Table 2.

Two-way analysis of variance (ANOVA) for the indicators studied in the shoot/leaf and root of maize inbred line TX-40 J under different N treatments

Trait/(plant)	Sources of variation
	Shoot/leaf			Root
	Growth stage (S)	Treatment (T)	S x T	Growth stage (S)	Treatment (T)	S x T
	(df = 1)	(df = 3)	(df = 3)	(df = 1)	(df = 3)	(df = 3)
Biomass	0.0046**	0.0017**	0.5867 ns	0.0079**	0.0053**	0.0168*
Total biomass	0.0024**	0.0469*	0.1272 ns	0.4841 ns	0.0069**	0.0933 ns
Pn	0.0828 ns	0.0057**	0.6957 ns	n/a	n/a	n/a
Sucrose	0.3649 ns	0.00478**	0.6724 ns	0.001**	0.0065**	0.0761 ns
Nitrogen	0.0066**	0.0146*	0.5013 ns	0.0724 ns	0.0022**	0.2929 ns
Soluble sugar	0.0084**	0.0031**	0.1439 ns	0.0029**	0.0081**	0.0093**
Sucrose	0.3649 ns	0.0047**	0.6724 ns	0.001**	0.0065**	0.0761 ns
Starch	0.0021**	0.0032**	0.0677 ns	0.004**	0.0047**	0.3294 ns
Fructose	0.0522 ns	0.0125*	0.1901 ns	0.0381*	0.0086**	0.5235 ns
Glucose	0.5173 ns	0.0044**	0.1753 ns	0.2566 ns	0.0158*	0.3824 ns
Hexose	0.1592 ns	0.0008***	0.1495 ns	0.1522 ns	0.0007***	0.1695 ns
TNC	0.002**	0.0005***	0.1207 ns	0.0065**	0.0023**	0.1237 ns
H/S ratio	0.3255 ns	0.0101*	0.4445 ns	0.0151*	0.1462 ns	0.0469*
SPS	0.0084**	0.0031**	0.1439 ns	0.0147*	0.0062**	0.0315*
SuSy	0.0355*	0.0087**	0.7709 ns	0.0032**	0.0152*	0.5101 ns
AGPase	0.0064**	0.0563 ns	0.2363 ns	0.438 ns	0.0063**	0.2436 ns
CINV	0.1131 ns	0.003**	0.7025 ns	0.1801 ns	0.0073**	0.0445*
VINV	0.0438*	0.0115*	0.1266 ns	0.019*	0.0003***	0.0605 ns
CWINV	0.0005***	0.0162*	0.1512 ns	0.0011**	0.0057**	0.4607 ns
Amino acid	0.0209*	0.0005***	0.6194NS	0.0199*	0.0131*	0.1075 ns
Total protein	0.031*	0.0023**	0.7153 ns	0.0236*	0.0092**	0.0999 ns
TSUC	0.0201*	0.0036**	0.5331 ns	0.0078**	0.003**	0.0184*
ZmSuSy1	0.2054 ns	0.0195*	0.3628 ns	0.1572 ns	0.0154*	0.8374 ns
ZmSPS1	0.6194 ns	0.0183*	0.4934 ns	0.4353 ns	0.0384*	0.8592 ns
ZmCINV1	0.0387*	0.0169*	0.645 ns	0.673 ns	0.0011**	0.8434 ns
ZmVINV1	0.6256 ns	0.0097**	0.6616 ns	0.1943 ns	0.0482*	0.1635 ns
ZmCWINV1	0.0428*	0.009**	0.8617 ns	0.7135 ns	0.0074**	0.2518 ns
ZmAGPase1	0.0215*	0.0121*	0.3896 ns	0.3421 ns	0.0407*	0.1725 ns
ZmSUC2	0.0602 ns	0.0026**	0.7507 ns	0.0049**	0.0169*	0.6381 ns
ZmSWEET14	0.9827 ns	0.0582 ns	0.9378 ns	0.0119*	0.0225*	0.3619 ns
ZmSS1	0.0428*	0.009**	0.8617 ns	0.7137 ns	0.0074**	0.2518 ns
ZmAMY1	0.04644*	0.0183*	0.4934 ns	0.6441 ns	0.0016**	0.8302 ns
ZmBAM1	0.0253*	0.0074**	0.4297 ns	0.1206 ns	0.0370*	0.1709 ns
SS	0.0004***	< 0.0001****	0.0632 ns	0.01801**	0.0017**	0.1221 ns
AMY	0.0047**	< 0.0001***	0.0413*	0.011*	< 0.0001****	0.0919 ns
BAM	0.0449*	0.001**	0.0061**	0.0277*	0.0021**	0.5368 ns

R/S ratio root:shoot ratio; Pn net photosynthetic rate; H/S ratio hexose/sucrose ratio; SuSy sucrose synthase activity; CINV/ZmCINV1, cytoplasmic invertase activity; VINV/ZmVINV1, vacuolar invertase activity; SPS/ZmSPS1, sucrose phosphate synthase; AGPase/ZmAGPase1, ADP-glucose pyrophosphorylase; TSUC, total sucrolytic activity; TNC total non-structural carbohydrate; ns, non-significant; na non-applicable. In addition, *, **, and *** denote significance at probability levels of 0.05, 0.01, and 0.001, respectively. Tissue biomasses were quantified as g DW, net photosynthesis was quantified as [μmol (CO₂) m⁻² s⁻¹], while other indicators were quantified as (μmol/g DW)