Plant Interactions Research Articles

Evolution of Wolbachia reproductive and nutritional mutualism: insights from the genomes of two novel strains that double infect the pollinator of dioecious Ficus hirta.

Wolbachia is a genus of maternally inherited endosymbionts that can affect reproduction of their hosts and influence metabolic processes. The pollinator, Valisia javana, is common in the male syconium of the dioecious fig Ficus hirta. Based on a high-quality chromosome-level V. javana genome with PacBio long-read and Illumina short-read sequencing, we discovered a sizeable proportion of Wolbachia sequences and used these to assemble two novel Wolbachia strains belonging to supergroup A. We explored its phylogenetic relationship with described Wolbachia strains based on MLST sequences and the possibility of induction of CI (cytoplasmic incompatibility) in this strain by examining the presence of cif genes known to be responsible for CI in other insects. We also identified mobile genetic elements including prophages and insertion sequences, genes related to biotin synthesis and metabolism. A total of two prophages and 256 insertion sequences were found. The prophage WOjav1 is cryptic (structure incomplete) and WOjav2 is relatively intact. IS5 is the dominant transposon family. At least three pairs of type I cif genes with three copies were found which may cause strong CI although this needs experimental verification; we also considered possible nutritional effects of the Wolbachia by identifying genes related to biotin production, absorption and metabolism. This study provides a resource for further studies of Wolbachia-pollinator-host plant interactions.

Soil-structure interaction of nuclear power plant

Nuclear power plants are special facilities with large foundation designs, located in areas with good geology. However, in areas where seismic loads need to be considered, analyzing the soilstructure interaction of nuclear power plants is essential. Nonlinear analyses of soil-structure interaction can be performed in the time domain or frequency domain. Time domain analysis has the advantage of easily incorporating nonlinear material models or geometric nonlinearity. However, this method is limited by the boundary conditions of the geological region near the structure, as current analysis methods assume vertically propagating seismic waves towards the structure. This assumption is made to limit the errors that finite element methods can introduce at the boundaries. This paper presents a new computational method that combines finite element method and boundary element method, in which the propagation of seismic waves towards the structure can be considered at a predetermined angle. The paper analyzes the impact of wave propagation on the response spectrum of the Kashiwazaki-Kariwa Nuclear Power Plant Unit 7. The results of the analysis show that the new computational method can consider the influence of the angle of incoming wave on the soil-structure interaction analysis.

Insights into the molecular mechanism of Trichoderma stimulating plant growth and immunity against phytopathogens.

Trichoderma species have received significant interest as beneficial fungi for boosting plant growth and immunity against phytopathogens. By establishing a mutualistic relationship with plants, Trichoderma causes a series of intricate signaling events that eventually promote plant growth and improve disease resistance. The mechanisms contain the indirect or direct involvement of Trichoderma in enhancing plant growth by modulating phytohormones signaling pathways, improving uptake and accumulation of nutrients, and increasing soil bioavailability of nutrients. They contribute to plant resistance by stimulating systemic acquired resistance through salicylic acid, jasmonic acid, and ethylene signaling. A cascade of signal transduction processes initiated by the interaction of Trichoderma and plants regulate the expression of defense-related genes, resulting in the synthesis of defense hormones and pathogenesis-related proteins (PRPs), which collectively improve plant resistance. Additionally, advancements in omics technologies has led to the identification of key pathways, their regulating genes, and molecular interactions in the plant defense and growth promotion responses induced by Trichoderma. Deciphering the molecular mechanism behind Trichoderma's induction of plant defense and immunity is essential for harnessing the full plant beneficial potential of Trichoderma. This review article sheds light on the molecular mechanisms that underlie the positive effects of Trichoderma-induced plant immunity and growth and opens new opportunities for developing environmentally friendly and innovative approaches to improve plant immunity and growth.

Effect of plant traits and network metrics on pollen limitation in hummingbird-pollinated plants from the Brazilian Campos Rupestres

Pollen limitation (PL) can be an important estimate of the contribution of pollinators to the reproductive success of plants. PL often varies between species within the same community, and interspecific variation in PL may be related to plant traits and interaction patterns. However, few studies have investigated its drivers at the community level. In this study we assessed PL and its relationship with the dependence of plants on pollinators, floral morphology, nectar production and descriptors of the role of plant species in the interaction network in which they are embedded (linkage level, interaction strength, specialization and c or z coefficients) for 28 plant species pollinated by hummingbirds in the Brazilian Campos Rupestres. In the studied plant community, the prevalence of PL was high, but intensity was low, with 8 species (29 %) presenting some degree of PL. Nectar volume and nectar concentration were negatively related to PL, while plant species with higher dependence on pollinators for reproduction presented higher PL. We did not detect a relationship between network metrics and pollen limitation, this could reflect the low variation in species roles in the community, with most plant species being peripherals (linked to few and generalized pollinators). We demonstrated that plant traits were more important than network metrics in predicting interspecific variation in pollen limitation in the studied plant-hummingbird network. We suggest that evaluating pollen limitation within plant communities is key to uncover the drivers of pollination deficits.

