Items

Equations

Classifications

References

SAR

Excellent, Good, Permissible, Doubtful

Richards (1954)

Na (%)

Excellent, Good, Permissible, Doubtful, Unsuitable

Wilcox (1954)

RSC

Good, Medium, Bad

Richards (1954)

PI

Excellent, Good, Unsuitable

Doneen (1964)

SSP

Excellent, Good, Fair, poor

Joshi (2009)

MH

Suitable, Unsuitable

Paliwal (1972)

Kelly’s Ratio

Permissible, Non-Permissible

Kelly (1963)

PS

Excellent to Good, Good to Injurious, Injurious to Unsatisfactory

Doneen (1954, 1962)