Fungal Root Research Articles

Changes in the diversity of pecan (Carya illinoinensis) rhizosphere microbial community with different nitrogen fertilization, a case study in Oklahoma pecan orchard

Pecan (Carya illinoinensis) is primarily native to North America and is known as the leading nut produced in Oklahoma. Since the prices of fertilizers have increased and the activity of soil microbes may greatly affect fertilizer utilization, it is important to investigate the effect of fertilization on microbes. Samples were collected from pecan trees receiving full nitrogen (70 lbs/acre), half nitrogen (35 lbs/acre), and no nitrogen (0 lbs/acre) fertilization in an orchard. Microbes were characterized by using the next generation sequencing and annotated into functional groups (trophic mode and nitrogen related) by FUNGuild and FAPROTAX. Our results showed the core fungal genera in this orchard were Tuber and Hymenoscyphus, while the core bacterial families were Chitinophagaceae, Xanthobacteraceae, and Chthoniobacteraceae. Among them, the pecan truffle Tuber lyonii was the dominant fungus. In association with an increase of nitrogen fertilization, the Simpson Index (SI) of fungi in roots was decreased, and the presence of pathotroph (such as Monographella cucumerina and Lectera longa) was increased, implying that the risk of plant infection by pathogens was increased. The pecan with half rate of nitrogen fertilizer had the highest colonization of symbiotrophic fungi, the lowest presence of pathotrophic fungi, and the highest relative abundance of Tuber. The relative abundances of bacteria related to nitrate reduction, nitrogen respiration, and nitrate respiration were found to be the highest in pecan with half rate of nitrogen fertilizer, which might imply the highest efficiency of nitrogen fertilizer utilization in this treatment. It revealed that applying half the recommended nitrogen rate of fertilizer could improve beneficial microbe presence, perhaps increasing nitrogen uptake and decreasing nitrogen needed for optimum production.

Pelatihan Pembuatan Pupuk Hayati pada Sistem Agroforestri berbasis Kopi di Desa Garahan, Jember, Jawa Timur

The productivity of coffee plants on the most cultivated land in Garahan Village decreased. This decline is thought to be caused by, among others, climate change, land degradation and the presence of pests and diseases in coffee plants. This training aims to introduce pests and diseases in coffee-based agroforestry to farmers and develop environmentally friendly biofertilizers. This activity begins with a pre-test, socialization and training and ends post-test. Based on the survey and direct observation, coffee plants found upas fungal diseases, root diseases, and stem borer pests. The agroforestry system applied is complex and straightforward agroforestry. In complex agroforestry, coffee plants are grown with various other crops, such as pepper, vanilla, leucaena, taro, banana, gamal, and mahogany. Simple agroforestry consists of coffee land planted with single-shade crops such as leucaena and gamal or a combination of Leucaena and pine. The training results showed an increased farmer's better understanding of coffee pests and diseases, the benefits of agroforestry, and the manufacture of biofertilizers. The biofertilizer developed is expected to increase the productivity of coffee plants.

Diversity of viruses and viroids in the rhizosphere of common bean cultivars differing in resistance to the fungal root pathogen Fusarium oxysporum

The rhizosphere microbiome plays a key role in plant protection against soil-borne pathogens. Plant breeding for resistance against soil-borne pathogens can alter the rhizosphere microbiome. However, most studies have focused on bacterial and fungal communities, leaving the role of the virus and viroids unassessed. Here, we tested the influence of resistance breeding on the composition of rhizosphere viruses and viroids. By analyzing metatranscriptomes from the rhizosphere of common bean (Phaseolus vulgaris) cultivars with varying resistance to the soil-borne pathogen Fusarium oxysporum, we recovered sequences representing 78 and 23 novel populations of viruses and viroids, respectively. We compared the abundances of these infectious agents across the different cultivars and found that the Fusarium-resistant cultivar harbored >1.2 times more viroids and a more different composition of viroids and viruses than less resistant plants. Given their role in interfering with host metabolism and their potential influence on plant-fungi associations, our study suggests that changes in the rhizosphere infectome are an important consideration in breeding for resistance against soil-borne pathogens.

