Skip to main content

Advertisement

Log in

How much do standard area diagrams improve accuracy of visual estimates of the percentage area diseased? A systematic review and meta-analysis

  • Original Article
  • Published:
Tropical Plant Pathology Aims and scope Submit manuscript

Abstract

Plant disease severity, when expressed as percentage area diseased, is commonly estimated visually without or with the aid of standard area diagram sets (SADs). It is generally thought that the use of SADs leads to more accurate and thus more precise estimates, but the degree of improvement has not been characterized in a systematic manner. We built on a previous review and screened 153 SAD studies published from 1990 to 2021. A systematic review resulted in a selection of 72 studies that reported three linear regression statistics for individual raters, which are indicative of the two components of bias (intercept = constant bias; slope = systematic bias) and precision (Pearson’s correlation coefficient, r), to perform a meta-analysis of these accuracy components. The meta-analytic model determined an overall gain of 0.07 (r increased from 0.88 to 0.95) in precision from using SADs. Overall, there was a reduction of 2.65 points in the intercept (from 3.41 to 0.76) indicating a reduction in the constant bias. Slope was less influenced and was reduced slightly (from 1.09 to 0.966), indicating a marginal reduction in systematic bias when using SADs. A multiple correspondence analysis suggested an association of less accurate, unaided estimates with diseases that produce numerous lesions and for which maximum severity of 50% is seldom reached. In contrast, estimates of severity for diseases that cause only a few lesions and those diseases where the lesions coalesce and occupy more than 50% of the organ surface had greater accuracy, which was most pronounced for specimen types other than leaves. By quantitatively exploring how characteristics of the pathosystem and how SADs affect precision and constant and systematic biases, we affirm the value of SADs for reducing bias and imprecision of visual assessments. We have also identified situations where SADs have greater or lesser utility as an assessment aid.

This is a preview of subscription content, log in via an institution to check access.

Access this article

Price excludes VAT (USA)
Tax calculation will be finalised during checkout.

Instant access to the full article PDF.

Fig. 1
Fig. 2
Fig. 3
Fig. 4
Fig. 5
Fig. 6
Fig. 7
Fig. 8
Fig. 9

Similar content being viewed by others

Data availability

All data and R scripts generated for the analysis of the data and production of the figures are publicly available at: https://osf.io/t2yjw/.

References

  • Amanat P (1976) Stimuli effecting disease assessment. Agriculturae Conspectus Scientificus 39:27–31

    Google Scholar 

  • Araújo ER, Resende RS, Krezanoski CE, Duarte HSS (2019) A standard area diagram set for severity assessment of botrytis leaf blight of onion. European Journal of Plant Pathology 153:273–277

    Article  Google Scholar 

  • Arias SM, Álvarez GEG, Patiño PAG (2020) Diagrammatic scale for measuring severity of gray mould in thornless Castilla blackberry (Rubus glaucus Benth). Ciência Rural 50:11

    Article  Google Scholar 

  • Belan LL, Belan LL, da Matta RA, Gonçalves Gomes CA, Alves FR, de Jesus C, Junior W, Moraes WB (2020) Standard area diagram with color photographs to estimate the severity of coffee leaf rust in Coffea canephora. Crop Protection 130:105077

    Article  Google Scholar 

  • Bock CH, Parker PE, Cook AZ, Riley T, Gottwald TR (2009) Comparison of assessment of citrus canker foliar symptoms by experienced and inexperienced raters. Plant Disease 93:412–424

    Article  CAS  PubMed  Google Scholar 

  • Bock CH, Pethybridge SJ, Barbedo JGA, Esker PD, Mahlein AK, Del Ponte EM (2021a) A phytopathometry glossary for the twenty-first century: towards consistency and precision in intra- and inter-disciplinary dialogues. Trop Plant Pathol. https://doi.org/10.1007/s40858-021-00454-0

  • Bock CH, Chiang KS, Del Ponte EM (2021b) Plant disease severity estimated visually: a century of research, best practices, and opportunities for improving methods and practices to maximize accuracy. Trop Plant Pathol. https://doi.org/10.1007/s40858-021-00439-z