Impact of soil residual auxin herbicide on seedling emergence and biomass differs between soil types, water pulse event, and seedling species

Synthetic‐auxin herbicides are often used to control woody plants and aid in grassland restoration. Seed‐based restoration is common alongside herbicide applications and there may be unintended effects of these herbicides on dryland plants at the seed and seedling stages. Additionally, abiotic conditions at the time of herbicide application may influence herbicide–soil–plant interactions. We conducted a greenhouse study to examine the effects of a common shrub‐control herbicide mix and its interaction with soil type and a post‐herbicide water pulse on common desert plant seeds and seedlings. In this greenhouse study, we found that a subset of species responded negatively to soil residual herbicide activity of a mixture of aminopyralid, clopyralid, and triclopyr at the seed and seedling stages. Species sensitive to soil herbicide residues were primarily shrub and forb species that are often the target species of herbicide applications for woody plant control, such as honey mesquite (Prosopis glandulosa) and creosote bush (Larrea tridentata). However, two shrub species (four‐wing saltbush [Atriplex canescens], soaptree yucca [Yucca elata]) and one perennial grass species (Arizona cottontop [Digitaria californica]), which are used in dryland restoration projects, were found to be particularly sensitive to soil residual herbicide activity. Thus, if using these herbicides to control woody plants and restore herbaceous vegetation via active seeding or relying on the in situ seed bank, considerations should be given to what species are used in the seed mix, what species are already present in the soil seed bank, and other details of the circumstances of herbicide application.

Community structure and niche differentiation of endosphere bacterial microbiome in Camellia oleifera.

Understanding the changes in bacterial community structure in different microenvironments of Camellia oleifera is essential to better explore the benign interaction between beneficial microorganisms and plants. Using Camellia oleifera trees, a Chinese wooden oil plant as a model ecosystem, we characterized the archaeal and bacterial microbiome across five different tissue-level niches using 16S rRNA gene analyses. Our research indicates that the diversity of Camellia oleifera endophytic bacterial communities is highly dependent on the plant compartment. The species replacement process (69.90%) is the dominant factor in the differences in bacterial community structure. The dominant bacteria phyla (Proteobacteria, Acidobacteria, Actinobacteria, Bacteroidetes, Firmicutes, Chloroflexi, and Verrucomicrobia) of Camellia oleifera show a significant plant compartment (roots, stems, leaves, fruits) enrichment effects. A variety of bacteria (Hymenobacter, Allorhizobium-Neorhizobium-Pararhizobium-Rhizobium, Mesorhizobium, Bradyrhizobium, Bacillus, Ochrobactrum, Pantoea, Pseudomonas, etc.) with nitrogen-fixed potentials are enriched in Camellia oleifera tissue. In addition, the hub bacterial groups of Camellia oleifera are Nitrospira, Haemophilus, Staphylococcus, Ruminiclostridium, and Ochrobactrum. They are widespread colonization in various tissues with a low relative abundance and may play an important role in the nitrogen cycle, host life promotion, and plant defense. This study provides a holistic understanding of the endosphere bacterial community structure, which is one of the most complete ecological niche-level analyses of Camellia oleifera. These results provide a scientific theoretical basis for an in-depth discussion of plant-endosphere microbial interaction and better exploration of benign interaction of beneficial microorganisms and plants.IMPORTANCEMicroorganisms inhabited various tissues of plants and play a key role in promoting plant growth, nutritional absorption, and resistance. Our research indicates that the diversity of Camellia oleifera endophytic bacterial communities is highly dependent on the plant compartment. Proteobacteria, Acidobacteria, Actinobacteria, Bacteroidetes, Firmicutes, Chloroflexi, and Verrucomicrobia are dominant bacteria phyla. The tissues of Camellia oleifera contain various bacteria with nitrogen fixation potential, host life promotion, and plant defense. This study provides a scientific theoretical basis for an in-depth discussion of plant-endosphere microbial interaction and better exploration of benign interaction of beneficial microorganisms and plants.

