Plant density of lupine (Lupinus albus L.) intercropping with tef [Eragrostis tef (zucc.) trotter] in additive design in the highlands of Northwest Ethiopia

Figures & data

Figure 1. Location map of the study sites in Enerata, east Gojjam zone, northwest Ethiopia.

Figure 2. Monthly average rainfalland maximum and minimum temperatures of the study site for 15 years (2003–2017).

Table 1. Some important physicochemical properties of the experimental soils before plowing

Soil property	Soil analysis		Rating reference(s)
	Value	Rating
Particle distribution
Sand (%)	32
Silt (%)	25
Clay (%)	43
Soil texture class	Clay
pH (H2O)	5.1	Strong acidic	Hazelton and Murphy (2007)
Total N (%)	0.09	Low	Havlin et al. (1999)
Organic C (%)	1.27	Low	Walkley and Black (1934)
Avail. P (ppm)	6.85	Very low	Tekalign (1991)
CEC	20.20	Moderate	Landon (1991)

Table 2. Effect of plant density of white lupine intercropping with tef on growth and yield of tef in 2016 and 2017 main cropping season in northwest Ethiopian highlands

	Two way interaction		No. of effective tillers of tef			Panicle length of tef (cm)			Grain yield of tef (t/ha)			Straw yield of tef (t/ha)
T	IR1(cm)	IR2 (cm)	2016	2017	COY	2016	2017	COY	2016	2017	COY	2016	2017	COY
T1	20	10	2.2^d	2.3^e	2.2^d	25.5^d	24.0^c	24.8^c	0.64^d	0.63^d	0.64^d	2.33^c	2.57^c	2.42^d
T2		15	3.6^c	3.4 ^cd	3.5^c	40.3^c	41.6^b	40.8^b	0.97^c	0.92^c	0.94^c	2.75^c	2.91^c	2.80 ^cd
T3		20	4.0^c	4.2^bc	4.1^c	42.2^bc	43.3^b	42.8^b	1.01^c	1.00^bc	1.01^bc	3.33^b	3.20^bc	3.26^bc
T4	40	10	3.3^c	2.6^de	2.9^c	44.0^bc	43.6^b	43.8^b	1.08^b	1.11^b	1.10^b	3.54^b	3.73^b	3.63^b
T5		15	5.5^b	5.0^b	5.3^b	47.5^ab	43.3^b	45.4^b	1.73^a	1.69^a	1.71^a	4.42^a	4.48^a	4.38^a
T6		20	7.5^a	6.9^a	7.2^a	50.8^a	53.2^a	52.0^a	1.78^a	1.81^a	1.80^a	4.90^a	5.06^a	4.98^a
Sole			7.3^a	6.7^a	7.0^a	50.0^a	50.4^a	50.2^a	1.77^a	1.73^a	1.75^a	4.77^a	4.83^a	4.80^a
	P-value		*	*	*	*	*	*	*	*	*	*	*	*
	SE±		0.61	0.50	0.06	2.6	4.7	3.1	0.06	0.07	0.05	0.22	0.30	0.23
	CV%		12.3	17.2	6.8	7.6	13.2	8.1	6.8	7.7	5.8	7.5	10.1	7.8

Means within a column followed by the same letter(s) are not significantly different: * = significant at P < 0.05; T = Treatment; TND = total nich differntatation; IR1 = inter-row spacing of lupine; IR2 = intra-row spacing of lupine; SE ± = standard error; CV = coefficient of variation,; COY = combined over years

Table 3. Effect of plant density of white lupine intercropping with tef on growth and yield of lupine in 2016 and 2017 main cropping season in northwest Ethiopian highlands

