Abstract
Background and objective
Intercropping is one of the sustainable intensification methods which reduces the demand for increased land resources. However, growing of two or more crops as an intercrop is not business as usual but it needs extensive knowledge about the nature of component crops to grow in harmony. Hence selection and evaluation of compatible legume species for intercropping with finger millet in the study area is necessary.
Materials and methods
A field experiment was conducted at two major finger millet producing areas of northwestern Ethiopia. Four legumes crops such as (sweet lupine, cowpea, haricot bean, and soybean) intercropped with finger millet.
Results
The analysis of variance showed that intercropping of finger millet with different legumes had yield advantage in both districts as compared to component crops. Land equivalent ratio was more than unity for all treatments in both districts except for finger millet intercropped with soybean at South Achefer district. At Guangua finger millet + cowpea and finger millet + soybean showed 27% and 12% yield advantage, respectively and also finger millet + cowpea preferred first by farmers for its high grain yield, soil fertility improvement and its suitability for animal feed. At South Achefer finger millet + sweet lupine and finger millet + cowpea showed 38% and 35% yield advantage respectively and also finger millet + sweet lupine preferred first by farmers for its high grain yield to make stew as a protein source, soil fertility improvement and its suitability for human and animal feed.
Conclusion
Therefore intercropping, finger millet + cowpea and finger millet + soybean at Guangua and finger millet + sweet lupine and finger millet + cowpea at South Achefer preferred by farmers and also had yield advantage as compared to component crops. Hence finger millet + cowpea and finger millet + soybean recommended for Guangua and similar agro-ecologies and finger millet + sweet lupine and finger millet + cowpea for South Achefer and similar agro-ecologies as 1st, 2nd option respectively.
Keywords: Farmers' preference, Finger millet, Legumes, Land equivalent ratio, Multiple cropping
Farmers’ preference; Finger millet; Legumes; Land equivalent ratio; Multiple cropping.
1. Introduction
Intercropping is an eco-functional intensification practice, widely used to increase crop productivity as well as, land utilization ratio [1]. It also minimizes crop failure, reduce soil erosion, improve the soil fertility, increase crop yield and provide higher returns [2]. It is the most efficient land-use system adopted in tropical regions, where farmers have very limited access to agricultural inputs [1]. Intercropping have an advantages compared to monocropping this is because the component crops can use the growth resources complementary in either space or time [3,4]. Most of the farmer in Sub-Saharan Africa intercropped cereals with legumes to reduce the risk of monoculture [2,5]. Among the cereal-legume intercropping systems, the combination of finger millet with pigeon pea (Cajanus cajan), soybean (Glycine max), haricot bean (Phaseolus vulgaris) and groundnut (Arachis hypogaea) are the common farming practices in Sub-Saharan Africa [6].
Finger millet is the 5th top 10 crop lists frequent adopted for intercropping [7]. Because of its ability to tolerate dry season, insects, disease and other factors, most of the farmer widely grow finger millet by low inputs [8]. Farmers mainly grow finger millet as a sole crop and traditionally they grow it in combination with pulse crops to provide a range of different foods for their dish [9]. Grain legumes such as haricot bean and sweet lupine are multipurpose crops and produced in mid-altitude of northwestern Ethiopia [10,11]. However, we had conducted a survey on the cropping system of finger millet in major growing areas of the Amhara region particularly in West Gojjam and Awi zones. Most of the farmers in these areas produced finger millet as a sole crop or in rotation with maize and only a few farmers produced finger millet in rotation with lupine and soybean. Besides, these farmers do not apply the recommended fertilizer (41 kg ha−1 N and 46 kg ha−1 P2O5) rate for growing finger millet. Instead apply a very small amount of inorganic fertilizers, because of unaffordability to the majorities of farmers. Therefore, the search for low-cost and environmentally friendly alternatives to improve soil fertility and the yield of finger millet is imperative that is consistent with the current focus of global agriculture [12].
There are few practices on lupine intercropping and rotation with cereals due to its adaptability, stability, and feasibility of production under low soil fertility status. Due to lack of awareness for its adaptability, the system is not expanding to major finger millet production areas of the region. However, the potential of growing legumes in association with major staple food crops like finger millet could be substantially enhanced through intercropping. The choice of compactable crops depends on plant growth habit, land, light, water, and fertilizer utilization [13]. To bring a new finger millet-based cropping system, it is vital to see the integration of potential legume crops for intercropping with finger millet in major growing areas of the region. Therefore, aim of this study were to (i) identify and evaluate the potential and compatible legume species for intercropping with finger millet, (ii) assess farmer's finger millet and legume technologies preference and, (iii) enhance demand-driven technology dissemination.
