. 2023 Sep 15;23:431. doi: 10.1186/s12870-023-04416-3

Table 3.

Drought tolerance indices used for investigation of Iranian wheat germplasm

Index	Abbreviation	Calculation formula	Reference
Tolerance index	TOL	$Y p - Y s$	[15]
Mean productivity	MP	$\frac{Y p + Y s}{2}$	[29]
Geometric mean productivity	GMP	$\sqrt{Y p \times Y_{S}}$	[30]
Stress tolerance index	STI	$\frac{Y p \times Y s}{{\bar{Y}}_{p}^{2}}$	[31]
Abiotic tolerance index	ATI	$[\frac{Y p - Y s}{\bar{Y} s / \bar{Y} p}] \times (\sqrt{Y p \times Y_{S}})$	[38]
Harmonic mean	HM	$\frac{2 \times Y p \times Y s}{Y p + Y_{S}}$	[29]
Stress susceptibility index	SSI	$\frac{1 - (Y p / Y s)}{1 - (\bar{Y} s / \bar{Y} p)}$	[34]
Drought resistance index	DI	$[Y_{s}, (Y_{s} / Y_{p})] / {\bar{Y}}_{s}$	[29]