Maize-legume Intercropping Research Articles

Impact of Rabi maize-legume intercropping system on growth, yield and crop competition in maize

Impact of Rabi maize-legume intercropping system on growth, yield and crop competition in maize

Effect of insecticides and intercropping systems on fall armyworm (Spodoptera frugiperda (J.E. Smith)) infestations and damage in maize in northern Ghana

Field studies were conducted over two successive seasons to test the effects of maize-legume intercropping system on fall armyworm (FAW) (Spodoptera frugiperda (J.E. Smith)) and if insecticide use was necessary in intercropping systems. Three insecticide treatments [no spray, Emastar 112 EC (a.i. emamectin benzoate 48 g/L + acetamiprid 64 g/L), Neem seed oil (NSO) (a.i. 3% azadirachtin)] and three intercropping systems [sole maize (Zea mays L.), maize + soybean (Glycine max (L.) Merr.) and maize + groundnut (Arachis hypogaea L.)] were arranged as a 3 × 3 factorial experiment in a randomized complete block design. Data were collected on FAW larval infestations, parasitism rates, damage, grain yield and gross financial returns. Results from combined-years analyses showed that larval infestation was significantly affected by intercropping (p = 0.034) only, with maize + soybean recording the lowest infestation while sole maize was highest. Damage to crop and cobs were significantly affected by years and insecticide treatments. Cob damage was also significantly affected by intercropping system with maize + soybean being lowest and sole maize recording the highest damage. Parasitoids recorded were Coccygidium luteum, Chelonus bifoveolatus, and Charops sp. Grain yield was significantly affected by the intercropping systems only (p = 0.004), with no significant year (p = 0.152), insecticide (p = 0.726) and insecticide × intercropping system (p = 0.660) effects. Sole maize (1.6 t/ha) had the lowest yield while maize + groundnut (2.2 t/ha) was highest. In terms of income, an economic analysis showed that spraying intercropped maize with NSO resulted in the highest marginal rate of return. Thus, the use of NSO and intercropping is an effective FAW management strategy.

Gendered Uptake of Sustainable Intensification Practices among Maize Commercializing Smallholder Farmers in Eastern Districts of Uganda

Commercialization of food crops, such as maize can dynamically shift control over productive resources or accrued income from women to men. This can restrict women’s ability to access or buy productive inputs. However, scanty information is available on how changing gender roles and relations can affect smallholder farmers’ use of sustainable intensification practices. This study described how gender inequalities in access to resources and appropriation of gains affect the uptake of sustainable intensification (SI) practices among maize commercializing farmers in eastern Uganda. Qualitative Survey data collected from a random sub-sample of 72 (36 women and 36 men) maize farmers from 584 maize commercializing smallholder farmers survey participants, was subjected to thematic content analysis. It was intended to follow up four unique profiles of farmers; those who did not use SI practices, the ones who used only intensification (improve maize varieties and fertilizers) or sustainable practices (organic manure and maize-legume intercrop), and those who used joint, one or more sustainable intensification practices. Findings revealed all four profiles to be highly gendered. Only women did not use any SI practice, and only men used intensification practices due to gender roles, responsibilities, and tasks shaped by traditions that give men terminal control over productive assets and gained resources. Both men and women used sustainable and sustainable intensification practices because of the negotiation process and opportunities that gave women more rights over resources. Thus, social-cultural histories and values constrain married women from implementing innovations such as SI practices because these values restrict women’s authority over productive resources. It is recommended that for inclusive transformative interventions to be introduced successfully in rigid patriarchal contexts, it is vital to enhance the negotiation skills of women.

