Sole Maize Research Articles

Rice Under Dry Cultivation–Maize Intercropping Improves Soil Environment and Increases Total Yield by Regulating Belowground Root Growth

Under the one-season-a-year cropping pattern in Northeast China, continuous cropping is one of the main factors contributing to the degradation of black soil. Previous studies (on maize–soybean, maize–peanut, and maize–wheat intercropping) have shown that intercropping can alleviate this problem. However, it is not known whether intercropping is feasible for maize and rice under dry cultivation, and its effects on yield and soil fertility are unknown. A three-year field-orientation experiment was conducted at Jilin Agricultural University in Changchun city, Jilin Province, China, consisting of three cropping regimes, namely rice under dry cultivation–maize intercropping (IRM), sole rice under dry cultivation (SR), and sole maize (SM). All straw was fully returned to the field after mechanical harvesting. Rice under dry cultivation–maize intercropping with a land-equivalent ratio of 1.05 (the average of three years values) increased the total yield by 8.63% compared to the monoculture system. The aggressivity (A), relative crowding coefficient (K), time–area-equivalent ratio (ATER), and competition ratio (CR) value were positive or ≥1, also indicating that the rice under dry cultivation–maize intercropping had a yield advantage of the overall intercropping system. This is because the intercropped maize root length density (RLD) increased by 33.94–102.84% in the 0–40 cm soil layer, which contributed to an increase in the soil porosity (SP) of 5.58–10.10% in the 0–30 cm soil layer, an increase in the mean weight diameter of soil aggregates (MWD) of 3.00–15.69%, an increase in the geometric mean diameter of soil aggregates (GMD) of 8.16–26.42%, a decrease in the soil bulk density (SBD) of 4.02–7.35%, and an increase in the soil organic matter content (SOM) of 0.60–4.35%. This increased the water permeability and aeration of the soil and facilitated the absorption of nutrients and water by the root system and their transportation above ground, and the plant nitrogen, phosphorus, and potassium accumulation in the intercropping system were significantly higher than that in monoculture treatment, further promoting the total yield of intercropping. This suggests that rice under a dry cultivation–maize intercropping system is feasible in Northeast China, mainly because it promotes belowground root growth, improves the soil environment, and increases the total yield of intercropping.

Zinc fortification and legume incorporation in forage based cropping systems: Implications for yield and nutrient dynamics

Aim: To evaluate the synergistic effects of legume intercropping and zinc fortification on forage yield, and plant and soil nutrient dynamics. Methodology: The experiment was laid out in a Factorial Randomized Block Design. Treatment combinations included five cropping systems, i.e., sole maize, sole cowpea, sole soybean, maize + cowpea (2:1), maize + soybean (2:1) and three zinc levels; Zn0= control or no zinc application, Zn1 = 20 kg ZnSO4 ha-1 (basal soil application) and Zn2 = 20 kg ZnSO4 ha-1 (basal soil application) + 0.5% ZnSO4 sprayed twice (30 DAS and 50 DAS). Results: Sole maize recorded highest dry matter (11938 kg ha-1) yield. Soil + foliar zinc application (Zn2) recorded an increase of 37.93 % increase in dry matter yield over control (Zn0). Maize + legumes recorded higher nitrogen uptake. There was an overall increase (122.34%) in zinc uptake from Zn0 to Zn2. Soil + foliar applied Zn increased ZnUE by 27.60 % (619.14 kg) over soil applied Zn (485.19 kg). Zn application increased Zn values of soil to 0.50 ppm with soil application and 0.56 ppm with soil + foliar application from the initial value of 0.36 ppm. Interpretation: Intercropping of legumes and application of 20 kg ZnSO4 as basal soil application plus two foliar applications of 0.5% ZnSO4 at 30 and 50 days after sowing significantly increased forage yield, nutrient uptake and enhanced soil zinc levels. Key words: Cropping systems, Intercropping, Legumes, Nutrient dynamics, Yield, Zn fortification

Effect of maize (zea mays l.) and cowpea (vigna unguiculata l.) intercropping on agronomic performance, yield and nutritional values of maize and cowpea under supplementary irrigation

