Fusarium head blight and deoxynivalenol contamination in wheat as affected by nitrogen fertilization

Figures & data

Table 1 Treatments at the two experimental sites including the soil amendments used for basal dressing, top-dressing materials, N-dose(s) applied at anthesis and NDICEA-calculated plant available nitrogen (PAN) values for each treatment.

Location	Soil amendment system		Top-dressing treatment			Total
	Calculated PAN (kg N ha^−1)		Application (kg N ha^−1)	Calculated PAN (kg N ha^−1)		Calculated PAN (kg N ha^−1)
	2006	2007		2006	2007	2006	2007
Colijns-plaat	Slurry		Control
	161	146	0	0	0	161	146
			Pellets
	161	146	65 (65)	28	35	189	181
	161	146	105 (65 + 40)	43	55	204	201
			Molasses
	161	146	108(108)	31	35	192	181
	161	146	175 (108 + 67)	48	57	209	203
	Compost		Control
	205	203	0	0	0	205	203
			Pellets
	205	203	65 (65)	28	35	233	238
	205	203	105 (65 + 40)	43	55	248	258
			Molasses
	205	203	108(108)	31	35	236	238
	205	203	175 (108 + 67)	48	57	253	260
Zeewolde	Farmyard manure		Control
	109	129	0	0	0	109	129
			Pellets
	109	129	65 (65)	21	24	130	153
	109	129	105 (65 + 40)	31	38	140	167
			Molasses
	109	129	108(108)	27	25	136	154
	109	129	175 (108 + 67)	42	46	151	175

Fig. 1 Grain-nitrogen content versus NDICEA-calculated plant available nitrogen for the basal fertilizer treatments in 2006 and 2007. S = slurry; C = compost; F = farmyard manure.

Table 2 Effect of experimental treatments on grain yield and straw dry matter accumulation during the 2006 and 2007 growing season for the three different soil amendment systems. Means in the same column, followed by a different lower cast letter are statistically different (p < 0.05).

Location	Soil amendment system	Top-dressing treatment application (kg ha^−1)	Crop performance
			Grain yield (kg ha^−1)		Straw yield (kg N ha^−1)
			2006	2007	2006	2007
Colijnsplaat	Slurry	Control
		0	8070a	2723a	4620b	2875b
		Pellets
		65 (65)	8017a	2736a	5379a	3229a
		105 (65 + 40)	8022a	2808a	5446a	3667a
		Molasses
		108(108)	7830a	2713a	5274a	3708a
		175 (108 + 67)	7328b	2672a	5132ab	3917a
	Compost	Control
		0	7617a	2794a	4656ab	3708ab
		Pellets
		65 (65)	7965a	2862a	5180a	3375b
		105 (65 + 40)	6984a	2901a	4947a	3688ab
		Molasses
		108(108)	7873a	2849a	4481b	3521ab
		175 (108 + 67)	7435a	2761a	5005ab	4375a
Zeewolde	Farmyard manure	Control
		0	3605c	3730a	1303c	1309b
		Pellets
		65 (65)	4588b	3045a	1900b	1382b
		105 (65 + 40)	4543b	3396a	1873b	1814b
		Molasses
		108(108)	5838a	3032a	2411a	2196ab
		175 (108 + 67)	4910b	3126a	2369a	3106a

Table 3 Summary statistics (mean, median, minimum and maximum) of the FHB infected seeds (% of all seeds) measured in a blotter test, and the DON contents in the years 2006 and 2007.

	Mean	Median	Min.	Max.
FHB infected seeds (%)
2006	2.7	2.3	0	12.0
2007	16.8	17.0	9.3	22.3
DON (μg kg^−1)
2006	159	136	45	363
2007	438	428	99	794

Table 4 Results of the ANOVA on the percentage of FHB infected seeds. No statistically significant interactions were found, but between years and between the top-dressing treatments differences were statistically significant as indicated by different lower cast letters following the means (p < 0.05).

	Mean	p-Value
FHB infected seeds (%)
2006	2.7a	<0.001
2007	16.8b
Basal fertilizer treatment
Slurry	9.5a	0.577
Compost	9.7a
Farmyard manure	10.1a
Top-dressing
Control	8.2a	0.002
Pellets 65	9.6b
Pellets 105	10.4bc
Molasses 108	9.6ab
Molasses 175	11.1c

Table 5 Results of the ANOVA on log₁₀DON contents. There was a statistically significant interaction between top-dressing treatment and year, and there were statistically significant differences between years and between basal fertilizer dressings. The other interactions were not statistically significant. Means within the main factors, followed by a different lower cast letter are statistically different (p < 0.05).

	Mean		p-Value
Log10DON (log10 μg kg^−1)
2006	2154a		<0.001
2007	2612b
Basal fertilizer treatment
Slurry	2459b		0.004
Compost	2343a
Farmyard manure	2348a
Year × top-dressing			0.023
	2006	2007
Control	1999a	2652d
Pellets 65	2179b	2608d
Pellets 105	2136b	2571d
Molasses 108	2172b	2626d
Molasses 175	2284c	2605d

Fig. 2 Deoxynivalenol (DON) content of wheat grain in 2006 in relation to grain-nitrogen content for the slurry [S] and compost [C] treatments at the Colijnsplaat site (A) and for the farmyard manure treatments (F) at the Zeewolde site (B). Deoxynivalenol (DON) content of wheat grain in 2006 in relation to straw dry matter production for the slurry [S] and compost [C] amended treatments at the Colijnsplaat site (C) and for the farmyard manure amended treatments [F] at the Zeewolde site (D). The dotted line indicates the absence of relatively high DON contents at low grain-N contents (A) and at low straw dry matter production (C).

Fig. 3 Deoxynivalenol (DON) content of wheat grain in 2007 in relation to grain-nitrogen content for the slurry [S] and compost [C] amended treatments at the Colijnsplaat site (A) and for the farmyard manure amended treatments [F] at the Zeewolde site (B). Deoxynivalenol (DON) contents of wheat grain in 2006 in relation to straw dry matter production for the slurry [S] and compost [C] amended treatments at the Colijnsplaat site (C) and for the farmyard manure amended plots [F] at the Zeewolde site (D).

Fig. 4 Relation between NDICEA-calculated plant available nitrogen (PAN) and weed infestation score for slurry-based (S) and compost-based (C) treatments during the 2007 growing season. Different series represent the two soil × fertilizer systems. The solid and the broken line are the regression lines, both being statistically significant (S: p < 0.001; C: p = 0.0015).

Fig. 5 Weed infestation score against grain-nitrogen content for the slurry-based (S) and compost-based (C) treatments during the 2007 growing season.