Drought Eliminates the Difference in Root Trait Plasticity and Mycorrhizal Responsiveness of Two Semiarid Grassland Species with Contrasting Root System.

Root traits and arbuscular mycorrhizal (AM) fungi are important in determining the access of plants to soil resources. However, whether plants with different root systems (i.e., taproot vs. fibrous-root) exhibit different root trait plasticity and mycorrhizal responsiveness under drought remains largely unexplored. Tap-rooted Lespedeza davurica and fibrous-rooted Stipa bungeana were grown in monocultures in sterilized and live soils, followed by a drought treatment. Biomass, root traits, root colonization by AM fungi, and nutrient availability were evaluated. Drought decreased biomass and root diameter but increased the root:shoot ratio (RSR), specific root length (SRL), soil NO3--N, and available P for the two species. Under control and drought conditions, soil sterilization significantly increased the RSR, SRL, and soil NO3--N for L. davurica, but this only occurs under drought condition for S. bungeana. Soil sterilization significantly reduced AM fungal root colonization of both species, but drought significantly increased it in live soil. In water-abundant conditions, tap-rooted L. davurica may depend more on AM fungi than fibrous-rooted S. bungeana; however, under drought conditions, AM fungi are of equal importance in favoring both plant species to forage soil resources. These findings provide new insights for understanding the resource utilization strategies under climate change.

Dodder Parasitism Leads to the Enrichment of Pathogen Alternaria and Flavonoid Metabolites in Soybean Root

Dodders (Cuscuta chinensis) are rootless and holoparasitic herbs that can infect a variety of host plants, including the vitally important economic and bioenergy crop soybean (Glycine max). Although dodder parasitism severely affects the physiology of host plants, little is known about its effects on fungal communities and root secondary metabolites in hosts. In this study, variations in root-associated fungal communities and root metabolites of soybean under different parasitism conditions were investigated using ITS rRNA gene sequencing and UPLC–MS/MS metabolome detection technologies. The results showed that dodder parasitism significantly altered the composition and diversity of the fungal communities in the rhizosphere and endosphere of soybean. The relative abundance of the potential pathogenic fungus Alternaria significantly increased in the root endosphere of dodder-parasitized soybean. Furthermore, correlation analysis indicated that the fungal community in the root endosphere was susceptible to soil factors under dodder parasitism. Meanwhile, the content of soil total nitrogen was significantly and positively correlated with the relative abundance of Alternaria in the rhizosphere and endosphere of soybean. Metabolomic analysis indicated that dodder parasitism altered the accumulation of flavonoids in soybean roots, with significant upregulation of the contents of kaempferol and its downstream derivatives under different parasitism conditions. Taken together, this study highlighted the important role of dodder parasitism in shaping the fungal communities and secondary metabolites associated with soybean roots, providing new insights into the mechanisms of multiple interactions among dodder, soybean, microbial communities and the soil environment.

Fragment size and diversity of mulches affect their decomposition, nutrient dynamics, and mycorrhizal root colonisation

Plant-based mulch has been proposed as a sustainable way of maintaining soil fertility. However, the role of mulch diversity, quality, and size in decomposition dynamics, and their effect on crop yield, has not been fully explored. We investigated how mulch quality, proxied by the constituent plant species diversity, and residue size drive mulch decomposition, nutrient release, crop nutrition, and yield. A rhizotron experiment was set up with barley as a model crop, with the addition of mulch of two particle sizes (1.5 and 30 cm) and four different plant residue mixes of differing biodiversity (17, 12, 6, and 1 species) in a fully factorial design. Soil nutrient dynamics were measured at advanced decomposition stages, together with residue quality, arbuscular mycorrhizal fungal (AMF) root colonisation, and crop yield. Residue mass loss was significantly affected by its chemical composition. Initial NDF content was more restricted factor in C and N mineralisation than C:N or lignin. Long residues retained significantly higher C and N content, than short residues. Crop yield was not affected by residue type or size. Residue size significantly affected barley growth rate, influencing seed protein content. Soil available K was significantly increased by residues with a higher initial C:N ratio. Short residues resulted in higher soil Zn. Residues of higher diversity resulted inhigher AMF root colonisationof the barley plants. Generally, long residue mulches maintain higher fertilisation capacity at advanced stage of decomposition than short ones, without a deleterious effect on crop yield. Further investigation should evaluate the effect of continuous application of long residue mulches on soil fertility and microbial symbiosis.

