Table 4.

Correlation analysis of growing conditions and antioxidant properties and phenolics for two tartary buckwheat varieties grown in 3 locations.

Environment	Variety	Antioxidant property and phenolic content
parameter		DPPH	AACF	AACB	TPC	TFC	TPA	R	Q	HA	FA	PA
MT (°C)	XK	−0.72	−0.22	−0.26	0.80	0.56	−0.56	−0.50	−0.98 *	−0.99 *	0.25	−0.29
	DQ	0.13	0.46	0.91	−0.61	−0.32	−0.83	−0.78	0.64	−0.73	−0.76	−0.65
AOP (mm)	XK	0.85	0.98 *	0.99 *	0.38	−0.94	0.94	0.96 *	0.06	0.23	0.88	0.99 *
	DQ	0.93	0.75	−0.63	−0.62	−0.84	0.74	0.79	−0.90	0.84	0.82	−0.58
SH (h)	XK	−0.98 *	−0.57	−0.75	0.34	0.92	−0.93	−0.90	−0.72	−0.83	−0.33	−0.77
	DQ	−0.44	−0.11	0.99 *	−0.07	0.25	−0.99 *	−0.99 *	0.96 *	−0.99 *	−0.99 *	−0.12
A (m)	XK	0.99 *	0.77	0.9	−0.07	−0.99 *	0.99 *	0.98 *	0.51	0.64	0.57	0.91
	DQ	0.67	0.37	−0.91	−0.2	−0.51	0.97 *	0.98 *	−0.99 *	0.99 *	0.99 *	−0.15

Results expressed as Pearson correlation coefficients with indicated level of significance. Data with asterisks were significant at P < 0.05. XK, Xingku No.2; DQ, Diqing; MT, mean temperature; AOP, amount of precipitation; SH, sunlight hours; A, altitude; DPPH, DPPH^● scavenging activity; AAC_F, antioxidant activity coefficient of free phenolics; AAC_B, antioxidant activity coefficient of bound phenolics; TPC, total phenolic content; TFC, total flavonoid content; TPA, total phenolic acid ; R, rutin; Q, quercetin; HA, p-Hydroxybenzoic acid; FA, Ferulic acid; PA, Protocatechuic acid.