BACKGROUND: An issue of pressing concern is the manganese contamination in farmland soils adjacent to industrial areas. To address this, intercropping hyperaccumulator plants with crops emerges as a sustainable approach to ensuring food security. This study aims to investigate the influence of intercropping Sedum alfredii with maize or soybean on their growth and the dynamics of manganese accumulation through field experiments.
RESULTS: The results showed that compared with monoculture, the Sedum alfredii-maize intercropping system exhibited a land equivalent ratio (LER) of 1.89, signifying a 71.13% augmentation in bioaccumulation amount (BCA). Additionally, it led to a significant reduction in manganese content in various organs, ranging from 17.05% to 25.50%. However, the Sedum alfredii-soybean intercropping system demonstrated a LER of 1.94, accompanied by a 66.11% increase in BCA, but did not significantly reduce the manganese content in the roots, stems, and pods of soybeans. Furthermore, manganese accumulation in maize and soybean grains was primarily attributed to the aboveground translocation of manganese. The intercropping effect on blocking manganese absorption of maize during growth and maturity is primarily attributed to the earlier manganese accumulation in intercropped maize by 2.63 to 4.35 days, and a reduction of 21.95% in the maximum manganese accumulation rate.
CONCLUSIONS: The study found that manganese accumulation dynamics vary significantly depending on the crop family. Intercropping Sedum alfredii with maize enhances land-use efficiency and reduces manganese uptake by crops, making it a promising strategy for remediating manganese-contaminated farmland near industrial areas. © 2024 Society of Chemical Industry.

Intercropping systems have garnered attention as a sustainable agricultural approach for efficient land use, increased ecological diversity in farmland, and enhanced crop yields. This study examined the effect of intercropping on the kiwifruit rhizosphere to gain a deeper understanding of the relationships between cover plants and kiwifruit in this sustainable agricultural system. Soil physicochemical properties and bacterial communities were analyzed using the Kiwifruit-Agaricus blazei intercropping System. Moreover, a combined analysis of 16S rRNA gene sequencing and metabolomic sequencing was used to identify differential microbes and metabolites in the rhizosphere. Intercropping led to an increase in soil physicochemical and enzyme activity, as well as re-shaping the bacterial community and increasing microbial diversity. Proteobacteria, Bacteroidota, Myxococcota, and Patescibacteria were the most abundant and diverse phyla in the intercropping system. Expression analysis further revealed that the bacterial genera BIrii41, Acidibacter, and Altererythrobacter were significantly upregulated in the intercropping system. Moreover, 358 differential metabolites (DMs) were identified between the monocropping and intercropping cultivation patterns, with fatty acyls, carboxylic acids and derivatives, and organooxygen compounds being significantly upregulated in the intercropping system. The KEGG metabolic pathways further revealed considerable enrichment of DMs in ABC transporters, histidine metabolism, and pyrimidine metabolism. This study identified a significant correlation between 95 bacterial genera and 79 soil metabolites, and an interactive network was constructed to explore the relationships between these differential microbes and metabolites in the rhizosphere. This study demonstrated that Kiwifruit-Agaricus blazei intercropping can be an effective, labor-saving, economic, and sustainable practice for reshaping bacterial communities and promoting the accumulation and metabolism of beneficial microorganisms in the rhizosphere.

The growing demand for higher-quality food production in smaller soil areas points to optimized land use. Intercropping has the potential to increase yield, reduce pests and diseases, and boost biodiversity. This study, conducted at the Institute of Horticulture, Lithuanian Research Centre for Agriculture and Forestry, from 2017 to 2019, aimed to determine the effect of white cabbage intercropping with aromatic plants, calendula, French marigold, thyme, and sage on yield, mineral and biochemical composition. Aromatic plants are known to reduce the occurrence of pests and diseases, so this study aimed to determine whether aromatic plants affect the yield, mineral, and biochemical composition of white cabbage. The two-year observations demonstrated that aromatic plants did not affect or slightly affect the mineral composition of cabbage\'s primary macronutrients (N, P, K, Mg, and Ca). Cabbage\'s dry matter, sugars, and ascorbic acid content vary when grown intercropped with aromatic plants compared to monoculture. Although the results were comparable, sugar concentration was lower in all cabbage combinations than in monoculture. Lower nitrate levels were detected in cabbage monoculture, probably due to agro-meteorological circumstances. The highest cabbage yield was achieved by intercropping with thyme (7.25 t/ha) compared to monoculture (6.81 t/ha) in 2018. It was found that intercropping with aromatic plants had little effect on the biochemical composition of white cabbage. The study results suggest that French marigold and thyme can be grown together with white cabbage to improve the phytosanitary of vegetables without compromising the biochemical quality of the cabbages. However, the influence on biochemical composition, especially on the nitrate and glucosinolate levels, should be examined further, providing valuable insights for future research in this field.

