Table 2 Comprehensive evaluation of spinach growth under different concentrations of MeJA.

Plant height

0.0000

0.4674

1.0000

0.3967

Root length

0.0000

0.3415

1.0000

0.5305

Stem thickness

0.0000

0.3909

1.0000

0.5238

Aboveground fresh weight

0.0000

0.4107

1.0000

0.4120

Aboveground dry weight

0.0000

0.3398

1.0000

0.1359

Belowground fresh weight

0.0000

0.4675

1.0000

0.6250

Belowground dry weight

0.0001

0.3572

1.0000

0.7286

Net photosynthetic rate (Pn)

0.0000

0.3222

1.0000

0.9561

Stomatal conductance (Gs)

0.0000

0.8138

1.0000

0.7698

Intercellular CO₂ concentration (Ci)

0.0000

1.0000

0.9211

0.3833

Transpiration rate (Tr)

0.0000

0.6232

0.7968

1.0000

Stomatal limiting value (Ls)

1.0000

0.0001

0.0790

0.6168

Chl a

0.0000

0.5884

0.9715

1.0000

Chl b

0.0000

0.7815

1.0000

0.7589

Total chl

0.0000

0.6650

1.0000

0.9381

Carotenoid content

0.0001

0.8374

0.6123

1.0000

Electrical conductivity %

1.0000

0.0000

0.0630

0.8727

Free proline content

0.3668

1.0000

0.3920

0.0000

Malondialdehyde content (MDA)

1.0000

0.5541

0.2970

0.0000

Soluble protein content

1.0000

0.6737

0.4044

0.0000

Soluble sugar content

0.0723

0.0001

0.7956

1.0000

POD activity

0.2593

0.0000

1.0000

0.7423

SOD activity

0.0000

0.1676

1.0000

0.9059

CAT activity

0.6890

1.0000

0.7495

0.0000

Aboveground Cd content

0.7308

0.8709

0.0000

1.0000

Belowground Cd content

0.8130

0.5528

0.0000

1.0000

Transport coefficient

0.0706

0.6067

1.0000

0.0001

Comprehensive evaluation of D value

− 0.5967

1.3155

2.4547

1.0992

Ranking

4

2

1

3