2. Materials and methods
2.1. Description of the study areas
The experiment was carried out at Guangua and South Achefer districts of Western Amhara Region, Ethiopia. South Achefer is located at 11°5′ N and 37°52′ E in the Blue Nile Basin with an altitude that ranges from 1500-2600 m above sea level. The district has an average rainfall ranging from 1365 to 1623 mm with an average minimum and maximum temperature of 11.8 °C and 28.8 °C, respectively. Nitosol is the dominant soil type and the most commonly produced annual crops in the district are maize, finger millet, tef, bread wheat, barley, faba bean, grass pea, chickpea, field pea and Niger seed (noug). Guangua district is located at 10°57′- 10°95′ N and 36°30′- 36°50′ E with an elevation range from 800-2300 masl. The district has a total area of about 2304.21 square kilometers with an annual rainfall that ranges from 1300 to 1800mm. The average minimum and maximum temperatures are 22 °C and 31 °C, respectively. The common annual crops produced in the district are maize, finger millet, sorghum, Niger seed (noug), rapeseed, and bread wheat.
2.2. Treatments, experimental design, and procedures
The experiment consisted of four legumes (haricot bean (Awash 2), soybean (Ethioyigozaliviia), cowpea (IT99K-1122), and sweet lupine (Sanabor)) and intercropped with finger millet (Necho variety) in each study area. Sole legumes and sole finger millet were part of the treatments. The treatments were arranged in Randomized Complete Block Design (RCBD) with three replications. The blocks were separated by a 1.5 m wide-open space whereas the plots within a block were 0.6 m apart from each other. Legumes were intercropped equidistance between the rows of finger millet. Each plot had a gross plot size of 12 m2 with 3 m in length and 4 m in width. The recommended rate of 46 kg ha−1 P2O5 was applied at planting. Split application of urea at a rate of 50 kg ha−1 was applied 1/3rd at planting and the remaining 2/3rd at tillering stage. Finger millet was sowed by hand drilling in rows spaced 40 cm apart on June 15 in 2017/2018 at seed rate of 10 kg ha−1 and the rate for each legume determined based on their spacing between plants. But row spacing of legumes was determined by the row spacing of finger millet. Spacing between plants for legume crops was 10 cm planting was done based on the farmers planting time in each site. Participatory technology evaluation was conducted for selecting the finger millet-legume intercrop system by further disaggregating according to gender.
Field design and treatment arrangements of finger millet intercropped with legumes
2.3. Research extension approach
Participatory technology development approach was followed in implementing and evaluating the research activity. Farmers-Research-Extension-Groups (FREGs) approach was established to evaluate and select the best finger millet-legume intercropping systems according to their criteria. FREG is a small group of farmers (usually 15–35 members) and extension agents who have common problems and are interested to work in groups in collaboration with research, extension and with other non-public organizations in the process of technology generation, verification, demonstration, and improvement [14,15]. Based on this, FREG groups were formed in each kebele comprising 20–30 member farmers and participated throughout the planning to the implementation process of the on-farm evaluation activity. Moreover, for easy communication and facilitation, farmers were able to organize themselves and elected their chairperson and secretary after a multidisciplinary team of researchers held discussions with the targeted farming communities and extension workers on the objectives and implementation of the already planned on-farm evaluation activity.
2.4. Technology evaluation and demonstration methods
Evaluations of the technologies were done by FREGs member farmers with the help and facilitation of researchers and extension agents. Participatory variety evaluations were carried out at the maturity stage of the crop and farmers were able to identify evaluation criteria based on their own experiences related to finger millet, legumes, and intercropping. The criteria were ranked and prioritized in order of their importance by using the pairwise ranking method. Each treatment under evaluation was then evaluated by criterion by direct scoring methods (1 = the best and >9 less important). Scores given to each treatment with each criterion of group results were added together and then ranked in ascending order in each district (the lowest sum gives the best score). The sum of preference value (score x weight) of each treatment across each criterion was used to determine the final acceptability rank among the varieties in each location.
2.5. Types and methods of data collection
Qualitative and quantitative yield-related data such as plant height, tiller number, and finger length along with social data were collected. Yield data and related-parameters were collected after harvest and social data (farmers' and expert's opinions/feedbacks) were collected during monitoring and evaluation (M and E), technology evaluation, and field day events.
