Cadmium and Zinc Concentration in Grain of Durum Wheat in Relation to Phosphorus Fertilization, Crop Sequence and Tillage Management

Table 4

Grain Cd concentration (μg kg⁻¹) and accumulation (mg ha⁻¹) of durum wheat as affected by tillage system, crop rotation, and P fertilization on at two sites over 3 years.

		Grain Cd concentration (μg kg^−1)								Grain Cd accumulation (mg ha^−1)
		BRC North				MZTRF				BRC North				MZTRF
		2001	2002	2003		2001	2002	2003		2001	2002	2003		2001	2002	2003
Tillage
Conventional		120.1	122.8	144.2		82.5	86.1	83.5		216	380	401		269	279	247
Reduced		120.4	70.1	119.8		81.8	61.3	99.8		228	205	380		267	221	289
LSD		9.1	13.9	15.9		4.8	8.7	11.3		20	48	80		18	31	37
Crop rotation
wheat-flax-durum		117.3	92.0	131.1		78.6	70.5	90.8		215	270	394		255	239	270
Canola-flax-durum		123.3	100.9	132.9		85.6	76.9	92.5		229	316	387		282	260	266
LSD		9.1	13.9	15.9		4.8	8.7	11.3		20	48	80		18	31	37
P fertilization
0-0-25		117.1	89.9	132.2		83.1	68.4	88.6		223	272	400		274	226	258
0-25-0		110.3	97.5	116.2		80.3	72.9	87.9		191	287	318		265	226	257
25-0-25		116.9	94.8	133.9		82.3	81.8	94.6		216	283	393		265	291	277
25-25-0		120.7	98.9	126.0		78.5	68.3	83.1		223	307	369		248	226	239
50-0-25		131.1	99.7	150.4		87.1	84.3	111.1		244	304	459		285	295	329
50-25-0		125.5	97.8	133.2		81.5	66.6	84.6		234	302	404		272	237	247
LSD		15.7	24.1	27.5		8.3	15.1	19.5		35	84	139		32	54	64
Analysis of variance
Source	DF							Pr ≥ F
Tillage	1	n.s.	<0.001	0.003		n.s.	<0.001	0.005		n.s.	<0.001	n.s.		n.s.	0.004	0.025
Crop rotation	1	n.s.	n.s.	n.s.		0.005	n.s.	n.s.		n.s.	n.s.	n.s.		0.005	n.s.	n.s.
P fertilization	5	n.s.	n.s.	n.s.		n.s.	n.s.	n.s.		n.s.	n.s.	n.s.		n.s.	0.014	n.s.