A field experiment was conducted to evaluate the effect of maize (Zea mays L.) and cowpea (Vigna Unguiculata L.) intercropping on agronomic performance, yield, and nutritional values at Arba Minch University. Treatments were only maize crop (T1), only cowpea (T2), intercrop (maize and cowpea) in a 1:1 ratio (T3) and alternative rows of 2:2 (T4) as treatments. Treatments were arranged in a randomized complete block design (RCBD). Data on plant morphology, yield, nutritional composition, and economic return were recorded. The height of the plant (145.5 cm) of maize was significantly (P<0.001) higher at 1:1 intercropping than the height of the sole while the height of the cowpea was higher at the sole cropping. Higher number of branches (P <0.05) per plant (5.28) of cowpea was recorded in pure stands of cowpea than intercropping. The grain yield of maize (6.9 t/ha) and cowpea (4.2 t/ha) was significantly (P<0.05) higher in sole cropping than in intercropping. A higher dry matter yield of 9.06 t/ha of maize was obtained in a 1:1 maize- cowpea intercropping ratio than sole maize. Significantly (P<0.001) highest dry matter cowpea yield of 5.77 t/ha was obtained at sole cultivation than intercropping. The intercropping of maize with cowpea had an advantage of resource utilization in terms of land equivalent ratio (LER) 41.7% to 62.5%. The marginal rate of return (MRR) of intercropping in the ratio of 1:1 was as high as 48.23% in intercropping maize-cowpea, which was much better than sole cropping. Therefore, it could be recommended that the ratio of 1:1 maize-cowpea intercropping for land resource use and economic food and feed production in Arba Minch and similar agro-ecology zones.

Quantification of spatial-temporal light interception of crops in different configurations of soybean-maize strip intercropping.

Intercropping can improve light interception and crop yield on limited farmlands. The light interception rate in intercropping is determined by row configuration. Quantifying the spatio-temporal light interception of intercrops is very important for improving crop yields by optimizing the row configuration. A two-year field experiment was conducted at two sites to quantify the responses of the light interception rate of intercrops to five treatments: two rows of maize alternated with three rows of soybean (2M3S), two rows of maize alternated four rows of soybean (2M4S), two rows of maize alternated five rows of soybean (2M5S), sole soybean (SS), and sole maize (SM). We developed a multiple regression model based on the sine of the solar elevation angle (sin(h)) and crop leaf area density (LAD) to quantify the spatio-temporal light interception of intercrops. The predicted light interception rate was positively correlated with the measured values of photosynthetically active radiation (R2 > 0.814) and dry matter (R2 > 0.830). Increasing soybean rows led to an increase in light interception of both soybean and the lower layer of maize. However, this also resulted in a decrease in light interception in the upper layer of maize. At the two sites, compared to 2M3S, the annual average cumulative light interception of soybean in 2M5S increased by 44.73% and 47.18%, that of the lower layer of maize in 2M5S increased by 9.25% and 8.04%, and that of whole canopy of maize decreased by 13.77% and 17.74% respectively. The changes in dry matter and yield of intercrops were consistent with the change in light interception, which further verified the high accuracy of the light interception model. The annual average maize yield of 2M5S was 6.03% and 6.16% lower but the soybean yield was 23.69% and 28.52% higher than that of 2M3S. On the basis of system yield, the best performance was recorded in 2M4S at the two sites. In summary, the newly created light interception model performs well in the quantification of the temporal and spatial changes in crop light interception in strip intercropping and has potential applications in other configurations. Optimizing row configurations across climatic regions to enhance light interception and yield at the system level will become a future target.

Management of maize-legume conservation agriculture systems rather than varietal choice fosters human nutrition in Malawi

