Shoot morphology and alkaloid content of Epichloë endophyte–Festuca sinensis associations

2018 ◽  
Vol 69 (4) ◽  
pp. 430 ◽  
Author(s):  
Tian Pei ◽  
Kuang Yu ◽  
Lin Weihu ◽  
Wang Jianjun ◽  
Nan Zhibiao

The Chinese native cool-season perennial grass species Festuca sinensis Keng ex E.B.Alexeev exhibits frequent asymptomatic infections with an asexual Epichloë fungal endophyte. Six Festuca sinensis ecotypes were collected in different geographical locations. Endophyte-positive (E+) plants and corresponding endophyte-free (E–) plants of these six ecotypes were identified and then measured for shoot morphological characteristics including plant height, tiller number and biomass. Significant difference due to different host ecotype was observed in both E+ and E– plants. However, significant difference due to endophyte was observed in only one or two ecotypes. Concentration of endophyte-derived alkaloids and semi-quantitative endophyte colonisation in E+ plants were also evaluated. All E+ plants produced both lolitrem B and peramine alkaloids, and significant variation in alkaloid concentration due to host ecotype or endophyte genotype was observed. Analysis of semi-quantitative endophyte colonisation by using qPCR revealed significant differences between ecotypes. This suggested that host ecotype had large impacts whereas the endophyte had only a minor effect. The results showed that endophyte, host ecotype and their complex interaction affected performance of Festuca sinensis ecotypes.

2021 ◽  
Vol 52 (2) ◽  
pp. 792-803
Author(s):  
Marit Buhaug Folstad ◽  
Eli Ringdalen ◽  
Halvard Tveit ◽  
Merete Tangstad

AbstractThis work investigates the phase transformations in silica (SiO2) during heating to a target temperature between 1700 °C and 1900 °C and the effect of SiO2 polymorphs on the reduction reaction 2SiO2 + SiC = 3SiO + CO in silicon production. Different heating rates up to target temperature have been used to achieve the different compositions of quartz, amorphous silica and cristobalite. The different heating rates had a minor effect on the final composition, and longer time at temperatures > 1400 °C were necessary to achieve greater variations in the final composition. Heating above the melting temperature gave more amorphous silica and less cristobalite, as amorphous silica also may form from β-cristobalite. Isothermal furnace experiments were conducted to study the extent of the reduction reaction. This study did not find any significant difference in the effects of quartz, amorphous silica or cristobalite. Increased temperature from 1700 °C to 1900 °C increased the reaction rate.


2020 ◽  
Vol 8 (4) ◽  
pp. 498
Author(s):  
Jochen Krauss ◽  
Veronika Vikuk ◽  
Carolyn A. Young ◽  
Markus Krischke ◽  
Martin J. Mueller ◽  
...  

Fungal endophytes of the genus Epichloë live symbiotically in cool season grass species and can produce alkaloids toxic to insects and vertebrates, yet reports of intoxication of grazing animals have been rare in Europe in contrast to overseas. However, due to the beneficial resistance traits observed in Epichloë infected grasses, the inclusion of Epichloë in seed mixtures might become increasingly advantageous. Despite the toxicity of fungal alkaloids, European seed mixtures are rarely tested for Epichloë infection and their infection status is unknown for consumers. In this study, we tested 24 commercially available seed mixtures for their infection rates with Epichloë endophytes and measured the concentrations of the alkaloids ergovaline, lolitrem B, paxilline, and peramine. We detected Epichloë infections in six seed mixtures, and four contained vertebrate and insect toxic alkaloids typical for Epichloë festucae var. lolii infecting Lolium perenne. As Epichloë infected seed mixtures can harm livestock, when infected grasses become dominant in the seeded grasslands, we recommend seed producers to test and communicate Epichloë infection status or avoiding Epichloë infected seed mixtures.