Establishment of a high-yield intercropping system for maize and legumes under rainfed conditions in eastern Bhutan

ABSTRACT Maize-legume intercropping is a sustainable strategy to improve maize production for smallholder farmers. Maize is a staple food crop in Bhutan and integration of legumes with maize has been considered as an alternative option towards enhancing maize production in the country. Here, we conducted two studies in eastern Bhutan: first study (2021) to identify suitable legumes for intercropping with maize and second study (2022) to evaluate the effects of different maize-soybean intercropping patterns on grain yield, land use efficiency, and economic benefits. The maize-soybean intercropping system showed better productivity and economic viability than the kidney bean and groundnut systems in both the sites. Row intercropping and strip intercropping with 2 rows of maize alternating with 2 rows of soybean (2 M:2S) spaced 0.3 × 0.3 m showed stable and consistently higher grain yield at Lingmethang and Wengkhar (LING = 6.05 t ha−1; WENG = 8.37 t ha−1). The land equivalent ratio (LING = 1.78; WENG = 1.73) and net return (0.16 million Nu. ha−1 for LING and 0.21 million Nu. ha−1 for WENG) were notably higher for these intercropping methods. Our results suggest that the integration of legumes between conventional maize planting density, row intercropping and strip intercropping (2 M:2S) spaced at 0.3 × 0.3 m would be beneficial for achieving higher productivity for smallholder farmers in eastern Bhutan.

Shifting focus from external to in situ organic resources – The redesign of four tropical long-term experiments

Long-term experiments (LTEs) are critical for evaluating strategies that can maintain or increase crop yields, soil fertility and soil organic carbon (SOC), and help adapt to climate change. Yet, scientific knowledge is advancing and research questions are evolving. Therefore, it is important to review the objectives of LTEs over time. A change in their design may be necessary to keep the experimental treatments scientifically interesting, innovative, and relevant in the context of evolving agricultural challenges. Here, we describe the process of redesigning four LTEs in Kenya. These LTEs are unique in that they represent four different pedoclimatic conditions but with identical experimental treatments across sites. Initially, they focused on investigating how to maintain or increase SOC and maize yields over time by applying a combination of mineral nitrogen (N) and external organic resources. Specifically, the experimental treatments consisted of maize monoculture with different rates (1.2 and 4 t C ha−1 yr−1) and qualities of organic resources, either with or without mineral N fertilizer input. After about 20 years, it became clear that SOC was lost in most treatments. Therefore, continuing with the current experimental design was not an option. Taking advantage of the fact that the different former treatments led to different levels of soil degradation, we redesigned the LTEs to study the effectiveness of regenerative cropping strategies in rebuilding SOC and increasing crop yields starting from the different levels of soil degradation. The focus shifted from external to in situ organic inputs by increasing the root biomass of the cultivated crops. The newly established cropping system treatments are maize-legume rotation, maize-legume intercropping (double row configuration) and relay intercropping of maize with forage grass. A key finding from the previous phase of the experiments, namely, that external organic inputs with low C:N ratios are most efficient in building SOC, has been incorporated into the redesign. The relative contribution of external versus in situ organic resources is tested by splitting the cropping system treatments into those receiving either farmyard manure or green manure in the form of Tithonia diversifolia prunings and those receiving no external inputs. Split-plot treatments with and without mineral N were retained. The overall objective of studying mechanisms of tropical soil fertility maintenance and, more specifically, SOC formation, remained unchanged. However, the redesign aligned the LTEs with the current state of knowledge and pressing research questions, specifically focusing on the relative effectiveness of in-situ versus external organic inputs in SOC formation.

Prospects of maize-faba bean intercropping in monocropping highlands of Ethiopia.