2.6. Data analysis
Farmer's preference was analyzed qualitatively through narration and description and yield data were subjected to analysis of variance (ANOVA) using GLM procedures SAS [16]. Social data (farmers' and expert's opinions/feedbacks) was simply qualitatively described and classified by themes and contents. A combined analysis over the site was made considering the site as a random variable. LSD was made at 5% of probability levels when the analysis of variance indicates the presence of significant differences [17].
Land equivalent ratio (LER) was calculated using the formula outlined by [18].
| Equation (1) |
where Yi and Ys are yields of component crops in intercrop and sole cropping, respectively, and n is the number of the crops involved.
3. Results
A total of 95 (9 females) individuals comprising 59 (4 females) farmers and 36 agricultural experts (5 females) participated in the training (Table 1). During the training, presentations, leaflets, posters, and audio-visual materials prepared in the local Amharic language were used as training materials.
Table 1.
Training delivered and number of participants at Guangua and South Achefer districts.
| Title of the training | District | Kebele | Training participants |
|||
|---|---|---|---|---|---|---|
| Farmers |
Experts |
|||||
| Male | Female | Male | Female | |||
| Finger millet production, agronomic practices, seed production, and crop protection | Guangua | Yimali and Tirubrhan | 41 | 2 | 17 | 3 |
| South Achefer | Abichikili and Ahuri | 18 | 2 | 14 | 2 | |
|
Total |
59 |
4 |
31 |
5 |
||
| 59 | 36 | |||||
| 95 | ||||||
High yield, suitable for home consumption, suitable for animal feed, and soil restoration (the ability of crops in soil fertility improvement by fixing atmospheric Nitrogen) were their main selection criteria for finger millet and legume intercropping production at Guangua district (Table 2). Farmers gave great emphasis towards high yielding ability and suitability for home consumption followed by abundance and suitability for animal feed. Farmers also gave due importance for organic, accessible, and cheap sources of fertilizers to keep the fertility of their land since inorganic ones are being costly and legumes are the best sources of this kind.
Table 2.
Pairwise ranking of farmer's selection criteria at Guangua district.
| Farmer's Selection criteria | HY | AF | SR | HC | Rank |
|---|---|---|---|---|---|
| Higher yield (HY) | HY | HY | HY | 1 | |
| Animal feed (AF) | AF | HC | 3 | ||
| Soil restoration (SR) | HC | 4 | |||
| Home consumption (HC) | 2 |
HY = Higher yield; AF = Animal feed; SR = Soil restoration; and HC = Home consumption.
Based on farmers selection criteria at Guangua the lowest rank (1st) was recorded from intercropping of finger millet with cowpea, that means it was the best preferred cropping system by while the highest rank (9th) was obtained from sole sweet lupine means less preferred by farmers in the area (Table 3).
Table 3.
Sum of the score and final rank of varieties with farmer's selection criteria at Guangua district (the lowest score is the best).
| No | Treatments | Farmer's Selection criteria |
Total score | Rank | |||
|---|---|---|---|---|---|---|---|
| HY (1) | AF (3) | SR (4) | HC (2) | ||||
| 1 | Sole finger millet | 38 | 42 | 98 | 48 | 226 | 5th |
| 2 | Sole soybean | 42 | 168 | 38 | 162 | 410 | 6th |
| 3 | Sole haricot bean | 78 | 152 | 28 | 158 | 416 | 8th |
| 4 | Sole cowpea | 24 | 19 | 28 | 342 | 413 | 7th |
| 5 | Sole sweet lupine | 278 | 28 | 22 | 90 | 418 | 9th |
| 6 | Finger millet + soybean | 12 | 36 | 18 | 42 | 108 | 2nd |
| 7 | Finger millet + haricot bean | 22 | 52 | 22 | 32 | 128 | 4th |
| 8 | Finger millet + cowpea | 11 | 16 | 14 | 34 | 75 | 1st |
| 9 | Finger millet + sweet lupine | 32 | 38 | 18 | 24 | 112 | 3rd |
HY = Higher yield, AF = Animal feed, SR = Soil restoration, and HC = Home consumption.
The main farmers own selection criteria in South Achefer district were similar with that of Guangua district so that high yield, suitable for home consumption, suitable for animal feed and soil restoration (soil fertility improvement) were their main selection criteria for finger millet and legume intercropping production (Table 4). Farmers and agricultural experts were invited to evaluate the treatments under study.
Table 4.
Pairwise ranking of farmer's selection criteria at South Achefer district.
| Farmer's Selection criteria | HY | AF | SR | HC | Rank |
|---|---|---|---|---|---|
| Higher yield (HY) | HY | HY | HY | 1 | |
| Animal feed (AF) | AF | HC | 3 | ||
| Soil restoration (SR) | HC | 4 | |||
| Home consumption (HC) | 2 |
HY = Higher yield, AF = Animal feed, SR = Soil restoration, and HC = Home consumption.
