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Spectrophotometric and Colorimetric Study of Diseased and Rust

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Spectrophotometric and Colorimetric Study of Diseased and Rust NATIONAL BUREAU OF STANDARDS REPORT U5sa SPECIROPHOTOMETRIC AND CWLCEXMEIRIC STUD! OF DISEASED AND RUST RESISTING CEREAL CROPS By Harry J« Keegan John C* Schleter Wiley A. Hall, Jr., and QLadys M* Haas To U* S. Department of die Air Force Aerial Recocmaissance laboratory Wright Air De'velopment Center Wright-Patterscn Air Force Base, Ohio U. S. DEPARTMENT OF COMMERCE NATIONAL BUREAU OF STANDARDS . V. S. DEPARTMENT OF COMMERCE Sinclair Weeks, Secretary NATIONAL HLREAU OF STANDARDS A. V. Aslin, Director THE NATIONAL BUREAU OF STANDARDS The scope of activities of the National Bureau of Standards at its headquarters in Washington, D. C., and its major field laboratories in Boulder, Colorado, is suggested in the following listing of the di\ isions and sections engaged in technical work. In general, each section carries out specialized research, development, and engineering in the field indicated by its title. A brief description of the activities, and of the resultant reports and publications, appears on the inside back cover of this re[)ort. WASHINGTON, D. C. Electricity and Electronics. Resistance and Reactance. Electron Tubes. Electrical Instru- ments. Magnetic Measurements. Process Technology. Engineering Electronics. Electronic Instrumentation. Elect roeheniis try. Optics and Metrology. Photometry and Colorimetry. Optical Instruments. Photographic Teehnolog\. Length. Engineering Metrology. H eat and Power. Temp<‘ratur<‘ Measurements. ThermodMiamies. Cryogenic Phvsies. Engines and Lubrication. Engine Fuels. Atomic and Radiation Physics. Speetroseop\ . Kadiometrv . Mass Spectrometry. Solid State Phvsies. Eh^etron Ph\si(‘s. Atomic Phvsies. Nuclear Phvsies. Radioaetivitv. X-rays. B(*tatron. Nuch'onic Instruimmlation. Radiological f.quipment. AEC Radiation Instruments. (dicniistrv. Organic (boatings. Surface ClKunistrv . Organic Clnmiistrv . Analv tieal Chemistrv Inorganic Clnmiisirv . fd(‘Ctro<h“position. Gas Chemistrv. Phvsieal Chemistry. Thermo- < h<*mistrv. Sp(‘ctroch(‘inistr\ . Pun* Substanc<*s. Mechanics. Sound. Mechanical lnstniin<*nts. Fluid Mechanics. Engineering Mechanics. Mass and Scab*, (^apacitv, Densitv, and Eluid Meters. Combustion Controls. Organic and Fibrous Materials. Kid)b<*r. Textiles. Pa])cr. Leather. Testing and Specifica- tions. Polv mcr Structur(*. Organic Plastics. I)(*ntal R<*search. Mctall iirgy. Th<*rmal Mctalhirgv. (dicmical M(*tallurgv. Mechanical Metallurgv. Corrosion. Mineral Products. (]<*ramic I'ngincf'ring. Porcelain and Potterv. Glass. Refractories. I'’naniclc»l Metals. (Concreting \lat(*rials. Constitution and Microstructure. Building Technology. Structural fCnginet*ring. Fire Protection. Heating and Air Condi- tioning. Floor. Roof, and Wall (Coverings. (]odes and Sj)(*cifications. Ap]d ic<l Mathc'inatics. Num(*rical \nalvsis. (Comj)utation. Statistical iMigineering. Mathe- matical Phvsies. Data Pro<*cssing Systems. (Comj)onents and ^(‘chniijues. Digital Circuitrv. Digital S)stems. \nalogin* Svst<*ms. Applications lMigim*ering. • Office o( Basic instrnm(*ntation • Office o I W eights and Measures KOI LDER. COLORADO (Cryogenic FCngim*cring. (Jrvog(*nic l‘Cquipnn*nt. Crv ogenic Processes. Properties ol Materials. (C^as Li(piclaction. Radio Propagation Physics. I pj)(*r Atmosphere Research. Ionospheric Research. Regular Propagation Services. Ra<Iio Propagation I^Cngineering. Frc<piencv I tilization Research. Tropospheric Propagation R(*search. Radio Slamlards. High Fr(*(picncv Standards Branch: High f r(*qucncv I'.lectrical Standards. Radio Br<mdcast Service*. High Fr<*<pi<*ncv I mp(*danc<* Stamlards. Microwave Stamlards Bram*h: l^\tr(*m^“ High Fr(*(}iu*n(*v ami Noise*. M ie*re)v\ ave F're*epieMU‘v anel Spe*e*tre)se*e>pv . Mie*re)wave (Cire*uil Stamlards. NATIONAL BUREAU OF STANDARDS REPORT NBS PROJECT MBS REPORT 0201-20-2325 1956 U591 SPECTROPHOTOMEmC AND COLORIMETRIC STUDY OF DISEASED AND RUST RESISTING CEREAL CROPS By Harry J. Keegan, John C* Schleter, Wiley A. Hall, Jr., and Gladys M. Haas Photometry and Colorimetry Section Optics and Metrology Division To U. S. Department of the Air Force Aerial Reconnaissance Laboratory Wright Air Development Center Wright-Patterson Air Force Base, Ohio Air Force Contract No. AF 33(6l6) 52-21 Task Number 62IOU <NBS> U. S. DEPARTMENT OF COMMERCE NATIONAL BUREAU OF STANDARDS Approved for public release by the The publication, reprint! t, is prohibited director of the National Institute of unless permission Is obtai ds, Washington Standards and Technology (NIST) 25,D.C. Such permissii as been specif!