Table 1 Variance analysis of regression models fitting the indices related to dry weight, chlorophyll content and physiological properties.

Model

5

741.39^**

2

1.17^*

5

0.08^*

2

1.83^*

5

33.01^**

2

3.35^**

5

21.38^**

X₁ (Drought)

1

2694.05^**

1

1.77^*

1

0.15^*

1

2.97^*

1

130.28^**

1

6.54**

1

38.2^**

X₂ (Melatonin)

1

225.73^*

1

1.42^*

1

0.07^*

1

1.67^*

1

36.39^*

1

2.63^*

1

14.77^*

X₁×X₂

1

16.93^ns

-

-

1

0.01^ns

-

-

1

0.17^ns

-

-

1

2.07^ns

X₁²

1

0.07^ns

-

-

1

0.08^ns

-

-

1

15.99^ns

-

-

1

68.6^**

X₂²

1

651.22^*

-

-

1

0.23^**

-

-

1

26.36^*

-

-

1

45.27^**

Residuals

7

87.07

10

0.21

7

0.01

10

0.38

7

3.87

10

0.11

7

2.62

Lack of fit

3

177.52^*

6

0.32^ns

3

0.04^**

6

0.60^*

3

8.67^**

6

0.17^*

3

4.44^ns

Pure Error

4

19.23

4

0.05

4

0.00

4

0.06

4

0.27

4

0.01

4

1.26

R²

0.85

-

0.51

-

0.77

-

0.48

-

0.85

-

0.85

-

0.85

-

Adjusted R²

0.75

-

0.42

-

0.61

-

0.38

-

0.75

-

0.82

-

0.74

-

Predicted R²

0

-

0

-

0

-

0

-

0

-

0.69

-

0.06

-