At South Achefer based on the final ranking the highest ranking was observed from sole cowpea and followed by sole soybean and sole haricot bean. The lowest ranking was observed from finger millet intercropped with sweet lupine and followed by finger millet intercropped with cowpea and haricot bean and also the best preferred intercropping system in the area (Table 5). In general, sole crops were less preferred by farmers as compared to intercropped and less preferred by farmers in the area.
Table 5.
Sum of the score and final rank of varieties with farmer's selection criteria at South Achefer district (the lowest score is the best).
| No | Treatments | Farmer's Selection criteria |
Total score | Rank | |||
|---|---|---|---|---|---|---|---|
| HY (1) | AF (3) | SR (4) | HC (2) | ||||
| 1 | Sole finger millet (FM) | 42 | 40 | 88 | 36 | 206 | 5th |
| 2 | Sole soybean (SB) | 88 | 164 | 28 | 161 | 441 | 8th |
| 3 | Sole haricot bean (HB) | 80 | 150 | 28 | 158 | 416 | 7th |
| 4 | Sole cowpea (CP) | 48 | 22 | 24 | 358 | 452 | 9th |
| 5 | Sole sweet lupine (SL) | 56 | 32 | 28 | 92 | 208 | 6th |
| 6 | Finger millet + soybean | 24 | 38 | 17 | 48 | 127 | 4th |
| 7 | Finger millet + haricot bean | 21 | 51 | 18 | 32 | 122 | 3rd |
| 8 | Finger millet + cowpea | 11 | 17 | 15 | 38 | 81 | 2nd |
| 9 | Finger millet + sweet lupine | 11 | 18 | 17 | 25 | 71 | 1st |
HY = Higher yield, AF = Animal feed, SR = Soil restoration, and HC = Home consumption.
3.1. Mean grain yield and yield component of finger millet
The combined analysis of variance showed that grain yield, plant height, tiller number, and finger length was significantly (P < 0.05) affected by intercropping of different legumes species. However, at South Achefer intercropping of finger millet with legumes significantly affected plant height and tiller number but not finger length and grain yield (Table 6). At Guangua the maximum grain yield (893.52 kg ha−1) was obtained from FM + SL, but FM + CP gave the lowest grain yield (576.39 kg ha−1) as compared to other treatments. Intercropping SL with FM maximizes plant height of FM whereas FM intercropped with HB reduced plant height of FM probably due to low competition for the available light. Tiller number ranged from (40.63–30.66) the maximum and minimum tiller numbers were recorded from sole FM and FM + CP respectively. The maximum finger length (13.87 cm) was recorded from sole finger millet due to low competition for space, nutrients, and water. While, the minimum finger length (11.05 cm) was recorded from finger millet intercropped with cowpea due to high competition for the available resource (Table 6). At South Achefer, grain yield of finger millet was not significantly affected by intercropping finger millet with different legumes. Plant height ranged from (89.27 at FM + SL to 71.0 at FM + HB). The maximum tiller number (51.04) was recorded from sole finger millet but the minimum tiller number was recorded from finger millet intercropped with sweat lupine.
Table 6.
Combined mean grain yield and yield components of finger millet at Guangua and South Achefer districts.
| Treatments | Guangua |
South Achefer |
||||||
|---|---|---|---|---|---|---|---|---|
| Ph (cm) | T m−2 | Fl (cm) | Gy kg ha−1 | Ph (cm) | T m−2 | Fl (cm) | Gy kg ha−1 | |
| Sole FM | 80.61abc | 40.63a | 13.87a | 992.46a | 75.59b | 51.04a | 12.47 | 1055.7 |
| FM + SB | 84.04ab | 33.97b | 13.21ab | 592.11c | 76.62b | 46.04ab | 11.87 | 764.86 |
| FM + HB | 75.60c | 33.16b | 13.15ab | 809.20b | 71.00b | 42.82b | 12.13 | 926.02 |
| FM + CP | 78.51bc | 30.66b | 11.65c | 576.39c | 71.37b | 46.70ab | 12.04 | 888.62 |
| FM + SL | 85.68a | 34.59ab | 12.57b | 893.52ab | 89.27a | 40.73c | 12.24 | 843.86 |
| LSD (0.05) | 6.24 | 5.98 | 0.81 | 163.63 | 10.8 | 5.9 | ns | ns |
| CV (%) | 7.99 | 17.93 | 6.55 | 21.92 | 14.58 | 13.41 | 8.7 | 22.0 |
Means with the same letter within a column are statistically non-significant, FM = Finger millet, SB = Soybean, HB = Haricot bean, CP = Cowpea, SL = Sweet lupine, Fl = finger length, Ph = plant height, T = tiller number per m2 and Gy = grain yield kilogram per hectare.