Malawi smallholder farmers are facing climate-induced challenges that have increased food and nutrition insecurity in the country, thus sustainable intensification practices has been widely recommended. The objective of this study was to assess the effects of cropping systems with improved varieties on total system productivity and nutrition under different environments. The study involved on-farm experiments in ten communities in Central and Southern Malawi, incrementally established from 2005/2006 to 2018/2019 cropping seasons. Each community had six demonstration plots with three main treatments: conventional ploughing (CP): sole maize grown on seasonally constructed ridges and furrows; no-tillage (NT): sole maize grown on retained ridges with minimum soil disturbance and residue retained; and Conservation agriculture (CA): maize intercropped either cowpea, pigeon pea or groundnut on retained ridges as in NT. Our results show that total system nutrition was higher in CA treatments than NT and CP. The yields of maize were at least 800 kg ha−1 higher in CA and NT than CP despite the variety that was grown. Legume yields were also higher under CA and NT than CP. High protein yield was observed in CA systems (at least 100 kg ha−1 higher than CP) where maize and legume intercrops were rotated with grain legumes. Our results show nutrients and energy gains in CA and NT systems that can be invested in practices that increases the resilience of smallholder farmers to climate change. Conservation agriculture and NT systems have more influence on productivity of smallholder farms, despite the genotypes used (hybrids or OPVs).

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.

Population Dynamics and Integrated Pest Management of the Fall Armyworm (FAW) Spodoptera frugiperda (JE Smith; Lepidoptera: Noctuidae) on Maize in Rivers State, Nigeria

Population dynamics and integrated pest management investigations of the fall armyworm (FAW) on maize conducted at the Faculty of Agriculture Teaching and Research farm, University of Port Harcourt, Rivers State Nigeria, made notable findings for the effective management of this notorious pest. This study involved 3 maize varieties namely Bende White (a local white variety), Oka (a local yellow maize) and Oba Super 98 (an improved white variety); two cropping patterns i.e. sole maize, and maize-yam intercrop; pheromonal trapping and pesticide (Kartodim 315EC). Pesticide applications were at 3 different phases (2WAP, 4WAP, and zero application as control, respectively). The pheromonal trap catches aided tracking of the pest’s population dynamics over the study duration showing the arrival times, build-up, peaks and falls. There was no significant difference in FAW populations between sole and intercrop plots; although 3 population peaks were found in maize-yam intercrop (at day 5, 7 and 17) against 2 peaks (day 4 and 15) in the sole maize. Oka variety showed significantly higher mean maize ear damages from FAW attacks (6.36 ± 2.45), compared to Bende (5.71 ± 2.87) and Oba 98 (4.77 ± 2.64) (p &lt; 0.05), implying that Oba 98 may be the best maize variety for cultivation in this locality.

Interplanted crops and rainfall variability regulate soil erosion in rainfed maize of the Indian Himalayas

AbstractSoil erosion is a serious threat to agriculture and environmental sustainability in the risk‐prone rainfed Himalayan ecosystem. Hence, runoff and soil loss mitigation ability of four maize‐based intensified systems; maize (Zea mays) + turmeric (Curcuma longa), maize + ginger (Zingiber officinale), maize + colocasia (Colocasia esculenta), and maize + sweet potato (Ipomoea batatas) were tested against the sole maize. The study recorded 41 erosive events during the 2020–2022 monsoon season. A principal component analysis (PCA) was performed to transform correlated rainfall parameters into orthogonal principal components. A two‐dimensional biplot analysis examined the relationship between PCs, rainfall events, and rainfall parameters. The rainfall events were divided into three regimes based on cluster analysis using PC. Rainfall regime 1 was characterized by low rainfall, I30, rainfall erosivity (E), and moderate rainfall duration (D), regime2 with moderate rainfall, short duration, high I30, and E, and regime3 with high D, I30, and rainfall erosivity. The soil loss of regime‐3 was 9.29 and 3.24 times higher than regime‐1 and regime‐2, respectively. Cover crops reduced runoff by 21.5%–69.3% and soil loss by 54.1%–77.0% over control. Redundancy analysis (RDA) showed that rainfall parameters (I30, I60, D, and E) had a significant direct influence across the systems, explaining 37.7%–54.9% of response variable variance, with E being the most influential (47.4%–54.9%), indicating varied impacts on runoff and soil loss. The sweet potato was best suited with maize as an intercrop to minimize soil erosion and maximize the system's profitability.