Abstract Intercropping is an environmentally sustainable multiple cropping system widely practiced in small-scale farming communities in developing countries. Despite its high yielding potential, modern agriculture exploits the scarce agricultural land resources and contributes to the loss of biodiversity whilst intercropping diversifies species, increases and stabilises yield, and ensures food security. Maize-legume intercropping is a dominant cropping system in Ethiopia particularly in the lowlands but not common in the highlands where monocropping of small cereals is a traditional practice. It not only has the potential to break the disease cycle but can also be an additional source of income and food. This study was designed to evaluate the effects of proportion and arrangement of maize and faba bean intercrops on land use, cumulative yield and economic return. Here we show that intercropping increases cumulative productivity and profitability over years and ensures sustainability. Maize yield increased by 59% and 84% in the second and third years, respectively, while yield of faba bean declined by 67% in the second and third years. Sole maize had lower and sole faba bean had higher than their intercropping yields. The highest total LER of 2.11 was obtained from 100% maize: 75% faba bean combination which was equivalent to an additional 1.11 ha of land allocated to sole cropping. Overall, we recommend 100% maize: 25% faba bean for resource-limited farmers and 75% maize: 100% faba bean for commercial farmers based on the monetary advantage index. Moreover, 100% maize: 75% faba bean with acceptable monetary advantage was recommended for the commercial farmers.

How maize-legume intercropping and rotation contribute to food security and environmental sustainability

A revolution of cropping systems offers a promising opportunity to address complex and interconnected challenges to food security and environmental protection. Intercropping and crop rotation especially of legumes and maize are prominent candidates due to their wide applicability and advantages, given their differences in crop photosynthetic pathways. Scientific research on transition towards sustainable cropping systems continues to grow rapidly and there is an urgent need to systematize its knowledge map. Based on 6574 articles published from 1990 to 2022, we use bibliometric indicators such as publication trends, authorship patterns, and citation analyses to explore the research hotspots, frontiers and trends of maize-legume intercropping and crop rotation. The unbalanced research and practice patterns worldwide, different emphases between economic and environmental objectives of two cropping systems are analyzed. Finally, the potential and perspectives of the combination of intercropping and crop rotation to address challenges to food security and environmental sustainability are discussed.

Soil legacies in maize-edible legume intercropping alter maize growth and reduce Spodoptera frugiperda larval feeding

Plant-soil feedback can influence aboveground interactions between plants and herbivores by affecting plant chemistry. Such interactions can be utilized in pest management. However, cropping systems such as maize-legume intercropping (MLI) can influence these interactions which is not well understood. In this study, we explored effects of MLI systems on soil physico-chemical properties, maize growth, larval feeding and development of fall armyworm (Spodoptera frugiperda). We used sterile soil and soil conditioned by different MLI and maize-monoculture cropping systems to explore these interactions. Soil samples that included soil conditioned by different MLI and maize-monoculture cropping systems were collected from smallholder farmer fields in eastern Kenya, where different MLI and maize-monoculture cropping systems were being practiced. These soil samples were compared with sterile soils for physico-chemical properties using black oxidation and Walkley methods. Three-weeks-old maize plants grown in the different soil treatments in the greenhouse were used for larval feeding and development assays. Neonate S. frugiperda larvae were allowed to feed on maize leaf discs for 24 hours and another set of plants were inoculated with the neonates for 15 days and the larval survival and development monitored. Soil obtained from different maize-edible legume intercropping systems had a higher pH, electrical conductivity, nitrogen, organic carbon, potassium, phosphorus, calcium, magnesium, exchangeable acidity, copper, clay and silt compared to maize-monoculture and sterile soil. Maize plants grown in MLI soil had better growth parameters compared to those in maize-monoculture and sterile soils. A high correlation was found between pH and plant biomass, while no significant correlation with other physico-chemical properties was noted. There were significant differences in larval feeding by S. frugiperda neonates when exposed to constitutive and induced maize leaf discs with more leaf tissue fed on maize grown in maize-monoculture and sterile soil. When allowed to feed for 15 days, S. frugiperda larval weight and length were significantly lower on maize plants grown in soils conditioned by MLI than those grown in soil conditioned by maize-monoculture and sterile soils. Findings from this study show how conditioning soil by MLI systems improve soil health, maize growth and reduces S. spodoptera larval feeding and development.