Nitrogen (N) content affects aboveground maize growth and nutrient absorption by altering the belowground rhizospheric ecosystem, impacting both yield and quality. However, the mechanisms through which different N supply methods (chemical and biological N supplies) regulate the belowground rhizospheric ecosystem to enhance maize yield remain unclear. To address this issue, we conducted a field experiment in northeast China, comprising three treatments: maize monocropping without N fertilizer application (MM), maize/alfalfa intercropping without N fertilizer application (BNF), and maize monocropping with N fertilizer application (CNS). The MM treatment represents the control, while the BNF treatment represents the biological N supply form, and CNS treatment represents the chemical N supply form. In the autumn of 2019, samples of maize and rhizospheric soil were collected to assess parameters including yield, rhizospheric soil characteristics, and microbial indicators. Both BNF and MM significantly increased maize yield and different yield components compared with MM, with no statistically significant difference in total yield between BNF and CNS. Furthermore, BNF significantly improved N by 12.61% and available N (AN) by 13.20% compared with MM. Furthermore, BNF treatment also significantly increased the Shannon index by 1.90%, while the CNS treatment significantly increased the Chao1 index by 28.1% and ACE index by 29.49%, with no significant difference between CNS and BNF. However, CNS had a more pronounced impact on structure of the rhizosphere soil bacterial community compared to BNF, inducing more significant fluctuations within the microbial network (modularity index and negative cohesion index). Regarding N transformation pathways predicted by bacterial functions, BNF significantly increased the N fixation pathway, while CNS significantly increased assimilatory nitrate reduction. In CNS, AN, NO3-N, NH4-N, assimilatory nitrate reduction, and community structure contributed significantly to maize yield, whereas in BNF, N fixation, community structure, community stability, NO3-N, and NH4-N played significant roles in enhancing maize yield. While CNS and BNF can achieve comparable maize yields in practical agricultural production, they have significantly different impacts on the belowground rhizosphere ecosystem, leading to different mechanisms of yield enhancement.

Faba bean wilt disease is a key factor limiting its production. Intercropping of faba bean with wheat has been adopted as a prevalent strategy to mitigate this disease. Nitrogen fertilizer improves faba bean yield, yet wilt disease imposes limitations. However, faba bean-wheat intercropping is effective in controlling wilt disease. To investigate the effect of intercropping under varying nitrogen levels on the incidence of faba bean wilt disease, nutrient uptake, and biochemical resistance in faba bean. Field and pot experiments were conducted in two cropping systems: faba bean monocropping (M) and faba bean-wheat intercropping (I). At four nitrogen levels, we assessed the incidence rate of wilt disease, quantified nutrient uptake, and evaluated biochemical resistance indices of plants. The application of N decreased the incidence rate of wilt disease, with the lowest reduction observed in intercropping at the N2 level. N application at levels N1, N2, and N3 enhanced the content of N, P, K, Fe, and Mn as well as superoxide dismutase (SOD), phenylalanine ammonia lyase (PAL), and polyphenol oxidase (PPO) activities and defense gene expression in monocultured plants. Additionally, these levels increased the contents of total phenols, flavonoids, soluble sugars, and soluble proteins, and all reached their maximum in intercropping at the N2 level. The application of intercropping and N effectively controlled the occurrence of faba bean wilt disease by promoting nutrient absorption, alleviating peroxidation stress, and enhancing resistance in plants.
UNASSIGNED: The online version contains supplementary material available at 10.1007/s12298-024-01466-1.

Lamiaceae is a botanical family rich in aromatic species that are in high demand such as basil, lavender, mint, oregano, sage, and thyme. It has great economical, ecological, ethnobotanical, and floristic importance. The aim of this work is to provide an updated view on the aerobiology of species from the family Lamiaceae, with an emphasis on novelties and emerging applications. From the aerobiology point of view, the greatest interest in this botanical family is related to the volatile organic compounds emitted by the plants and, to a much lesser extent, their pollen. Research has shown that the major volatile organic compounds emitted by the plants from this botanical family are monoterpenes and sesquiterpenes. The most important monoterpenes reported across studies include α-pinene, β-pinene, 1,8-cineole, menthol, limonene, and γ-terpinene. Most reports tend to cover species from the subfamily Nepetoideae. Volatile oils are produced by glandular trichomes found on aerial organs. Based on general morphology, two main types are found in the family Lamiaceae, namely peltate and capitate trichomes. As a result of pollinator-mediated transfer of pollen, Lamiaceae species present a reduced number of stamens and quantity of pollen. This might explain the low probability of pollen presence in the air from these species. A preliminary synopsis of the experimental evidence presented in this work suggests that the interplay of the organic particles and molecules released by these plants and their environment could be leveraged for beneficial outcomes in agriculture and landscaping. Emerging reports propose their use for intercropping to ensure the success of fructification, increased yield of entomophilous crops, as well as in sensory gardens due to the therapeutic effect of volatiles.

