Intercropped Maize Research Articles

Anti-drift performance of a hoods spray system for soybean (Glycine max (L.) Merr.)-maize (Zea mays L.) strip intercropping

Soybean (Glycine max (L.) Merr.)-maize (Zea mays L.) strip intercropping is a way to enhance land utilization efficiency, water conservation, and nutrient optimization, but there are few dedicated high-efficiency sprayers. Consequently, the objective of this research was to design a spray system tailored for the strip intercropping of maize and soybean and test its performance. The system consisted of 5 soybean units and 4 maize units, the soybean units consisted of nozzles and a hood, and the maize unit consisted of nozzles and booms. The anti-drift performance of the hoods with different heights and the spray deposition on plants were evaluated. The results demonstrated that the droplet drift increased with higher moving speed, spray pressure, and hood height. In the spray system performance experiment, the droplet deposition rates of soybean ranged from 40% to 50%, while for maize, they ranged from 50% to 68%. This spray system, specifically designed for soybean-maize strip intercropping, uses hood spray and hanger booms to isolate different pesticides and offers valuable technical support for enhancing crop yield, environmental protection, and resource conservation.

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.

Effects of Soil Tillage on the Agronomic Performance of Maize-Soybean Intercropping in Dry Land North Lombok, Indonesia By IJISRT

If land processing techniques on dry land are not carried out correctly, it can cause soil erosion and poorer soil fertility. Therefore, one way that can be done to prevent the soil from becoming sour is through proper soil processing accompanied by the addition of bio- ameliorants to the soil. This research aims to determine the effect of soil tillage on the agronomic performance of corn and soybean intercropping on dry land in North Lombok, Indonesia. The research was conducted from May to July 2023 in Pemenang Barat Village, Pemenang District, and North Lombok Regency. The study used an experimental method in the field using a randomized block design by testing five tillage techniques, i.e., Oo: without tillage; O1: without tillage, only sprayed with pre-growth herbicides before planting; O2: minimum tillage is only hoeing; O3: simple tillage and leveling; and O4: intensive tillage by hoeing, loosening, and leveling. The results showed that treatment-intensive and complete processing can increase the growth performance and biomass yield of maize and soybean intercropping. Treatment-intensive and complete processing can improve the performance of intercropping maize and soybeans in the dry land of North Lombok. To improve the agronomic performance of maize-soybean intercropping in the dry land of North Lombok, the best results are obtained using intensive and complete processing accompanied by the addition of bio-ameliorant at a dose of 15 tons per ha.

Growth and Productivity of Maize (Zea mays L.) as Influenced by Precision Nutrient Management and Intercropping Cowpea (Vigna unguiculata L.) under Hot and Sub-humid Region of Odisha

Background: Cereal-legume intercropping is an age-old practice in most of the countries. Among the major cereals, maize is a better choice to include in legume intercropping due to its morphology and wider row spacing. Therefore, legume intercropping in consort with proper nutrient management can enhance overall productivity of the system, further improving crop diversification, nutritional security and agriculture sustainability. Considering these aspects, the present study was performed to examine the growth and productivity of maize as influenced by precision nutrient management and cowpea intercropping. Methods: The present study was carried out during rabi season of 2022-23 at P. G. Research Farm of M.S. Swaminathan School of Agriculture, Odisha, India. The experiment was laid out in split-plot design with five intercropping combinations and five nutrient management treatments. All the treatments were replicated thrice. The plot size maintained was 5.0 m x 4.8 m. In case of maize and cowpea, high yielding hybrid ‘JKMH 4510’ and ‘KBC 9’ variety were taken for the study, respectively. Result: The results revealed that the growth parameters were significantly affected by intercropping ratios and nutrient management treatments. Although the yield attributes of maize were differed non significantly among the intercropping treatments but were significantly influenced by the nutrient treatments. In case of grain yield of maize, the Green Seeker-based nutrient management gave highest value with cowpea intercropping ratio of 1:1 and 2:2. LER and ATER were greater than unity, which indicated that the intercropping was advantageous. However, the maximum LER and Area Time Equivalent Ratio (ATER) were obtained from C3 (M+C 1:2) with 140:70:70 kg N, P2O5, K2O/ha, respectively. The study concluded that intercropping of maize + cowpea in 1:2 row ratio with Green Seeker-based nutrient management were advantageous over pure stand of maize fertilised with conventional nutrient management.