Two crops are better than one for nutritional and economic outcomes of Zambian smallholder farms, but require more labour

Sustainable intensification practices suitable for smallholders in southern Africa will be needed to counteract the impact of future climate change and soil fertility decline in the region. Diversification of maize-based farming systems with grain legumes could play a key role. Here, we compared the performance of different maize-legume diversification strategies (single-row intercropping, strip cropping, and crop rotation) with sole cropped maize under conventional ploughing and Conservation Agriculture in four Zambian districts in the Eastern and Southern Provinces. These options were assessed using the Sustainable Intensification Assessment Framework (SIAF), with metrics representing productive, economic, human, social, and environmental dimensions. Data were collected from on-farm trials over three growing seasons. We found no significant effect of cropping systems on individual maize and legume grain yield across growing seasons, but substantial nutritional and economic benefits of intercropping systems due to simultaneously growing two crops. In particular, maize-legume intercropping strategies (single-row intercropping and strip cropping) resulted in higher energy and protein yield at cropping system level than sole maize and maize-legume rotation, which had positive implications for human nutrition. Although there were increased labour requirements to manage the intercrops, and particularly the strip crops, these cropping systems had much higher net benefits and returns to labour and inputs than the other cropping systems tested. Farmer evaluations however did not show a preference for the intercropping systems over the maize-legume rotation or sole maize, most likely because labour and its availability may be as or more important for farmers than overall cropping system benefits. Soil organic carbon content and soil pH did not differ between the tested cropping systems at the start of the trials and after three cropping seasons, but decreased over this period independently of the cropping system. Overall, the results indicate that maize-legume strip cropping, and single-row intercropping can increase food and nutrition security as well as gross benefits from farming, but this comes at the expense of greater labour requirements throughout the growing season. The latter may be addressed through, e.g., appropriate-scale farm mechanization, if intercropping or strip cropping systems are to become a viable option for labour, not land, constrained farms in Southern Africa.

Enhancing the Efficacy of Allium (Garlic) Extract and Maize-Legume Intercropping Agroecological Practices in Mitigating the Fall Armyworm Damage on Maize

Several biotic and abiotic variables limit the maize yield in Africa. The fall armyworm (FAW), a new invasive pest in Africa, and particularly in Cameroon, has exacerbated the problem. This study was done to demonstrate the fall armyworm control on maize in an intercrop system with legumes, and the locally made organic Allium (garlic) emulsion. In this study, a field experiment was laid out in a randomized complete block design with nine treatments (control, insecticide, Allium (garlic), maize dwarf-bean, maize-dwarf bean insecticide, maize-dwarf bean Allium (garlic), maize-cowpea, maize-cowpea insecticide and maize-cowpea Allium (garlic) and three replicates. Maize vegetative data (plant height, stem girth, and number of leaves) were collected, as well as pest occurrence and severity (fall armyworm) and maize yield. The best outcomes for the fall armyworm control in this study came from maize intercropped with legumes (dwarf bean and cowpea), in combination with either synthetic insecticides or the locally made organic garlic emulsion. Control had the most damaged plants for FAW (14) and the number of damaged plants differed significantly (P< 0.05) across treatments. The highest number of FAW (4 FAW) were found in the control, which differed significantly (P<0.05) across treatments. The maize grain yield ranged from 2.1 tha-1 to 5.7 tha-1 and differed significantly across treatments (P<0.05), with the highest yields (5.7 tha-1) in the maize-cowpea insecticide and maize-cowpea garlic treatments, and the lowest yields (2.1 tha-1) in the control. Conclusively, the maize intercrop with legumes and the locally made organic Allium (garlic) emulsion served as sustainable alternative to the synthetic pesticide that effectively controlled FAW without jeopardizing environmental sustainability and increased maize yield. Keywords: Allium (garlic) botanical, pest incidence, pest severity, fall armyworm (FAW), yield, maize, intercropping.