  • Bock CH, Poole GH, Parker PE, Gottwald TR (2010) Plant disease severity estimated visually, by digital photography and image analysis, and by hyperspectral imaging. Critical Reviews in Plant Sciences 29:59–107

    Article  Google Scholar 

  • Bock CH, El Jarroudi M, Kouadio LA, Mackels C, Chiang K-S, Delfosse P (2015) Disease severity estimates - effects of rater accuracy and assessment methods for comparing treatments. Plant Disease 99:1104–1112

    Article  CAS  PubMed  Google Scholar 

  • Bock C, Chiang KS, Del Ponte EM (2016) Accuracy of plant specimen disease severity estimates: concepts, history, methods, ramifications and challenges for the future. CAB Reviews 11:1–21

    Article  Google Scholar 

  • Bock CH, Barbedo JGA, Del Ponte EM, Bohnenkamp D, Mahlein A-K (2020) From visual estimates to fully automated sensor-based measurements of plant disease severity: status and challenges for improving accuracy. Phytopathology Research 2:9

    Article  Google Scholar 

  • Braido R, Gonçalves-Zuliani AMO, Janeiro V, Carvalho SA, Junior JB, Bock CH, Nunes WMC (2014) Development and validation of standard area diagrams as assessment aids for estimating the severity of citrus canker on unripe oranges. Plant Disease 98:1543–1550

    Article  PubMed  Google Scholar 

  • Braido R, Gonçalves-Zuliani AMO, Nocchi PTR, Junior JB, Janeiro V, Bock CH, Nunes WMC (2015) A standard area diagram set to aid estimation of the severity of Asiatic citrus canker on ripe sweet orange fruit. European Journal of Plant Pathology 141:327–337

    Article  Google Scholar 

  • Brás VV, Rios JA, Silva LC, Eduardo C, Santos M, Nascimento RSM, Rodrigues FÁ (2020) Standard area diagrams to assess scab severity of entire margined leaves of sour passion fruit. Journal of Phytopathology 2020:1–12

    Google Scholar 

  • Camara G de R, Busato LM, Almeida BF, Moraes WB (2018) Elaboration and validation of diagrammatic scale for lettuce powdery mildew. Summa Phytopathologica 44:116–121

    Article  Google Scholar 

  • Castellar C, Jauch F, Moreira RR, da Silva Silveira Duarte H, De Mio LLM (2021) Standard area diagram set for assessment of severity and temporal progress of apple blotch. European Journal of Plant Pathology 160:599–609

    Article  Google Scholar 

  • Chiang K-S, Liu S-C, Bock CH, Gottwald TR (2014) What interval characteristics make a good categorical disease assessment scale? Phytopathology 104:575–585

    Article  PubMed  Google Scholar 

  • Cobb N (1892) Contributions to an economic knowledge of the Australian rusts (Uredineae). Agricultural Gazette of New South Wales 3:44–48

    Google Scholar 

  • de Melo VP, Mendonça ACS, de Souza HS, Gabriel LC, Bock CH, Eaton MJ, Schwan-Estrada KRF, Nunes WMC (2020) Reproducibility of the development and validation process of standard area diagram by two laboratories: an example using the Botrytis cinerea / Gerbera jamesonii pathosystem. Plant Disease 104:2440–2448

    Article  PubMed  Google Scholar 

  • Del Ponte EM, Pethybridge SJ, Bock CH, Michereff SJ, Machado FJ, Spolti P (2017) Standard area diagrams for aiding severity Estimation: scientometrics, pathosystems, and methodological trends in the last 25 Years. Phytopathology 107:1161–1174

    Article  PubMed  Google Scholar 

  • Domiciano GP, Duarte HSS, Moreira EN, Rodrigues FA (2014) Development and validation of a set of standard area diagrams to aid in estimation of spot blotch severity on wheat leaves. Plant Pathology 63:922–928