Spatial point pattern of the baobab (Adansonia digitata) in semi-arid savanna, Southeast Zimbabwe

Species distribution modelling based on bioclimatic variables to understand habitat suitability and changes in range dominates studies on the spatial distribution of baobabs, which limits our understanding of how the small-scale plant–plant interactions influence the spatial point pattern of this keystone species in semi-arid regions of sub-Saharan Africa. Here, we investigated the spatial distribution of the baobab in two protected areas, Chipinge Safari Area (CSA) and Save Valley Conservancy (SVC) which lie in the semi-arid Southeastern lowveld of Zimbabwe. CSA was previously a sparsely human populated area before its proclamation as a protected area, has a small number of herbivores and baboons, and has no elephants, while SVC has a high density of elephants (1.5 km−2) and large number of herbivores. At each site, 1 km2 plots, SVC (n = 4) and CSA (n = 3), were established for spatial analysis. In each plot, we recorded the spatial location, elevation, height, diameter at breast height, and canopy cover of each baobab. Spatial point-pattern was assessed using both the inhomogeneous transformed L-function for Ripley's K-function and the pair-correlation function. Baobabs in SVC were larger (height, canopy cover, and basal area) relative to those in CSA. At both sites, baobabs were clustered at small spatial scale (0–50 m), indicating that competition was insufficient to cause density-dependent thinning that can lead to even distribution as we expected. The distribution of small baobabs was independent of large baobabs, which reflects the importance of other environmental factors such as site conditions and seed dispersal rather than nurse-protégé on seedling establishment. The random distribution pattern of adult baobabs could be the legacy effects of these random factors and processes at establishment. Overall, our study shows that the distribution of baobabs is not dependent on local plant–plant interactions, but most likely from larger scale random pattern forming factors and processes such as seed dispersal and environmental heterogeneity.

Phylogenetic relatedness can influence cover crop-based weed suppression

Cover crops are plants grown to provide regulating, supporting, and cultural ecosystem services in managed environments. In agricultural systems, weed suppression services from cover crops can be an important tool to promote sustainability as reliance on herbicides and tillage for weed management has caused pollution, biodiversity loss, and human health issues. However, to effectively use weed suppression services from cover crops, farmers must carefully select species that fit within their rotations and suppress their problematic weeds. Understanding how the relatedness between cover crops and weeds affects their interactions will help farmers select cover crops for targeted weed management. The phylogenetic distance between species reflects their relatedness and was studied through a series of field experiments that compared weed suppression in winter and summer cover crops with tilled controls. This study demonstrates that cover crops can reduce up to 99% of weed biomass and alter weed community structure by suppressing phylogenetically related weed species. Results also suggest that cover crop planting season can influence weed community structure since only overwintering treatments affected the phylogenetic distance of weed communities. In an applied context, these results help develop cover crop-based weed management systems, demonstrating that problematic weeds can be managed by selecting phylogenetically related cover crop species. More broadly, this study provides a framework for evaluating weed communities through a phylogenetic perspective, which provides new insight into plant interactions in agriculture.

Edible flora in pre-Columbian Caribbean coprolites: Expected and unexpected data.

Coprolites, or mummified feces, are valuable sources of information on ancient cultures as they contain ancient DNA (aDNA). In this study, we analyzed ancient plant DNA isolated from coprolites belonging to two pre-Columbian cultures (Huecoid and Saladoid) from Vieques, Puerto Rico, using shotgun metagenomic sequencing to reconstruct diet and lifestyles. We also analyzed DNA sequences of putative phytopathogenic fungi, likely ingested during food consumption, to further support dietary habits. Our findings show that pre-Columbian Caribbean cultures had a diverse diet consisting of maize (Zea mays), sweet potato (Ipomoea batatas), chili peppers (Capsicum annuum), peanuts (Arachis spp.), papaya (Carica papaya), tomato (Solanum lycopersicum) and, very surprisingly cotton (Gossypium barbadense) and tobacco (Nicotiana sylvestris). Modelling of putative phytopathogenic fungi and plant interactions confirmed the potential consumption of these plants as well as edible fungi, particularly Ustilago spp., which suggest the consumption of maize and huitlacoche. These findings suggest that a variety of dietary, medicinal, and hallucinogenic plants likely played an important role in ancient human subsistence and societal customs. We compared our results with coprolites found in Mexico and the United States, as well as present-day faeces from Mexico, Peru, and the United States. The results suggest that the diet of pre-Columbian cultures resembled that of present-day hunter-gatherers, while agriculturalists exhibited a transitional state in dietary lifestyles between the pre-Columbian cultures and larger scale farmers and United States individuals. Our study highlights differences in dietary patterns related to human lifestyles and provides insight into the flora present in the pre-Columbian Caribbean area. Importantly, data from ancient fecal specimens demonstrate the importance of ancient DNA studies to better understand pre-Columbian populations.