Intercropping of Maize and Cowpea for Enhancing Productivity, Profitability and Land use Efficiency

A field experiment was conducted at agriculture farm, ICAR-Central Institute for Research on Goats (CIRG), Makhdoom, Mathura, Uttar Pradesh during kharif season of 2020. The treatments consist of sole maize, sole cowpea; and intercropping of maize + cowpea in 1 : 1, 2 : 1, 1 : 2, 2 : 2, 3 : 1, 1 : 3 and 3 : 3 row ratios. The results revealed that maximum total green fodder yield, maize and cowpea equivalent yield, Land Equivalent Ratio (LER), Monitory Advantage Index (MAI), net returns and Benefit: Cost ratio were recorded with 2 : 1 row ratio of maize + cowpea intercropping combination followed by 3 : 1 row ratio. The highest value of nitrogen and potassium content both in fodder maize and cowpea were recorded with 1 : 3 row ratios of maize + cowpea intercropping combination. Further, the highest phosphorus content in fodder maize was recorded with 3 : 1 row ratio of maize + cowpea intercropping combination whereas in case of cowpea the highest phosphorus content was recorded with 1 : 3 row ratio of maize + cowpea intercropping combination. Thus, it was found that two rows maize + one row of cowpea (2 : 1) intercropping combination perform best in terms of yield, land use efficiency and profitability of fodder maize and cowpea. Bangladesh J. Bot. 53(2): 235-242, 2024 (June)

Border row effects improved the spatial distributions of maize and peanut roots in an intercropping system, associated with improved yield.

Border row effects impact the ecosystem functions of intercropping systems, with high direct interactions between neighboring row crops in light, water, and nutrients. However, previous studies have mostly focused on aboveground, whereas the effects of intercropping on the spatial distribution of the root system are poorly understood. Field experiments and planting box experiments were combined to explore the yield, dry matter accumulation, and spatial distribution of root morphological indexes, such as root length density (RLD), root surface area density (RSAD), specific root length (SRL), and root diameter (RD), of maize and peanut and interspecific interactions at different soil depths in an intercropping system. In the field experiments, the yield of intercropped maize significantly increased by 33.45%; however, the yield of intercropped peanut significantly decreased by 13.40%. The land equivalent ratio (LER) of the maize-peanut intercropping system was greater than 1, and the advantage of intercropping was significant. Maize was highly competitive (A = 0.94, CR=1.54), and the yield advantage is mainly attributed to maize. Intercropped maize had higher RLD, RSAD, and SRL than sole maize, and intercropped peanut had lower RLD, RSAD, and SRL than sole peanut. In the interspecific interaction zone, the increase in RLD, RSAD, SRL, and RD of intercropped maize was greater than that of intercropped peanut, and maize showed greater root morphological plasticity than peanut. A random forest model determined that RSAD significantly impacted yield at 15-60 cm, while SRL had a significant impact at 30-60 cm. Structural equation modeling revealed that root morphology indicators had a greater effect on yield at 30-45 cm, with interactions between indicators being more pronounced at this depth. These results show that border-row effects mediate the plasticity of root morphology, which could enhance resource use and increase productivity. Therefore, selecting optimal intercropping species and developing sustainable intercropping production systems is of great significance.

Intercropping in maize reduces fall armyworm Spodoptera frugiperda (J. E. Smith) infestation, supports natural enemies, and enhances yield

Fall armyworm (FAW) is a multi-generational invasive insect pest of maize. Field experiments were conducted in diverse ecologies at Hyderabad, Telangana (Location 1); Dholi, Bihar (Location 2); Kolhapur, Maharashtra (Location 3) during the rainy season from July-November, 2023 to assess the impact of maize intercropping with legumes and leafy vegetables on FAW damage, abundance of beneficial insects, weed dynamics, and yield. In the present study, location-specific intercrops were selected for the experimentation. In location 1, maize intercropped with cowpea followed by groundnut reduced the level of FAW infestation compared to sole maize. The increased natural enemy population (coccinellids, spiders, earwigs); weed suppression, and higher yields were observed in maize when intercropped with cowpea followed by groundnut and red amaranthus. In location 2, maize intercropped with cowpea followed by green gram and black gram reduced the FAW damage and higher natural enemy population. Maximum yield was obtained in maize intercropped with black gram followed by green gram and cowpea. However, concerning weed suppression and cost-benefit ratio, green gram followed by black gram was found to be superior. Minimum FAW infestation, abundant natural enemy population, weed suppression, and improved economic returns were observed in maize when intercropped with cowpea followed by groundnut and fenugreek in location 3. Each intercrop had its advantages concerning pests, weed suppression, an abundance of natural enemy populations, and higher yields. Therefore, it is suggested that the selection of plants as intercrops with maize should be based on the location-specific importance of particular aspects to attain multifunctional benefits. The present results revealed that crop diversification with location-specific intercrops can reduce significant yield losses caused by FAW and promote higher yields in maize.