3.2. Mean grain yield of legumes
At Guangua sole cowpea and soybean were well performed as compared to intercropped legumes with finger millet. The maximum grain yield was recorded from sole cowpea (1305.37), sole soybean also gave optimum yield, however, SL + FM and HB + FM gave minimum grain yield (Table 7). At South Achefer, sole sweet lupine and sole cowpea adapted well. Among intercropped legumes, the maximum grain yield (1925.25 kg ha−1) was recorded from sole sweet lupine, sole cowpea also gave higher grain yield as compared with intercropped legumes, but intercropping finger millet with soybean gave minimum grain yield.
Table 7.
Combined mean grain yield of legumes across sites in Gungua and South Achefer district.
| Gungua |
South Achefer |
|||
|---|---|---|---|---|
| Grain yield (kg ha−1) | ||||
| Sole crop | Intercrop | Sole crop | Intercrop | |
| Soybean | 1107.81 | 577.84 | 366.88 | 61.78 |
| Haricot bean | 638.21 | 353.44 | 116.40 | 106.56 |
| Cowpea | 1305.37 | 905.67 | 666.98 | 362.07 |
| Sweet lupine | 677.60 | 156.03 | 1925.25 | 1054.17 |
3.3. Land equivalent ration
Land equivalent ratio (LER) is a measure of the efficiency of land use in an intercropping experiment. It indicates the efficiency of intercropping for using the resources of the environment. Compared with mono-cropping [19]. Land equivalent ratio (LER) was calculated using the formula outlined by [18] and when LER = one, component crops are complementary. However, LER value of 1.0 indicating no difference in yield between the intercrop and the collections of monocultures [20]. When the LER is greater than one, the intercropping favors the growth and yield of the species. On other hand, a total of LER of higher than 1.0 indicates the presence of positive inter-specific interference that exists in the mixture is not as intensive as the inter-specific interference that exists in the monoculture [21]. Based on the formula mentioned in Eq. (1) the LER was calculated and in all locations, LER were more than unity and more advantageous as compared to sole finger millet except finger millet intercropped with soybean at South Achefer (Table 8). At Guangua finger millet intercropped with haricot bean, cowpea, sweet lupine, and soybean gave (1.37, 1.27, 1.13 and 1.12) LER, respectively, which means intercropping of finger millet with all legumes were more advantage compared to sole finger millet but, based on farmer's, preference finger millet intercropped with cowpea, soybean, and sweet lupine ranked 1st, 2nd, and 3rd respectively. At South Achefer finger millet intercropped with haricot bean, cowpea and sweet lupine gave (1.79, 1.38, and 1.35) LER, respectively, and based on farmer's preference finger millet intercropped with sweet lupine, cowpea, and haricot bean ranked 1st, 2nd, and 3rd respectively.
Table 8.
LER of Finger millet-legume intercropping at Guangua and South Achefer district.
| Treatments | Guangua |
South Achefer |
|---|---|---|
| LER | ||
| Finger millet + Soybean | 1.12 | 0.89 |
| Finger millet + Haricot bean | 1.37 | 1.79 |
| Finger millet + Cowpea | 1.27 | 1.38 |
| Finger millet + sweet lupine | 1.13 | 1.35 |
LER = Land equivalent ratio.
4. Discussion
Pairwise ranking and final preference values analysis results at Guangua showed that FM + CP was highly preferred for its high grain yield, soil fertility improvement (restoration) and its suitability for animal feed (cowpea green biomass and its grain is best animal feed for cattle and sheep/goat since livestock feed is a serious problem in those areas) while it was less preferred due to its less suitability (prefer-ability) of cowpea grain for home consumption (Table 2). FM + SB was secondly preferred due to its high grain yield, a good adaptation of soybean, and its goodness for soil fertility restoration while it is less preferred due to its less suitability of soybean grain for household food consumption. FM + HB was preferred by farmers for its soil fertility restoration ability of haricot bean because of its high leave biomass. FM + SL also good for soil fertility restoration issues, but sole sweet lupine treatment was inferior to all treatments under evaluation since it was not adapted to the localities. Consistent with this result the higher grain yield of pigeon pea was recorded from sole pigeon pea compared to a pigeon pea-millet intercropping system [22]. Cowpea (for livestock feed and soil improvement) and soybean (for market, crop rotation, and soil improvement) crops were well adapted and preferred by farmers at Guangua district though their grain is less preferred for home consumption. In overall evaluation criteria, FM + CP, FM + SB, FM + SL and FM + HB were selected as 1st, 2nd, 3rd, and 4th respectively at Guangua district (Table 3).