	Two way interaction		No. of branches per lupine			No. of pods per lupine plant			Grain yield of lupine (t/ha)
T	IR1 (cm)	IR2 (cm)	2016	2017	COY	2016	2017	COY	2016	2017	COY
T1	20	10	2.6 ^d	1.4^e	2.0^d	31.3^b	30.6^b	31.0^c	1.37 ^cd	1.42^c	1.40 ^cd
T2		15	4.6^c	4.0^d	4.3^c	32.0^b	34.0^b	33.0^c	1.50^b	1.55^b	1.53^bc
T3		20	4.6^c	4.3 ^cd	4.5^c	32.8^b	33.8^b	33.3^c	1.40 ^cd	1.50^c	1.45^c
T4	40	10	4.7^c	5.0^bc	4.8^bc	33.0^b	32.6^b	32.8^c	1.60^b	1.66^b	1.63^b
T5		15	5.0^bc	5.3^bc	5.2^bc	40.7^a	42.3^a	41.5^b	1.43 ^cd	1.37 ^cd	1.40 ^cd
T6		20	7.5^a	7.3^a	7.4^a	45.6^a	47.0^a	46.3^a	1.11^e	1.01^d	1.06^e
Sole			7.6^a	7.8^a	7.7^a	46.3^a	47.7^a	47.0^a	2.78^a	2.68^a	2.74^a
	P-value		*	*	*	*	*	*	*	*	*
	SE±		0.30	0.32	0.26	0.43	2.3	2.1	1.3	0.08	0.07
	CV%		8.3	7.8	4.8	11.7	13.3	10.6	9.5	6.8	6.5

Means within a column followed by the same letter(s) are not significantly different: * = significant at P < 0.05; T = Treatment; IR1 = inter-row spacing of lupine; IR2 = intra-row spacing of lupine; COY = combined over years; SE ± = standard error; CV = coefficient of variation

Table 6. Production efficiency of tef-lupine intercropping in 2016 and 2017 main cropping season (combined over years) in northwest Ethiopian highlands

Two way interaction			Partial LER for tef	Partial LER for lupine	Total LER	TEY (t ha^−1)	ATER	MAI
T	IR1 (cm)	IR2 (cm)
T1	20	10	0.36^d	0.51^c	0.87^e	1.34^d	0.71^d	−189.0^d
T2		15	0.54^c	0.55^ab	1.10^d	1.71^c	0.89^c	118.1^c
T3		20	0.57^bc	0.54^ab	1.11^d	1.74^c	0.88^c	128.8^c
T4	40	10	0.63^b	0.60^a	1.22^c	1.91^b	1.01^b	240.6^b
T5		15	0.95^a	0.47^c	1.42^a	2.32^a	1.09^a	396.2^a
T6		20	0.97^a	0.38^d	1.35^a	2.23^a	1.03^b	348.9^a
	SE±		0.04	0.03	0.05	0.04	0.03	771

LER = land equivalent ratio; TEY = tef equivalent yield; ATER = area time equivalent ratio; MAI = monetary advantage index; T = treatment; IR1 = inter-row spacing of lupine; IR2 = intra-row spacing of lupine; SE ± = standard error.

Table 4. Competitive ratio and aggressivity of tef and lupine in tef-lupinein intercropping system in 2016 and 2017 main cropping season in northwest Ethiopian highlands

Twoway interaction			2016		2017		COY		2016		2017		COY
T	IR1(cm)	IR2 (cm)	CRT	CRL	CRT	CRL	CRT	CRL	AT	AL	AT	AL		AT	AL
T1	20	10	0.70^bc	1.44^b	0.72^c	1.40^b	0.72^c	1.41^b	−0.14^b	0.14^b	−0.28^d	0.28^a		−0.15^b	0.15^b
T2		15	0.99^b	1.01 ^cd	0.94^b	1.06^c	0.97^b	1.03^c	−0.03^ab	0.03^bc	0.13^b	−0.13^bc		−0.01^b	0.01^b
T3		20	1.08^a	0.92 ^cd	1.07^b	0.94^c	1.08^ab	0.92^c	0.03^ab	−0.03^bc	−0.18^b	+0.18^c		+0.04^b	−0.04^bc
T4	40	10	0.49^c	1.90^a	0.51^d	1.94^a	0.53^d	1.92^a	−0.87^d	0.87^a	−0.02^c	0.02^b		−0.85^c	0.85^a
T5		15	1.03^ab	0.98^c	1.02^b	0.99^c	1.02^b	0.98^c	0.17^a	−0.17^c	0.15^b	−0.15^bc		0.02^b	−0.02^c
T6		20	1.17^a	0.86^d	1.36^a	0.74^d	1.28^a	0.80^c	0.18^a	−0.18^d	0.48^a	−0.48^d		0.30^a	−0.30^d
	SE±		0.10	0.17	0.09	0.11	0.09	0.11	0.10	0.10	0.11	0.11		0.08	0.08

