/perceiving (sensing) objects or events at ?far away (remote) places. Remote sensing is a sub-field of ?geography. In modern usage, the term generally refers to the?use of aerial sensor technologies to detect and classify?objects on Earth (both on the surface, and in the atmosphere?and oceans) by means of propagated signals (e.g.?electromagnetic radiation) [1]. The electromagnetic?radiation is normally used as an information carrier in remote?sensing. The reflection of that energy by earth surface?materials is then measured to produce an image of the area?sensed. Generally, Remote sensing can be done on two types?of data namely imagery and non imagery. It can be done?using different kinds of remote sensing devices like ASD?fieldspec Spectroradiometer. Remote sensing have wide?range of applications in various fields, among which?Agriculture plays important role in our day to day life as not?only in india but in many countries agriculture is their?primary source of income and all human beings, animals and?many industries are dependent on agriculture field.?agriculture plays key macroeconomic roles in the?

industrialization of developing countries by relieving saving,?aggregate demand, fiscal, and foreign exchange constraints?on the industrial sector [2].

?In agriculture field winter wheat is one of the highest?yielding crops on the farm [3]. Different climatic factors and?disease symptoms affects the plant growth and it directly?results in yield of crop. Rust are among the most important?

fungal diseases of wheat worldwide [4]. There are three types of rust diseases in wheat crop: Strip Rust, Leaf Rust, Stem Rust.

Wheat rusts are caused by three related fungi [5]:?

? Stripe rust is caused by Puccinia striiformis f. sp. tritici.

? Leaf rust is caused by Puccinia triticina.

? Stem rust is caused by Puccinia graminis f. sp. tritici.

This paper reviews the study of wheat leaf rust (WLR) disease using hyperspectral analysis, different vegetation indices and spectral signatures can be used to estimate the features of diseased and healthy crop. In this review paper ASD Fieldspec4 Spectroradiometer is used for data collection of diseased wheat leaves and healthy wheat leaves. Using different vegetation indices (VIs) biophysical and biochemical properties of crop can be estimated.?

II. BASICS OF REMOTE SENSING

Hyperspectral remote sensing is used for over 100 years for?analysis of various objects and their chemical as well as?biological composition. But hyperspectral sensor offers an?alternate and nondestructive technique for analysis of?

physical and chemical properties of material. Remote sensing?of vegetation is mainly performed by obtaining the?electromagnetic wave reflectance information from canopies?using passive sensors. It is well known that the reflectance of?

light spectra from plants changes with plant type, water?content within tissues, and other intrinsic factors [6].

The reflectance from vegetation to the electromagnetic?spectrum (spectral reflectance or emission characteristics of?vegetation) is determined by chemical and morphological?characteristics of the surface of organs or leaves [7].?

Hyperspectral Analysis of Wheat Leaf Rust (WLR) Disease: A Review

The main applications for remote sensing of vegetation are?based on the following light spectra: (i) the ultraviolet region?(UV), which goes from 10 to 380?nm; (ii) the visible spectra,?which are composed of the blue (450–495?nm), green?(495?570?nm), and red (620–750?nm) wavelength regions;?and (iii) the near and mid infrared band (850–1700?nm)[9,10].

III. HYPERSPECTRAL REMOTE SENSING IN?AGRICULTURE

Spectral data at the leaf and canopy scales have been utilized?to improve the plant disease detection techniques from?remotely sensed observations [11,12], where the visible and?infrared regions are more sensitive to disease development?[13]. The measured spectra can be utilized to early detection?of fungus disease. Moreover, the optimized narrow bands?vegetation indices were employed to discriminate various?disease of wheat [14].?

III.I Wheat Leaf Rust (WLR) Disease

The wheat rust is an important crop disease which has three?types, i.e., wheat yellow rust (WYR), wheat leaf rust (WLR),and wheat stem rust [15].?

Hyperspectral Analysis of Wheat Leaf Rust (WLR) Disease: A Review

WYR disease is identified by a single symptom which occurs?as a narrow yellow stripes parallel to nervures on the leaf,?whereas WLR disease is caused by the Puccinia triticina?fungus and illustrates numerous symptoms simultaneously in?various parts of an infected leaf [16]. The WLR symptoms?vary from leaf to leaf but it presents a yellow color earlier,?then its changes to orange and dark brown. Finally, the?disease symptom ends with the dry leaf [17].

