Table 2.

Soil type, soil S content (mg S kg⁻¹), S and N fertilization managed by the farmers (kg S or N ha⁻¹) and the value of the ([Cl]+[P]):[S] ratio in mature leaves harvested before or after fertilization in four oilseed rape commercial varieties from field experiment 2 (crops # 36′, 20′, 11′, and 8′). Status of plots have been determined within three groups (S deficient, at risk of S deficiency and S sufficient) according to threshold values of the ([Cl]+[P]):[S] ratio. Data are given as mean ± SE (n = 3). *, ** and *** indicate significant difference before and after fertilization for p < 0.05, p < 0.01 and p < 0.001, respectively. Letters when different indicate significant differences between crops at a given date, at p < 0.05.

			Before Flowering and Fertilization		S-(N) Fertilization (kg S-(N) ha−1	After Flowering and Fertilization
Plots number	Soil type	Soil S content (mg kg−1)	([Cl]+[P])/[S] ratio	Status of plots		([Cl]+[P])/[S] ratio	Status of plots
36′	Compact silt	136	3.72 ± 0.43 b	S deficient	10-(166)	1.54 ± 0.21 b**	S deficient
20′	Superficial clay-limestone	239	2.64 ± 0.13 c	Risk of S deficiency	100-(146)	0.59 ± 0.10 a***	S sufficient
11′	Superficial clay-limestone	350	1.99 ± 0.14 a	S sufficient	0-(110)	1.42 ± 0.05 b**	S deficient
8′	deep clay-limestone	668	1.80 ± 0.06 a	S sufficient	15-(151)	1.41 ± 0.24 b	S deficient