    Article  Google Scholar 

  • dos Santos PHD, Mussi-Dias V, Freire M Das GM, Carvalho BM, da Silveira SF (2017) Diagrammatic scale of severity for postharvest black rot (Ceratocystis paradoxa) in coconut palm fruits. Summa Phytopathologica 43:269–275

    Article  Google Scholar 

  • Forbes G, Jeger M (1987) Factors affecting the estimation of disease intensity in simulated plant structures. Journal of Plant Diseases and Protection 94:113–12O

    Google Scholar 

  • Franceschi VT, Alves KS, Mazaro SM, Godoy CV, Duarte HSS, Ponte EMD (2020) A new standard area diagram set for assessment of severity of soybean rust improves accuracy of estimates and optimizes resource use. Plant Pathology 69:495–505

    Article  Google Scholar 

  • Hjellbrekke J (2018) Multiple correspondence analysis for the social sciences. Routledge

    Google Scholar 

  • Hock J, Kranz J, Renfro BL (1992) Tests of standard diagrams for field use in assessing the tarspot disease complex of maize (Zea mays). Tropical Pest Management 38:314–318

    Article  Google Scholar 

  • James WC (1974) Assessment of plant diseases and losses. Annual Review of Phytopathology. 12:27–48

    Article  Google Scholar 

  • Kranz J (1977) A study on maximum severity in plant disease. Travaux dédiés à G. Viennot-Bourgin, Sociétée Francaise de Phytopathologie, Paris 1977:169–173

    Google Scholar 

  • Kublik G, Henkemeier NP, Lorenzetti E, Stangarlin JR, Kuhn OJ, Assi L (2020) Desenvolvimento e validação de escala diagramática para avaliação da severidade da bacteriose em mandioca. Revista de Ciências Agroambientais 18:75–81

    Google Scholar 

  • Large EC (1966) Measuring Plant Disease. Annual Review of Phytopathology 4:9–26

    Article  Google Scholar 

  • Lin LIK (1989) A concordance correlation coefficient to evaluate reproducibility. Biometrics. 45:255–268

    Article  CAS  PubMed  Google Scholar 

  • Madden LV, Hughes G, van den Bosch F (2007) The study of plant disease epidemics. APS Press, St. Paul

    Google Scholar 

  • Madden LV, Piepho H-P, Paul PA (2016) Statistical models and methods for network meta-analysis. Phytopathology 106:792–806

    Article  CAS  PubMed  Google Scholar 

  • Montero YM, Rivera LR, Gutiérrez LNG (2021) Diagrammatic scales for the estimation of black node disease severity in common bean. Ciência Rural 51:3

    Article  Google Scholar 

  • Nascimento FA, Duarte HS, Souza FF, Ishikawa FH, Capucho AS (2020) Development and validation of a standard area diagram set to assess powdery mildew severity on watermelon leaves. Ciência Rural 50:10

    Article  Google Scholar 

  • Nita M, Ellis MA, Madden LV (2003) Reliability and accuracy of visual estimation of phomopsis leaf blight of strawberry. Phytopathology 93:995–1005

    Article  CAS  PubMed  Google Scholar 

  • Nutter FW Jr (1993) Assessing the accuracy, intra-rater repeatability, and inter-rater reliability of disease assessment systems. Phytopathology 83:806

    Article  Google Scholar 

  • Nutter JF, Teng P, Shokes FM (1991) Disease assessment terms and concepts. Plant Disease 75:1187–1188

    Google Scholar 

  • Pereira WEL, de Andrade SMP, Del Ponte EM, Esteves MB, Canale MC, Takita MA, Coletta-Filho HD, De Souza AA (2020) Severity assessment in the Nicotiana tabacum-Xylella fastidiosa subsp. pauca pathosystem: design and interlaboratory validation of a standard area diagram set. Tropical Plant Pathology 45:710–722

    Article  Google Scholar 

  • R Core Team (2021) R: A language and environment for statistical computing. R Foundation for statistical computing, Vienna