Woodland wildfire enables fungal colonization of encroaching Douglas‐fir

Abstract Self‐reinforcing differences in fire frequency help closed‐canopy forests, which resist fire, and open woodlands, which naturally burn often, to co‐occur stably at landscape scales. Forest tree seedlings, which could otherwise encroach and overgrow woodlands, are killed by regular fire, yet fire has other effects that may also influence these feedbacks. In particular, many forest trees require symbiotic ectomycorrhizal fungi in order to establish. By restructuring soil fungal communities, fire might affect the availability of symbionts or the potential for symbiont sharing between encroaching trees and woodland vegetation. To investigate this possibility, we performed a soil bioassay experiment using inoculum from burned and unburned oak woodlands and Douglas‐fir forests. We examined how fire, ecosystem type, and neighboring heterospecific seedlings affect fungal root community assembly of Douglas‐firs and oaks. We asked whether heterospecific seedlings facilitated fungal colonization of seedling roots in non‐native soil, and if so, whether fire influenced this interaction. External fungal colonization of oak roots was more influenced by fire and ecosystem type than by the presence of a Douglas‐fir, and oaks increased the likelihood that Douglas‐fir roots would be colonized by fungi in oak woodland soil. Yet, fire increased colonization of Douglas‐fir in oak soil, diminishing the otherwise crucial role played by oak facilitation. Fire also strengthened the positive effect of Douglas‐firs on oak root‐associated fungal diversity in Douglas‐fir forest soil. Prior work shows that fire supports woodland ecosystems by stemming recruitment of encroaching seedlings. Here, we find evidence that it may contrastingly reduce fungal limitation of invasive seedling growth and establishment, otherwise relieved only by facilitation. Future work can investigate how these opposing effects might contribute to the net impact of changes in fire regime on landcover stability. Read the free Plain Language Summary for this article on the Journal blog.

From the wild to the field: effect of foliar or soil application of inorganic or semi-organic fertilizers on various parameters of four local endemic plant species of Crete (Greece)

Domestication of wild plant species of interest coupled with introduction of pilot cultivation practices and appropriate fertilization schemes could be an efficient alternative for addressing sustainable exploitation needs of threatened and/or declining wild phytogenetic resources. In this field study focusing on four threatened wild-growing plants (Carlina diae, Origanum dictamnus, Origanum microphyllum, and Sideritis syriaca subsp. syriaca) confined to Crete (local endemics), the effects of three types of fertilization (inorganic, plain semi-organic or co-applied with commercial biostimulants based on edible raw plant materials) by two methods (foliar/soil application) on plants’ growth were investigated. Specifically, plant parameters such as aboveground biomass yield, content and uptake of nutrients by plants as well as arbuscular mycorrhizal fungi root colonization were evaluated. Results revealed a distinction in plants’ multi-elemental stoichiometry, except in the case of Origanum species, in which the variance of their ionomics showed a significant overlap. The elements most closely related to yield were K and Zn, while Pearson tests showed various correlations between studied essential nutrients. Among them, the positive correlations between B and Ca, and Mg (with r value up to 0.9 at p ≤ 0.001, in all studied species except O. dictamnus); the negative correlations between K and Mg (in O. dictamnus and S. syriaca subsp. Syriaca, r = − 0.5 at p ≤ 0.001); and the positive correlation patterns between Fe and Mn, or Cu and Zn, respectively (in all studied species) , were observed. Biostimulant application alone or in combination with semi-organic fertilizers increased the yield of C. diae (up to 161%) and of the two Origanum species studied (up to 70% and 68% for O. dictamnus and for O. microphyllum, respectively), while inorganic fertilization was beneficial for S. syriaca subsp. syriaca (up to 170% increase) and O. microphyllum (up to 79% increase). However, no solid conclusions could be derived in respect of the preference of the four species for any fertilizers' application method (foliar or by soil).