CR = competitive ratio of tef and lupine in intercropping; A = aggressivityof tef and lupine in intercropping; T = Treatment; IR1 = inter-row spacing of lupine; IR2 = intra-row spacing of lupine; COY = combined over years; SE ± = standard error.

Table 5. Actual yield loss of tef and lupine in tef-lupine intercropping system in 2016 and 2017 main cropping season in northwest Ethiopian highlands

Two way interaction			2016			2017			COY
T	IR1 (cm)	IR2 (cm)	AYLt	AYLl	AYLtt	AYLt	AYLl	AYLtt	AYLt	AYLl	AYLtt
T1	20	10	−0.60^d	−0.40^c	−1.00^d	−0.52^d	−0.47^d	−0.99^e	−0.57^d	−0.40^d	−0.97^c
T2		15	−0.46^c	−0.49^d	−0.92^d	−0.45^c	−0.42^d	−0.87^de	−0.45^c	−0.45^d	−0.89^c
T3		20	−0.43^c	−0.44^c	−0.87^c	−0.41^c	−0.45^d	−0.79^d	−0.42^c	−0.46^d	−0.89^c
T4	40	10	−0.08^b	0. 80^a	0.70^ab	−0.01^c	0. 81^a	0.80^ab	−0.04^b	0.80^a	0.75^ab
T5		15	0.40^a	0.43^b	0.82^a	0.50^a	0.42^b	0.92^a	0.45^a	0.42^b	0.87^a
T6		20	0.42^a	0.21^c	0.63^b	0.53^a	0.14^c	0.67^c	0.47^a	0.17^c	0.64^b
	SE ±		0.05	0.08	0.09	0.05	0.08	0.10	0.04	0.05	0.10

AYLt = actual yield loss of tef; AYLl = actual yield loss of lupine; AYLtt = actual yield loss of total; T = treatment; IR1 = inter-row spacing of lupine = IR2, intra-row spacing of lupine;COY = combined over years; SE ± = standard error.

Table 7. Economic profitability of tef-lupine intercropping as influenced plant density of white lupine intercropping with tef in 2016 and 2017 main cropping season (combined over years)

Treatment	IR1 (cm)	IR2 (cm)	Adj. tef GY(t/ ha)	Adj. tef SY(t/ ha)	Adj. lupine GY(t/ ha)	GB (USD/ha)	VB (USD/ha)	NB (USD/ha)	MRR (%)
	Sole tef		1.58	4.32	0	2066.7	36.1	2030.5
T6		20	1.53	4.3	0.95	2513.7	116.5	2397.2	457
T5		15	1.51	3.95	1.26	2607.8	128.5	2479.3	682
T4	40	10	0.99	3.3	1.47	2145.8	152.6	1993.2	D
T3		20	0.91	2.93	1.31	1936.3	168.7	1767.7	D
T2		15	0.86	2.53	1.37	1865.3	200.8	1664.5	D
T1	20	10	0.58	2.18	1.26	1500.0	273.1	1226.9	D

IR1 = Inter-row spacing of lupine; IR2 = Intra-row spacing of lupine; GY = Grain yield, SY = Straw yield price; GB = Gross field benefit; VB = Variable cost; NB = Net benefit; MRR = marginal rate of return; (USD kg⁻¹) of tef grain yield; straw yield and luine grain yield were 0.95, 0.55, and 0.15, respectively. Labour cost man day⁻¹ was 3.30 USD.

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