Table 6.

Pearson correlation matrix of nodule number, selected phytochemicals and rhizosphere soil properties of cowpea.

	pH	TN (%)	SOC	AvP	Nodule count	Flavonoids in soil
pH					0.70∗∗
TN (%)	0.84∗∗∗				0.92∗∗∗
SOC (g kg−1)	0.99∗∗∗	0.86∗∗∗			0.72∗∗
AvP (mg kg−1)	0.66∗∗	0.92∗∗∗	0.68∗∗		0.98∗∗∗
Flavonoid (soil)	0.71∗∗	0.93∗∗∗	0.73∗∗	0.95∗∗∗	0.97∗∗∗
Flavonoids (roots)	0.81∗∗∗	0.97∗∗∗	0.82∗∗∗	0.96∗∗∗	0.95∗∗∗	0.93∗∗∗
Phenols (soil)	0.70∗∗	0.93∗∗∗	0.71∗∗	0.98∗∗∗	0.98∗∗∗	0.96∗∗∗
Phenols (root)	0.83∗∗∗	0.94∗∗∗	0.84∗∗∗	0.89∗∗∗	0.88∗∗∗	0.83∗∗∗
AAS	0.11ns	0.32ns	0.09ns	0.32ns	0.19ns	0.23ns
Alkaloids soil	0.75	0.91∗∗∗	0.75∗∗	0.94∗∗∗	0.93∗∗∗	0.94∗∗∗
CEC	0.93∗∗∗	0.74∗∗	0.89∗∗∗	0.55∗	0.62∗	0.63∗
Saponins (leaves)	0.66∗∗	0.91∗∗∗	0.7∗∗	0.96∗∗∗
Saponins (root)	0.84∗∗∗	0.97∗∗∗	0.86∗∗∗	0.94∗∗∗
Taninns (leaves)	0.7∗∗	0.93∗∗∗	0.72∗∗	0.96∗∗∗
Tannins (root)	0.68∗∗	0.91∗∗∗	0.73∗∗	0.94∗∗∗
Antioxidant activity (leaves)	0.81∗∗∗	0.98∗∗∗	0.83∗∗∗	0.95∗∗∗
Antioxidant activity (roots)	0.75∗∗	0.90∗∗	0.79∗∗∗	0.87∗∗∗
Alkaloids (leaves)	0.75∗∗	0.87∗∗∗	0.74∗∗	0.87∗∗∗
Alkaloids (root)	0.81∗∗∗	0.94∗∗∗	0.82∗∗∗	0.94∗∗∗

AAS = antioxidant activity in soil, TN = total nitrogen, AvP = available phosphorus, SOC = soil organic carbon, CEC = cation exchange capacity, significant at; ∗ for 0.05, ∗∗ for 0.01 and ∗∗∗ for 0.001 probability level, ^ns = non significant.