scholarly journals Endophytic fungi facilitate the coexistence of host grasses and neighboring legumes by changing rhizobial abundance

2021 ◽  
Author(s):  
Xiaowen Fan ◽  
Yongkang Deng ◽  
Xiaoyu Ge ◽  
Ke Dong ◽  
Lei Chen ◽  
...  
Keyword(s):  
Sinorhizobium Meliloti ◽  
Species Coexistence ◽  
Biomass Accumulation ◽  
Plant Leaves ◽  
Promoting Effect ◽  
Mesorhizobium Ciceri ◽  
Grass Endophyte ◽  
Natural Grasslands ◽  
Endophyte Infection ◽  
Epichloë Endophytes

Abstract Purpose: Grass-endophyte and legume-rhizobium symbionts coexist in grasslands. However, the effects of endophyte infection on legume-rhizobium symbionts remain poorly understood, especially in natural grasslands. Methods: In this study, Achnatherum sibiricum - Epichloë endophytes and Medicago ruthenica -rhizobia were selected as materials to investigate whether and how endophyte infection affected the growth of legume-rhizobia symbionts. It was hypothesized that endophytes can facilitate the coexistence of grass-legume systems. Results: The results demonstrated that endophyte infection affected the growth of both rhizobia and M. ruthenica -rhizobia symbionts, and the results depended on rhizobial identity. Endophyte infection inhibited the growth of Mesorhizobium ciceri , which significantly promoted the growth of M. ruthenica , and promoted Sinorhizobium meliloti , which had no significant effect on the growth of M. ruthenica . Endophyte infection also changed the interaction between A. sibiricum and M. ruthenica . When inoculated with M. ciceri , endophyte infection weakened the promoting effect of A. sibiricum on M. ruthenica , while when inoculated with S. meliloti , endophyte infection enhanced the promoting effect. Endophyte infection affected the growth of M. ruthenica -rhizobia symbionts by affecting rhizobia abundance in roots and nitrogen content in plant leaves. Conclusion: In conclusion, endophyte infection was beneficial to biomass accumulation and species coexistence in grass-legume mixed planting systems. In this study, it was proposed that endophyte infection may change the growth of legume-rhizobia symbionts by affecting the growth and nitrogen fixation of rhizobia.

Transformation of Sinorhizobium meliloti MTCC 100 and Mesorhizobium ciceri TAL 620 by CaCl2 method

2010 ◽  
Vol 56 (1) ◽  
pp. 74-76 ◽  
Author(s):  
Urmi Patel ◽  
Sarika Sinha
Keyword(s):  
Escherichia Coli ◽  
Optical Density ◽  
Sinorhizobium Meliloti ◽  
Transformation Efficiency ◽  
Binary Vector ◽  
Transformation Method ◽  
Mesorhizobium Ciceri ◽  
Competent Cells

The CaCl2 method, commonly used for transformation of Escherichia coli, was modified and used to develop a simpler and easier transformation method for Rhizobia sp. Two species of Rhizobia, Sinorhizobium meliloti MTCC 100 and Mesorhizobium ciceri TAL 620, were transformed with the 13.2 kb binary vector pGA482. At an optical density of 0.4, the transformation efficiencies in Sinorhizobium meliloti MTCC 100 and Mesorhizobium ciceri TAL 620 were 104 and 103, respectively. Competent cells of Sinorhizobium meliloti MTCC 100 were prepared at different growth intervals and transformed by the same vector. A maximum transformation efficiency of 104 was achieved at an optical density of 0.5.

Fungal endophytes of Festuca rubra increase in frequency following long-term exclusion of rabbits

Botany ◽  
2015 ◽  
Vol 93 (4) ◽  
pp. 233-241 ◽  
Author(s):  
James S. Santangelo ◽  
Nash E. Turley ◽  
Marc T.J. Johnson
Keyword(s):  
Plant Growth ◽  
Intraspecific Competition ◽  
Fungal Endophytes ◽  
Natural Populations ◽  
Fungal Endophyte ◽  
Festuca Rubra ◽  
Red Fescue ◽  
Grass Endophyte ◽  
Defensive Mutualism ◽  
Endophyte Infection