Exergy Analysis of a Sugarcane Crop: A Planting-to-Harvest Approach

The objective of this study was to conduct an exergy analysis of sun–plant interactions in sugarcane using mathematical models, aiming to estimate plant production and exergy flows and describe their photosynthetic efficiency during sugarcane cultivation. Sugarcane productivity was determined based on the Brazilian BRCANE model. The efficiency of this crop was evaluated through a simple control volume, where the exergy of solar radiation serves as the sole energy input, and the exergy of the culms and straw represents the useful exergy. The findings revealed an average second-law efficiency of 5% for sugarcane photosynthesis production from solar radiation, with an estimated harvest of approximately 16.29 kWh/m2 of useful extended exergy after a year, and an estimated water consumption of 111.2 m3/ton of harvested stalks. Moreover, this study highlights that exergy efficiency varies significantly in response to seasonal changes. The method developed here can be utilized in future studies to estimate mass and energetic flows and exergy analyses.

Shifts of the soil microbiome composition induced by plant–plant interactions under increasing cover crop densities and diversities

Interspecific and intraspecific competition and facilitation have been a focus of study in plant-plant interactions, but their influence on plant recruitment of soil microbes is unknown. In this greenhouse microcosm experiment, three cover crops (alfalfa, brassica, and fescue) were grown alone, in paired mixtures, and all together under different densities. For all monoculture trials, total pot biomass increased as density increased. Monoculture plantings of brassica were associated with the bacteria Azospirillum spp., fescue with Ensifer adhaerens, and alfalfa with both bacterial taxa. In the polycultures of cover crops, for all plant mixtures, total above-ground alfalfa biomass increased with density, and total above ground brassica biomass remained unchanged. For each plant mixture, differential abundances highlighted bacterial taxa which had not been previously identified in monocultures. For instance, mixtures of all three plants showed an increase in abundance of Planctomyces sp. SH-PL14 and Sandaracinus amylolyticus which were not represented in the monocultures. Facilitation was best supported for the alfalfa-fescue interaction as the total above ground biomass was the highest of any mixture. Additionally, the bulk soil microbiome that correlated with increasing plant densities showed increases in plant growth-promoting rhizobacteria such as Achromobacter xylosoxidans, Stentotrophomonas spp., and Azospirillum sp. In contrast, Agrobacterium tumefaciens, a previously known generalist phytopathogen, also increased with alfalfa-fescue plant densities. This could suggest a strategy by which, after facilitation, a plant neighbor could culture a pathogen that could be more detrimental to the other.

Detection and elimination of insignificant interacting subsystems in MIMO closed-loop systems using the least mean square-based partial correlation algorithm

Closed-loop identification of multi-input multi-output (MIMO) systems in large-scale plants has significant difficulties due to subsystem interactions. This complexity is attributed to several input‒output variables, interactions such as recycling to improve or save material and energy, and disturbances such as heating or cooling within the plant. One of the fundamental problems in closed-loop identification is the input perturbation of the interacting subsystems to capture the dynamics of the system for producing an informative dataset and consequently obtaining an accurate model. However, perturbing all the interacting subsystems in the plant increases the applied excitation signals, which makes the identification a nontrivial task. Thus, a precise and quantitative procedure to evaluate the significance and contribution of such interacting subsystems before applying these excitation signals is required to simplify the identification task. Conventional partial correlation analysis is one of the implemented techniques to measure the significance of these interacting subsystems. However, this technique is based on least square estimation. Thus, incorrect estimation of the model errors is produced due to the correlations amongst the process inputs and unmeasured disturbances. Accordingly, this paper describes the implementation of a developed least mean square-based partial correlation algorithm for detecting and eliminating insignificant interacting subsystems of MIMO closed-loop systems. The developed algorithm can discriminate the interacting subsystems that substantially influence the plant interaction from those that do not by minimizing the model regression errors produced due to the process input correlation, unmeasured disturbances, and colored noise. The effectiveness of the proposed method is demonstrated through a case study.

