Table 6 Average values of biological yield, straw yield, grain yield, protein content and potassium content (K) of maize hybrid “Pioneer SC-30N11” as affected by compost, the potassium fertilization forms and their interaction during two seasons (2017 and 2018).

Biological yield (ton/ha)

Untreated (No- K)

13.2

15.0

15.9

14.7d

0.18

0.59

1.2

13.3

14.7

15.3

14.4c

0.19

0.52

1.0

Nano-potassium (K)

14.7

16.7

16.9

16.1a

14.7

16.7

16.7

16.0a

Humic acid (HA)

14.4

16.3

16.5

15.7b

14.1

16.4

17.3

15.9a

Potassium sulfate (K₂SO₄)

14.7

16.5

15.4

15.5c

14.8

16.5

15.6

15.6b

14.3b

16.1a

16.2a

14.2b

16.1a

16.3a

Straw yield (ton/ha)

Untreated (No- K)

8.1

9.0

9.3

8.8 c

0.22

0.36

0.72

8.2

8.8

9.1

8.7c

0.33

0.37

0.74

Nano-potassium (K)

8.7

9.5

9.9

9.4 a

8.7

9.8

9.9

9.5a

Humic acid (HA)

8.4

9.4

9.7

9.2 b

8.0

9.6

10.1

9.2a

Potassium sulfate (K₂SO₄)

8.5

9.7

9.0

9.1 b

8.6

9.8

9.1

9.1b

8.4b

9.4a

9.5a

8.4b

9.5a

9.6a

Grain yield (ton/ha)

Untreated (No- K)

5.1

6.0

6.6

5.9 c

0.14

0.39

0.78

5.1

5.9

6.2

5.7 c

0.26

0.31

0.62

Nano-potassium (K)

6.0

7.2

7.0

6.7 a

6.0

6.9

6.8

6.6 a

Humic acid (HA)

6.0

6.9

6.8

6.6 a

6.1

6.8

7.3

6.8 a

Potassium sulfate (K₂SO₄)

6.2

6.8

6.4

6.5 b

6.2

6.7

6.4

6.4 b

5.8 b

6.7 a

6.7 a

5.9 b

6.6 a

6.8 a

Protein content (%)

Untreated (No- K)

6.7

7.9

8.9

7.8d

6.2

8.3

9.3

7.9c

Nano-potassium (K)

7.6

9.3

10.0

9.0a

0.38

0.47

0.18

7.6

9.2

9.6

8.8a

0.20

0.45

0.77

Humic acid (HA)

7.5

8.5

9.3

8.4b

7.7

8.9

9.7

8.8a

Potassium sulfate (K₂SO₄)

7.1

8.7

8.3

8.0c

7.4

9.5

8.8

8.6b

7.2c

8.6b

9.1a

7.2b

9.0a

9.4a

K content (%)

Untreated (No- K)

1.2

1.1

1.3

1.2c

1.2

1.5

1.6

1.4c

Nano-potassium (K)

1.3

2.0

1.7

1.7a

0.13

0.15

0.25

1.3

2.1

2.0

1.8a

0.13

0.19

0.33

Humic acid (HA)

1.4

1.2

1.8

1.5b

1.8

1.5

1.9

1.7a

Potassium sulfate (K₂SO₄)

1.1

1.3

1.6

1.3bc

1.4

1.6

1.6

1.5b

1.3c

1.4b

1.6a

1.4b

1.7a

1.8a