Plant – fungal endophyte interactions are common in nature and they can shape the ecology of plants. Vertically transmitted endophytes are hypothesized to serve as mutualists, protecting plants from herbivores. If this hypothesis is true, then we expect endophytes to be most abundant in the presence of herbivores and least abundant in their absence, assuming endophytes incur a cost to their host. We tested this prediction by studying the effects of intense rabbit (Oryctolagus cuniculus Linnaeus) grazing on grass–endophyte interactions at Silwood Park, UK. We examined seeds of red fescue (Festuca rubra L.) collected from 15 natural populations that were protected from rabbits for 0.3–21 years. Contrary to our prediction, the mean proportion of seeds with endophytes increased 1.84×, from 0.45 to 0.83, following 21 years of rabbit exclusion. To better understand the mechanisms driving this increase in frequency, we conducted a fully factorial greenhouse experiment where we manipulated the presence or absence of endophyte infection, intraspecific competition, and simulated grazing on F. rubra plants. In both damaged and undamaged treatments, infected plants produced approximately twice as much biomass as uninfected plants, and endophytes did not influence tolerance to herbivory. These results suggest that endophytes directly change plant growth but not compensatory responses to damage. In the absence of competitors, infected plants produced 2.17× more biomass than uninfected plants, whereas in the presence of competitors, infected plants produced only 1.55× more biomass than uninfected plants. This difference suggests that intraspecific competition might lessen the benefits of endophyte infection. Our results do not support the defensive mutualism hypothesis, but instead suggest that endophyte-induced plant growth is important in shaping the costs and benefits of endophytes in our system.

Soybean PI 675847 A as a new source of salt tolerance

2018 ◽  
Vol 17 (1) ◽  
pp. 33-44 ◽  
Author(s):  
Truyen Ngoc Quach ◽  
Lan-Anh Thi Nguyen ◽  
Nga Thi Nguyen ◽  
Cuc Thi Nguyen ◽  
Thang Quang Dam ◽  
...  
Keyword(s):  
Salt Tolerance ◽  
Biomass Accumulation ◽  
Nacl Stress ◽  
Plant Leaves ◽  
Cell Membrane Stability ◽  
Ion Contents ◽  
Improvement Programs ◽  
Genetic Source ◽  
Salt Affected Soils ◽  
Legume Production

AbstractSoil salinity is a major limitation to legume production in many areas of the world. Identification of the genetic source of salt tolerance is critical in soybean breeding for improving soybean production in salt-affected regions. Vietnam has unique sources of soybean germplasm and varieties are grown in the area where exposure to salinity is frequent. However, there is little research on the identification of salt tolerant sources in the Vietnamese gene pool. The present study compared 18 Vietnamese soybean cultivars for their differences in salt tolerance. Under a range of NaCl stress from 0 to 200 mM NaCl, there was a large variation in salt tolerance among the 18 soybean lines evaluated. The soybean accession PI 675847 A (Vietnamese variety DT2008), was identified as a useful source of salt tolerance. During vegetative growth, PI 675847 A had lower leaf scorch scores, higher cell membrane stability, better photosynthesis and biomass accumulation under NaCl stress than the other 17 strains evaluated. In addition, PI 675847 A maintained better growth and seed yield in salt-affected soils compared with the sensitive lines. Analyses of ion contents in plant leaves under saline conditions showed that PI 675847 A was able to limit uptake and transport of Na+ and Cl−. Because of its higher productivity under saline conditions, PI 675847 A will be a useful germplasm source in soybean improvement programs for salt tolerance.

scholarly journals neotyphodium spp.- grass association in natural grassland in Argentina

2007 ◽  
Vol 13 ◽  
pp. 95-99
Author(s):  
M.N. Colabelli ◽  
M.S. Torres ◽  
A.M. Clausen ◽  
O.N. Fernandez ◽  
A. Peretti
Keyword(s):  
Festuca Arundinacea ◽  
Lolium Multiflorum ◽  
Fungal Endophytes ◽  
Economic Losses ◽  
Germplasm Collections ◽  
Grass Endophyte ◽  
Natural Grasslands ◽  
Potential Benefits ◽  
Natural Grassland ◽  
Livestock Diseases