Plant disease management with amelioration of systemic resistance in soybean by endophytic fungi associated with GC-MS metabolic profiling of Chaetomium sp.,

Plants exhibit beneficial associations between fungal endophytes and roots for better growth, disease suppression, and stress tolerance. Considerable information is now available about the beneficial role of fungal endophytes. In this study, endophytic fungi Chaetomium sp., Curvularia chonburiensis, C. specifera, C. hawaiiensis, Rhizoctonia solani, Fusarium solani, Talaromyces assiutensis and T. trachyspermus isolated and evaluated for nematocidal activity against a root-knot nematode Meloidogyne javanica. The culture filtrates of endophytic fungi were prepared and used to check their efficacy against root knot nematodes. The culture filtrates of endophytic fungi were applied to pot and field experiments using soybean as host plants. In vitro study of these endophytic fungal culture filtrates showed strong nematocidal activity by killing juveniles of M. javanica to a certain degree, while Chaetomium sp., and Talaromyces assiutensis showed 100% mortality rate after 48 h. The application of Cephalosporium sp., Chaetomium sp., Talaromyces trachyspermus and T. assiutensis suppressed root rotting fungi of soybean in both screen house and field plots experiments. Significance of fungal isolates was further confirmed by repeated experiments. Endophytic fungi also showed positive impacts on the host plants by increasing the rate of their growth and improving their tolerance level to biotic stress which was evident by the production of increased amounts of resistance markers like salicylic acid and polyphenol contents with subsequent improvement of the antioxidant status. The n-hexane fraction of the culture filtrate of Chaetomium sp., were subjected to GC-MS analysis for the identification of compounds and some new compounds have been reported for the first time from this fungus. The results will facilitate a better understanding of host plant and fungal interaction and are likely to assist in the screening and utilization of beneficial microbes.

The impact of ice storms on mycorrhizal fungi varies by season and mycorrhizal type in a hardwood forest

AbstractExtreme weather events, such as ice storms, are increasing and have potentially large impacts on forests, including belowground structures such as fine roots and mycorrhizal fungi. Many forest trees rely on the mutualistic relationship between mycorrhizal fungi and plants; a relationship that, when disrupted, can negatively impact tree net primary productivity. We took advantage of a large‐scale ice storm manipulation in the northeastern United States to test the hypothesis that increasing ice storm intensity and frequency would reduce ectomycorrhizal fungal root tips per unit root length and arbuscular mycorrhizal fungal structures per unit root length, hereafter colonization. We found that ice storm intensity reduced spring ectomycorrhizal fungal and arbuscular mycorrhizal fungal colonization. However, these patterns changed in the fall, where ice storm intensity still reduced ectomycorrhizal fungal root tips, but arbuscular mycorrhizal fungal colonization was higher in ice storm treatments than controls. The amount of ectomycorrhizal fungal root tips and arbuscular mycorrhizal fungal colonization differed seasonally: ectomycorrhizal fungal root tips were 1.7× higher in the spring than in the fall, while arbuscular mycorrhizal fungal colonization was 3× higher in the fall than in the spring. Our results indicate that mycorrhizal fungal colonization responses to ice storm severity vary temporally and by mycorrhizal fungal type. Further, arbuscular mycorrhizal fungi may recover from ice storms relatively quickly, potentially aiding forests in their recovery, whereas ice storms may have a long lasting impact on ectomycorrhizal fungi.

