Variable

Regression equation

R²

ZnRMTDW¹

1. Zn rate vs SDW of Sunn hemp

Y = 3.16 − 0.020X + 0.00022X²

0.16^NS

-

2. Zn rate vs SDW of smooth crotalaria

Y = 0.67 + 0.048X − 0.0012X²

0.86^**

20

3. Zn rate vs SDW of showy crotalaria

Y = 1.09 + 0.019X − 0.00056X²

0.80^**

16

4. Zn rate vs SDW of calopo

Y = 0.43 + 0.033X − 0.00051X²

0.73^**

32

5. Zn rate vs SDW of pueraria

Y = 0.58 + 0.023X − 0.00047X²

0.66^**

24

6. Zn rate vs SDW of pigonpea

Y = 1.16 + 0.061X − 0.00097X²

0.74^**

31

7. Zn rate vs SDW of lablab

Y = 3.71 + 0.429X − 0.0095X²

0.91^**

23

8. Zn rate vs SDW of black velvet bean

Y = 5.27 + 0.179X − 0.0036X²

0.81^**

25

9. Zn rate vs SDW of gray velvet bean

Y = 3.55 + 0.379X − 0.0106X²

0.83^**

18

10. Zn rate vs SDW of jack bean

Y = 7.94 + 0.169X − 0.0034X²

0.83^**

25

Average of 10 cover crops

Y = 2.75 + 0.132X − 0.0031X²

0.90^**

22