Effect of Intercropping Spinach and Radish on Growth and Yield of Maize (Zea mays)

Background: Intercropping increases crop yield per unit area by intensifying the use of land. Cultivation of maize with leafy vegetables provides better use of land and other environmental resources, which results in higher economic yield. The current investigation aimed to study the effect of maize-spinach and maize-radish intercropping on growth and yield of maize under rainfed condition of Namsai district of Arunachal Pradesh. Methods: The field experiment was conducted during 2021 in randomized block design consisting of 3 treatments i.e. T1- Sole Maize, T2- Maize + spinach and T3- Maize + radish with four replications. Observations on growth and yield parameters and yield of maize were recorded on harvesting of the crop. The results were analysed using standard statistical procedures of ANOVA. Result: In maize + spinach and maize + radish intercropping, plant height (176.3 cm), numbers of leaves (15.49) and leaf area (5407 cm2 plant-1) were significantly greater in sole maize than the intercropping system. On the other hand, the yield parameters as well as yield of maize was higher in maize + radish intercropping as compared to maize + spinach and sole maize system. The grain yield of maize under maize + radish intercropping was 3066.25 kg ha-1. The B:C (1.92) was significantly higher in intercrops than the sole maize crop. From this study, it can be concluded that the intercrops are agronomically and economically viable than sole cropping. The intercropping of maize with radish would be profitable due to higher yield of maize as well as B:C (2 rows of maize and 2 rows of soybean) under farmer’s field condition of Namsai district of Arunachal Pradesh.

Plant spatial configurations and their influences on phenological traits of cereal and legume crops under maize‐based intercropping systems

AbstractIntroductionIntercropping systems have a great potential for crop diversification thus increasing smallholder systems' resilience to climate change while improving soil health. However, optimal benefits associated with intercropping systems are rarely realised because of the interspecific competition for growth resources among the intercropped species.MethodologySix trials were established in the high and low rainfall agroecological zones of Babati district in Tanzania to assess how promising cropping systems with different plant spatial configurations would influence the phenological development of intercropped maize, bean and pigeonpea. Cropping systems under study included a sole maize system rotated with a pigeonpea‐bean intercrop dubbed Doubled‐up legume (DUL), maize‐pigeonpea system both with and without de‐topping, an innovation comprising double maize rows alternated with pigeonpea and beans (Mbili‐Mbili), maize‐pigeonpea system with two maize seeds sown within a 50 cm intra‐row space, a vertical‐architecture Meru H513‐pigeonpea system and a farmer practice.ResultsBranch formation was significantly higher in DUL than in maize‐based systems (p ≤ 0.05). Seasonal weather had upto 30% influence on pigeonpea flowering, with DUL having highest (p ≤ 0.05) flower production. The rate of pigeonpea branch and flower production in Mbili‐Mbili was stable across seasons relative to other maize‐pigeonpea systems. Doubled‐up legume and farmer practice had pigeonpea litter yield of between 1 and 2 t ha−1 which was at least 0.5 t ha−1 higher than in maize‐based systems (p ≤ 0.05). During the period preceding early maize reproductive stages, Mbili‐Mbili increased light interception by 30% and 63% compared to maize‐based systems and DUL, respectively. Maize toppings had higher (94%) P content than stover biomass that remained until harvest.ConclusionOverall, maize‐legume systems had higher intercropping efficacy than sole maize system, both in interception use efficiency, soil mulch cover, among other soil health benefits. Mbili‐Mbili and DUL also had increased phenological benefits on intercropped legumes however, the latter was prone to seasonal weather variability.

