Articoli di riviste: "Eragrostis curvula"

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Carballo, Jose, Diego Zappacosta, Juan Pablo Selva, Mario Caccamo e Viviana Echenique. "Eragrostis curvula, a Model Species for Diplosporous Apomixis". Plants 10, n. 9 (31 agosto 2021): 1818. http://dx.doi.org/10.3390/plants10091818.

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Eragrostis curvula (Schrad.) Ness is a grass with a particular apomictic embryo sac development called Eragrostis type. Apomixis is a type of asexual reproduction that produces seeds without fertilization in which the resulting progeny is genetically identical to the mother plant and with the potential to fix the hybrid vigour from more than one generation, among other advantages. The absence of meiosis and the occurrence of only two rounds of mitosis instead of three during embryo sac development make this model unique and suitable to be transferred to economically important crops. Throughout this review, we highlight the advances in the knowledge of apomixis in E. curvula using different techniques such as cytoembryology, DNA methylation analyses, small-RNA-seq, RNA-seq, genome assembly, and genotyping by sequencing. The main bulk of evidence points out that apomixis is inherited as a single Mendelian factor, and it is regulated by genetic and epigenetic mechanisms controlled by a complex network. With all this information, we propose a model of the mechanisms involved in diplosporous apomixis in this grass. All the genetic and epigenetic resources generated in E. curvula to study the reproductive mode changed its status from an orphan to a well-characterised species.

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Rabau, T., B. Longly e B. P. Louant. "Ontogenèse des sacs embryonnaires non réduits chez Eragrostis curvula". Canadian Journal of Botany 64, n. 8 (1 agosto 1986): 1778–85. http://dx.doi.org/10.1139/b86-237.

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The apomictic reproductive mode by diplospory is cytologically analysed in Eragrostis curvula (Schrad.) Nees, a tetraploid forage grass. The genesis of unreduced embryo sacs is followed; two kinds of sacs are then distinguished: (i) a monopolar one with a typical oogonial complex and a polar nucleus at the micropylar end; (ii) a bipolar one with an egg cell and two polar nuclei at the micropylar end, and some antipodial cells at the chalazal end. Monopolar sacs are 3 times more frequent than bipolar ones. Traces of sexuality are noted in E. curvula but with a low frequency. A chronology of female development is established according to stages of male development. This should make possible an early distinction and allow a useful comparison between diplospory and sexuality within the genus Eragrostis.

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Johnston, W. H., e V. F. Shoemark. "Establishment and persistence of palatable taxa of Eragrostis curvula complex in southern New South Wales". Australian Journal of Experimental Agriculture 37, n. 1 (1997): 55. http://dx.doi.org/10.1071/ea96025.

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Summary. Spring sowings in cultivated plots at Wagga Wagga in 1980 and 1982, and Cowra and Colinroobie in 1980 and 1981 examined the establishment and persistence of Eragrostis curvula (Schrad.) Nees complex cv. Consol and accession 4660, Cenchrus ciliaris L. cv. American and Phalaris aquatica L. cv. Sirocco. Cenchrus ciliaris was short-lived and not frost-hardy. Competition and dry conditions reduced establishment of all species, nevertheless E. curvula established reliably. In 1 experiment where conditions were not immediately favourable for germination, E. curvula demonstrated a capacity to delay establishment until conditions improved. Competition from cool-season plants reduced persistence, particularly in the first year and when conditions were dry. Surviving E. curvula plants were generally long lived. At Cowra, the density of E. curvula was enhanced by regular mowing, but mowing reduced the density of P. aquatica. Presence of Trifolium subterraneum L. reduced the density of E. curvula while P. aquatica was unaffected. A second experiment at Colinroobie, sown in October 1987 examined the effects of mowing and fertiliser application on establishment and persistence of E. curvula cv. Consol and accession 4660. Fertiliser increased competition by cool-season annual species, reducing establishment and persistence of E. curvula, while regular mowing improved its persistence. In an experiment sown at Wagga Wagga in October 1989, E. curvula cv. Consol establishment was very low (<1 plant/m2) in undisturbed annual pasture and in the absence of cultivation, herbicide (glyphosate at 530 g a.i./ha) and mowing with herbage removal provided the best conditions for establishment.

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4

DI RENZO, M. A., M. A. IBAÑEZ, N. C. BONAMICO e M. M. POVERENE. "Estimation of repeatability and phenotypic correlations in Eragrostis curvula". Journal of Agricultural Science 134, n. 2 (marzo 2000): 207–12. http://dx.doi.org/10.1017/s0021859699007522.

