Nutritional composition of hazelnut (Corylus avellana L.) as influenced by basic fertilization

Figures & data

Table 1. Some soil properties before basic fertilizer applications.

Texture	Clay loam
Soil pH	5.95
Salinity (dS m^−1)	0.13
CaCO3 (%)	0.09
Organic matter (%)	4.14
Available phosphorus (mg kg^−1)	82.56
Available potassium (mg kg^−1)	67.15

Table 2. Protein, total oil and ash contents, and nutrient contents of hazelnut after fertilization with five different N doses.

	Nitrogen fertilization (N, kg ha^−1)
	0	100	200	400	600	P
Protein (%)	15.8 ± 0.241b	17.6 ± 0.090a	17.8 ± 0.472a	18.6 ± 0.471a	18.8 ± 0.179a	0.001**
Total oil (%)	62.1 ± 0.776a	61.7 ± 1.060ab	61.8 ± 0.137ab	62.2 ± 0.031a	59.8 ± 0.493b	0.031*
Ash (%)	2.1 ± 0.131c	2.2 ± 0.147bc	2.2 ± 0.200bc	2.4 ± 0.186ab	2.5 ± 0.144a	0.003**
Phosphorus (P, mg 100 g^−1)	292.9 ± 14.0	301.3 ± 16.4	319.0 ± 18.6	306.3 ± 21.6	283.6 ± 21.6	ns
Potassium (K, mg 100 g^−1)	580.3 ± 31.2b	657.4 ± 28.2a	644.8 ± 35.1ab	641.7 ± 34.7ab	608.6 ± 27.1ab	0.034*
Calcium (Ca, mg 100 g^−1)	176.1 ± 11.3	195.1 ± 19.4	213.8 ± 15.7	203.0 ± 19.9	190.3 ± 25.6	ns
Magnesium (Mg, mg 100 g^−1)	141.3 ± 7.46	148.0 ± 6.84	151.6 ± 12.80	150.3 ± 8.74	151.3 ± 10.3	ns
Sodium (Na, mg 100 g^−1)	2.7 ± 0.148	2.7 ± 0.280	2.9 ± 0.189	3.0 ± 0.113	3.1 ± 0.101	ns
Iron (Fe, mg 100 g^−1)	3.7 ± 0.166	3.8 ± 0.272	4.4 ± 0.697	5.4 ± 1.550	5.7 ± 1.490	ns
Copper (Cu, mg 100 g^−1)	1.7 ± 0.135ab	1.8 ± 0.123a	1.8 ± 0.108a	1.7 ± 0.148ab	1.4 ± 0.126b	0.035*
Zinc (Zn, mg 100 g^−1)	2.4 ± 0.082b	2.8 ± 0.048ab	3.0 ± 0.098a	2.9 ± 0.177ab	2.5 ± 0.260ab	0.029*
Boron (B, mg 100 g^−1)	2.5 ± 0.214b	2.7 ± 0.404ab	3.0 ± 0.318a	2.8 ± 0.248ab	2.8 ± 0.304ab	0.040*
Manganese (Mn, mg 100 g^−1)	5.2 ± 0.923b	5.6 ± 0.554b	8.1 ± 0.956ab	10.8 ± 0.712a	11.2 ± 1.100a	0.001**
Molybdenum (Mo, mg 100 g^−1)	0.051 ± 0.007a	0.048 ± 0.011a	0.039 ± 0.011ab	0.027 ± 0.008bc	0.017 ± 0.004c	0.002**

Note: All data represent the mean of three years and three replications. Each data are expressed as means ± standard error (SE) of three determinations. Data in the same column with different lowercase letters are significantly different at P < 0.05.

ns, not significant.

* Significant levels at 5%.

** Significant levels at 1%.

Table 3. Protein, total oil and ash contents, and nutrient contents of hazelnut after fertilization with five different P₂O₅ doses.