The proliferation of beneficial bacteria influences the soil C, N, and P cycling in the soybean-maize intercropping system.

Soybean-maize intercropping system can improve the utilization rate of farmland and the sustainability of crop production systems. However, there is a significant gap in understanding the interaction mechanisms between soil carbon (C), nitrogen (N), and phosphorus (P) cycling functional genes, rhizosphere microorganisms, and nutrient availability. To reveal the key microorganisms associated with soil nutrient utilization and C, N, and P cycling function in the soybean-maize intercropping system, we investigated the changes in soil properties, microbial community structure, and abundance of functional genes for C, N, and P cycling under soybean-maize intercropping and monocropping at different fertility stages in a pot experiment. We found that there was no significant difference in the rhizosphere microbial community between soybean-maize intercropping and monocropping at the seeding stage. As the reproductive period progressed, differences in microbial community structure between intercropping and monocropping gradually became significant, manifesting the advantages of intercropping. During the intercropping process of soybean and maize, the relative abundance of beneficial bacteria in soil rhizosphere significantly increased, particularly Streptomycetaceae and Pseudomonadaceae. Moreover, the abundances of C, N, and P cycling functional genes, such as abfA, mnp, rbcL, pmoA (C cycling), nifH, nirS-3, nosZ-2, amoB (N cycling), phoD, and ppx (P cycling), also increased significantly. Redundancy analysis and correlation analysis showed that Streptomycetaceae and Pseudomonadaceae were significantly correlated with soil properties and C, N, and P cycling functional genes. In brief, soybean and maize intercropping can change the structure of microbial community and promote the proliferation of beneficial bacteria in the soil rhizosphere. The accumulation of these beneficial bacteria increased the abundance of C, N, and P cycling functional genes in soil and enhanced the ability of plants to fully utilize environmental nutrients and promoted growth.

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.

Optimizing row combinations of an intercrop of maize with cabbage

In order to explore the optimum row combinations of an intercrop of maize with cabbage, 11 treatments for different intercropping rows of two crops were conducted from 2010 to 2016. The intercrop made intercropped maize yield raise and intercropped cabbage yield lower compared with their respective monocultures. Intercropped maize and cabbage interacted with each other, which could be presented by the regression equations between YIR, income and LER, and the number of intercropping rows of both maize and cabbage. Although the positive effect of intercropped maize could not offset negative effect of intercropped cabbage in the same intercropping rows, the advantage of the intercrop appealed when intercropping strip of cabbage was 1–3 rows more than that of maize. Income of cabbage monoculture was higher than that of maize monoculture and the intercrop. LER of the intercrop was relatively low with a maximum of 1.08. There was possibility that LER was ≥1 when the intercropping strip of cabbage was ≥ 4 rows. M4||C7 is recommended for an optimum combination of this intercrop based on the highest average LER value, and the opportunity for farmers to plant and harvest these rows with machinery.

The effectiveness of intercropping and agri-environmental schemes on ecosystem service of biological pest control: a meta-analysis