Drought neutralizes positive effects of long‐term grazing on grassland productivity through altering plant–soil interactions

Abstract Livestock grazing is among the most intensive land‐use activities in grasslands, and can affect plant communities directly or indirectly via grazing‐induced soil legacies. Under climate change, grasslands are threatened globally by recurrent drought. However, the extent to which drought influences grazing‐induced soil legacy effects on plant biomass production and community composition remains largely unexplored. We grew five naturally co‐occurring plant species (three dominants and two subordinates) in mixed communities in a glasshouse experiment in live and sterilized soil that had or had not been subjected to 19 years of grazing; these plant communities were then exposed to a subsequent drought. We tested the treatment effects on plant community biomass, proportional above‐ground biomass of individual species, arbuscular mycorrhizal (AM) fungal root colonization, and soil nutrient availability. Under drought‐free conditions, soils from grazed plots produced significantly higher plant above‐ground and total community biomass compared to soils from ungrazed plots. In contrast, plant above‐ground and total community biomass were similar between grazed and ungrazed soils under drought conditions. Similarly, soils from grazed plots increased the proportional biomass of dominant species but decreased the proportion of subordinate species; however, the proportional biomass of dominant and subordinate species was similar between grazed and ungrazed soils under drought conditions. Soil NO3−‐N in grazed soil was significantly higher compared to ungrazed soil. Drought dramatically increased soil NO3−‐N in sterilized soil and had a more pronounced increase in grazed soil than in ungrazed soil. Arbuscular mycorrhizal fungal root colonization from grazed soil was lower compared to ungrazed soil. Drought significantly increased the soil available phosphorus concentration, as well as plant community AM fungal root colonization. Synthesis. Our study suggests that drought can neutralize positive grazing effects on plant community biomass production via altered plant–soil interactions. Also, we found that drought can alleviate the negative effects of grazing legacies on subordinate species by reducing competitiveness of dominant species. Our study provides new insights for understanding the underlying mechanisms of grazing effects on grassland productivity under climate change. Read the free Plain Language Summary for this article on the Journal blog.

Role of carbohydrate-active enzymes in mycorrhizal symbioses.

Mycorrhizal fungi form mutually beneficial interactions with a wide range of terrestrial plants. During this symbiosis, the associated fungus provides mineral nutrients, such as phosphorus and nitrogen, to its host plant in exchange of photosynthesis-derived carbohydrates. Genome sequencing of mycorrhizal fungi has shown that arbuscular mycorrhizal fungi and ectomycorrhizal fungi have a restricted set of plant-cell wall degrading enzymes (PCWDE) genes, while orchid and ericoid mycorrhizal fungi have an extended PCWDE repertoire similar to soil decomposers and wood-decay fungi. On the other hand, mycorrhizal fungi have retained a substantial set of carbohydrate active enzymes (CAZymes) acting on microbial polysaccharides. Functional analysis has shown that several of the remaining PCWDEs are involved in the fungal root colonization and establishment of the symbiotic interface. In this review, we highlight the current knowledge on the evolution and function of PCWDEs in mycorrhizal fungi.

Impacts of Rock Mineral and Traditional Phosphate Fertilizers on Mycorrhizal Communities in Pasture Plants.

Intensive fertilizer use can constrain contributions from soil biological processes in pastures, including those associated with arbuscular mycorrhizal (AM) fungi. We evaluated the effect of fertilizers of different P solubility on the colonization of the roots of two common pasture plants by a community of AM fungi in a pasture soil. The treatments were a rock mineral fertilizer, a chemical fertilizer and a microbial inoculant. Subterranean clover and annual ryegrass were grown in pots for 10 weeks. Both fertilizers reduced the proportion and length of roots colonized by naturally occurring AM fungi. However, by 10 weeks, there was a much greater length of mycorrhizal root for annual ryegrass than for subterranean clover. The relative abundance of mycorrhizal fungi in the families Glomeraceae and Acaulosporaceae in roots was not affected by the form of fertilizer, but diversity indices of AM fungi in roots were altered. The chemical fertilizer had a greater negative effect on AM fungal diversity indices in the annual ryegrass roots compared with the subterranean clover roots. The reduction in OTU richness of AM fungi with fertilizer application corresponded with reduced soil pH. Differential effects of P fertilizers on naturally occurring AM fungi in this agricultural soil have the potential to influence the efficacy of P fertilizer use and dominance of plant species in grasslands.