	Phosphorus fertilization (P2O5, kg ha^−1)
	0	40	80	120	160	P
Protein (%)	16.6 ± 0.489c	17.5 ± 0.241abc	17.8 ± 0.234ab	17.1 ± 0.274bc	18.5 ± 0.138a	0.002**
Total oil (%)	61.0 ± 0.192	61.0 ± 0.956	62.5 ± 1.150	62.5 ± 0.787	60.6 ± 0.930	ns
Ash (%)	2.0 ± 0.077b	2.1 ± 0.081ab	2.1 ± 0.081ab	2.4 ± 0.121a	2.4 ± 0.091a	0.014*
Phosphorus (P, mg 100 g^−1)	268.1 ± 15.2	291.9 ± 11.7	311.6 ± 22.6	317.3 ± 26.0	302.0 ± 35.0	ns
Potassium (K, mg 100 g^−1)	583.4 ± 43.1	600.0 ± 43.0	613.8 ± 40.4	616.3 ± 25.2	636.8 ± 44.8	ns
Calcium (Ca, mg 100 g^−1)	189.7 ± 14.9	180.1 ± 23.7	189.3 ± 24.3	183.6 ± 16.0	181.5 ± 18.5	ns
Magnesium (Mg, mg 100 g^−1)	143.0 ± 5.66b	144.0 ± 6.50ab	146.4 ± 8.29ab	147.8 ± 6.28ab	153.2 ± 10.40a	0.047*
Sodium (Na, mg 100 g^−1)	2.7 ± 0.189	2.6 ± 0.122	2.7 ± 0.248	2.9 ± 0.131	3.0 ± 0.084	ns
Iron (Fe, mg 100 g^−1)	4.1 ± 0.286	4.1 ± 0.517	4.5 ± 0.828	4.4 ± 0.627	4.7 ± 0.725	ns
Copper (Cu, mg 100 g^−1)	1.7 ± 0.137	1.8 ± 0.220	1.7 ± 0.155	1.5 ± 0.092	1.5 ± 0.111	ns
Zinc (Zn, mg 100 g^−1)	2.5 ± 0.115	2.6 ± 0.203	2.7 ± 0.318	3.0 ± 0.262	2.9 ± 0.424	ns
Boron (B, mg 100 g^−1)	2.8 ± 0.179	2.8 ± 0.144	2.8 ± 0.226	2.8 ± 0.270	3.0 ± 0.430	ns
Manganese (Mn, mg 100 g^−1)	5.7 ± 1.020b	7.3 ± 1.090ab	8.1 ± 0.976ab	9.1 ± 0.424a	9.8 ± 0.578a	0.014*
Molybdenum (Mo, mg 100 g^−1)	0.040 ± 0.004a	0.030 ± 0.006ab	0.023 ± 0.008ab	0.023 ± 0.004b	0.024 ± 0.003ab	0.033*

Note: All data represent the mean of three years and three replications. Each data are expressed as means ± standard error (SE) of three determinations. Data in the same column with different lowercase letters are significantly different at P < 0.05.

ns, not significant.

* Significant levels at 5%.

** Significant levels at 5%, 1%, respectively.

Table 4. Protein, total oil and ash contents, and nutrient contents of hazelnut after fertilization with five different K₂O doses.