Temperature-responsive module of OfAP1 and OfLFY regulates floral transition and floral organ identity in Osmanthus fragrans

The MADS-box transcription factor APETELA1 (AP1) is crucially important for reproductive developmental processes. The function of AP1 and the classic LFY-AP1 interaction in woody plants are not widely known. Here, the OfAP1-a gene from the continuously flowering plant Osmanthus fragrans ‘Sijigui’ was characterized, and its roles in regulating flowering time, petal number robustness and floral organ identity were determined using overexpression in Arabidopsis thaliana and Nicotiana tabacum. The expression of OfAP1-a was significantly induced by low ambient temperature and was upregulated with the floral transition process. Ectopic expression OfAP1-a revealed its classic function in flowering and flower ABC models. The expression of OfAP1-a is inhibited by LEAFY (OfLFY) through direct promoter binding, as confirmed by yeast one-hybrid and dual luciferase assays. Arabidopsis plants overexpressing OfAP1-a exhibited accelerated flowering and altered floral organ identities. Moreover, OfAP1-a-overexpressing plants displayed variable petal numbers. Likewise, the overexpression of OfLFY in Arabidopsis and Nicotiana altered petal number robustness and inflorescence architecture, partially by regulating native AP1 in transformed plants. Furthermore, we performed RNA-seq analysis of transgenic Nicotiana plants. DEGs were identified by transcriptome analysis, and we found that the expression of several floral homeotic genes was altered in both OfAP1-a and OfLFY-overexpressing transgenic lines. Our results suggest that OfAP1-a may play important roles during floral transition and development in response to ambient temperature. OfAP1-a functions as a petal number modulator and may directly activate a subset of flowers to regulate floral organ formation. OfAP1-a and OfLFY mutually regulate the expression of each other and coregulate genes that might be involved in these phenotypes related to flowering. The results provide valuable data for understanding the function of the LFY-AP1 module in the reproductive process and shaping floral structures in woody plants.

Systematic thermal analysis of the Arabidopsis proteome: Thermal tolerance, organization, and evolution.

Understanding the thermal stability of the plant proteome in the context of the native cellular environment would aid the design of crops with high thermal tolerance, but only limited such data are available. Here, we applied quantitative mass spectrometry to profile the thermal stability of the Arabidopsis proteome and identify thermo-sensitive and thermo-resilient protein networks in Arabidopsis, providing a basis for understanding heat-induced damage. We also show that the similarities of the protein-melting curves can be used as a proxy to evaluate system-wide protein-protein interactions in non-engineered plants and enable the identification of transient interactions exhibited by metabolons in the context of the cellular environment. Finally, we report a systematic comparison of the thermal stability of paralogs in Arabidopsis to aid the investigation and understanding of gene duplication and protein evolution. Taken together, our results could have broad implications for the fields of plant thermal tolerance, plant protein assemblies, and evolution.

Perspectives of nuclear energy development in Ukraine on the global trends basis

The article examines global trends in the development of the nuclear power industry. It includes the following: extending the operating life of nuclear power units; development of atomic energy in the context of the Paris Agreement; development of nuclear-hydrogen energy; synergistic interaction of renewable energy sources and nuclear power plants; introduction of new reactor technologies. The attitude of different countries of the world to atomic energy is described. It is determined that China and India are the leaders in developing nuclear power. It was determined that small modular reactors are considered transformative reactors that will contribute to the further development of atomic energy in the world. The advantages of small modular reactors in comparison with reactors of large capacity are described, and recommendations for selecting small modular reactors for Ukraine are formulated. Installation of small modular reactors at the operational sites of the NPPs of Ukraine can reduce the financial costs of their construction. Therefore, it will contribute to the sustainable development of the nuclear energy industry of Ukraine.