The agronomic importance of the grass-endophyte association became apparent after it was linked to livestock diseases. This paper reports the incidence of endophytes in natural grasslands in Argentina from data collected through grass seed collections, tillers and culms from natural grasslands. A total of 159 samples were analysed: 144 grass collections from 30 species were obtained from accessions (germplasm bank of EEA Balcarce- INTA), and 15 samples were collected in the field in the province of Buenos Aires (Balcarce and Ayacucho). The samples were analysed according to Saha et al. (1988) or Belanger (1996). Endophytes were found in only nine of the 30 species of accessions analysed; accessions of Lolium multiflorum showed the highest incidence of endophyte infection, ranging from 57 to 100%. Of the 15 field populations collected: Festuca arundinacea and L. multiflorum samples were infected with infection ranging from 89 to 100%; populations of Bothriochloa, Deyeuxia, Piptochaetium, Sporobolus, Stipa megapotamia, S. papposa, were endophyte free. The economic losses to the livestock industry and the potential benefits of endophytes as biological agents to improve plant fitness and pest resistance of forage grasses increases the importance of determining the incidence of fungal endophytes in grass germplasm collections and natural grasslands. Keywords: native grasses, endophytes, naturalised grasses, Argentina

scholarly journals First Report of Choke Disease Caused by Epichloë baconii in the Grass Agrostis castellana

Plant Disease ◽  
2003 ◽  
Vol 87 (3) ◽  
pp. 314-314
Author(s):  
M. Romo Vaquero ◽  
B. R. Vázquez de Aldana ◽  
A. García Ciudad ◽  
B. García Criado ◽  
I. Zabalgogeazcoa
Keyword(s):  
Flag Leaf ◽  
Infected Plant ◽  
Its2 Region ◽  
Diseased Plant ◽  
Fungal Culture ◽  
Plant Host ◽  
Grass Endophyte ◽  
Natural Grasslands ◽  
Agrostis Castellana ◽  
Choke Disease

Agrostis castellana is common in semiarid natural grasslands of the province of Salamanca, Spain. In this area, plants showing fungal stromata in their stems were observed in July of 2001. These symptoms are typical of choke disease, caused by Epichloë species in several grasses (3). In this disease, external fungal stromata develop around the leaf sheath of the flag leaf during the reproductive cycle of the plant host. As a result, the inflorescence does not emerge. In natural populations of A. castellana, less than 1% of plants showed disease symptoms, and all the stems of infected plants were sterilized by stromata. Intercellular endophytic mycelium was observed by microscopy in stem pith of diseased plants, but not on samples of 30 apparently healthy plants (1). Ergovaline, a fungal alkaloid, was not detected in lyophilized samples of infected plant tissue (2). In a fungal culture obtained from surface-disinfected leaf sheaths of a diseased plant (1), reniform conidia and conidiophores characteristic of the genus Epichloë were observed (4). To determine the fungal species, the nucleotide sequence of the ITS1-5.8SrRNA-ITS2 region and the three first introns of the beta-tubulin gene were obtained (EMBL Accession Nos. AJ490938 and AJ490939). When compared to those of other Epichloë species, these sequences identified the fungus from A. castellana as E. baconii (3). This fungus has been previously described as a pathogenic fungal endophyte in other Agrostis and Calamagrostis species (3,4). The fact that all stems of infected plants were diseased, infection incidence was low, and no alkaloids were detected in plants suggests that this grass-endophyte interaction is pathogenic and not mixed or mutualistic. References: (1) E. Clark et al. J. Microbiol. Methods 1:149, 1983. (2) N. Hill et al. Crop Sci. 33:331, 1993. (3) A. Leuchtmann et al. Mycol. Res. 102:1169, 1998. (4) J. White Jr. Mycologia 85:444, 1993

scholarly journals Capability of the Invasive Tree Prosopis glandulosa Torr. to Remediate Soil Treated with Sewage Sludge

