Detection and characterisation of novel fungal endophyte genotypic variation in cultivars of perennial ryegrass (Lolium perenne L.)

2008 ◽  
Vol 59 (3) ◽  
pp. 214 ◽  
Author(s):  
E. van Zijll de Jong ◽  
M. P. Dobrowolski ◽  
A. Sandford ◽  
K. F. Smith ◽  
M. J. Willocks ◽  
...  
Keyword(s):  
Perennial Ryegrass ◽  
Expressed Sequence Tag ◽  
Genotypic Variation ◽  
Fungal Endophyte ◽  
In Planta ◽  
Pasture Grass ◽  
Grass Endophyte ◽  
Incomplete Removal ◽  
Genotypic Analysis ◽  
Mammalian Herbivore

Alkaloids produced by the perennial ryegrass pasture and turf grass endophyte Neotyphodium lolii confer both beneficial (insect feeding deterrence) and deleterious (mammalian herbivore toxicoses) effects. Novel endophyte strains with altered and desirable in planta metabolic profiles have been introduced into cultivars by inoculation. The potentially severe effects of contamination with standard toxic endophytes provide an important incentive for quality control during varietal development. Genotyping with expressed sequence tag (EST)-derived simple sequence repeat (SSR) markers in order to monitor endophyte content was evaluated in this study. The NEA2 endophyte, described as producing low levels of lolitrem B and moderate quantities of ergovaline and peramine, has been deployed in the cultivar (cv.) Tolosa and transferred to other proprietary varieties by crossing or controlled inoculation. In planta genotypic analysis of cv. Tolosa-derived plants revealed the presence of 2 distinct NEA2 genotypes (A and B). Variable proportions of NEA2 A and B were observed at different stages of cultivar multiplication, and NEA2 B was present in inoculated varieties. Several accessions also revealed the presence of a third genotype (C), identical to standard toxic types. Alkaloid measurement in plants containing individual A and B endophytes identified distinct profiles which collectively account for the average NEA2 profile. The C variant is apparently a contaminant arising from seed or adventitious seedlings during varietal multiplication or incomplete removal of endophyte from seed before inoculation. SSR-based genotyping provides an efficient means to continuously assess endophyte prevalence and identity in pasture grass breeding programs.

scholarly journals Sequence Analysis of SSR-Flanking Regions Identifies Genome Affinities between Pasture Grass Fungal Endophyte Taxa

2011 ◽  
Vol 2011 ◽  
pp. 1-11 ◽  
Author(s):  
Eline van Zijll de Jong ◽  
Kathryn M. Guthridge ◽  
German C. Spangenberg ◽  
John W. Forster
Keyword(s):  
Ssr Markers ◽  
Expressed Sequence Tag ◽  
Fungal Endophytes ◽  
Morphological Characteristics ◽  
Fungal Endophyte ◽  
Fungal Species ◽  
Current View ◽  
Interspecific Hybridisation ◽  
Pasture Grass ◽  
Flanking Regions

Fungal species of the Neotyphodium and Epichloë genera are endophytes of pasture grasses showing complex differences of life-cycle and genetic architecture. Simple sequence repeat (SSR) markers have been developed from endophyte-derived expressed sequence tag (EST) collections. Although SSR array size polymorphisms are appropriate for phenetic analysis to distinguish between taxa, the capacity to resolve phylogenetic relationships is limited by both homoplasy and heteroploidy effects. In contrast, nonrepetitive sequence regions that flank SSRs have been effectively implemented in this study to demonstrate a common evolutionary origin of grass fungal endophytes. Consistent patterns of relationships between specific taxa were apparent across multiple target loci, confirming previous studies of genome evolution based on variation of individual genes. Evidence was obtained for the definition of endophyte taxa not only through genomic affinities but also by relative gene content. Results were compatible with the current view that some asexual Neotyphodium species arose following interspecific hybridisation between sexual Epichloë ancestors. Phylogenetic analysis of SSR-flanking regions, in combination with the results of previous studies with other EST-derived SSR markers, further permitted characterisation of Neotyphodium isolates that could not be assigned to known taxa on the basis of morphological characteristics.

Evaluating the performance of endophytes in farm systems to improve farmer outcomes - a review

2012 ◽  
Vol 63 (10) ◽  
pp. 927 ◽  
Author(s):  
Errol R. Thom ◽  
Alison J. Popay ◽  
David E. Hume ◽  
Lester R. Fletcher
Keyword(s):  
New Zealand ◽  
Perennial Ryegrass ◽  
Insect Pests ◽  
Animal Health ◽  
Small Animal ◽  
Fungal Endophyte ◽  
Feeding Experiments ◽  
Grass Endophyte ◽  
Eastern Australia ◽  
Minimum Requirements