Maize-legume intercropping and botanical Piper mitigating effect on pest populations while enhancing the yield of maize

Climate change poses a wave of pests, devastating crops and jeopardizing the quest to feed more than 8 billion people globally. This can be seen in fall armyworm and snails being a nightmare to maize productivity. Thus this study was set up to increase maize productivity by reducing maize pests (FAW and snails) in maize-legume intercropping with locally produced organic (botanical) insecticide and utilizing legume nitrogen-fixing ability for maize growth and production. This work was done at the University of Buea and had nine treatments, and each was replicated three times in a randomized complete block design. The main crop maize, was intercropped with beans and cowpea. Data on fall armyworm incidence and severity, snail incidence and severity, height of plant, leaf number, girth of stem, leaf area index, and maize grain dry weight were collected. Data was subjected to ANOVA, P < 0.05, using SPSSv26 and graphs drawn with excel. More damaged plants for FAW and snails occurred in control, 14, and 11 plants, respectively, and were significantly different (P < 0.05) among treatments. The most pests were recorded in control 4 FAW and 3 snails per plant which varied statistically (P <0.05). Maize growth parameters (height of plant, leaf number, girth of stem, leaf area index) differed significantly (P < 0.05) across treatments, with control recording the least (206 cm, 13, 7.4 cm and 641 cm2 respectively). The best results were obtained with an intercrop of maize and cowpea along with synthetic or Piper pesticide. (236.4 cm, 16, 10.6 cm and 730.6 cm2 respectively) with no statistical difference. The highest maize yield was recorded in maize+cowpea intercrop coupled with Piper or synthetic insecticide (6.13 and 5.93 t/ha, respectively), with significant (P < 0.05) difference. Plant damage was connected adversely with yield (r = −0.90 for FAW, r = −0.94 for snail) and favourably with the number of pests (r = 0.70 for FAW, r = 0.86 for snail). ConclusionIntercropping and Piper emulsion effectively managed maize pests, while boosting maize output. As a result, farmers can utilize this maize-dwarf bean and maize-cowpea intercrop, as well as the organic Piper emulsion approach, as a sustainable crop protection and fertilizer management strategy to increase production.

Sustainable intensification and food security: A panel data assessment of the smallholder maize farmers in Uganda

Food security is touted as an essential condition for social growth. Yet, the food deficit is rampant among smallholder farmers in sub-Saharan Africa. Besides, farm productivity is considered the theme for improving household food security outcomes. As one of the sub-Saharan African countries, Uganda is affected by food insecurity caused by the declining availability of cropped farmland. Sustainable intensification (SI) is a critical farming practice that enhances crop yield and reduces environmental degradation. However, there is scanty empirical evidence on if farming practices contributing to sustainable intensification can improve the household livelihood and food security. In this research, we used multinomial endogenous treatment effects and a balanced Uganda National Panel Survey to evaluate the impacts of SI technologies on maize farming households' livelihood and food security. We ranked households into four groups depending on the inputs and soil management practices they use on their maize farms, namely “non-adopters”, intensification group”, “sustainable group”, and “sustainable intensification group”. The multinomial endogenous treatment effect (METE) model's findings suggested using the SI cluster is associated with improved food consumption score, household dietary diversity score, and per capita expenditure using non-adopters as the baseline group. Further, these improvements are determined by combining maize-legume intercrop and inorganic fertilizer practices. The results indicate that experts and researchers should espouse multidimensional and all-inclusive technological evaluation methods instead of conservative reductionists methods that concentrate on a solo farming practice at a time. Also, the findings can guide the sustainable vector that highlights and strengthens all-inclusive agricultural growth with policymakers and scientists working with marginalized farmers.