Antifungal activity and optimization procedure of silver nanoparticles green synthesized with Prunus laurocerasus L. (cherry laurel) leaf extract

In the present study, Box-Behnken design (BBD) was applied to optimize the green synthesis conditions of silver nanoparticles (AgNPs) using Prunus laurocerasus (cherry laurel) leaf extract as a reducing and stabilizing agent. Three important synthesis factors such as the concentration (mM) of silver nitrate (AgNO3), pH of cherry laurel leaf extract and reaction temperature (°C) were used as independent variables of the model, and the absorbance intensity originating from AgNPs was employed as a dependent variable. Statistical analyzes showed that the optimized conditions for the predicted absorbance at 405 nm (2.35 A.U) were determined at a concentration of 10 mM AgNO3, a pH of 9.0, and a temperature of 50°C. The validity of the developed model was verified, and the average absorbance from six experimental runs was recorded as 2.26 (A.U) with an error of 14.86%. In addition, the synthesized AgNPs were characterized using ultraviolet (UV)–visible (Vis) spectroscopy, fourier transform infrared (FT–IR) spectroscopy, and scanning electron microscope (SEM)-energy dispersive X-ray spectroscopy (EDS) was used to examine the morphology and average size of AgNPs. The synthesized AgNPs also showed antifungal activities against all five fungal kiwifruit pathogens tested in vitro. The LC50 values of the synthesized AgNPs were 10.88, 9.30, 7.15, 25.16 and 53.77 µg/ml for Phytopythium vexans, Globisoprangium sylvaticum, G. intermedium, Phytophthora citrophthora and Rhizoctonia solani, respectively. Except for the MIC values of Globisporangium species (120 µg/ml), both MIC and MFC values of the other three species were found to be above 150 µg/ml. The results of this study indicate that AgNPs synthesized using cherry laurel leaf extract should be further investigated for use in the control of fungal root and stem rot diseases in kiwifruit.

Climate-driven shifts in plant and fungal communities can lead to topsoil carbon loss in alpine ecosystems.

Alpine tundra ecosystems suffer from ongoing warming-induced tree encroachment and vegetation shifts. While the effects of tree line expansion on the alpine ecosystem receive a lot of attention, there is also an urgent need for understanding the effect of climate change on shifts within alpine vegetation itself, and how these shifts will consequently affect soil microorganisms and related ecosystem characteristics such as carbon storage. For this purpose, we explored relationships between climate, soil chemistry, vegetation, and fungal communities across seven mountain ranges at 16 alpine tundra locations in Europe. Among environmental factors, our data highlighted that plant community composition had the most important influence on variation in fungal community composition when considered in combination with other factors, while climatic factors had the most important influence solely. According to our results, we suggest that rising temperature, associated with a replacement of ericoid-dominated alpine vegetation by non-mycorrhizal or arbuscular mycorrhizal herbs and grasses, will induce profound changes in fungal communities toward higher dominance of saprotrophic and arbuscular mycorrhizal fungi at the expense of fungal root endophytes. Consequently, topsoil fungal biomass and carbon content will decrease.

Linking fungal community structure with soil nitrogen dynamics following forest conversion in a subalpine forest in China

The conversion of natural forests to plantations affects soil carbon (C) and nitrogen (N) dynamics. However, the underlying microbial mechanisms of C and N dynamics caused by forest conversion, particularly the functional role of ectomycorrhizal (ECM) fungi, remain largely unknown. Here, we investigated the soil and root-associated fungal communities, soil and ECM root enzyme activities, and C and N mineralization rates in natural forests and plantations in the western Sichuan subalpine coniferous forest. Soil fungal and root ECM fungal communities were determined by high-throughput and Sanger sequencing, respectively. ECM root surface enzymes were used to assess fungal function, while soil enzymes, C and N mineralization, were used to evaluate soil function.Our results showed that clearing natural forests and converting them to plantations led to lower soil organic carbon (SOC), total nitrogen (TN), and pH, which drove changes in ECM and saprophytic (SAP) fungal communities. After forest conversion, the main difference in the fungal community was an increase in the ratio of ECM to SAP fungi. The most apparent change in the soil ECM fungal community is the shift of the dominant genera from Russula to Cortinarius and Piloderma. Subsequently, the function of the ECM fungal community was altered. The results indicated that the conversion of the natural forest to the plantation reduced ECM community β-glucosidase (βG), β-glucuronidase (βLU), N-acetyl-β-D-glucosaminidase (NAG), and acid phosphatase (AP) activities, and soil βG, NAG, and leucine aminopeptidase (LAP) activities. Among them, the activities of βG, βLU, and NAG in the ECM fungal community were significantly correlated with the activities of βG, βLU, and NAG in soil, respectively. Finally, we show that converting natural forests to plantations significantly increased the ammonification rate while decreasing the nitrification and mineralization rates. The close relationship between the relative abundance and diversity of the ECM fungal community, ECM communities and soil NAG, and N processes indicated that the changes in soil N dynamic after forest conversion were directly related to the changes in the ECM fungal community. Our results provide insight into soil C and N dynamics mechanisms resulting from forest conversion.