2019 ◽  
Vol 11 (9) ◽  
pp. 2711 ◽  
Author(s):  
Ahmed Mahmoud Abbas ◽  
Sameh K. Abd-Elmabod ◽  
Soad M. El-Ashry ◽  
Wagdi Saber Soliman ◽  
Noha El-Tayeh ◽  
...  
Keyword(s):  
Sewage Sludge ◽  
Plant Traits ◽  
Biomass Accumulation ◽  
Prosopis Glandulosa ◽  
Arid Environments ◽  
Plant Leaves ◽  
Ground Biomass ◽  
High Metal ◽  
Invasive Tree ◽  
Below Ground

Sewage sludge improves agricultural soil and plant growth, but there are hazards associated with its use, including high metal(loid) contents. An experimental study was conducted under greenhouse conditions to examine the effects of sewage sludge on growth of the invasive tree Prosopis glandulosa, as well as to determine its phytoremediation capacity. Plants were established and grown for seven months along a gradient of sewage sludge content. Plant traits, soil properties, and plant and soil concentrations of N, P, K, Cd, Pb, Cu, Ni, Zn, Cr, Co, As, and Fe were recorded. The addition of sewage sludge led to a significant decrease in soil pH, and Ni, Co, and As concentrations, as well as an increase in soil organic matter and the concentrations of N, P, Cu, Zn, and Cr. Increasing sewage sludge content in the growth medium raised the total uptake of most metals by P. glandulosa plants due to higher biomass accumulation (taller plants with more leaves) and higher metal concentrations in the plant tissues. P. glandulosa concentrated more Cd, Pb, Cu, Zn, and Fe in its below-ground biomass (BGB) than in its above-ground biomass (AGB). P. glandulosa concentrated Ni, Co, and As in both BGB and AGB. P. glandulosa has potential as a biotool for the phytoremediation of sewage sludges and sewage-amended soils in arid and semi-arid environments, with a potential accumulation capability for As in plant leaves.

Novel grass–endophyte associations reduce the feeding behaviour of invasive European rabbits (Oryctolagus cuniculus)

2016 ◽  
Vol 43 (8) ◽  
pp. 681 ◽  
Author(s):  
Christopher G. L. Pennell ◽  
M. Philip Rolston ◽  
A. David M. Latham ◽  
Wade J. Mace ◽  
Ben Vlaming ◽  
...  
Keyword(s):  
Festuca Arundinacea ◽  
Feeding Behaviour ◽  
Oryctolagus Cuniculus ◽  
Management Tools ◽  
Grass Endophyte ◽  
European Rabbits ◽  
Domestic Rabbits ◽  
Bird Management ◽  
Pellet Feed ◽  
Epichloë Endophytes

Context Small mammalian herbivores, such as European rabbits (Oryctolagus cuniculus), can have significant unwanted impacts on agriculture and horticulture and can attract birds of prey and avian scavengers to airports, increasing the risk of bird strike. Sustainable wildlife management tools that have high efficacy and animal welfare are needed to mitigate these impacts. Aim We assessed perennial ryegrass (Lolium perenne) and tall fescue (Festuca arundinacea) cultivars associated with selected Epichloë endophytes, originally developed for bird management at airports, to determine their feeding-deterrent properties towards invasive rabbits. Methods A pellet feed trial using caged domestic rabbits and a pen trial using wild rabbits were conducted to assess rabbit responses to food pellets with novel endophyte-infected or uninfected grass seed and to plots planted with endophyte-infected or uninfected grasses, respectively. Key results Caged rabbits ate significantly less food pellets containing endophyte-infected grass straw than pellets containing endophyte-free grass straw. Wild rabbits consumed significantly less herbage from plots planted with endophyte-infected grasses than those of the equivalent endophyte-free grass cultivars. Temporal patterns of rabbit feeding behaviour support the hypothesis that deterrence in rabbits resulted from post-ingestion feedback associated with grass–endophyte secondary metabolites. Conclusions Although more research is required on the exact mechanism of action in rabbits, our results suggest novel endophyte-infected grass associations may substantially reduce rabbit feeding behaviour and possibly rabbit numbers in areas where these grasses are sown. Implications Novel grass–endophyte associations have great potential for deterring problem wildlife at airports and other amenity areas.

scholarly journals Use of Microbial Biostimulants to Increase the Salinity Tolerance of Vegetable Transplants