At South Achefer FM + SL was highly preferred for its high grain yield, soil fertility improvement (restoration) and its suitability for human and animal feed (sweet lupine grain is best animal feed for sheep/goat fattening as supplemental and farmers are using the grain to make stew as a protein source) (Table 4). FM + CP was secondly preferred due to its high grain yield, good adaptation of cowpea, and its goodness for soil fertility restoration while it is less preferred since its grain is not suitable for home consumption. Although it was good at soil fertility restoration issues, sole soybean treatment was inferior to all treatments under evaluation since it was not adapted to the localities. Sweet lupine both as a source of human food and livestock feed as well as soil fertility improvement) and cowpea (for livestock feed and soil fertility improvement through its grain is less preferred for home consumption) were well adapted and preferred by farmers at South Achefer district. In overall evaluation criteria, FM + SL, FM + CP, FM + HB and FM + SB were selected 1st, 2nd, 3rd, and 4th respectively at South Achefer district (Table 5).
At Guangua FM + CP decrease the grain yield of FM because the performance of cowpea in the intercrop system was better than other intercropped legumes this might be due to the climbing property of cowpea it aggressively dominates over the finger millet that suppresses the growth and tillering capacity of finger millet. At South Achefer, grain yield of FM + SB was very low as compared to the other legumes because soybean had high vegetative biomass which hinders the growth of finger millet. Plant height of finger millet was high when FM + SL due to higher branching capacity of sweet lupine which leads to lower light penetration into the plant's canopy and more interspecific competition to light absorption. Consistent with this result as the seed rate of legume crops increased from 25.0 to 75.0% finger millet grain yield in a mixture was reduced by 38.5% when FM intercropped with lupine [23]. This lower light penetration increases internode length, reducing stem thickness, and increasing plant height [24]. But plant height decreased when FM + HB probably due to low competition for the available light. At Guangua, tiller number decreased when FM + CP, but at South Achefer FM + SL decreased tiller capacity of finger millet as compared to sole finger millet due to the competion ratio of lupine. The CR (competitive ratio) of lupine was apparently much higher than CR of haricot bean when they were intercropped with finger millet [25]. In agreement to this result FM + lupine have narrow temporal niche differentiation resulting in less stability of TLO yield as the component crops were heavily competing for growth resources for a long period of time, this suggests that staggering of the planting and growing period of the finger millet and lupine under intercropped would probably play an important role in the success of crop mixtures [26].
At Guangua, the land equivalent ratio was greater than one that means intercropping of finger millet with all legumes was more advantageous over sole cropping. The maximum LER (1.37) was recorded when FM + HB. Thus, intercropping of FM + HB could save 0.37 ha of land in comparison to sole production. At South Achefer, the maximum LER 1.79 was recorded when FM + HB. However, FM + SB gave LER<1 indicating the negative effect of soybean on the growth and yield of the plants grown in mixtures [18]. Consistent with this result an ATER (area time equivalent ratio) below one was observed in wheat-pea intercropping27. Thus, it could be concluded that the intercropping of finger millet with legumes could be used for improving household food security to smallholder farmers by increasing the productivity of finger millet, land use efficiency except for intercropping finger millet with Soybean at South Achefer.
5. Conclusion
Generally, finger millet intercropping with those adapted legume crops was helpful to increase the productivity and food consumption diversity of farmers in the intervention areas. The performance of finger millet was low as compared to its potential both in the intercrop and sole crop at both locations due to high blast infestation (Necho was highly susceptible variety for blast). Cowpea and soybean crops were well adapted at Guangua district while sweet lupine and cowpea adapted at South Achefer district. Sole Sweet lupine and sole haricot bean at Guangua and sole cowpea and sole soybean in South Achefer were inferior compared to all other treatments. At Guangua finger millet intercropped with cowpea and soybean preferred by farmers as 1st, and 2nd and also had 27 % and 12% yield advantage as compared to sole finger millet so it recommended for Guangua and similar agro-ecologies as 1st, 2nd option. At South Achefer finger millet intercropped with sweet lupine and cowpea preferred by farmers as 1st, and 2nd and also had 38 % and 35% yield advantage as compared to sole finger millet so it recommended for South Achefer and similar agro-ecologies as 1st, 2nd option. For its applicability intercropping of finger millet with legumes needs spatial and temporal arrangements.