Double gains: Boosting crop productivity and reducing carbon footprints through maize-legume intercropping in the Yellow River Delta, China

The increasing demand for environmentally friendly agricultural practices has driven the need for diversified crop cultivation to optimize crop productivity while minimizing carbon footprints (CFs). However, the impacts of crop diversification on crop production and environmental benefits are still poorly understood. In this study, conducted at two sites in the Yellow River Delta, China, we investigated the effects of legume intercropping, specifically maize/soybean (M/S) and maize/peanut (M/P) systems, on crop productivity, economic return, ecosystem economic budget (NEEB), CF, and carbon sustainability index (CSI) in comparison to conventional monocrops. Crops were grown in replicated field plots and fertilized in their strips according to common practice for monocrops. Compared to the expected averages of monocrops, maize/legume intercropping demonstrated higher crop yields, with M/S achieving a 37% and 43% increase at the two sites, respectively, and M/P achieving an 11% and 20% increase. The higher overyielding in M/S was attributed to stronger selection effects, i.e., interspecific facilitation. However, the complementarity effects induced by the competitive dominance of maize were similar in both intercropping systems. Additionally, M/S exhibited greater potential for improving net revenues compared to M/P. Life cycle assessments revealed lower CFs in the intercropping systems compared to monocultures. M/S reduced CFs per unit of area by 26.8% at both sites, CFs per unit of maize equivalent energy yield by 25% and 33%, and CFs per unit of revenue by 20% and 25% at the two sites, respectively. M/P also resulted in reduced CFs, albeit to a lesser extent. Intercropping enhanced the CSI, with the highest values observed in the M/S system. However, both intercropping systems showed limited effects on soil C sequestration. Overall, our results highlight that maize/legume intercropping is a feasible approach to enhance crop productivity while reducing CFs. The M/S system outperformed the M/P system in terms of crop yields, economic benefits, and CF reduction. However, the intercropping systems showed limited effects on SOC storage. This study provides important implications for sustainable agriculture by appropriate crop diversification.

Maize-legume intercropping achieves yield advantages by improving leaf functions and dry matter partition

Intercropping can obtain yield advantages, but the mechanism of yield advantages of maize-legume intercropping is still unclear. Then, we explored the effects of cropping systems and N input on yield advantages in a two-year experiment. Cropping systems included monoculture maize (Zea mays L.) (MM), monoculture soybean (Glycine max L. Merr.) (MS), monoculture peanut (Arachis hypogaea L.) (MP), maize-soybean substitutive relay intercropping (IMS), and maize-peanut substitutive strip intercropping (IMP). N input included without N (N0) and N addition (N1). Results showed that maize’s leaf area index was 31.0% and 34.6% higher in IMS and IMP than in MM. The specific leaf weight and chlorophyll a (chl a) of maize were notably higher by 8.0% and 18.8% in IMS, 3.1%, and 18.6% in IMP compared with MM. Finally, N addition resulted in a higher thousand kernels weight of maize in IMS and IMP than that in MM. More dry matter accumulated and partitioned to the grain, maize's averaged partial land equivalent ratio and the net effect were 0.76 and 2.75 t ha−1 in IMS, 0.78 and 2.83 t ha−1 in IMP. The leaf area index and specific leaf weight of intercropped soybean were 16.8% and 26% higher than MS. Although soybean suffers from shade during coexistence, recovered growth strengthens leaf functional traits and increases dry matter accumulation. The averaged partial land equivalent ratio and the net effect of intercropped soybean were 0.76 and 0.47 t ha−1. The leaf area index and specific leaf weight of peanuts in IMP were 69.1% and 14.4% lower than in the MP. The chlorophyll a and chlorophyll b of peanut in MP were 17.0% and 24.4% higher than in IMP. A less dry matter was partitioned to the grain for intercropped peanut. The averaged pLER and NE of intercropped peanuts were 0.26 and -0.55 t ha−1. In conclusion, the strengthened leaf functional traits promote dry matter accumulation, maize-soybean relay intercropping obtained a win–win yield advantage, and maize-peanut strip intercropping achieved a trade-off yield advantage.

