. 2020 Sep 2;11:1307. doi: 10.3389/fpls.2020.01307

Table 3.

Effects of year, cultivar, and levels of NPK on nitrogen accumulation (kg ha^–1) in different plant organs at different growth stages and on nitrogen harvest index of maize.

Treatments	At silking				At physiological maturity					Post-silking N accumulation	HI(N)^†
	Leaf	Stalk		Total	Leaf	Stalk		Grain	Total
	Leaf	Stem	Tassel	Total	Leaf	Stem	Other	Grain	Total
Year
Year 1	51.5a	55.6a	7.66a	114.8a	44.2b	15.6b	9.21a	114.8a	183.8b	69.0b	0.64a
Year 2	51.6a	54.8b	7.68a	114.1a	52.4a	22.0a	9.20a	118.2a	201.8a	87.7a	0.58b
Cultivar
P3522	63.3a	59.4a	3.9c	126.7a	49.6a	14.7c	7.2b	122.2a	193.7a	67.0b	0.63a
P3396	42.9c	54.6b	7.4b	105.0c	47.7a	18.7b	10.3a	118.6a	195.4a	90.4a	0.61a
Rajkumar	48.3b	51.7b	11.7a	111.7b	47.6a	23.0a	10.1a	108.7b	189.4a	77.8ab	0.58a
Levels of NPK
N₁₀₀P₃₀K₃₀ (50% RDF)	49.6e	42.2e	6.8ef	98.5d	50.0cd	15.8de	8.0d	118.1cd	191.8e	93.3bc	0.61ab
N₁₅₀P₄₅K₄₅ (75% RDF)	58.1cd	55.7d	8.0cd	121.9c	53.7bc	18.7d	10.1c	129.3bc	211.9d	90.0bc	0.61ab
N₂₀₀P₆₀K₆₀ (100% RDF)	64.8ab	71.6c	8.9bc	145.2b	60.0b	23.2c	11.6b	144.3ab	239.1c	93.9bc	0.60ab
N₂₅₀P₇₅K₇₅ (125% RDF)	68.8a	80.1b	9.3a	158.2a	67.9a	29.8b	12.0b	149.6a	259.2b	101.0ab	0.58ab
N₃₀₀P₉₀K₉₀ (150% RDF)	60.7bc	90.3a	9.6a	160.6a	70.3a	41.7a	14.0a	153.3a	279.2a	118.6a	0.55b
P₆₀K₆₀ (100% RDF–N)	28.2f	25.0f	5.9fg	59.1e	29.5e	8.7gh	6.3e	62.7e	107.2g	48.2d	0.59ab
N₂₀₀K₆₀ (100% RDF–P)	57.7cd	56.0d	8.3bc	122.1c	45.7d	13.7ef	8.3d	129.8bc	197.4de	75.4c	0.66a
N₂₀₀P₆₀ (100% RDF–K)	54.1de	57.6d	7.1de	118.7c	36.4e	10.7fg	7.5d	107.4d	161.9f	43.2d	0.66a
Control (–NPK)	21.7g	18.8g	5.2g	45.7f	21.2f	7.0h	5.1f	54.1e	87.5h	41.8d	0.62ab
Source of variation
Year	ns	*	ns	ns	*	**	ns	ns	*	**	**
Cultivar	**	*	**	**	ns	**	**	*	ns	*	ns
Levels of NPK	**	**	**	**	**	**	**	**	**	**	**
Year × cultivar	ns	*	ns	ns	*	*	ns	ns	ns	ns	*
Year × levels of NPK	ns	*	ns	ns	ns	*	ns	ns	ns	ns	ns
Cultivar × levels of NPK	**	**	ns	**	ns	**	**	ns	ns	ns	ns
Year × cultivar × levels of NPK	ns	*	ns	ns	ns	ns	ns	ns	ns	ns	ns

Year 1 and year 2 represent winter 2012–13 and 2013–14, respectively. Within year, cultivar, and levels of NPK, numbers followed by different letters indicate significant differences at p ≤ 0.05 (otherwise statistically at par). ns, non-significant (p > 0.05). *Significant at p ≤ 0.05. **Significant at p ≤ 0.01; Other = Tassel + cob + shank + husk; ^†HI (N), Harvest Index (Nitrogen)