Determining Critical Soil pH for Grain Sorghum Production

Table 4

Results from quadratic least squares regression when evaluating the effect of soil pH on grain sorghum relative yield (2009 and 2010).

	DF	Mean square	𝐹	Prob 𝐹	𝑟^2
2009
Lahoma	2	0.06	2.31	0.133	0.24
Perkins	2	0.04	0.35	0.7082	0.04
All locations	2	0.18	3.23	0.0542	0.18
2010
Lahoma	2	0.06	1.59	0.2371	0.17
Perkins	2	1.24	37.67	<0.0001	0.83
Haskell	2	0.25	15.65	0.0002	0.68
All locations	2	1.12	22.82	<0.0001	0.47