Plant diversification contributes to the ecological intensification of agroecosystems through pest biocontrol services provision. However, the existing evidence for the effectiveness of plant diversification in enhancing pest biocontrol services is highly uncertain across features of plant diversity and biodiversity characteristics. We undertook a comparative meta-analysis focusing on three essential crops (wheat, maize, and soybean) to investigate how diversification schemes in-field (intercropping) and Agri-environmental scheme (AES) around the field (flower strip, hedgerow and field margin) affect arthropod abundance. A random effects analysis was used to determine the role of 10 key factors underlying the effectiveness of plant diversification including biodiversity level and habitat, main and companion plant species, intercropping arrangement, the growth stage of the main crops, type of AES planting scheme, AES planting width, distance from AES plantings and geographical latitude. The overall results revealed that intercropping reduced herbivore and boosted predators and parasitoids abundance significantly, while AES successfully increased predators but not herbivores. Maize intercropping with legume and non-legume plants and row intercropping allowed for effective pest management. The abundance of predators increased in wheat fields immediately adjacent to planting around the field (AES), but this effect declined beyond 5 m from the flower strips. Our results suggest that the response of arthropod abundance to plant diversification is a compromise between spatial management scale, ecological characteristics of arthropod and plant diversification features. These results offer promising pathways for optimizing plant diversification schemes that include functional farm biodiversity across spatial and temporal scales and designing multi-functional landscapes.

Intercropping in maize silage versus solo‐seeding for alfalfa establishment in Wisconsin and Idaho

AbstractAlfalfa (Medicago sativa L.) intercropping with maize (Zea mays L.) silage is being developed in the northern United States to improve the profitability and environmental sustainability of forage production. This study, conducted under rainfed conditions in Wisconsin and semiarid irrigated conditions in Idaho, compared the establishment of alfalfa and dry matter yield of four intercropping systems to three conventional systems. The former systems included alfalfa interseeded at planting or the vegetative emergence (VE) stage of maize and grown with or without prohexadione growth retardant. The latter systems included alfalfa seeded in spring, summer‐seeded after barley (Hordeum vulgare L.), or late summer‐seeded after maize silage. Spring seeded and interseeded alfalfa in Wisconsin also received foliar fungicide and insecticide during establishment. During alfalfa establishment, yield of intercropped maize silage was 1.8‐ to 4.4‐fold greater than spring‐seeded alfalfa. Compared to spring‐seeded alfalfa, interseeded alfalfa had similar or somewhat lower stand density but similar first cut yield the following year, provided that intercropped maize was harvested near September 1 to allow ample alfalfa fall regrowth. Shifting interseeding from maize planting to the VE stage decreased early‐season alfalfa growth, but improved maize silage yield, with minor effects on alfalfa fall growth, stand density, and first cut yield. Prohexadione application had little impact on establishment or yield of interseeded alfalfa. While having high plant density, alfalfa seeded after barley or especially maize had less fall growth and low first cut yield. Overall, alfalfa establishment and yield of intercropping systems compared favorably with conventional systems.

Intercropped Maize and Cowpea Increased the Land Equivalent Ratio and Enhanced Crop Access to More Nitrogen and Phosphorus Compared to Cultivation as Sole Crops

Sub-Saharan African smallholder farmers face challenges due to limited access to commercial fertilizers, affecting food security. Exploring the benefits of intercropping is promising, but evaluating crop performance in specific agroecological contexts is crucial. This study in Vilankulo, Mozambique, conducted over two growth seasons (2018 and 2019), aimed to assess the benefits of intercropping maize (Zea mays L.) and cowpea (Vigna unguiculata L., Walp) (M+C) compared to maize (M) and cowpea (C) as sole crops. Key variables for comparison included dry matter yield (DMY), land equivalent ratio (LER), competitive ratio (CR), tissue nutrient concentration, nutrient recovery, and apparent N fixation (ANF). This study also examined the effects on cabbage (Brassica oleracea L.), cultivated as a succeeding crop, and soil properties. In 2018, maize plants were severely affected by drought and did not produce grain. This year, cowpea grain yields were 2.26 and 1.35 t ha−1 when grown as sole crop or intercropped. In 2019, maize grain yield was 6.75 t ha−1 when intercropped, compared to 5.52 t ha−1 as a sole crop. Cowpea grain yield was lower when intercropped (1.51 vs. 2.25 t ha−1). LER values exceeded 1 (1.91 and 1.53 for grain and straw in 2019), indicating improved performance in intercropping compared to sole crops. In 2019, CR was 1.96 for maize grain and 0.58 for cowpea grain, highlighting the higher competitiveness of maize over cowpea. Cowpea exhibited higher average leaf nitrogen (N) concentration (25.4 and 37.6 g kg−1 in 2018 and 2019, respectively) than maize (13.0 and 23.7 g kg−1), attributed to its leguminous nature with access to atmospheric N, benefiting the growth of maize in intercropping and cabbage cultivated as a succeeding crop. Cowpea also appears to have contributed to enhanced phosphorus (P) absorption, possibly due to access to sparingly soluble P forms. In 2019, ANF in M+C was 102.5 kg ha−1, over 4-fold higher than in C (25.0 g kg−1), suggesting maize accessed more N than could cowpea provide, possibly through association with endophytic diazotrophs commonly found in tropical grasses.