The main plant species relied on for forage supply to grazing animals in New Zealand and south-eastern Australia is perennial ryegrass (Lolium perenne L.). Perennial ryegrass has evolved with a fungal endophyte (Neotyphodium lolii, Latch, Christensen & Samuals) that occupies intercellular spaces, and is nourished by its host. The endophyte (referred to as standard or wild-type) provides the plant with protection from a range of insect pests by producing alkaloids, some of which are also toxic to grazing animals, causing ryegrass staggers and/or exacerbating heat stress. Over the last 20 years naturally occurring perennial ryegrass endophytes have been found in Europe that produce less of the alkaloids that cause animal health problems but have similar or enhanced effects as the standard endophyte on deterring insect attack on infected plants, when introduced into New Zealand and Australian-bred ryegrasses. This review provides a summary of endophyte research in New Zealand from the perspective of insect pests, plants (particularly perennial ryegrass) and the animals grazed on ryegrass-dominant pastures. The protocols used to evaluate perennial ryegrass/endophyte associations over the past 30 years are also discussed. Future testing of new grass/endophyte associations should include the utilisation of more environments for agronomic and entomological experiments; routinely carrying out small animal toxicology assays, and the running of short-term indoor feeding experiments with sheep and cows. Implementation of these changes provides the minimum requirements for strengthening the evaluation of new endophyte associations so farmers using these technologies, gain optimal benefits from their adoption.

scholarly journals A Simple LC–MS Method for the Quantitation of Alkaloids in Endophyte-Infected Perennial Ryegrass

Toxins ◽  
2019 ◽  
Vol 11 (11) ◽  
pp. 649 ◽  
Author(s):  
Vassiliadis ◽  
Elkins ◽  
Reddy ◽  
Guthridge ◽  
Spangenberg ◽  
...  
Keyword(s):  
Perennial Ryegrass ◽  
Limit Of Detection ◽  
Rapid Identification ◽  
In Planta ◽  
Pasture Grass ◽  
Agricultural Industry ◽  
Highly Sensitive ◽  
Limit Of Quantitation ◽  
Lolitrem B ◽  
Epichloë Endophyte

The rapid identification and quantitation of alkaloids produced by Epichloë endophyte-infected pasture grass is important for the agricultural industry. Beneficial alkaloids, such as peramine, provide the grass with enhanced insect protection. Conversely, ergovaline and lolitrem B can negatively impact livestock. Currently, a single validated method to measure these combined alkaloids in planta does not exist. Here, a simple two-step extraction method was developed for Epichloë-infected perennial ryegrass (Lolium perenne L.). Peramine, ergovaline and lolitrem B were quantified using liquid chromatography–mass spectrometry (LC–MS). Alkaloid linearity, limit of detection (LOD), limit of quantitation (LOQ), accuracy, precision, selectivity, recovery, matrix effect and robustness were all established. The validated method was applied to eight different ryegrass-endophyte symbiota. Robustness was established by comparing quantitation results across two additional instruments; a triple quadruple mass spectrometer (QQQ MS) and by fluorescence detection (FLD). Quantitation results were similar across all three instruments, indicating good reproducibility. LOQ values ranged from 0.8 ng/mL to 6 ng/mL, approximately one hundred times lower than those established by previous work using FLD (for ergovaline and lolitrem B), and LC–MS (for peramine). This work provides the first highly sensitive quantitative LC–MS method for the accurate and reproducible quantitation of important endophyte-derived alkaloids.

scholarly journals Reference transcriptome assembly and annotation for perennial ryegrass

Genome ◽  
2017 ◽  
Vol 60 (12) ◽  
pp. 1086-1088 ◽  
Author(s):  
Hiroshi Shinozuka ◽  
Noel O.I. Cogan ◽  
German C. Spangenberg ◽  
John W. Forster
Keyword(s):  
Perennial Ryegrass ◽  
Transcriptome Assembly ◽  
Genotyping By Sequencing ◽  
Whole Genome Sequence ◽  
Grass Species ◽  
Rna Seq ◽  
Pasture Grass ◽  
Tissue Samples ◽  
Genome Sequence Assembly ◽  
Transcriptome Resource

RNA-Seq methodology has been used to generate a comprehensive transcriptome sequence resource for perennial ryegrass, an important temperate pasture grass species. A total of 931 547 255 reads were obtained from libraries corresponding to 19 distinct tissue samples, including both vegetative and reproductive stages of development. Assembly of data generated a final filtered reference set of 48 713 contigs and scaffolds. The transcriptome resource will support whole genome sequence assembly, comparative genomics, implementation of genotyping-by-sequencing (GBS) methods based on transcript sampling, and identification of candidate genes for multiple biological functions.

Characterisation of the WSC fraction of six species of temperate pasture grass

2004 ◽  
Vol 32 ◽  
pp. 247-248
Author(s):  
J. C. Ince ◽  
A. C. Longland ◽  
A. J. Cairns ◽  
M. Moore–Colyer
Keyword(s):  
Perennial Ryegrass ◽  
Water Soluble ◽  
Italian Ryegrass ◽  
Soluble Carbohydrate ◽  
Meadow Fescue ◽  
Pasture Grass ◽  
Pasture Grasses ◽  
Optimal Health ◽  
Water Soluble Carbohydrate ◽  
Field Plots

The carbohydrate (CHO) fraction of pasture grasses is a major source of energy for many domestic herbivores. However, the amounts, and types, of the water–soluble carbohydrate (WSC) fraction (i.e. glucose, fructose, sucrose, and polymers of sucrose and fructose, the fructans) present in such grasses, varies with species and environmental conditions. As the WSC constitute a highly digestible, energy yielding fraction of grasses, it is important to be able to measure their levels in a sward so that the diets of pastured animals may be designed to elicit optimal health and productivity. The aim of this study was to characterise the WSC profile of six UK pasture grasses, and to develop a technique for extracting the fructan portion of the WSC.Six species of UK pasture grasses [Cocksfoot (C), Timothy (T), Meadow Fescue (M), Italian Ryegrass (IR), Perennial Ryegrass (PR) and Hybrid Ryegrass (HR)] were grown in experimental field plots at IGER.

