Table 5 Examples of different general spectral vegetation indices and disease-specific vegetation indices used to detect and measure severity of various plant disease

General spectral vegetation indices

Normalized Difference Vegetation Index (NDVI)

Chlorophyll

(R₈₀₀-R₆₇₀)/(R₈₀₀ + R₆₇₀)

Rouse et al. (1974) Tucker et al. (1991)

Plant Senescence Reflectance Index (PSRI)

Pigment content, Senescence

(R₆₈₀-R₅₀₀)/R₇₅₀

Merzlyak et al. (1999)

Carotenoid Reflectance Index (CAR1)

Carotenoids

1/R₅₁₀–1/R₅₅₀

Gitelson et al. (2002)

Anthocyanin Reflectance Index (ARI)

Anthocyanins/Yellow rust (wheat)

1/R₅₁₀–1/R₇₀₀

Gitelson et al. (2001) Zheng et al. (2018)

Photochemical Reflectance Index (PRI)

Photosynthesis, Carotenoids/Yellow rust (wheat)

(R₅₇₀-R₅₃₁)/(R₅₇₀ + ₅₃₁)

Gamon et al. (1992) Zheng et al. (2018)

Normalized Difference Spectral Index (NDSI)

Leaf spot diseases (peanut)

(R₈₀₀ − R₆₇₀)/(R₈₀₀ + R₆₇₀)

Rouse et al. (1974) Chen et al. (2019)

Disease-specific vegetation indices

Cercospora Leaf Spot Index (CLSI)

Cercospora leaf spot (sugar beet)

(R₆₉₈-R₅₇₀/(R₆₉₈ + R₅₇₀)-R₇₃₄

Mahlein et al. (2013)

Sugar Beet Rust Index (SBRI)

Sugar beet rust (sugar beet)

(R₅₇₀ − R₅₁₃)/(R₅₇₀ + R₅₁₃) + (1/2*R₇₀₄)

Mahlein et al. (2013)

Powdery Mildew Index (PMI)

Powdery mildew (sugar beet)

(R₅₂₀ − R₅₈₄)/(R₅₂₀ + R₅₈₄) + R₇₂₄

Mahlein et al. (2013)

Leaf Rust Disease Severity Index 1 (LRDSI_1)

Brown rust (wheat)

6.9*(R₆₀₅/R₄₅₅)-1.2

Ashourloo et al. (2014)

Leaf Rust Disease Severity Index 2 (LRDSI_2)

Brown rust (wheat)

4.2*(R₆₉₅/R₄₅₅)-3.8

Ashourloo et al. (2014)

Red Edge Disease Stress Index (REDSI)

Yellow rust (wheat)

(705–665)*(R₇₈₃ − R₆₆₅) − (783–665)*(R₇₀₅ − R₆₆₅)2 × R₆₆₅

Zheng et al. (2018)

Lemon Myrtle-Myrtle Rust Index (LMMRI)

Myrtle rust (myrtle)

(R₅₄₅/R₅₅₅)^5/3*R₁₅₀₅/R₂₁₉₅

Heim et al. (2019)