Stability and Yield of Cool-Season Pasture Grass Species Grown at Five Irrigation Levels

Crop Science ◽  
2002 ◽  
Vol 42 (3) ◽  
pp. 890 ◽  
Author(s):  
Blair L. Waldron ◽  
Kay H. Asay ◽  
Kevin B. Jensen
Crop Science ◽  
2002 ◽  
Vol 42 (3) ◽  
pp. 890-896 ◽  
Author(s):  
Blair L. Waldron ◽  
Kay H. Asay ◽  
Kevin B. Jensen

Genome ◽  
2005 ◽  
Vol 48 (4) ◽  
pp. 637-647 ◽  
Author(s):  
M A. Rouf Mian ◽  
Malay C Saha ◽  
Andrew A Hopkins ◽  
Zeng-Yu Wang

Microsatellites or simple sequence repeats (SSRs) are highly useful molecular markers for plant improvement. Expressed sequence tag (EST)-SSR markers have a higher rate of transferability across species than genomic SSR markers and are thus well suited for application in cross-species phylogenetic studies. Our objectives were to examine the amplification of tall fescue EST-SSR markers in 12 grass species representing 8 genera of 4 tribes from 2 subfamilies of Poaceae and the applicability of these markers for phylogenetic analysis of grass species. About 43% of the 145 EST-SSR primer pairs produced PCR bands in all 12 grass species and had high levels of polymorphism in all forage grasses studied. Thus, these markers will be useful in a variety of forage grass species, including the ones tested in this study. SSR marker data were useful in grouping genotypes within each species. Lolium temulentum, a potential model species for cool-season forage grasses, showed a close relation with the major Festuca–Lolium species in the study. Tall wheatgrass was found to be closely related to hexaploid wheat, thereby confirming the known taxonomic relations between these species. While clustering of closely related species was found, the effectiveness of such data in evaluating distantly related species needs further investigations. The phylogenetic trees based on DNA sequences of selected SSR bands were in agreement with the phylogenetic relations based on length polymorphism of SSRs markers. Tall fescue EST-SSR markers depicted phylogenetic relations among a wide range of cool-season forage grass species and thus are an important resource for researchers working with such grass species.Key words: phylogeny, EST-SSR, forage grasses, tall fescue.


Author(s):  
W.A. Jacques

There are many points of approach to a consideration of root development in pasture plants, but I wish to confine myself to this effect on the root system of different rest periods between the removal of leaves and outline the plants reaction to them


Genome ◽  
2017 ◽  
Vol 60 (12) ◽  
pp. 1086-1088 ◽  
Author(s):  
Hiroshi Shinozuka ◽  
Noel O.I. Cogan ◽  
German C. Spangenberg ◽  
John W. Forster

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.


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.


2011 ◽  
Vol 29 (2) ◽  
pp. 75-80
Author(s):  
Thomas Serensits ◽  
Matthew Cutulle ◽  
Jeffrey F. Derr

Abstract Cool-season grass species are often overseeded into bermudagrass turf for both aesthetics and functionality during the winter months. When the overseeded grass persists beyond the spring, however, it becomes a weed. Experiments were conducted to evaluate overseeded grass species and seeding rate on turf cover during the fall, spring, and summer. The ability of perennial ryegrass, Italian ryegrass, and hybrid bluegrass to then persist in bermudagrass one year after seeding was determined. Both perennial ryegrass and Italian ryegrass produced acceptable ground cover in the spring after fall seeding. Hybrid bluegrass did not establish well, resulting in unacceptable cover. Perennial ryegrass generally had the most persistence one year after seeding, either because of the survival of plants through the summer or because of new germination the following fall. The highest cover seen one year after seeding was 24% with perennial ryegrass in the 2005 trial. Maximum cover seen with Italian ryegrass and hybrid bluegrass 12 months after seeding was 19 and 8%, respectively. Seeding perennial or Italian ryegrass in February achieved acceptable cover in spring in the first trial but not the second. Persistence the following fall, however, was greater in the second trial, suggesting new germination. Percent cover 12 months after seeding tended to increase as the seeding rate increased, also suggesting new germination the following fall. Although quality is lower with Italian ryegrass compared to perennial ryegrass, it transitions out easier than perennial ryegrass, resulting in fewer surviving plants one year after fall seeding.


2004 ◽  
Vol 55 (4) ◽  
pp. 389 ◽  
Author(s):  
K. V. Cunliffe ◽  
A. C. Vecchies ◽  
E. S. Jones ◽  
G. A. Kearney ◽  
J. W. Forster ◽  
...  

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.


2021 ◽  
Vol 17 ◽  
Author(s):  
Tom Maxwell ◽  
Grant Edwards ◽  
Katherine Tozer ◽  
Gerald Cosgrove

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.


1994 ◽  
Vol 4 (3) ◽  
pp. 335-345 ◽  
Author(s):  
Mohammed Tasneem ◽  
Clive A. Cornford ◽  
Michael T. McManus

AbstractA survey of proteinaceous inhibitors of the serine proteinases, bovine trypsin and chymotrypsin, that are extractable from dry seeds of several cultivars of pasture grasses has been undertaken. Using crude extracts, most cultivars screened contained inhibitors of chymotrypsin, whereas trypsin inhibition was not detectable. Seeds from four cultivars, Lolium perenne L. cv. Grasslands Ruanui, Lolium × boucheanum cv. Grasslands Greenstone, Festuca arundinacea Schreb. cultivars Grasslands Roa and Grasslands Garland, that contained more potent chymotrypsin inhibition were purified further. After gel filtration chromatography, both trypsin and chymotrypsin inhibition could be observed in all four cultivars, and each separated into two discrete native molecular weights; one of ca. 20–22 kDa and one of ca. 8–10 kDa. However, activity staining, after polyacrylamide gel electrophoresis, revealed an array of iso-inhibitors with molecular weights that ranged from ca. 3 kDa to 20 kDa. One of these, a dual trypsin/chymotrypsin inhibitor of ca. 12 kDa that is present in all four cultivars examined, was purified to homogeneity from F. arundinacea cv. Grasslands Garland using anhydro-trypsin affinity chromatography and reverse-phase HPLC. The protein was found to comprise two closely related peptides and N-terminal amino acid sequencing revealed highest identity with a trypsin inhibitor identified in rye (Secale cereale) seeds.


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