5.1. Significance statement
Intercropping is one of the sustainable intensification methods and an eco-functional practice which has been widely used to boost crop productivity, increase the land utilization ratio. Cereal-legume intercropping is a common practice in Sub-Saharan Africa aimed at minimizing risks associated with monoculture. Among cereal-legume intercropping systems, the combination of finger millet with pigeon pea, soybean, haricot bean and groundnut are the common farming practices in Sub-Saharan Africa specifically in Ethiopia. Based on a survey conducted on the cropping system of finger millet in major growing areas of the Amhara region particularly in West Gojjam and Awi zones most of the farmers produced finger millet as a sole crop or in rotation with maize and only a few farmers produced finger millet in rotation with lupine and soybean. They also apply a small arbitrary amount of inorganic fertilizers, due to unaffordability. Due to mono-cropping system rate of malnutrition in the area increased yearly b/c there is no practice on incorporating of legumes with the main crop and also absence of well nutrient legumes species in the area. Therefore, the search for low-cost and environmentally friendly alternatives to improve soil fertility and the yield of finger millet is imperative that is consistent with the current focus of global agriculture. However, the choice of compactable crops depends on plant growth habit, land, light, water, and fertilizer utilization. To bring a new finger millet-based cropping system, it is vital to see the integration of potential legume crops for intercropping with finger millet in major growing areas of the region. Therefore, based on the present findings at Guangua finger millet intercropped with cowpea and soybean preferred by farmers as 1st, and 2nd and also had 27 % and 12% yield advantage as compared to sole finger millet. At South Achefer finger millet intercropped with sweet lupine and cowpea preferred by farmers as 1st, and 2nd and also had 38 % and 35% yield advantage as compared to sole finger millet, respectively. So farmers can easily intercrop the selected legumes to boost the productivity and fertility of the soil as well as decreasing malnutrition by incorporating those legumes in their feeding habit. For its applicability intercropping of finger millet with legumes needs spatial and temporal arrangements.
Declarations
Author contribution statement
Bitwoded Derebe: Conceived and designed the experiments; Performed the experiments; Analyzed and interpreted the data; Wrote the paper.
Abebe Worku: Conceived and designed the experiments; Performed the experiments.
Yazie Chanie: Performed the experiments; Analyzed and interpreted the data.
Andualem Wolie: Contributed reagents, materials, analysis tools or data.
Funding statement
This work was supported by CCRP McKnight foundation project (Rebecca J. Nelson of Cornell University and Jane Maland Cady of the McKnight Foundation), The Amhara Agricultural Research Institute, and Adet Agricultural Research Center.
Data availability statement
Data will be made available on request.
Declaration of interests statement
The authors declare no conflict of interest.
Additional information
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References
- 1.Laurent B., Hauggaard-Nielsen H., Naudin C., CorreHellou G. Ecological principles underlying the increase of productivity achieved by cereal-grain legume intercrops in organic farming. A review. Agron. Sustain. Dev. 2015;35(3):911–935. [Google Scholar]
- 2.Getachew A., Amare G., Woldeyesus S. Yield potential and land-use efficiency of wheat and faba bean mixed intercropping. Agron. Sustain. Dev. 2008;28:257–263. [Google Scholar]
- 3.Chu G.X., Shen Q.R., Cao J.L. Nitrogen fixation and N transfer from peanut to rice cultivated in aerobic soil in the intercropping system and its effect on soil N-fertility. Plant Soil. 2004;263:17–27. [Google Scholar]
- 4.Zhang F., Li L. Using competitive and facilitative interactions in intercropping systems enhances crop productivity and nutrient use efficiency. Plant Soil. 2003;248:305–312. [Google Scholar]
- 5.Zhang L.Z., van der Werf W., Bastiaans L., Zhang S.P., Li B.G., Spiertz J.H. Light interception and utilization in relay intercrops of wheat and cotton. Field Crop. Res. 2008;107:29–42. [Google Scholar]
