Relationship between spring triticale physiological traits and productivity changes as affected by different N rates

Figures & data

Table 1. Grain yield and protein content of spring triticale as affected by year and N fertilization.

	Grain yield (mg ha^−1)	Protein (%)
Year
2008	4.69 b^†	13.9 a^†
2009	4.54 c	13.5 a
2010	4.52 c	13.1 a
2011	5.11 a	11.4 a
Trial mean	4.72
N fertilization
N0	3.59 b^‡	11.4 b^‡
N60	4.53 a	12.0 a
N90	4.81 a	12.5 a
N120	4.92 a	13.0 a
N150	4.93 a	13.7 a
N180	5.09 a	13.9 a

Note: ^†Different letters in column denote a statistically significant difference (P ≤ .05) between years’ mean and trial mean.

^‡Different letters in column denote a statistically significant difference between fertilized treatments and unfertilized treatment (P ≤ .05).

Table 2. Physiological traits of spring triticale as affected by year and N fertilization.

Growth stage		SPAD^†	LAI	LAD	CGI
BBCH‡ 31	Year
	2008	44.6 b^§	1.06 c^§	–	44.6 c^§
	2009	41.5 c	2.26 a	–	96.7 a
	2010	50.2 a	1.75 b	–	74.1 b
	2011	41.6 c	1.69 b	–	73.1 b
	Trial mean	44.5	1.69	–	72.1
	N fertilization
	(1) N0	40.0 b^¶	1.13 b^¶	–	43.1 b^¶
	(2) N60	45.4 a	1.51 a	–	67.3 a
	(3) N90	44.7 a	1.77 a	–	76.9 a
	(4) N120	46.4 a	1.69 a	–	71.1 a
	(5) N150	45.7 a	1.81 a	–	76.6 a
	(6) N180	44.9 a	2.14 a	–	91.3 a
BBCH 45	Year
	2008	44.1 c^§	1.72 c	0.23 c	77.1 c
	2009	44.9 c	2.82 c	0.42 a	126.8 c
	2010	49.4 a	3.91 a	0.31 a	195.1 a
	2011	49.2 a	4.76 a	0.23 c	234.9 a
	Trial mean	46.9	3.30	0.30	158.5
	N fertilization
	(1) N0	41.8 b^¶	2.19 b	0.20 b	90.8 b
	(2) N60	46.4 a	3.28 a	0.29 a	150.3 a
	(3) N90	47.7 a	3.12 a	0.29 a	149.8 a
	(4) N120	49.2 a	3.45 a	0.31 a	175.7 a
	(5) N150	47.3 a	3.27 a	0.31 a	161.6 a
	(6) N180	48.1 a	3.90 a	0.37 a	193.3 a
BBCH 59	Year
	2008	52.2 b^§	2.30 c	0.13 c	120.8 c
	2009	51.5 b	2.65 c	0.34 c	136.8 c
	2010	51.4 b	4.39 a	0.38 c	220.2 a
	2011	53.2 a	2.98 b	0.97 a	160.6 b
	Trial mean	52.1	3.08	0.45	159.6
	N fertilization
	(1) N0	46.7 b^¶	1.97 b	0.28 b	95.8 b
	(2) N60	51.4 a	3.00 a	0.45 a	151.1 a
	(3) N90	52.3 a	3.46 a	0.47 a	178.2 a
	(4) N120	52.7 a	3.35 a	0.49 a	176.2 a
	(5) N150	54.7 a	3.18 a	0.45 a	169.4 a
	(6) N180	54.5 a	3.82 a	0.54 a	206.2 a
BBCH 69	Year
	2008	56.2 a^§	1.53 c	0.10 c	85.4 c
	2009	52.6 b	2.41 b	0.13 c	127.9 b
	2010	52.0 c	3.38 a	0.56 a	173.7 a
	2011	53.4 b	2.51 b	0.20 c	138.4 b
	Trial mean	53.6	2.46	0.24	131.4
	N fertilization
	(1) N0	47.7 b^¶	1.50 b	0.18 b	69.4 b
	(2) N60	51.3 a	2.36 a	0.25 a	122.5 a
	(3) N90	54.9 a	2.41 a	0.25 a	133.6 a
	(4) N120	54.5 a	2.76 a	0.28 a	144.9 a
	(5) N150	55.5 a	2.78 a	0.25 a	151.2 a
	(6) N180	55.3 a	2.88 a	0.28 a	158.3 a

Note: ^†SPAD – chlorophyll index, LAI – leaf area index, LAD – leaf area duration, CGI – canopy greenness index.

