Response of Bread Wheat (Triticum aestivum L.) to Potassium (K) and Blended NPS Fertilizer Rates in the Nitisols of Southern Ethiopia

Table 11

Partial budget analysis for NPS fertilizer rate and K fertilizer application.

NPS and KCl rate (kg ha^−1)	GY (t·ha^−1)	ADY (t·ha^−1)	Net benefits (birr·ha^−1)	Total variable cost (birr)	Marginal net benefit (birr)	Marginal variable cost (birr)	MRR (%)
0, 0	0.43	0.392	3920	—	—	—	—
0, 25	0.48	0.437	4370	304.28	450	304.28	147.9
0, 50	1.19	1.067	10670	608.57	6300	304.28	2070.5
0, 75	1.12	1.0019	10019	912.8	−651	304.28	−213.9
50, 0	1.01	0.9119	9119	776	—	—	—
50, 25	1.23	1.1097	11097	1080.28	1978	304.28	650
50, 50	1.88	1.689	16890	1384.57	5793	304.28	1903.8
50, 75	1.99	1.791	17910	1688.85	1020	304.28	335.2
100, 0	1.99	1.791	17910	1552	—	—	—
100, 25	2.23	2.004	20040	1856.28	2130	304.28	700
100, 50	2.98	2.684	26840	2160.57	6800	304.28	2234.8
100, 75	2.87	2.583	25830	2464.85	−1010	304.28	−331.9
150, 0	2.29	2.0603	20603	2328	—	—	—
150, 25	2.89	2.603	26030	2632.28	5427	304.28	1783.5
150, 50	4.33	3.897	38970	2932.28	12940	304.28	4252.6
150, 75	3.44	3.09	30900	3240.85	−8000	304.28	−2652.1
200, 0	2.49	2.639	22430	3104	—		—
200, 25	2.72	2.448	24480	3408.28	2050	304.28	673.7
200, 50	3.25	2.925	29250	3712.57	4770	304.28	1567.6
200, 75	2.86	2.574	25740	4016.85	−3510	304.28	−1153.5

GY: grain yield; ADY: adjusted grain yield; MRR: marginal rate of return.