Distribution as well as adaptation of Cynodon dactylon to different ecological zones of Bangladesh is mainly dependant on weather and adaphic factors of their respective habitats. Generally, it is a warm season perennial grass species that initiates growth in the vernal season and its growth continues rapidly when moisture is adequate and they find the alkaline clay soil as their habitat. From that point of view, this study was aimed at analysing the morphological variations of Cynodon dactylon ecotypes along with determining the physicochemical properties of soils from their particular habitats. A total of 19 ecotypes /accessions from four different zones of Bangladesh were collected along with the habitat soil and all of them were transplanted in experimentation field of Institute of Biological Sciences, University of Rajshahi, Bangladesh. All the accessions were established in 1.5 × 1.4 m plots separately. At maturity just after started flowering, the morphological data on 26 characters were recorded quantitatively and those were analysed statistically. Rhizomatous and stoloniferous nature was observed from randomly selected areas within the plot. Both significant and non-significant variations were found among the morphological characters. Most of the vegetative and reproductive characters were found to show significant variations among the accessions. In addition, the values obtained on physio-chemical properties of soil were tabulated and their magnitude were determined and interpreted following Fertilization Recommendation Guide. In respect of soil properties variation on morphological parameters of almost of all the accessions were observed. In this study, all the accessions were found to be adapted nicely in alkaline soil of the experimentation field and that might be due to their many physiological and biochemical mechanisms.


1956 ◽  
Vol 7 (5) ◽  
pp. 367 ◽  
Author(s):  
WD Andrew ◽  
CA Neal-Smith

Over the period 1952-1954 there was no significant difference in the yield of herbage produced annually by the addition to a Phalaris tuberosa L.–Trifolium subterraneum L. pasture mixture, of any one of the following grasses: Agropyron obtusiusculum Lange., Bromus coloratus Steud., Bromus inermis Leyss., Dactylis glomerata L., or Festuca arundinacea Schreb. There were indications of a small change in seasonal production where certain grasses, notably D. glomerata, were included in the mixture. Over the 3-year period the proportion of the sown grass component, in the mixtures where either D. glomerata, B. inermis, or B. coloratus were included, increased by a greater amount than where the simple mixture of phalaris and subterranean clover was used. The addition of each grass also lessened the amount of P. tuberosa in the sown grass component of the yield. In the third year, despite the varying proportions of the phalaris and associated sown grass species, the mean population of the sown perennial grasses in each treatment did not differ significantly from the mean figure of 1.34 plants/sq. lk. The increased production of the sown grass yield component following the association of certain of the above species with P. tuberosa suggests that the latter does not fully exploit the environment. The principle of including another perennial grass when sowing phalaris and subterranean clover might have wide application as a means of combatting "phalaris staggers".


2001 ◽  
Vol 31 (9) ◽  
pp. 1561-1568 ◽  
Author(s):  
J R Nault ◽  
Rene I Alfaro

Terpene levels were measured in bark and wood samples of Sitka spruce (Picea sitchensis (Bong.) Carrière) trees. The trees that had been selected as early or late flushing were subjected to artificial wounding to simulate attack by the white pine weevil, Pissodes strobi (Peck). Samples were taken at four times during the growing season: before wounding, shortly after wounding, and two times later in the season. Terpenes were extracted with hexane and quantified by capillary gas chromatography. There were no significant differences in total bark terpenes between early- and late-flushing trees or between control and wounded trees over all sampling times. There were no significant differences in total wood terpenes between early- and late-flushing trees or among sampling times, but a statistically significant difference was found between control and wounded trees. Eleven individual terpenes accounted for the majority of the terpenes in the extracts. Four bark terpenes showed significant differences with sampling time, two with flushing class, and none with treatment. Five wood terpenes showed significant differences with sampling time, two with flushing class, and nine with treatment. We concluded that flushing had only a minor effect on bark and wood terpene profiles and that wounding significantly increased terpene concentration in wood shortly after injury.