^‡BBCH-scale is a system for a uniform coding of phenologically similar growth stages of all mono- and dicotyledonous plant species.

^§Different letters in column denote a statistically significant difference (P ≤ .05) between years’ mean and trial mean.

^¶Different letters in column denote a statistically significant difference between fertilized treatments and unfertilized treatment (P ≤ .05).

Table 3. Mean squares (percentage of the sum of squares between parentheses) and significant effects of year and N rates on grain yield and grain protein in spring triticale over 4 years.

Source	df	Grain yield (mg ha^–1)	Grain protein (%)
Year (Y)	3	2.410** (13.4)	37.2** (44.1)
N fertilization (N)	5	3.720** (48.4)	15.8** (43.5)
Y × N	15	0.310** (12.2)	0.74** (6.1)

*Significant at the.05 probability level.

**Significant at the .01 probability level.

Table 4. Mean squares (percentage of the sum of squares between parenthesis) and effects of year, N rates and their interaction on physiological indices of spring triticale over 4 years.

Source	df	SPAD^†	LAI	LAD	CGI
BBCH 31^‡
Year (Y)	3	531.4** (49.6)	7.70** (43.7)	–	14564** (39.9)
N rate (N)	5	62.0** (13.5)	1.32** (17.5)	–	2984** (19.1)
Y × N	15	10.0 (6.5)ns§	0.41** (16.1)	–	817** (15.7)
BBCH 45^‡
Year (Y)	3	244.8** (31.7)	55.72** (58.1)	0.264** (52.8)	157987** (61.1)
N rate (N)	5	79.1** (23.9)	5.14** (12.5)	0.039** (18.1)	16205** (14.6)
Y × N	15	17.8** (16.1)	1.27** (9.3)	0.007** (9.4)	3330** (9.0)
BBCH 59^‡
Year (Y)	3	22.0* (3.4)	27.0** (33.7)	4.157** (84.3)	60800** (27.5)
N rate (N)	5	101.3** (38.3)	5.0** (14.5)	0.099** (4.6)	17739** (18.7)
Y × N	15	19.3** (21.9)	1.4* (12.6)	0.033** (4.7)	4601** (14.5)
BBCH 69^‡
Year (Y)	3	110.1** (11.5)	18.3** (39.3)	1.459** (85.4)	42369** (31.4)
N rate (N)	5	120.8** (29.5)	3.0** (15.2)	0.021** (2.9)	12042** (20.8)
Y × N	15	20.9 (15.3)ns	1.0** (15.4)	0.011** (4.6)	3055** (15.9)

Note: ^†SPAD – chlorophyll index, LAI – leaf area index, LAD – leaf area duration, CGI – canopy greenness index.

^‡BBCH-scale is a system for a uniform coding of phenologically similar growth stages of all mono- and dicotyledonous plant species.

*Significant at the.05 probability level.

**Significant at the.01 probability level.

§ns – nonsignificant.

Table 5. The correlation between spring triticale grain yield, grain protein and physiological indices for 2008–2011.

	Growth stage	SPAD^†	LAI	LAD	CGI
Grain yield	BBCH^‡ 31	0.252*	0.361**	–	0.401**
	BBCH 45	0.488**	0.437**	0.149	0.491**
	BBCH 59	0.460**	0.123	0.513**	0.176
	BBCH 69	0.406**	0.265*	0.018	0.334**
Grain protein	BBCH 31	0.183	0.147	–	0.141
	BBCH 45	0.049	−0.308*	0.375**	−0.267*
	BBCH 59	0.248*	0.072	−0.502**	0.083
	BBCH 69	0.272*	0.018	−0.055	0.057

*Significant at the.05 probability level.

**Significant at the.01 probability level.

^†SPAD – chlorophyll index, LAI – leaf area index, LAD – leaf area duration, CGI – canopy greenness index.

Table 6. The path coefficients analysis showing direct and indirect effects of the physiological indices on grain yield of spring triticale.