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.

Yield Test of Shade-Tolerant Maize Using the Intercropping Method of Maize-Soybean Under Coconut Trees

Maize is a light-dependent crop, but new varieties have been developed that can tolerate shade. This allows farmers to grow maize as an intercrop between coconut trees, making more efficient use of their land. Farmers can also intercrop with legume plants, which provide additional nitrogen through Rhizobium bacteria, leading to increased maize productivity. The aim of this study was to obtain the best intercropping pattern for maize and soybeans under coconut trees that results high yields in maize. The study was conducted in Padang Pariaman Regency of West Sumatra, at an altitude of approximately 150 meters, from February to July 2022. The experimental design was a Split Plot Design with Randomized Block Design, consisting of three main plot levels (planting time) and four subplot levels (planting model). The results of the study indicate that intercropping maize and soybeans under coconut trees has no effect on the weight of maize cobs, but there is a positive correlation between ear weight, cob length, cob diameter, number of rows per cob, and the weight of 1000 maize seeds.

Influence of different population densities of Bambara groundnut intercrop and weeding frequency on maize (<i>Zea mays</i> L.) performance

Effective weed management is essential for enhanced productivity of maize. A two-year field experiment was carried out at the Department of Crop Science Demonstration Farm, University of Calabar, Calabar, Nigeria (4.5-5.20 N, 8.0-8.30 E), in the 2019 and 2020 early planting seasons, to evaluate the influence of three population densities of Bambara groundnut [166,666 plants per hectare(B1), 100,000 plants per hectare (B2), 71,428 plants per hectare (B3)] and four hand weeding frequencies [weedy check (WC), one hand weeding (1HW), two hand weedings (2HW) and a weed free check (WFC)] on the performance of maize. The experiment consisted of three replications fitted into a Randomized Complete Block Design (RCBD). Data gathered on maize vegetative and yield characteristics were analysed using analysis of variance (ANOVA) procedures for RCBD (GenStat® statistical package, version 8.1). Significantly different means were compared at 5 % probability level using the Duncan’s New Multiple Range Test (DNMRT). From the results, maize growth and yield performance were significantly (P<0.05) affected by Bambara groundnut populations and the frequency of weeding. Leaving weeds unchecked all through the cultivation season hampered the vegetative and yield performance of maize, resulting in 47.54 % reduction in maize grain yield, compared with the weeded plots. Conclusively, intercropping maize with Bambara groundnut at 71,428 plants per hectare integrated with two hand weedings at 4 and 8 weeks after sowing (WAS), which optimized maize grain yield (3.87 t/ha on the two-year average) is recommended for farmers in the Calabar humid area and its environs.