Agronomy ◽  
2021 ◽  
Vol 11 (6) ◽  
pp. 1143
Author(s):  
Alessandro Miceli ◽  
Alessandra Moncada ◽  
Filippo Vetrano
Keyword(s):  
Salt Stress ◽  
Salinity Tolerance ◽  
Seedling Growth ◽  
Brackish Water ◽  
Biomass Accumulation ◽  
Growth Stages ◽  
Promoting Effect ◽  
Tomato Seedlings ◽  
Negative Effect ◽  
Growth Promoting

Vegetable plants are more sensitive to salt stress during the early growth stages; hence, the availability of poor-quality brackish water can be a big issue for the nursery vegetable industry. Microbial biostimulants promote growth and vigor and counterbalance salt stress in mature plants. This study aimed to evaluate the application of plant growth-promoting microorganisms for improving salt tolerance of lettuce and tomato seedlings irrigated with different water salinity levels (0, 25, and 50 mM NaCl) during nursery growth. Two commercial microbial biostimulants were applied to the substrate before seeding: 1.5 g L−1 of TNC BactorrS13 containing 1.3 × 108 CFU g−1 of Bacillus spp.; 0.75 g L−1 of Flortis Micorrize containing 30% of Glomus spp., 1.24 × 108 CFU g−1 of Agrobacterium radiobacter, Bacillus subtilis, Streptomyces spp. and 3 × 105 CFU g−1 of Thricoderma spp. Many morpho-physiological parameters of lettuce and tomato seedlings suffered the negative effect of salinity. The use of the microbial biostimulants modified seedling growth and its response to salt stress. They had a growth-promoting effect on the unstressed seedlings increasing fresh and dry biomass accumulation, leaf number, and leaf area and were successful in increasing salinity tolerance of seedlings especially when using Flortis Micorizze that enhanced salinity tolerance up to 50 mM NaCl. The inoculation of the substrate with microbial biostimulants could represent a sustainable way to improve lettuce and tomato transplant quality and to use brackish water in vegetable nurseries limiting its negative effect on seedling growth.

scholarly journals Grazing Affects Bacterial and Fungal Diversities and Communities in the Rhizosphere and Endosphere Compartments of Leymus chinensis through Regulating Nutrient and Ion Distribution

2021 ◽  
Vol 9 (3) ◽  
pp. 476
Author(s):  
Yurong Yang ◽  
Siying Chen ◽  
Xuefeng Wu ◽  
Sajid Iqbal Syed ◽  
Irfan Ullah Shah Syed ◽  
...  
Keyword(s):  
High Throughput Sequencing ◽  
Perennial Grass ◽  
Negative Ions ◽  
Leymus Chinensis ◽  
Plant Leaves ◽  
Ion Distribution ◽  
Endophytic Microorganisms ◽  
Natural Grasslands ◽  
Bacteria And Fungi ◽  
Induced Changes

Plant-associated endophytic microorganisms are essential to developing successful strategies for sustainable agriculture. Grazing is an effective practice of grassland utilization through regulating multitrophic relationships in natural grasslands. This study was conducted for exploring the effects of grazing on the diversities and communities of bacteria and fungi presented in rhizosphere soils, roots, stems, and leaves of Leymus chinensis (L. chinensis), based on high-throughput sequencing. Grazing increased bacterial diversity but reduced fungal diversity in plant leaves. Further analysis confirmed that the abundance of Chloroflexi, Gemmatimonadota, Nitrospirota, Sordariales, and Pezizales in plant leaves was increased by grazing. The Bray–Curtis similarities of microbial communities in the endosphere were higher under grazing plots than non-grazing plots. Moreover, the bacterial communities were significantly correlated with ions, while the nutrient and negative ions exhibited strong influence on fungal communities. We concluded that grazing-induced changes of microbial diversities and communities in different compartments of a dominant perennial grass (L. chinensis) could be attributed to the nutrient and ion distribution in host plant. The current study highlights the importance of livestock in mediating diversities and communities of endophytic microbes, and will be useful for better understanding the complexity of multitrophic interactions in a grassland ecosystem.

Sign in / Sign up

Export Citation Format

Share Document