Plant-Plant Interdependence and Mutualism Interactions in Heterogeneous Ecosystems still hide a lot of secrets

Plant-Plant Interdependence and Mutualism Interactions in Heterogeneous Ecosystems still hide a lot of secrets

A repertoire of candidate effector proteins of the fungus Ceratocystis cacaofunesta

The genus Ceratocystis includes many phytopathogenic fungi that affect different plant species. One of these is Ceratocystis cacaofunesta, which is pathogenic to the cocoa tree and causes Ceratocystis wilt, a lethal disease for the crop. However, little is known about how this pathogen interacts with its host. The knowledge and identification of possible genes encoding effector proteins are essential to understanding this pathosystem. The present work aimed to predict genes that code effector proteins of C. cacaofunesta from a comparative analysis of the genomes of five Ceratocystis species available in databases. We performed a new genome annotation through an in-silico analysis. We analyzed the secretome and effectorome of C. cacaofunesta using the characteristics of the peptides, such as the presence of signal peptide for secretion, absence of transmembrane domain, and richness of cysteine residues. We identified 160 candidate effector proteins in the C. cacaofunesta proteome that could be classified as cytoplasmic (102) or apoplastic (58). Of the total number of candidate effector proteins, 146 were expressed, presenting an average of 206.56 transcripts per million. Our database was created using a robust bioinformatics strategy, followed by manual curation, generating information on pathogenicity-related genes involved in plant interactions, including CAZymes, hydrolases, lyases, and oxidoreductases. Comparing proteins already characterized as effectors in Sordariomycetes species revealed five groups of protein sequences homologous to C. cacaofunesta. These data provide a valuable resource for studying the infection mechanisms of these pathogens in their hosts.

Unveiling novel perspectives on niche differentiation and plasticity in rhizosphere phosphorus forms of submerged macrophytes with different stoichiometric homeostasis

Stoichiometric homeostasis is the ability of organisms to maintain their element composition through various physiological mechanisms, regardless of changes in nutrient availability. Phosphorus (P) is a critical limiting element for eutrophication. Submerged macrophytes with different stoichiometric homeostasis regulated sediment P pollution by nutrient resorption, but whether and how P homeostasis and resorption in submerged macrophytes changed under variable plant community structure was unclear. Increasing evidence suggests that rhizosphere microbes drive niche overlap and differentiation for different P forms to constitute submerged macrophyte community structure. However, a greater understanding of how this occurs is required. This study examined the process underlying the metabolism of different rhizosphere P forms of submerged macrophytes under different cultivation patterns by analyzing physicochemical data, basic plant traits, microbial communities, and transcriptomics. The results indicate that alkaline phosphatase serves as a key factor in revealing the existence of a link between plant traits (path coefficient = 0.335, p < 0.05) and interactions with rhizosphere microbial communities (average path coefficient = 0.362, p < 0.05). Moreover, this study demonstrates that microbial communities further influence the niche plasticity of P by mediating plant root P metabolism genes (path coefficient = 0.354, p < 0.05) and rhizosphere microbial phosphorus storage (average path coefficient = 0.605, p < 0.01). This research not only contributes to a deeper comprehension of stoichiometric homeostasis and nutrient dynamics but also provides valuable insights into potential strategies for managing and restoring submerged macrophyte-dominated ecosystems in the face of changing nutrient conditions.

150 Years of Coevolution Research: Evolution and Ecology of Yucca Moths (Prodoxidae) and Their Hosts.

Yucca moths (Tegeticula and Parategeticula) are specialized pollinators of yucca plants, possessing unique, tentacle-like mouthparts used to actively collect pollen and deposit it onto the flowers of their hosts. The moths' larvae feed on the developing seeds and fruit tissue. First described in 1873, the yucca-yucca moth pollination system is now considered the archetypical example of a coevolved intimate mutualism. Research conducted over the past three decades has transformed our understanding of yucca moth diversity and host plant interactions. We summarize the current understanding of the diversity, ecology, and evolution of this group, review evidence for coevolution of the insects and their hosts, and describe how the nature of the interaction varies across evolutionary time and ecological contexts. Finally, we identify unresolved questions and areas for future research.

Allelopathy and allelobiosis: efficient and economical alternatives in agroecosystems.

Chemical interactions in plants often involve plant allelopathy and allelobiosis. Allelopathy is an ecological phenomenon leading to interference among organisms, while allelobiosis is the transmission of information among organisms. Crop failures and low yields caused by inappropriate management can be related to both allelopathy and allelobiosis. Therefore, research on these two phenomena and the role of chemical substances in both processes will help us to understand and upgrade agroecosystems. In this review, substances involved in allelopathy and allelobiosis in plants are summarized. The influence of environmental factors on the generation and spread of these substances is discussed, and relationships between allelopathy and allelobiosis in interspecific, intraspecific, plant-micro-organism, plant-insect, and mechanisms, are summarized. Furthermore, recent results on allelopathy and allelobiosis in agroecosystem are summarized and will provide a reference for the future application of allelopathy and allelobiosis in agroecosystem.