Table 4 Correlation coefficients among sweetpotato NUEs and N uptake in four N treatments.

Index		Yield	AEN	REN	PEN	PFPN
N uptake of storage root	30–50 DAT	–0.022	0.271	0.221	0.305	0.091
	50–70 DAT	0.413	0.420	0.399	0.425	0.227
	70–90 DAT	0.769^**	0.393	0.461	0.295	0.448
	90–120 DAT	0.802^**	0.804^**	0.830^**	0.699^*	0.870^**
	Total	0.981^**	0.881^**	0.913^**	0.775^**	0.871^**
	N_max	0.932^**	0.930^**	0.943^**	0.832^**	0.897^**
	V_t	–0.050	0.350	0.317	0.339	0.262
	T	0.648^*	0.282	0.318	0.239	0.315
N uptake of whole plant	0–30 DAT	0.258	0.215	0.121	0.267	0.055
	30–50 DAT	0.744^**	0.324	0.423	0.211	0.415
	50–70 DAT	0.703^*	0.577^*	0.653^*	0.444	0.724^**
	70–90 DAT	0.894^**	0.587^*	0.638^*	0.481	0.639^*
	90–120 DAT	0.628^*	0.597^*	0.618^*	0.512	0.505
	Total	0.977^**	0.691^*	0.790^**	0.546	0.770^**
	N_max	0.783^**	0.596^*	0.594^*	0.526	0.557
	V_t	–0.042	–0.012	–0.089	0.034	–0.114
	T	0.782^**	0.595^*	0.592^*	0.526	0.554

DAT: Days after transplanting; N_max: Asymptotic maximum N uptake; V_t: Average N uptake rate during the fast N uptake period; T: The fast uptake period of sweetpotato N; ^*significant at P < 0.05; ^**significant at P < 0.01.

Quick links

Search