Unveiling the potential of maize-legume intercropping system for agricultural sustainability: A review

Intercropping offers a promising approach to enhance productivity in a given land area by simultaneously cultivating two or more crops together. Maize, a versatile cereal crop that can be seeded in widespread rows, presents an excellent prospect for growing another crop in between two rows. The coexistence of maize and legumes in an intercropping system brings about numerous benefits across various facets. The accomplishment of the maize-legumes intercropping system relies heavily on proper selection of crop species in mixed stands, considering factors such as their duration, plant stand per unit area, planting geometry and planting time. The advantages of adopting a maize-legume intercropping system are manifold. Firstly, it leads to higher yields and optimal utilization of available resources. Additionally, this system aids in weed, pest and disease management. Legumes play a crucial role by fixing biological nitrogen and transferring it to the associated maize plants, thereby contributing to nitrogen availability. Moreover, intercropping with legumes acts as an insurance against crop failure for smallholders and helps in restriction of soil erosion by covering a larger field area. The article focuses on the multifaceted benefits of the maize-legumes intercropping system, highlighting its potential to enhance agricultural productivity, resource utilization and sustainable farming practices.

A review of the impact of maize-legume intercrops on the diversity and abundance of entomophagous and phytophagous insects.

In many parts of the world, chemical pesticides are the primary method of pest control in maize (Zea mays L.) crops. Concerns about the negative consequences of chemical pesticide use on people's health and the environment, as well as the emergence of insecticide resistance, have accelerated attempts to discover alternatives that are effective, low-risk, and cost-effective. Maize-legume intercropping systems are known to have multiple benefits to agroecosystem functioning, including pest regulation. This review focuses on the influence of maize-legume intercropping systems on insect diversity and abundance as a mechanism for insect pest regulation in maize crops. First, this review combines knowledge of maize-legume intercrops, with a particular emphasis on the mechanism by which this practice attracts beneficial insects (e.g., predators, parasitoids) to reduce pest damage in intercropping systems. In addition, the pairings of specific legume species with the greatest potential to attract more beneficial insects and therefore reduce maize pests are also discussed. Finally, future research needs are also recommended. Findings are reviewed in the context of looking for long-term management strategies that can increase the adoption of integrated pest management programs in maize-based production systems.

The role of inter-specific competition for water in maize-legume intercropping systems in northern Tanzania

The role of inter-specific competition for water in maize-legume intercropping systems in northern Tanzania

Diversity of soil fertility management options in maize-based farming systems in northern Benin: A quantitative survey

Introduction: Maize-based production systems in Sub-Saharan Africa are largely based on family farming, which is characterized by low-input, nutrient-mining agriculture and practices. These systems usually promote soil degradation through loss of organic matter and erosion. The present study characterizes farms and main soil fertility management options in maize-based farming systems of the northern Benin.Methods: The study was conducted in the municipalities of Malanville, Banikoara and Bembèrèkè. We sampled randomly and interviewed 262 maize farmers, and the statistical analysis (distribution of means and frequencies, chi-square, ANOVA, etc.) was performed.Results and discussion: The results show that maize farming characteristics and socioeconomic conditions (land use and labor, production activities and land allocation, institutional arrangements on land, access to labor and capital, etc.) were diverse across locations and exhibited a wide variation within locations. Several practices were used for the management and sustainable maintenance of soil fertility in maize production systems in northern Benin: maize-legume intercropping, cotton-maize rotation, and mineral and organic fertilizers application. Most of farmers occasionally or regularly used mineral fertilizers (95.4%), followed by legume-cereal rotation/ intercropping (51.9%). Overall, 23.6% and 58.4% of farmers consistently used mineral fertilizer over the last 5 and 10 years, respectively. The amount of applied mineral fertilizer did not significantly vary between locations with an average (applied day after sowing, DAS) of 131.7 ± 13.7 (22 ± 8 DAS), 58.7 ± 9.6 (44 ± 5 DAS) and 164.7 ± 25.4 (38 ± 11 DAS) kg ha−1 for NPK, urea and Mix NPK + urea, respectively applied at, and days after sowing. Most farmers spread the fertilizer around the plants without covering with soil particles. Manure was applied exclusively to food crops through transporting and corralling (28.2%); and most farmers also used manure from their own livestock while few farmers used cattle corralling. Farmyard manure was mainly spread (100% of respondents) on the surface before plowing at the beginning of the rainy season. Maize farmers applied mineral fertilizer based on the level of initial soil fertility (naturally fertile or poor, degree of erosion etc.) and fertilizer purchase costs. Manure was not widely used as an alternative to chemical fertilizers; therefore, farmers need more strengthening and technical assistance on the production of organic fertilizers and manure storage. The findings are useful for policymakers on encouraging the successful implementation of sustainable soil fertility management strategies of maize-based farming systems in northern Benin.