Inter-cropping patterns and nutrient management effects on maize growth, yield and quality

ContextIntercropping, a sustainable agricultural practice, is pivotal in enhancing land use efficiency, soil fertility, and overall crop productivity. This study zeroes in on the dynamics of Maize-Cowpea intercropping in the Alluvial Zone of West Bengal, a region characterized by its fertile soil and diverse agro-ecological conditions. The practice of intercropping, particularly in regions like West Bengal, holds immense potential in revolutionizing traditional farming methods by maximizing yield per unit area while ensuring sustainability. The study aims to unravel the complexities and benefits of this practice, especially in the context of the monsoon dependent Kharif season, which is crucial for agricultural productivity in the region. ObjectivesThe study aims to evaluate the effects of various Maize-Cowpea intercropping patterns and nutrient management strategies on maize growth, yield, and quality during the Kharif seasons of 2019 and 2020. It hypothesizes that intercropping, combined with optimal nutrient management, can significantly enhance maize performance. MethodsEmploying a split-plot design, the study analysed 25 treatment combinations of intercropping and nitrogen fertilization under sub-tropical sub-humid conditions. Advanced quantitative methods, including regression analysis and principal component analysis (PCA), were used to assess the interactions between intercropping systems and nutrient management practices. ResultsThe findings revealed that while sole maize cultivation showed better growth and yield, Maize-Cowpea intercropping, especially in a 1:1 row ratio, significantly increased the total system yield by 13.6%. This method also improved grain quality, notably enhancing crude protein content and nutrient percentage. A combination of 75% recommended dose of nitrogen (RDN) through chemical means with 25% RDN through organic sources, including seaweed, was particularly effective in boosting maize performance. ConclusionsThe study confirms the superior performance of Kharif maize in an intercropping setup, particularly when integrated with cowpea. It demonstrates the effectiveness of specific nutrient management strategies in enhancing both quantitative and qualitative traits of maize. ImplicationsThis research significantly contributes to the field of sustainable agriculture, particularly in the context of field crops research and practice. The findings offer valuable insights for enhancing crop productivity and sustainability in similar agro-ecological regions globally. The study underscores the benefits of integrating legumes with cereals in intercropping systems, paving the way for innovative agricultural practices that can meet the dual challenges of food security and environmental sustainability. The implications of this research are far-reaching, providing a robust framework for future agricultural strategies in regions facing similar climatic and soil conditions.

Nutrient Uptake of Maize as Influenced by Intercropping with Different Genotype of Groundnut under Temperate Kashmir Valley

A field experiment on ‘Nutrient uptake of maize as influenced by intercropping with different genotype of groundnut under temperate Kashmir valley” was conducted at Sher-e-Kashmir University of Agricultural Sciences and Technology of Kashmir, Wadura, Sopore during 2021 and 2022. The experimental soil exhibited silty clay loam characteristics with adequate drainage and normal levels of both reaction and salinity. The experimental treatments comprised of sole crops and various row proportions of maize intercropped with groundnut. The experimental design was randomized complete block design, consist nineteen treatments that were replicated three times. Treatment comprised of T1 (Sole maize, 60 cm), T2 (sole paired maize, 75-45-75 cm), T3 (Sole paired maize,90-30-90 cm), T4 (Sole groundnut TG-84), T5 (Sole groundnut TG-37-A), T6 (Sole groundnut TG-88), T7 (Sole groundnut TG-89), T8 Alternate row of maize + groundnut TG- 84 (30 + 30 cm ),T9 Paired row of maize + groundnut TG- 84 (75-45-75 cm maize in between 25-25 cm groundnut),T10 Paired row of maize + groundnut TG- 84 (90-30-90 cm maize in between 30-30 cm groundnut), T11 Alternate row of maize + groundnut TG- 37-A (30 + 30 cm ) T12 Paired row of maize + groundnut TG- 37-A (75-45-75 cm maize in between 25-25 cm groundnut), T13 paired row of maize + Groundnut TG- 37-A (90-30-90 cm maize in between 30-30 cm groundnut), T14 Alternate rows of maize + Groundnut TG- 88 (30 + 30 cm),T15 Paired row of maize + groundnut TG- 88 (75-45-75 cm maize in between 25-25 cm groundnut), T16 Paired row of maize + groundnut TG- 88 (90-30-90 cm maize in between 30-30 cm groundnut), T17 Alternate rows of maize + groundnut TG- 89 (30 + 30 cm), T18 Paired row of maize + groundnut TG- 89 (75-45-75 cm maize in between 25-25 cm groundnut), T19 Paired row of maize+ groundnut TG- 89 (90-30-90 cm maize in between 30-30 cm groundnut). The two years of result revealed that intercropping increased the total N, P and K uptake and enhancing yield of both the crop. Total N, P and K uptake was recorded significantly higher with paired row of maize (75/45 cm spacing) in intercrop with groundnut variety TG-37-A as compared to sole maize. In intercrop N, P and K uptake was recorded significantly higher in sole groundnut variety TG-37-A followed by TG-84, TG-88 and TG-89.