Drivers of bacterial and fungal root endophyte communities: understanding the relative influence of host plant, environment, and space

Bacterial and fungal root endophytes can impact the fitness of their host plants, but the relative importance of drivers for root endophyte communities is not well known. Host plant species, the composition and density of the surrounding plants, space, and abiotic drivers could significantly affect bacterial and fungal root endophyte communities. We investigated their influence in endophyte communities of alpine plants across a harsh high mountain landscape using high-throughput sequencing. There was less compositional overlap between fungal than bacterial root endophyte communities, with four 'cosmopolitan' bacterial OTUs found in every root sampled, but no fungal OTUs found across all samples. We found that host plant species, which included nine species from three families, explained the greatest variation in root endophyte composition for both bacterial and fungal communities. We detected similar levels of variation explained by plant neighborhood, space, and abiotic drivers on both communities, but the plant neighborhood explained less variation in fungal endophytes than expected. Overall, these findings suggest a more cosmopolitan distribution of bacterial OTUs compared to fungal OTUs, a structuring role of the plant host species for both communities, and largely similar effects of the plant neighborhood, abiotic drivers, and space on both communities.

Community structure of endophytic fungi in roots and leaves of Fagopyrum mill and Avena sativa in a Chinese northern cold region

In order to explore the endophytic fungi of Fagopyrum Mill and Avena sativa, Illumina Miseq high-throughput sequencing was used to analyze the community structure and diversity of endophytic fungi in leaves and roots of buckwheat and oat at the mature stage. The results of community structure showed that there were 205 operational taxonomic units (OTUs) in buckwheat roots and 181 OTUs in buckwheat leaves based on 97% sequence similarity level. There were 152 OTUs and 127 OTUs in the root and the leaf of oat, respectively. At the phylum level, Ascomycota and Basidiomycota were the dominant endophytic fungi in buckwheat roots and leaves, while Ascomycota was the dominant endophytic fungus in oat roots and leaves. Alpha diversity analysis showed that the Ace index, Chao index and Shannon index of buckwheat roots were higher than that of buckwheat leaves, and the three indices of oat roots were also higher than that of oat leaves, indicating that the richness and diversity of endophytic fungi community in roots were higher than that in leaves. Biomarkers were found by significant difference analysis in buckwheat and oat. The endophytic functional groups of buckwheat and oat were mainly distributed in Pathotroph and Saprotroph. The results of this study laid a foundation for fully exploiting the dominant endophytic fungal resources of buckwheat and oat and further developing microbial fertilizers.

Fungal Root Rots of Sugar Beets: A Review of Common Causal Agents and Management Strategies

Fungal Root Rots of Sugar Beets: A Review of Common Causal Agents and Management Strategies

PHYTOPATHOLOGICAL MONITORING OF DANGEROUS OUTBREAKS DISEASE OF FOREST TREES WITH USE METHOD OF CHANGING RADIAL INCREMENTS IN THE CONDITIONS OF THE POLISKY NATURE RESERVE

PHYTOPATHOLOGICAL MONITORING OF DANGEROUS OUTBREAKS DISEASE OF FOREST TREES WITH USE METHOD OF CHANGING RADIAL INCREMENTS IN THE CONDITIONS OF THE POLISKY NATURE RESERVE