    Google Scholar 

  • Rivera JF, Duarte HSS, Furtado EB, Dallagnol LJ (2020) A standard area diagram set for severity assessment of eyespot on rice. Australasian Plant Pathology 49:367–371

    Article  Google Scholar 

  • Robaina RR, Longhi TV, Zeffa DM, Gonçalves LSA, Leite RP (2020) Development of a protocol and a diagrammatic scale for quantification of bacterial leaf streak disease on young plants of maize. Plant Disease 104:2921–2927

    Article  PubMed  Google Scholar 

  • Schwanck AA, Del Ponte EM (2014) Accuracy and reliability of severity estimates using linear or logarithmic disease diagram sets in true colour or black and white: a study case for rice brown spot. Journal of Phytopathology 162:670–682

    Article  Google Scholar 

  • Sherwood RT (1983) Illusions in visual assessment of stagonospora leaf spot of orchardgrass. Phytopathology 73:173

    Article  Google Scholar 

  • Sparks AH, Del Ponte EM, Alves KS, Foster ZSL, Grünwald NJ (2021) Reproducibility in plant pathology: where do we stand and a way forward. Preprint. https://doi.org/10.31220/agriRxiv.2021.00082

  • Spolti P, Schneider L, Sanhueza RMV, Batzer JC, Gleason ML, Del Ponte EM (2011) Improving sooty blotch and flyspeck severity estimation on apple fruit with the aid of standard area diagrams. European Journal of Plant Pathology 129:21–29

    Article  Google Scholar 

  • Teng PS (1981) Validation of computer models of plant disease epidemics: a review of philosophy and methodology. Zeitschrift für Pflanzenkrankheiten und Pflanzenschutz 88:1981

    Google Scholar 

  • Trojan DG, Pria MD (2018) Validação de escala diagramática para quantificação da severidade da antracnose da folha do milho. Summa Phytopathologica 44:56–64

    Article  Google Scholar 

  • Viechtbauer W (2010) Conducting meta-analyses in R with the metafor package. Journal of Statistical Software 36:1–48

    Article  Google Scholar 

  • Yadav NVS, de Vos SM, Bock CH, Wood BW (2013) Development and validation of standard area diagrams to aid assessment of pecan scab symptoms on fruit: standard area diagrams for pecan scab. Plant Pathology 62:325–335

    Article  Google Scholar 

Download references

Funding

Clive H. Bock was funded by the USDA-ARS National Programs through CRIS project 6042-21220-014-00. Sarah J. Pethybridge was supported by the United States Department of Agriculture National Institute of Food and Agriculture (USDA-NIFA) Hatch project NYG-625424. Emerson M. Del Ponte was supported by the National Council for Scientific and Technological Development (CNPq) through a Productivity Research Fellowship (PQ) project 310208/2019-0.

Author information

Authors and Affiliations

Authors

Contributions

EMD conceptualized the work, performed the analysis, and wrote the manuscript; CHB conducted experiments and wrote the manuscript; LIC and KAS collected the data, conducted experiments, and revised the manuscript; and SJP conducted experiments and revised the manuscript. All authors have read and agreed to the published version of the manuscript.

Corresponding author

Correspondence to Emerson M. Del Ponte.

Ethics declarations

Conflict of interest

The authors declare no competing interests.

Additional information

Publisher’s note

Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.

Supplementary Information

Below is the link to the electronic supplementary material.

Supplementary file1 (DOCX 32 KB)

Rights and permissions

Reprints and permissions

About this article

Check for updates. Verify currency and authenticity via CrossMark

Cite this article

Del Ponte, E.M., Cazón, L.I., Alves, K.S. et al. How much do standard area diagrams improve accuracy of visual estimates of the percentage area diseased? A systematic review and meta-analysis. Trop. plant pathol. 47, 43–57 (2022). https://doi.org/10.1007/s40858-021-00479-5

Download citation

  • Received:

  • Accepted:

  • Published:

  • Issue Date:

  • DOI: https://doi.org/10.1007/s40858-021-00479-5

Keywords

Navigation