Monocropping and Intercropping of Maize with Six Food Legumes at Malkerns in Eswatini: Their Effects on Plant Growth, Grain Yield and N2 Fixation, Measured using the 15N Natural Abundance and Ureide Techniques

Intercropping of legumes and cereals has many benefits to both plant partners. In this study, the effect of legume-maize intercropping on plant growth, grain yield and N2 fixation of six legumes was assessed using the 15N natural abundance and ureide techniques. For this, a field experiment involving six legume species and two cropping systems was established at the Malkerns Research Station, Eswatini during the 2017/2018 cropping season. Based on the 15N isotopic and ureide analysis, the six test legumes respectively obtained 39.06 – 70.19% and 16.46 – 55.79% of their N nutrition from symbiosis. The amounts of N-fixed ranged from 12.66 to 66.57 kg ha−1. In general, high amount of N-fixed by legumes correlated strongly with greater shoot dry matter accumulation (r = 0.7981; p < 0.001) and high grain yield (r = 0.5905; p < 0.001), indicating the importance of N2 fixation in plant growth and reproduction. Legumes grown under monocropping recorded higher plant growth, symbiotic performance and grain yield when compared to those grown in mixed culture with maize. However, shoot %Ndfa was much higher under intercropping than sole cropping due to competition by cereal and legume for soil N. Components of maize yield were similar for the two cropping systems. The %N derived from fixation and %relative ureide-N abundance were significantly correlated (r = 0.4005; p < 0.001), indicating that the 15N natural abundance technique and the ureide method were complementary in measuring N2 fixation in the test legumes. These results have provided some insights on the impact of cropping system on plant growth, symbiotic performance and grain yield of six selected legumes.

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.

Intercropping regulates plant- and microbe-derived carbon accumulation by influencing soil physicochemical and microbial physiological properties

Intercropping can increase soil carbon (C) sequestration and utilization by planting a variety of plants on a same land. However, the main plant and microbial-driven pathways leading to the increased C sequestration in intercropping soils are rarely studied. Therefore, it is important to reveal the distinct contributions of plant- and microbe-derived C to soil organic C (SOC) for understanding the regulation of intercropping in global C storage. Herein, two widely accepted sets of bio-markers, namely, amino sugars and lignin phenols, were employed to compare the distribution of plant- and microbe-derived C as well as their contributions to SOC in maize monoculture and intercropping systems, based on a field experiment established in 2013; meanwhile, the associations of soil physicochemical properties and microbial physiological traits with plant- and microbe-derived residues were disclosed via correlation and model analysis. Compared with the monoculture, maize intercropping significantly increased soil amino sugar and microbial necromass C contents as well as their contributions to SOC in maize mature stage; maize inter-planted with gingelly or soybean significantly increased these variables in the elongation stage; meanwhile, maize inter-planted with gingelly significantly increased soil lignin phenol content and its contribution to SOC in the mature stage. In all treatments and growth stages, microbial necromass C contributed more to SOC than lignin phenols, and fungal necromass C contributed more to SOC than bacterial necromass. The contribution of microbial necromass C to SOC was mainly influenced by amino sugar content, microbial C use efficiency, dissolved organic C content, and microbial biomass C content. The contribution of plant-derived C to SOC was mainly influenced by lignin phenol content, pH, and NH4+-N content. These results demonstrate the distinct regulations of maize intercropping on plant- and microbe-derived C to soil C pool by influencing soil physicochemical properties and microbial physiological traits, and meanwhile, highlight the potential of intercropping in global C storage.

Intercropping of Pteris vittata and maize on multimetal contaminated soil can achieve remediation and safe agricultural production

Soil contamination by multimetals is widespread. Hyperaccumulator–crop intercropping has been confirmed to be an effective method for arsenic (As)- or cadmium (Cd)-contaminated soil that can achieve soil cleanup and agricultural production. However, the influencing factors and response of hyperaccumulator–crop intercropping to multimetal-contaminated soil are still unclear. In this study, intercropping of the As hyperaccumulator Pteris vittata and maize was conducted on two typical types of multimetal-contaminated soil, namely, Soil A contaminated by As, Cd, and lead (Pb) and Soil B contaminated by As, Cd, and chromium (Cr). Intercropping reduced As, Cd, and Pb in the maize grains by 60 %, 66.7 %, and 20.4 %, respectively. The concentrations of As, Cd, Pb, and Cr in P. vittata increased by 314 %, 300 %, 447.3 %, and 232.6 %, respectively, relative to their concentrations in the monoculture plants. Two soils with different levels of contamination showed that higher heavy metal content might diminish the ability of intercropping to reduce soil heavy metal risk. No notable difference in soil microbial diversity was found between the intercropped and monocultured plants. The composition of microbial communities of intercropping groups were more similar to those of monoculture P. vittata on two different soils (Soils A and B). An imbalance between the amount of As taken up by the plants and the reduction in As in the soil was observed, and this imbalance may be related to watering, As leaching, and heterogeneity of soil As distribution. Reducing the risk resulting from As leaching and enhancing the efficiency of phytoextraction should be emphasized in remediation practices.