- tally prepared if that a| on October 9, 2015 For its own use, PREFACE This is one of a series lof NBS reports of spectrophotometri and colorimetric work done under NBS Project No. 0201-20-2325 entitled Color Reconnaissance Studies, financed by the Aerial Reconnaissance Laboratory, Wright Air Development Center, Wright Patterson Air Force Base, Ohio; Air Force Contract No. 33(6l6) 52-21. The present report on cereal crop diseases was made in cooperation with the National Research Council, Committee on Plant and Crop Ecology, Division of Biology and Agriculture, Dr. Everett F. Davis, Executive Secretary; and with its Sub- committee on Crop Geography and Vegetation Analysis, under the chairmanship of Dr. Robert N. Colwell, Associate Professor of Forestry and Associate Silviculturist in the Experiment Station, Department of Forestry, liiiversity of California, Berkeley, California. Harry J. Keegan Project Leader / SPECTROPHOTQMETRIC AND COLORIMETRIC STUD! OF DISEASED AND RUST RESISTING CEREAL CROPS Harry J. Keegan, John C. Schleter, Wiley A. Hall, Jr., and Gladys M. Haas ^ Abstract This stady involves the development of a method for the detection and for the evaluation of wheat rust and of other cereal crop diseases in the field by means of ground or aerial photography based on spec tropho tometrie and colorimetric analyses of specimens of healthy and diseased cereal crops* To develop this method, measurements of the visible and the near infra- red spectral directional reflectance, or spectral transmittance, of 30 specimens of diseased and non-diseased cereal crop plants and of 6 specimens of rust were made on a General Electric recording spectrophotometer for the spectral range I4.OO to IO8O irdllimicrons . Three of the saitples of rust were measured for spectral transmittance and three for spectral directional re- flectance* All of the 30 specimens of diseased and rust resisting cereal crop plants were measured for spectral directional reflectance; II4 specimens, of which nine were youag wheat plants, two mature heads of wheat, and three young rye plants were grown in pots under controlled conditions at the Plant Industry Station, USDA, Belts ville, Maryland; the remaining I6 were the leaves, heads, and stalks of three species of wheat growi in Ihe field at Stillwater, Oklahoma, and flown to Washington, D. C. for measurement at the National B\areau of Standards* These spec trophotome trie measurements have been illustrated and tables of data are included as well as graphs and tables of chromaticity coordinates dominant wavelength, excitation purity, daylight reflectance, Munsell reno- tations, and ISCC-NBS (Inter -Society Color Council - National Bureau of Standards) color designations. In addition, color difference determinations in terms of the NBS unit of color difference have been made between the same parts of different plants and between diseased and non-diseased parts of the same plants • » Miss Haas is at present employed at the Mare Island Naval Shipyard, San ETrancisco, California. r;T^- OjOO L 'mrz ciiam 'H (IV\ " ^Xl>^. .• .D’ ;!>V. V ^:vbr;iO' 'avJCj' ' '”'0 "v,'.;. bci6 fwx<" -.''i'' ' hciiiK^-i ii0Qf;r>.f' fov "ib e'-v.'. .^.-v *^> ‘ ^ •,^.r‘’r‘ ‘'x'-. yij r : i:? T: ' - . ‘ .• : rtr.' J tD b»a-'X-’X^ do . •" .-...-} • ..•/.••> bi;^ ;, ;.r- iO aoi ^ . ::a . • X 1^'--'^ .r?-t bfzz e£cHj:.tr add lo «»t;f »;i4jTx0a(affi ..badd-'»Ti didd ' • '..••»’sb '' V ;,' o.rcd^iittar'^T' c^.rr. *zo * jj^r-c>iit i :_ !«/' • :? -e oe.-: ^ • :r .*v Bi: /ffi'tsqa ' io br'vV ut.VAi'.v •' L' bxy? bacicifrjc- fb 'to <: '. ? D..id lol •"€' ^^^’'4^o^:i£ oin. !:: -- '5o - ••{•a; f-r:ir'i ' •:^-'- ‘' i : i . '-j'Xov "i . .'-v*''^ . rX.i4M --Ji-O c*ia ^^. .. 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'».o a-rieX ni lo bx r :<y^alr> u. ^ njrjr.,.!!q df>y*i»iibb >. e^Taq ‘ -3.tr .Vr njcj^ ' • ^ ^ t -/ft"' 1C ,4-" , :^iikLv . i ,b >=Tt:MS ' Tel aiiiJ' 4 'xLrf -AX.Txo'iiiBd , '•* - 2 - C on tents Page I. Introduction 3 II. Material k III. Preparation of Specimens k IV. Spectrophotometric Jfeasurements 5 V. Spectrophotometric Results 5 VI. Colorimetric Computations 6 VII. Munsell Renotations and ISCC-NBS Color Designations • ^ • 6 VIII. Color-Difference Confutations 7 IX. Specimens Grown Under Controlled Conditions at Beltsville, Md. 7 Figures ltol7 8 toUl Tables I to IV .142 to Appendix A.. I46 Appendix B ............ 60 X. Field-Grown Specimens from Stillwater, Oklahoma •••••.•• 68 Figures l8to31 69 to 96 Tables V to VIII ••97to 100 Appendix C. ....... 101 Appendix D. 113 XI. Discussion 120 XII. Conclusions 121; XIII. Bibliography 12U Appendix E..
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