With mounting demand for high-quality agricultural products and the relentless exploitation of arable land resources, finding sustainable ways to safely cultivate food crops is becoming ever more important. Here, we investigated the effects of the integrated cropping technique \"straw return + intercropping\" on the soil aggregates as well as the microbial biomass carbon (MBC) content, enzyme activities and microbial diversity in soils of maize and soybean crops. Our results show that in comparison to straw removal and monoculture, straw return and intercropping increase the rhizosphere\'s MBC content (59.10%) of soil, along with urease (47.82%), sucrase (57.14%), catalase (16.14%) and acid phosphatase (40.66%) activities as well as the microbial diversity under maize and soybean. Under the same straw treatment, the yield of maize when intercropped surpassed that when grown in monoculture, with the land equivalent ratio of the intercropping treatment under straw return being highest. Overall, the intercropping of maize and soybean is beneficial for the healthy development of sustainable agriculture in the black soil region of northeast China, especially when combined with straw return to fields.

Intercropping leads to different plant roots directly influencing belowground processes and has gained interest for its promotion of increased crop yields and resource utilization. However, the precise mechanisms through which the interactions between rhizosphere metabolites and the microbiome contribute to plant production remain ambiguous, thus impeding the understanding of the yield-enhancing advantages of intercropping. This study conducted field experiments (initiated in 2013) and pot experiments, coupled with multi-omics analysis, to investigate plant-metabolite-microbiome interactions in the rhizosphere of maize. Field-based data revealed significant differences in metabolite and microbiome profiles between the rhizosphere soils of maize monoculture and intercropping. In particular, intercropping soils exhibited higher microbial diversity and metabolite chemodiversity. The chemodiversity and composition of rhizosphere metabolites were significantly related to the diversity, community composition, and network complexity of soil microbiomes, and this relationship further impacted plant nutrient uptake. Pot-based findings demonstrated that the exogenous application of a metabolic mixture comprising key components enriched by intercropping (soyasapogenol B, 6-hydroxynicotinic acid, lycorine, shikimic acid, and phosphocreatine) significantly enhanced root activity, nutrient content, and biomass of maize in natural soil, but not in sterilized soil. Overall, this study emphasized the significance of rhizosphere metabolite-microbe interactions in enhancing yields in intercropping systems. It can provide new insights into rhizosphere controls within intensive agroecosystems, aiming to enhance crop production and ecosystem services.

UNASSIGNED: Microbial carbon (C) and nutrient limitation exert key influences on soil organic carbon (SOC) and nutrient cycling through enzyme production for C and nutrient acquisition. However, the intercropping effects on microbial C and nutrient limitation and its driving factors between rhizosphere and bulk soil are unclear.
UNASSIGNED: Therefore, we conducted a field experiment that covered sugarcane-peanut intercropping with sole sugarcane and peanut as controls and to explore microbial C and nutrient limitation based on the vector analysis of enzyme stoichiometry; in addition, microbial diversity was investigated in the rhizosphere and bulk soil. High throughput sequencing was used to analyze soil bacterial and fungal diversity through the 16S rRNA gene and internal transcribed spacer (ITS) gene at a phylum level.
UNASSIGNED: Our results showed that sugarcane-peanut intercropping alleviated microbial C limitation in all soils, whereas enhanced microbial phosphorus (P) limitation solely in bulk soil. Microbial P limitation was also stronger in the rhizosphere than in bulk soil. These results revealed that sugarcane-peanut intercropping and rhizosphere promoted soil P decomposition and facilitated soil nutrient cycles. The Pearson correlation results showed that microbial C limitation was primarily correlated with fungal diversity and fungal rare taxa (Rozellomycota, Chyltridiomycota, and Calcarisporiellomycota) in rhizosphere soil and was correlated with bacterial diversity and most rare taxa in bulk soil. Microbial P limitation was solely related to rare taxa (Patescibacteria and Glomeromycota) in rhizosphere soil and related to microbial diversity and most rare taxa in bulk soil. The variation partitioning analysis further indicated that microbial C and P limitation was explained by rare taxa (7%-35%) and the interactions of rare and abundant taxa (65%-93%).
UNASSIGNED: This study indicated the different intercropping effects on microbial C and nutrient limitation in the rhizosphere and bulk soil and emphasized the importance of microbial diversity, particularly rare taxa.

Pulse crops have become more important in food production and consumption systems for the transition towards sustainability. We present an agroecological dataset from 304 samples from 12 legume field trials in five locations across three countries in the Mediterranean. The field trials were established in the seasons 2021/22 and 2022/23 and tested different lentil or chickpea cultivars, inoculants, intercropping and weeding regimes. The dataset encompasses detailed information on wild flora diversity, grain yield, associated management practices, soil texture and weather during the growing period. Wild flora diversity was recorded by conducting a vegetation survey in 1 × 2 m sample plots. Grain yield was determined at the crop maturity stage, with full plots harvested in Spain, while samples were taken in Croatia and Tunisia. Environmental variables were via laboratory analysis or bottle testing of soil samples and analysis of local weather data. The comprehensiveness of the dataset, including all relevant agroecological information, enables other researchers to employ the dataset for various statistical analyses of agroecosystem processes, such as plant-environment interactions or biodiversity-yield trade-off analysis.