Cost-Benefit Implications of Conservation Agriculture with Trees in the Dry Lands of Machakos County, Kenya

The adoption of conservation agriculture and agroforestry has been cited as the solution to the degradation and low profitability challenges in the drylands. The two systems have been known to result in high profitability through the improvement of yields and lowering of crop production costs. The study was carried out as part of ongoing experimentation established in the short rains (SR) season of 2012 by the World Agroforestry Centre in an on-station site at the Agricultural Training Centre (ATC) in Machakos County, Kenya. The trials were based on a split plot arranged in a randomised complete block design with two farming systems (conventional and conservation agriculture) serving as the main blocks, 10 treatments and three replicates, summing to a total of 60 plots. In the fields, three shrub species (Calliandra calothyrsus Meissn., Cajanas cajan (Pigeon pea), and Gliricidia sepium Jacq.) were planted in three different spacing (1.5 x 1 m, 3 x 1 m, 4.5 x 1 m) for maize-legume intercrops. The costs of production were recorded consistently in each season (LR 13, SR 13, and LR14). The maize and legume yields were valued at the market selling price from the local market, and a cost-benefit analysis was done through the calculation of benefit-cost ratios (BCR). The data was statistically analysed using ANOVA and means were separated using LSD at p &lt;0.05. Results showed significantly high BCR under conservation agriculture (p &lt;0.0001) in all seasons with sole CA having the highest BCR of 9.9 in LR 2014. The BCRs were lower in the first season due to high initial production costs, but this increased steadily in the succeeding seasons. The study concludes that conservation agriculture both with trees and as the sole is beneficial to the farmer, with higher net benefits compared to conventional tillage

Growth, productivity and economics of maize as influenced by maize-legume intercropping system ​

Maize (Zea mays L.) cultivation is catching up in India to fulfil the future demand. Odisha is a non-traditional state for maize cultivation; however, it has been intensified in the state during last one and half decades. As maize is a wide spaced crop, the inter row space allows to grow the short statured crops such as legumes. Maize - legume intercropping system is one of the most important intercropping systems followed worldwide. In this regard, a field experiment on paired row maize intercropping with legumes, namely, groundnut (Arachis hypogaea L.) and green gram (Vigna radiata L.) was carried out at Agronomy Research Farm of the Centurion University of Technology and Management, Odisha during rabi season of 2020. The experiment was laid out in a Randomized Complete Block Design (RCBD). There were nine treatments with pure stands of maize, groundnut and green gram and their mixed stand which were replicated thrice. The results revealed that the plant height at harvest and number of leaves of maize at 90 days after sowing (DAS) did not differ by cropping systems, whereas sole maize resulted in significantly higher dry matter production at all the growth stages and the same treatment registered significantly more leaf are index at 60 DAS. The yield attributes such as number of cobs/plant, cob length, number of rows/cob, number of grains/row, 100 grain weight and grain weight/cob remained on par, but number of grains/cob and grain weight per plant were significantly higher with sole maize than intercropped maize. The treatment comprised of maize + groundnut (2:3) intercropping system registered the highest net returns of Rs. 83590/ha. The findings suggested that in south Odisha conditions, intercropping maize + groundnut (2:3) can be adopted for better net return and agricultural sustainability compared to sole maize cultivation.