Assessment of gene flow using tetraploid genotypes of perennial ryegrass (Lolium perenne L.)

2004 ◽  
Vol 55 (4) ◽  
pp. 389 ◽  
Author(s):  
K. V. Cunliffe ◽  
A. C. Vecchies ◽  
E. S. Jones ◽  
G. A. Kearney ◽  
J. W. Forster ◽  
...  
Keyword(s):  
Gene Flow ◽  
Seed Production ◽  
Lolium Perenne ◽  
Perennial Ryegrass ◽  
Grass Species ◽  
Numerical Representation ◽  
Pasture Grass ◽  
Important Species ◽  
Lolium Perenne L ◽  
Total Seed

Ryegrass species are among the most important species in sown pastures, turf settings, and weed populations worldwide. Perennial ryegrass (Lolium perenne L.) is an outcrossing, wind-pollinated grass. Recent research has demonstrated the feasibility of developing transgenic perennial ryegrass varieties. In order to model the consequences of gene flow from transgenic grass genotypes in a field situation, the model non-transgenic trait of fertility among autotetraploid genotypes was chosen. Gene flow over distance and direction from a donor plot to surrounding sexually compatible recipient plants was studied. Reproductive isolation was achieved through the fertility barrier that arises between tetraploid and diploid ryegrass genotypes, despite the presence of diploid plants in a meadow situation. Fertility was used as an indication of effective gene flow over distance and direction. Measures of the fertility of recipient plants included total seed production (TSP), floret site utilisation (FSU), and relative fertility of recipient plants as a percentage of those within the donor plot (RF%). A leptokurtic distribution for gene flow was identified, with differences in the rate of decline over distance depending on direction. Simple sequence repeat (SSR) polymorphism was used to identify the paternity of progeny plants. The proportional representation of parents among the progeny was not significantly different from that expected due to the numerical representation of the different donor parent genotypes. The results of this research will have important implications for risk analysis prior to the field release of transgenic ryegrasses, fescues, and other pasture grass species, and for seed production in terms of cultivar purity and optimum isolation distance.

Persistence of perennial ryegrass, tall fescue and cocksfoot following annual sowings: influence of grass species, ryegrass cultivar and pasture age on yield, composition and density

2021 ◽  
Vol 17 ◽  
Author(s):  
Tom Maxwell ◽  
Grant Edwards ◽  
Katherine Tozer ◽  
Gerald Cosgrove
Keyword(s):  
Perennial Ryegrass ◽  
Tall Fescue ◽  
Grass Species ◽  
Botanical Composition ◽  
Release Date ◽  
Confounding Effect ◽  
Pasture Grass ◽  
Age Cohort ◽  
Tiller Density ◽  
Pasture Age

Persistence is an important component of perennial pasture-grass productivity. Defining traits that affect persistence is essential for improving pasture longevity through plant breeding and for identifying persistence traits that should be included in cultivar ranking indices. Compared with conventional longitudinal studies, where a single sowing is monitored over time, repeated annual sowings allow the effects on persistence of sowing year and the ensuing interactions between environment and age of pasture to be identified. An experiment was commenced in 2015 under sheep grazing in Canterbury and in 2016 under cattle grazing in Waikato, where eight cultivars of perennial ryegrass representing different ploidy, flowering date, and cultivar age (release date), and one cultivar each of tall fescue and cocksfoot were sown in four randomised complete blocks in autumn each year. This paper reports interim data on spring and autumn pasture yield, composition, and density of 3-year-old, 2-year-old and 1-year-old pastures exposed to the same environmental conditions within the same, single year. There were significant effects on yield, botanical composition, basal cover and tiller density due to cultivar, pasture age, and their interaction. When the confounding effect of year-to-year variation was removed by comparing each age cohort in the same year, the underlying differences among grass species and cultivars, and ages of pasture, is starting to reveal the nature of this influence on pasture persistence.

scholarly journals A QTL analysis of host plant effects on fungal endophyte biomass and alkaloid expression in perennial ryegrass

2015 ◽  
Vol 35 (8) ◽  
Author(s):  
Marty J. Faville ◽  
Lyn Briggs ◽  
Mingshu Cao ◽  
Albert Koulman ◽  
M. Z. Zulfi Jahufer ◽  
...  
Keyword(s):  
Host Plant ◽  
Perennial Ryegrass ◽  
Qtl Analysis ◽  
Fungal Endophyte ◽  
Plant Effects
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