Intercropping Maize with Faba Bean Improves Yield, Income, and Soil Fertility in Semiarid Environment.

Continuous adoption of improved maize varieties in the last three decades has changed farm landscapes from heterogeneity to maize homogeneity in semiarid areas of Ethiopia. This has substantially decreased maize productivity. Recently, farmers have integrated faba bean into maize-based farming systems aimed at increasing productivity. Yet, there is limited information on the effects of maize-faba bean intercropping on productivity and land-use efficiency. We studied the effects of maize intercrops with two faba bean varieties (Gora and Moti) at three different densities (25, 50, and 75%) of the recommended sole faba bean (250,000 plants ha-1) on yield, economic return, and some soil fertility indicators in Tigray, northern Ethiopia. Randomized complete block design with three replications was used for the experiment. The intercrops revealed that a significantly higher total grain yield, economic revenue, and land equivalent ratio (LER) over the sole cropping. Intercrops also showed higher soil organic carbon and total nitrogen compared to the preplanting soil and sole maize. Maize intercropped with the Gora faba bean variety at a density of 50% increased the total grain yields, economic return, and LER, respectively, by 13, 42, and 38% over the sole maize. The intercrop also increased soil total N by 55 and 22% compared to the preplanting soil and sole maize, respectively. Intercropping maize with faba bean significantly improved crop yield, income, land-use productivity, and some soil fertility indicators than either the sole maize or faba bean crop in the semiarid region of northern Ethiopia.

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.

Introduction of soybean into maize field reduces N2O emission intensity via optimizing nitrogen source utilization

The application of synthetic nitrogen (N) fertilizer has increased anthropogenic N2O emission in global croplands. Due to the advantage of biological nitrogen fixation (BNF), the introduction of legume may lessen N2O emission intensity (emission/yield) in cereal field. Yet, this speculation lacks strong evidences and the relevant mechanistic explanations. A two-year field study was conducted using static chamber method (15N isotope labeling in fertilizer) in the mono- and inter-cropping fields with soybean introduced in maize field in semiarid rainfed Loess Plateau. The results indicated that maize-soybean intercropping showed 13 % lower N2O emission intensity than monocropping, attributed to 14 % and 20 % lower annually N2O emissions in intercropped zone than that of sole maize and soybean zones respectively. Also, a 15 % higher grain yield was observed in intercropped maize relative to that in sole maize. Particularly, during the peak time of emission following N fertilization and BNF within growing season, soybean introduction reduced 25 % and 24 % of N2O emissions in intercropped zone than sole maize and soybean zone respectively. It also favored maize plant with an additional 17 % more fertilizer-derived N, 21 % less soil-derived N and 30 kg N ha−1 soybean transferred-N from BNF. The contributions of N fertilization, BNF and soil initial organic N to N2O production were lessened in intercropping. In this case, the capacity of substrates N transformation into N2O emissions was lowered. Critically, soybean introduction reduced soil ammonia oxidation (as evidenced from amoA AOA and AOB gene abundance) in intercrops’ rhizosphere, and increased soil nitrite reduction (nirS and nirK gene abundance) in maize rhizosphere, and improved soil N2O reduction to N2 (nosZ gene abundance) in soybean rhizosphere. Therefore, soybean introduction optimized N source use for lower N2O emission intensity, via reducing the transformation of substrate N into N2O, and modifying the expression of nitrification and denitrification functional genes.

