Effects of Brewery waste sludge on potato (Solanum tuberosum L.) productivity and soil fertility

Figures & data

Table 1. Comparison of physicochemical characteristics of experimental soil before and brewery waste sludge (BWS) used

Parameters	Before application	Brewery waste sludge (BWS)	Difference in percent
pH	8.49	8.67	2.08
Total N, %	0.08	1.33	93.98
Organic Carbon, %	1.18	3.50	66.29
Available P, mg kg^−1	7.51	39.75	81.11
Zn (mg kg^−1 soil)	6.00	28.50	78.95
Fe (mg kg^−1 soil)	24.71	20.50	−17.04
Cd (mg kg^−1 soil)	0.73	1.27	42.52
Ni (mg kg^−1 soil)	19.33	31.33	38.30
Mn (mg kg^−1 soil)	3.63	0.83	−77.13
Co (mg kg^−1 soil)	32.00	33.00	3.03
Cu (mg kg^−1 soil)	3.50	20.00	82.5
Se (mg kg^−1 soil)	12.87	12.56	2.41
Mo (mg kg^−1 soil)	1.00	0.45	−55
Cr (mg kg^−1 soil)	1.72	0.47	−72.67

Table 2. Mean growth, yield and yield components of potato

Sludge levels (t ha^−1)	Survival percentage of plant	Plant height (cm)	Total biomass g plant^−1	Small size tuber t ha^−1	Large size tuber t ha^−1	Medium size tuber t ha^−1	Marketable tuber t ha^−1	Unmarketable tuber t ha^−1	Total tuber yield (t ha^−1)
2	84.38	49.56^ab	432.10^b,c	2.24	5.49^a,b	4.46^b,c	10.64^b,c	1.52^g	12.16^bc
4	86.81	45.06^a,b	555.60^b,c	1.42	6.09^a,b	4.80^b,c	10.74^b,c	1.57^f	12.31^bc
6	87.15	51.59^a,b	617.30^b	1.08	9.88^a,b	5.37^b,c	14.05^b	2.28^d	16.33^b
8	87.84	53.99^a,b	401.20^b,c	1.33	8.39^a,b	7.27^b	14.55^a,b	2.44^c	16.99^a,b
10	84.38	54.35^a	864.20^a,b	2.16	1.01^a,b	1.13^a	21.03^a	2.50^b	23.53^a
12	80.90	53.55^a,b	925.90^a	1.61	1.12^a	8.06^a,b	17.72^a,b	3.12^a	20.84^a,b
NP	88.19	46.76^a,b	339.50^b,c	1.099	4.40^a,b	2.46^c	6.05^b,c	1.88^e	7.93^b,c
0	84.38	39.19^b	246.90^c	.64	2.44^b	3.25^bc	5.38^c	8.70^h	14.08^c
LSD (0.05)	4.92	8.21	259.40	1.82	4.54	4.49	7.78	2.09	7.11
CV (%)	5.40	11.34	32.19	85.75	42.62	52.00	42.26	57.63	33.91

CV = coefficient of variation, LSD = least significant difference, t ha⁻¹ = tons per hectare, and means in columns of the same parameter followed by the same letter(s) are not significantly different at 5% level of significance.

Table 3. Physicochemical characteristics of the soil before and after application of brewery waste sludge (BWS)

Sludge levels (t ha^−1)	Mean concentration of heavy metals in mg kg^−1 soil
	Zn	Fe	Cd	Ni	Mn	Co	Cu	Se	Mo	Cr
Soil boundary Values (EU)	100	–	3	50	–	20	80	2.0	–	150
Sludge boundary Values (EU)	2500	–	30	300	–	–	1000	–	–	1000
Before application	6	24.71	0.73	19.33	3.63	32	3.5	12.87	1	1.72
2*	17.00	24.71	0.93	31.33	3.61	26.00	6.00	13.37	1.55	0.19
Change (%)	64.71	0.00	21.51	38.30	−0.55	−18.75	41.67	3.74	35.48	−88.95
4*	8.00	24.71	1.20	34.67	3.50	27.00	5.00	12.94	0.64	0.50
Change (%)	25	0.00	39.17	44.25	−3.58	−15.63	30	0.54	−36	70.93
6*	12.50	24.45	0.78	24.33	3.15	38.00	0.50	12.50	1.18	0.66
Change (%)	52	−1.05	6.4	20.55	−13.22	15.79	−85.71	−2.87	15.25	−61.63
8*	15.00	24.45	0.05	11.67	3.36	27.00	4.00	12.87	1.27	0.72
Change (%)	60	−1.05	−93.15	−39.63	−7.44	−15.63	12.5	0.00	21.26	−58.14
10*	11.00	25.24	1.21	22.67	3.25	18.00	4.00	11.62	0.64	0.38
Change (%)	45.45	2.10	39.67	14.73	−10.47	−43.75	12.5	−9.71	36	−77.91
12*	6.50	24.71	1.27	6.00	3.11	17.00	1.50	11.37	0.55	0.81
Change (%)	7.69	0.00	54	−68.96	−14.33	−46.88	−57.14	−11.66	−45	−52.91
NP-fertilizer*	2.50	24.76	1.29	25.33	3.64	24.00	5.50	12.94	0.36	1.34
Change (%)	−58.33	0.20	43.41	23.69	0.27	−25	36.36	0.54	−64	−22.09
0**	11.50	24.47	1.23	19.67	3.68	20.00	4.50	12.75	0.73	1.69
Change (%)	47.83	−0.97	40.65	1.73	1.36	−37.5	22.22	−0.93	−27	1.74

EU = European Union standard, 2001; *after application of brewery waste sludge; **without application of brewery waste sludge, and Change (%) = the change in percentage for heavy metal accumulation in the soil before and after application of brewery waste sludge (BWS).