Hyperspectral Analysis of Wheat Leaf Rust (WLR) Disease: A Review

The effect of a disease on the pigments and structure of a?plant and the change in their spectral responses enable?spectroradiometry and remote sensing techniques to detect?plant disease effectively [18].

Crop disease can cause significant yield loss and reduction of?grain quality, which have a negative impact to food security?around the world [19].

IV. EXPERIMENTAL SETUP

IV.I Data Collection

Field spec 4 spectrometer (Analytical spectral device, ASD?Co. USA) shown in following figure having parameter?details in Table 1. Spectrum data export in ASCII text, then it?can analyze spectrum data with different software like ASD?View Spec Pro. Unscramble and MATLAB/ Octave [20].

Hyperspectral Analysis of Wheat Leaf Rust (WLR) Disease: A Review


Hyperspectral Analysis of Wheat Leaf Rust (WLR) Disease: A Review

V. VEGETATION INDICES FOR ESTIMATION OF WLRSYMPTOMS

Spectral data at different scales including leaf, canopy and?landscape-level have been widely used to improve precision?[21-24]. In recent years, researchers have studied various?spectral vegetation indices (SVIs) to detect different?

vegetation diseases [24-26]. Efficient use of spectral data in?detection of plant disease depends on the application. The?spectral regions from 400 to 700 and 700 to 1100 are mainly?influenced by leaf composition of pigments, structure, and?

water content [27]. The effect of a disease on the pigments?and structure of a plant and the change in their spectral?responses enable spectroradiometry and remote sensing?techniques to detect plant disease effectively [28]. There are?

indices derived from reflectance values at several?wavelengths that are able to detect and quantify the leaf?content substances such as chlorophyll, anthocyanin, and?water [29,30].

By using different types of vegetation indices estimation of?biochemical and biophysical properties of crops is possible.?Vegetation indices that are used by many researchers have?shown in following table [31].


Table 2. Different Vegetation Indices

Hyperspectral Analysis of Wheat Leaf Rust (WLR) Disease: A Review

Hyperspectral Analysis of Wheat Leaf Rust (WLR) Disease: A Review

Hyperspectral Analysis of Wheat Leaf Rust (WLR) Disease: A Review

VI. CONCLUSION

As Remote Sensing technology growing rapidly in?technological era and hyperspectral Remote sensing has wide?number of applications not only in agriculture field but also in?different industries which are dependent on agricultural area.?With the help of different spectral characteristics like spectral?signatures, vegetation indices, reflectance spectra we can use?it for discrimination of crops. It can be used to study the?severity of disease in crops, estimating the grain yield of?crops, analysis and growth modulation of crop.?


ACKNOWLEDGMENT?

This work is supported by Dept. of Computer Science and?Information Technology under the funds for Infrastructure?under science and Technology (DST-FIST) with sanction no.?SR/FST/ETI- 340/2013 to Dept. of Computer Science and?Information Technology, Dr. Babasaheb Ambedkar?Marathwada University, Aurangabad, Maharashtra, India.?The authors would like to thank Department and University?Authorities for providing the infrastructure and necessary?

support for carrying out the research.?


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高緯度苔原和針葉林、中緯度闊葉林和草原、高山和 高原地區(qū)普遍存在季節(jié)性、晝夜性甚至持續(xù)數(shù)小時的凍融循環(huán)。北半球近55%的陸地面積經歷季節(jié)性凍融,土壤凍融循環(huán)持續(xù)時間從幾天到150天不等。頻繁的凍融循環(huán)改變了土壤微生物群落結構和代謝,加速土壤有機質的分解,并以溫室氣體(如CO2、CH4和N2O)或溶解有機碳(DOC)的形式排放。這些過程已成為生態(tài)學、凍土學和生物地球化學研究的重點。凍融循環(huán)對地表土壤CO2和CH4通量的影響備受關注。一項研究發(fā)現(xiàn),積雪對冬季土壤呼吸的影響是短暫的,厚度變化對CO2通量影響小。了解活動層過程對多年凍土區(qū)土壤CO2和CH4動態(tài)的響應和反饋至關重要。凍融循環(huán)頻率和持續(xù)時間對高寒地區(qū)土壤碳通量具有重要調控作用。不同生態(tài)系統(tǒng)在融化期具有較高的CO2和CH4通量,研究表明,在近地表土壤凍結期間CO2通量達到峰值,隨后顯著下降。春季融化期(20-30天)的甲烷通量...
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