Diversification of wheat-maize double cropping with legume intercrops improves nitrogen-use efficiency: Evidence at crop and cropping system levels

Context or problemThe sustainability of traditional maize-wheat (M-W) double cropping in the North China Plain (NCP) is threatened by excessive nitrogen (N) input and surplus. Meanwhile, there is strong market demand of more protein and oil crops, such as soybean or peanut. Incorporation of legumes into M-W via intercropping with maize is emerging in the NCP to foster China’s self-sufficiency for edible oils and proteins. Objective or research questionIt is unknown how such a change in cropping system affects the required annual fertilizer N input, and the resulting N-use efficiency (NUE) and N surplus (Ns). MethodsWe conducted a four-year field experiment involving four N fertilizer rates and rotations of winter wheat with six different summer crops: maize (conventional and density-increased), peanut (P), soybean (S), and intercrops of density-increased maize and peanut or soybean (MP, MS). The “three-quadrant diagram” and NUE proposed by the EU Nitrogen Expert Panel (EUNEP) were used to assess NUE at crop and cropping system level, respectively. ResultsLand equivalent ratios of N uptake in intercrops averaged 1.02–1.07 while N fertilizer equivalent ratios averaged 1.15–1.20, indicating more efficient N uptake and more yield per unit fertilizer than sole crops. Intercropped maize exhibited greater N acquisition efficiency than sole maize. Inclusion of intercrops lowered required annual N inputs and Ns and increased the apparent recovery efficiency (RE) of applied N and EUNEP-NUE. Soybean was a more productive and N-use efficient companion species for maize than peanut. Increasing N decreased RE and EUNEP-NUE while elevated Ns of all rotation systems. N productivity responses of each rotation system to increasing N followed a “linear-plateau” model. Compared to M-W with an optimal 240–360 kg N/ha, MS-W with 210–320 kg N/ha saved 11.1–12.5% fertilizer, increased N uptake by 12.4–16.0%, augmented RE from 36.0–37.0% to 47.8%, increased EUNEP-NUE from 0.50 to 0.67 kg/kg (within the target of 0.50–0.90 kg/kg), lowered Ns by 38.8–39.2%, and reduced N emission by 48.6–49.3%. ConclusionsTherefore, here we show for the first time, using multiple N performance indicators, that MS-W with moderate N provides diversified products, higher N productivity, NUE and lower N loss than M-W, thus being a suitable option for sustainable intensification of agricultural production. Implications or significanceSuch a diversified rotation approach with legume intercropping aligns with the principles of agricultural green development and has a global relevance for countries with sequential double cropping or rotation systems.

MAIZE AND SOYA BEAN RESPONSE TO THE RESIDUAL INFLUENCE OF EARLY-SEASON CROPPING SYSTEM AND FERTILISER APPLICATIONS

Continuous land cultivation has led to the application of fertilisers to maintain high crop yields. Favourable effects of different fertiliser sources for improved crop performance have been reported. However, there is scarce information on crop response to the residual effect of organomineral fertilisers (OMFs) applied to early sole and maize-soya bean intercropping. Consequently, the objective of this study was to evaluate the residual effect of N levels of organomineral and inorganic fertilisers applied to maize and soya bean in sole cropping and intercropping. The study was conducted in the years 2017 and 2018 in the Southern Guinea Savannah, Jalingo, Taraba State, Nigeria. Responses to the residual influence of early season cropping systems and applications of OMF and NPK 20-10-10 were evaluated in repeated field trials. The residual effects of a previously assessed 2 9 factorial arrangement, cropping system (sole and intercrop) and fertiliser applications (0, 50, 100, 150, 200 kg Nha of OMF and 50, 100, 150, 200 kg N ha of NPK fertiliser) were evaluated in a randomised complete block design with three replicates. Maize (ACR-95DT) and soya bean (TGX 1488-2E) were planted at densities of 40,000 and 74,000 plants ha, respectively. Data were analysed using ANOVA at p 0.05. Maize and soya bean plant heights and N uptake significantly increased under the residual influence of sole cropping compared to intercropping in both years. Furthermore, maize-soya bean intercropping produced significantly lower grain yields than their sole crops in both years. The land equivalent ratio of the system was greater than one in both years. The residual effect of early season intercropping reduced subsequent yields of maize and soya bean, while OMF residual effects favoured sole maize, sole bean, and maize-bean intercrop performances at 100 kg Nha.