Facilitation between intercropped species increases micronutrient acquisition and controls rust disease on maize

Context or ProblemGlobal food security is threatened by plant disease, and crop diversification often promotes productivity through reduced disease and facilitation for increased nutrient acquisition. However, whether such facilitation is a factor in disease resistance is unknown. Objective or Research QuestionInvestigate how crop diversity affects crop productivity and rust disease on maize, and whether competition or facilitation between crop species correspond with resistance. MethodsFive irrigated intercropping experiments with different fertilization and crop combinations were conducted at two sites for four years. Productivity (542 data points) and disease severity (27150 data points) of maize monoculture, maize - legume and maize - non-legume intercropping were compared. A meta-analysis of literature was performed to confirm the broader applicability of results from these field experiments. ResultsLegume-based intercropping increased the aboveground biomass of intercropped maize by 8% and grain yields by 10% in comparison to non-legume-based intercropping. Disease severity on maize intercropped with legumes was reduced by 45% and 48%, compared to monocultures of maize and maize intercropped with non-legumes, respectively. Moreover, as interactions among intercrops became more facilitative, the concentrations of zinc (Zn), copper (Cu) and iron (Fe) in maize increased, and these increases were highly correlated with decreasing disease severity. The global meta-analysis was consistent with our field experiments, as lower disease severity was associated with greater intensity of interspecific facilitation or with lower intensity of interspecific competition. Conclusions or SignificanceLower disease severity was closely related to enhanced acquisition of nutrients that can enhance the resistance to crop diseases, driven by stronger interspecific facilitative effects in intercropping systems. Facilitative effects on maize was increased by the identity of leguminous companion crop species, and was increased by sufficient irrigation, but reduced by applications of nitrogen and phosphorus fertilizers. ImplicationsOur findings identify a novel facilitative mechanism in general and advance the understanding of the facilitative mechanisms that underly disease control through crop diversification.

Intercropping Maize-Faba Bean Reduced Yield and Economic Losses Caused by Busseola fusca (Fuller) in Semiarid Area.

Intercropping is an important practice for controlling crop pests in Ethiopia. However, there is a limited studies on the maize-faba bean intercropping benefits for controlling stemborer (Busseola fusca) pests. This study was carried out at Wukro Agricultural College, Tigray, Ethiopia, to investigate the effects of maize intercrops with two faba bean varieties (Gora and Moti) at three different population levels (25%, 50%, and 75%) of the recommended sole faba bean (250,000 plants ha-1) on infestation, density, and damage of stemborer on maize. The intercrops significantly (p < 0.05) reduced the stemborer infestation, density, and damage on maize over to the sole maize. Maize intercrops with the Gora faba bean variety at a density of 50% lowered the pest damage on maize cobs by 35% relative to the sole maize. The intercrop also reduced the grain yield and economic losses due to the pest by 48% and 53%, respectively, compared to the sole maize. The results recommended that maize intercropped with the Gora faba bean variety at a density of 50% could be used as an alternative farming against stemborer pest in the semiarid farming systems of northern Ethiopia.

Effect of Organic Nutrient Management and Intercropping of maize on the Soil Health of Acidic Soils of Mizoram

Effect of Organic Nutrient Management and Intercropping of maize on the Soil Health of Acidic Soils of Mizoram