Table 1 CLIMEX parameter values used for modelling the Climatic suitability of Spodoptera frugiperda, based on five published studies and the current study.

Temperature index (TI)

 DV0

Lower temperature threshold

°C

12

12

12

8.7

12

9.4

 DV1

Lower optimal temperature for growth

°C

22

25

25

24.6

25

26

 DV2

Upper optimal temperature for growth

°C

27

30

30

32

30

30

 DV3

Upper temperature threshold

°C

34

39

36

39.5

36

39.5

Moisture index (MI)

 SM0

Lower soil moisture threshold

0.1

0.15

0.15

0.15

0.15

0.1

 SM1

Lower optimal soil moisture

0.7

0.8

0.8

0.8

0.8

0.65

 SM2

Upper optimal soil moisture

0.9

1.5

1.5

1.5

1.5

1.5

 SM3

Upper soil moisture threshold

1.5

2.5

2

2.5

2.5

2

Cold stress (CS)

 TTCS

Cold stress temperature threshold

°C

8

12

8

8.7

8

9.4

 THCS

Cold stress accumulation rate

week^− 1

−0.00001

−0.001

−0.005

−0.001

−0.005

−0.003

Heat stress (HS)

 TTHS

Heat stress temperature threshold

°C

38

39

39

39.5

39

39.5

 THHS

Heat stress accumulation rate

week^− 1

0.001

0.005

0.0025

0.005

0.0025

0.005

Dry stress (DS)

 SMDS

Soil moisture dry stress threshold

0.1

0.1

0.1

0.1

0.1

0.1

 HDS

Dry stress accumulation rate

week^− 1

−0.001

−0.005

−0.005

−0.005

−0.005

−0.005

Wet stress (WS)

 SMWS

Soil moisture wet stress threshold

1.5

2.5

2

2.5

2.5

2

 HWS

Wet stress accumulation rate

week^− 1

0.001

0.002

0.01

0.002

0.001

0.01

Limiting conditions

 PDD

Length of growing season / Minimum degree day sum needed to complete a generation

°C days

559

600

400

559

391.61

392

 Other

 Irrigation

mm day^− 1

–

2.5

2.5

–

2.5

2.5