		Effects via								Grain
		SPAD (1)		LAI (2)		LAD (3)		CGI (4)		yield
BBCH^†	Indices^‡	PC§	%^¶	PC	%	PC	%	PC	%	r Y
31	SPAD (1)	0.082^#	14.0	−0.167	28.4	–	–	0.338^††	57.6	0.252*
	LAI (2)	0.022	1.4	−0.625	38.8	–	–	0.963	59.8	0.361**
	CGI (4)	0.028	1.7	−0.611	37.6	–	–	0 . 984	60.6	0.401**
45	SPAD (1)	0.210	23.0	−0.213	23.4	0.004	0.4	0.485	53.2	0.487**
	LAI (2)	0.101	7.6	−0.445	33.5	0.022	1.7	0.759	57.2	0.437**
	LAD (3)	0.012	2.9	−0.136	32.4	0.072	17.1	0.200	47.6	0.149
	CGI (4)	0.132	9.7	−0.435	32.0	0.019	1.4	0 . 775	56.9	0.491**
59	SPAD (1)	0.483	37.6	0.254	19.7	0.137	10.6	−0.414	32.1	0.460**
	LAI (2)	0.162	18.2	0.759	38.4	0.130	6.6	−0.928	46.9	0.123
	LAD (3)	0.144	12.8	0.216	19.3	0 . 457	40.7	−0.305	27.2	0.513**
	CGI (4)	0.213	10.4	0.751	36.6	0.149	7.3	− 0 . 937	45.7	0.176
69	SPAD (1)	0 . 283	69.5	0.006	1.5	0.037	9.1	0.081	19.9	0.406**
	LAI (2)	−0.008	0.8	−0.216	21.1	−0.155	15.2	0.644	63.0	0.265*
	LAD (3)	−0.048	5.6	−0.156	18.2	−0.215	25.1	0.437	51.1	0.018
	CGI (4)	0.035	3.3	−0.212	20.3	−0.143	13.7	0 . 655	62.7	0.334**

Note: ^†BBCH-scale is a system for a uniform coding of phenologically similar growth stages of all mono- and dicotyledonous plant species.

^‡SPAD – chlorophyll index, LAI – leaf area index, LAD – leaf area duration, CGI – canopy greenness index.

^§PC – Path coefficient.

^¶% – percentage of direct and indirect effects.

^#Values in italics mean direct effects.

^††Underlined values mean dominant effects.

*Significant at the .05 probability level.

**Significant at the .01 probability level.

Table 7. The Path coefficient analysis showing direct and indirect effects of the physiological indices on grain protein of spring triticale.

		Effects via
		SPAD (1)		LAI (2)		LAD (3)		CGI (4)		Protein
BBCH^†	Indices^‡	PC§	%^¶	PC	%	PC	%	PC	%	r Y
31	SPAD (1)	0.191 #	40.6	0.136	28.9	–	–	−0.144	30.5	0.183
	LAI (2)	0.051	5.3	0 . 507	52.3	–	–	−0.411	42.4	0.147
	CGI (4)	0.066	6.7	0.496††	50.5	–	–	−0.420	42.8	0.141
45	SPAD (1)	0.179	14.4	−0.597	48.0	0.033	2.7	0.434	34.9	0.049
	LAI (2)	0.086	3.9	− 1 . 246	57.1	0.173	7.9	0.678	31.1	−0.308*
	LAD (3)	0.010	8.8	−0.382	33.6	0 . 566	49.8	0.179	15.7	0.375**
	CGI (4)	0.112	5.2	−1.219	56.2	0.146	6.7	0.693	31.9	−0.267*
59	SPAD (1)	0 . 488	38.7	0.267	21.2	−0.192	15.1	−0.315	25.0	0.248*
	LAI (2)	0.164	8.9	0 . 798	43.1	−0.183	9.9	−0.706	38.1	0.072
	LAD (3)	0.146	11.7	0.227	18.2	− 0 . 643	51.5	−0.232	18.6	−0.502**
	CGI (4)	0.216	11.2	0.790	41.0	−0.209	10.8	−0.714	37.0	0.083
69	SPAD (1)	0 . 305	84.0	−0.010	2.8	0.012	3.3	−0.036	9.9	0.272*
	LAI (2)	−0.008	1.1	0 . 361	51.2	−0.051	7.2	−0.284	40.3	0.018
	LAD (3)	−0.052	9.0	0.260	45.1	−0.071	12.3	−0.193	33.5	−0.055
	CGI (4)	0.038	5.2	0.355	48.7	−0.047	6.4	−0.289	39.6	0.057

Note: ^†BBCH-scale is a system for a uniform coding of phenologically similar growth stages of all mono- and dicotyledonous plant species.

^‡SPAD – chlorophyll index, LAI – leaf area index, LAD – leaf area duration, CGI – canopy greenness index.

^§PC – path coefficient.

^¶% – percentage of direct and indirect effects.

^#Values in italics mean direct effects.

^††Underlined values mean dominant effects.

*Significant at the .05 probability level.

**Significant at the .01 probability level.