2002 ◽  
Vol 82 (4) ◽  
pp. 731-737 ◽  
Author(s):  
M. A. Bolinder ◽  
D. A. Angers ◽  
G. Bélanger ◽  
R. Michaud ◽  
M. R. Laverdière

Shoot to root ratios (S:R) at peak standing crop are commonly used to estimate the annual crop residue C inputs to the soil from the root biomass left in the soil at harvest. However, root biomass has often been neglected in field studies and estimates of S:R for many commonly grown forage species are not available. Our objective was to determine root biomass and S:R of seven perennial grass species and two perennial legume species under eastern Canadian soil and climatic conditions. Root biomass in three soil layers (0–15, 15–30 and 30–45 cm) was measured shortly after the second harvest in the first (1995) and second (1996) year of production. Two harvests of aboveground DM were taken each year. The total root biomass (0–45 cm) in the second year of production (average of 1437 g m-2) was twice that measured in the first year of production (average of 683 g m-2). This temporal variation was mainly explained by the increase of root biomass in the 0- to 15-cm layer. The proportion of total root biomass (0–45 cm) in the 0- to 15-cm layer increased from 54 to 71% while that in the 15- to 30-cm layer decreased from 37 to 21%; the proportion of roots in the 30- to 45-cm layer remained constant at about 10% in both years. The S:R of alfalfa for the 0- to 15-cm depth was significantly higher than that for most of the grasses. No significant difference in S:R was observed among grass species. Recognizing that S:R may vary with locations and climatic conditions, our results suggest that average S:R of about 1.30 (values ranged from 1.01 to 1.72) in the first production year and 0.60 (values ranged from 0.43 to 0.87) in the second production year could be used as a first approximation to estimate the amount of root biomass left in the soil to a depth of 45 cm from forage crops in eastern Canada. The S:R of forage crops, particularly grasses, were lower than those of annual crops such as small-grain cereals and corn. Key words: Forage, annual C inputs, soil organic matter, root biomass, shoot to root ratios


2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Hiroshi Shinozuka ◽  
Maiko Shinozuka ◽  
Ellen M. de Vries ◽  
Timothy I. Sawbridge ◽  
German C. Spangenberg ◽  
...  

AbstractEvidence for ancestral gene transfer between Epichloë fungal endophyte ancestors and their host grass species is described. From genomes of cool-season grasses (the Poeae tribe), two Epichloë-originated genes were identified through DNA sequence similarity analysis. The two genes showed 96% and 85% DNA sequence identities between the corresponding Epichloë genes. One of the genes was specific to the Loliinae sub-tribe. The other gene was more widely conserved in the Poeae and Triticeae tribes, including wheat (Triticum aestivum L.) and barley (Hordeum vulgare L.). The genes were independently transferred during the last 39 million years. The transferred genes were expressed in plant tissues, presumably retaining molecular functions. Multiple gene transfer events between the specific plant and fungal lineages are unique. A range of cereal crops is included in the Poeae and Triticeae tribes, and the Loliinae sub-tribe is consisted of economically important pasture and forage crops. Identification and characterisation of the 'natural' adaptation transgenes in the genomes of cereals, and pasture and forage grasses, that worldwide underpin the production of major foods, such as bread, meat, and milk, may change the ‘unnatural’ perception status of transgenic and gene-edited plants.


1979 ◽  
Vol 59 (4) ◽  
pp. 1031-1036 ◽  
Author(s):  
A. L. DARWENT ◽  
C. R. ELLIOTT

The size of dandelions (Taraxacum officinale Weber) growing in intermediate wheatgrass (Agropyron intermedium (Host.) Beauv.), crested wheatgrass (A. cristatum L.), a northern biotype of bromegrass (Bromus inermis Leyss.), a southern biotype of bromegrass, meadow fescue (Festuca elatior L.), creeping red fescue (F. rubra var. genuina L.) and timothy (Phleum pratense L.) was effectively reduced by decreasing the row spacing of each grass from 100 cm to 20 cm. Russian wild ryegrass (Elymus junceus Fisch.) had only a minor effect on dandelion size regardless of the row spacing at which it was planted. Within any given row spacing between 20 and 100 cm, dandelion density was not affected by grass species. However, as the row spacing decreased the average density of dandelions growing in the seven grass species also decreased.


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