	Potassium fertilization (kg ha^−1, K2O)
	0	200	400	600	800	P
Protein (%)	17.5 ± 0.533	17.6 ± 0.329	18.0 ± 0.326	17.6 ± 0.309	17.2 ± 0.292	ns
Total oil (%)	61.9 ± 0.334	61.9 ± 1.130	61.6 ± 0.902	61.9 ± 0.820	61.9 ± 0.962	ns
Ash (%)	2.0 ± 0.062b	2.1 ± 0.036b	2.4 ± 0.053ab	2.6 ± 0.147a	2.8 ± 0.188a	0.002**
Phosphorus (P, mg 100 g^−1)	295.7 ± 4.75	313.5 ± 26.6	329.3 ± 26.8	325.8 ± 36.4	309.2 ± 26.2	ns
Potassium (K, mg 100 g^−1)	541.4 ± 19.4	616.6 ± 46.7	662.9 ± 63.1	644.0 ± 50.2	682.6 ± 61.8	ns
Calcium (Ca, mg 100 g^−1)	176.9 ± 12.1	192.0 ± 16.3	204.2 ± 19.2	220.9 ± 46.7	205.1 ± 33.3	ns
Magnesium, (Mg, mg 100 g^−1)	144.9 ± 6.07	148.5 ± 8.00	146.3 ± 8.95	150.2 ± 9.86	149.7 ± 12.20	ns
Sodium (Na, mg 100 g^−1)	2.9 ± 0.087	2.9 ± 0.095	3.0 ± 0.046	3.2 ± 0.144	3.4 ± 0.292	ns
Iron (Fe, mg 100 g^−1)	3.7 ± 0.158	4.0 ± 0.519	3.9 ± 0.483	3.6 ± 0.355	3.6 ± 0.442	ns
Copper (Cu, mg 100 g^−1)	1.8 ± 0.072	1.9 ± 0.217	1.9 ± 0.153	1.6 ± 0.148	1.6 ± 0.077	ns
Zinc (Zn, mg 100 g^−1)	2.5 ± 0.110	2.6 ± 0.259	2.8 ± 0.300	2.7 ± 0.176	2.7 ± 0.272	ns
Boron (B, mg 100 g^−1)	2.7 ± 0.220	2.9 ± 0.284	3.1 ± 0.227	2.9 ± 0.251	2.9 ± 0.464	ns
Manganese (Mn, mg 100 g^−1)	7.0 ± 1.140	7.3 ± 0.763	7.2 ± 0.216	7.3 ± 0.704	7.8 ± 0.628	ns
Molybdenum (Mo, mg 100 g^−1)	0.043 ± 0.005a	0.033 ± 0.005ab	0.029 ± 0.012ab	0.018 ± 0.006bc	0.009 ± 0.004c	0.001**

Note: All data represent the mean of three years and replications. Each data are expressed as means ± standard error (SE) of three determinations. Data in the same column with different lowercase letters are significantly different at P < 0.05.

ns, not significant.

* Significant levels at 5%.

** Significant levels at 1%.

Table 5. Recommended dietary allowances (RDA) level of nutrients and average nutrient contents of the kernels after basic (N, P₂O₅, and K₂O) fertilizations.

	Recommended dietary allowances		Means of fertilization applications				Daily intake
Nutrient elements (mg 100 g^−1)	Unit	RDA	(N)	(P2O5)	(K2O)	Mean	(%)
Phosphorus (P)	mg	700	300.6	298.2	314.7	304.5	43.5
Potassium (K)	mg	4700	626.6	610.1	629.5	622.1	13.2
Calcium (Ca)	mg	1000	195.7	184.9	199.8	193.5	19.4
Magnesium (Mg)	mg	400	148.5	146.9	147.9	147.8	37.0
Sodium (Na)	mg	1500	2.9	2.8	3.1	2.9	0.2
Iron (Fe)	mg	8	4.6	4.4	3.8	4.3	53.8
Copper (Cu)	mg	0.9	1.7	1.6	1.8	1.7	188.9
Zinc (Zn)	mg	11	2.7	2.7	2.7	2.7	24.5
Boron (B)	mg	20	2.8	2.9	2.9	2.9	14.5
Manganese (Mn)	mg	2.3	8.2	8.0	7.3	7.8	339.1
Molybdenum (Mo)	mg	0.045	0.036	0.028	0.026	0.030	66.7

Source: http://en.wikipedia.org/wiki/Dietary_{_}Reference_{_}Intake#Vitaminsandminerals.