- 6.Thilakarathna S., Raizada N. A review of nutrient management studies involving finger millet in the semi-arid tropics of Asia and Africa: Review. Agronomy. 2015;5:262–290. [Google Scholar]
- 7.Jasem A., Ahmad G. Biological facilitative interactions and their roles on maximize growth and productivity of crops in intercropping systems. Scient. Agricult. 2014;6(2):90–95. [Google Scholar]
- 8.Awol A., Masresha F., Kassahun T. Agromorphological, physiological, and yield-related performances of Finger Millet [Eleusine coracana (l.) Gaertn.] Accessions evaluated for drought resistance under field condition. Asian J. Agric. Rural Dev. 2013;3(10):709–720. [Google Scholar]
- 9.Minale L., Tilahun T., Alemayehu A. Seventh Eastern and Southern Africa Regional Maize Conference, Addis Ababa, Ethiopia. 2001. Determination of nitrogen and phosphorus fertilizer levels in different maize-faba bean intercropping patterns in northwestern Ethiopia; pp. 513–518. [Google Scholar]
- 10.Yayeh B., Getachew A., Enyew A., Alemayehu A. Nutrient competition and requirement in finger millet-haricot bean intercropping system. J. Plant Nutr. 2019;43(4):578–593. [Google Scholar]
- 11.Lekawunt Y., Kijora C., van Santen E., Peters K.J. Sweet Annual Lupine (Lupinus spp.); their adaptability and productivity in different agro-ecological zones of Ethiopia. J. Anim. Sci. Adv. 2012;2(2):201–215. [Google Scholar]
- 12.Crews T.E., Peoples M.B. Legume versus fertilizer sources of nitrogen: ecological tradeoffs and human needs. Agric. Ecosyst. Environ. 2004;102(3):279–297. [Google Scholar]
- 13.Brintha I., Seran T.H. Effect of paired row planting of radish (Raphanus sativus L.) Intercropped with vegetable amaranthus (Amaranthus tricolor L.) on yield components of radish in sandy regosol. J. Agric. Sci. 2009;4:19–28. [Google Scholar]
- 14.JICA (Japan International Cooperation Agency) 2015. Guideline to Participatory Agricultural Research through Farmer Research Groups (FRGs) for Agricultural Researchers, Revised in March 2015, Project for Enhancing Development and Dissemination of Agricultural Innovation through Farmer Research Groups (FRG II), Ethiopia; p. 90. [Google Scholar]
- 15.Anchala Chimdo. 2008. A Practical Guide to Farmers Research Groups, Ministry of Agriculture and Rural Development Rural Capacity Building Project (RCBP), Ethiopia. [Google Scholar]
- 16.SAS (Statistical Analysis system) 2001. The SAS Guide, SAS Version 9.0 Ed. Cary, North. [Google Scholar]
- 17.Gomez K.A., Gomez A.A. John Wiley & Sons; New York, NY: 1984. Statistical Procedures for Agricultural Research. [Google Scholar]
- 18.Mead R., Willey R.W. The concept of a land equivalent ratio and advantages. Exp. Agric. 1980;16:217–226. [Google Scholar]
- 19.Zhang G., Zaibin Y., Shuting D. Interspecific competitiveness affects the total biomass yield in an alfalfa and corn intercropping system. Field Crop. Res. 2014;124:66–73. [Google Scholar]
- 20.Kutrata T. A study on the farming system in USSA. Quart. J. Agro. Eco. 1986;26:179–205. [Google Scholar]
- 21.Dariush M., Ahad M., Meysam O. Assessing the land equivalent ratio (LER). Of two corn (Zea mays L.) varieties intercropping at various Nitrogen Levels in KARAJ, Iran. J. Cent. Eur. Agric. 2006;7(2):359–364. [Google Scholar]
- 22.Prasannakumar B.H., Halikatti S.I., Ninganur B.T. Sustainable intercrop association of pigeon pea (Cajanus cajan) in little millet (Panicum sumatrence L.) Karn. J. Agricult. Sci. 2009;22:887–888. [Google Scholar]
- 23.Yayeh B., Getachew A., Enyew A., Alemayehu A. Boosting land use efficiency, profitability and productivity of finger millet by intercropping with grain legumes. Cogen. Food Agricult. 2019;5:1–22. [Google Scholar]
- 24.Otteson Brian N., Mohamed Mergoum, Ransom Joel K. Seeding rate and nitrogen management effects on spring wheat yield and yield components. Agron. J. 2007;99(6):1615–1621. [Google Scholar]
- 25.Bitew Y., Alemayehu G., Adgo E., Assefa A. Competition, production efficiency and yield stability of finger millet and legume additive design intercropping. Renew. Agric. Food Syst. 2020:1–12. [Google Scholar]
- 26.Naudin C., Corre-Hellou G., Pineau S., Crozat Y., Jeuffroy M.H. The effect of various dynamics of N availability on winter pea–wheat intercrops: crop growth, N partitioning and symbiotic N2 fixation. Field Crop. Res. 2010;119:2–11. [Google Scholar]
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Data Availability Statement
Data will be made available on request.