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Eragrostis curvula (Schrad.) Nees s. lat., a highly polymorphic polyploid complex, can be considered as one of the most important warm season perennial grasses for the semi-arid regions of central Argentina. In apomictically propagated and perennial plants such as weeping lovegrass, where successive measurements can be done across time, repeatability estimates provide an indication of the degree of influence of permanent effects on the phenotypic variation and allow prediction of future performance from past records. Analysis of variance of the experiment showed highly significant variation (P < 0·01) for the main factors in all four traits. Although there was very high variability between cuts, hybrids of E. curvula exhibited considerable inter-entry variability, in particular for those traits determining forage yield. Repeatability calculated in this experiment was highest for the crown diameter (0·86), leaf length (0·84) and dry matter (0·84), while in panicle number (0·66) it was lowest. Repeatability estimates for the vegetative characteristics indicate small effects of temporal environment. The four traits studied, including panicle number with their moderate repeatability, do not require an essentially different number of observations to obtain measures at the same level of accuracy. For vegetative characters two harvests provided 98% of the accuracy of the total obtained with four cuts, and for panicle number the same percentage was obtained for three harvests. This stability of performance is a desirable characteristic for grass cultivars. Patterns of trait associations were also described. Because leaf length is closely associated with dry matter and has high repeatability, to use leaf length as an indirect evaluation criterion should be almost as efficient as direct evaluation for aerial biomass yield. Reliable estimates of parameters such as repeatability and phenotypic correlation are needed for prediction of production values and for the design of efficient improvement programmes. For genotype evaluation additional research is required to quantify the extent of genotype × environment interaction across years and localities of semi-arid regions.

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Johnston, W. H., T. B. Koen e V. F. Shoemark. "Water use, competition and a temperate-zone C4 grass (Eragrostis curvula (Schrad.) Nees. complex) cv. Consol". Australian Journal of Agricultural Research 53, n. 6 (2002): 715. http://dx.doi.org/10.1071/ar98115.

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The effects of a perennial C4 grass (Eragrostis curvula [Schrad.] Nees. complex cv. Consol) and winter-growing annual pasture on the soil water deficit (SWD) was assessed at 2 sites near Wagga Wagga, NSW. At Site A, newly sown E. curvula-Trifolium subterraneum L. pasture was compared with an annual pasture containing Lolium rigidum Gaud. and T. subterraneum. A mature E. curvula pasture sown 10 years previously was compared with an adjacent volunteer annual pasture at Site B. The annual pasture at Site A had little effect on the SWD at 120 cm depth, but it developed an appreciable SWD at 60 cm on 2 occasions when spring rainfall was well below average. This deficit was not evident the following autumn. When E. curvula was present in the pasture, it developed a substantial SWD at 120 cm in summer and autumn. This represented a significant realignment of the water balance that had the potential to reduce deep drainage. The size of the SWD in autumn determined how rapidly soils reached field capacity in winter. At Site B, E.�curvula consistently created a deficit of between 108 and 124 mm to 100 cm depth in autumn, compared with 2-106 mm for the annual pasture. The soil profile under E. curvula did not reach field capacity until 60-100 days later than the annual pasture. The annual pasture at Site B had a minimal effect on the SWD at 100 cm in 3 of the 4 years of the study. The camping behavior of sheep at Site A caused E. curvula to succumb to competition from T. subterraneum, Hordeum leporinum Link, and Cryptostemma calendula (L.) Druce. Competitive interactions between T.�subterraneum cv. Junee and Eragrostis curvula cv. Consol were therefore investigated in a glasshouse study using the de Wit replacement series methodology. Pots were watered to weight and water usage was recorded under 2 levels of watering [low (restricted watering) and high (watered to field capacity)] that were applied after an establishment period of 6 weeks. Pots were harvested after a further c.12 weeks and above- and below-ground yield of each species determined. T. subterraneum tended to use water up to the limit of its supply, and as water became less available and in response to increasing atmospheric water demand in spring, it frequently wilted. E. curvula rarely wilted; it exhibited water-saving strategies, including leaf waxing and leaf rolling in the heat of the day in response to increasing water demand without necessarily exhausting its water supply. Both species used water more efficiently (dry matter/kg water used) when its supply was limited. The water use efficiency of monoculture T. subterraneum was greater than that of slowly growing E. curvula, and both species used water most efficiently when growing alone. T. subterraneum was highly competitive against E. curvula. Competition resulted from its out-of-phase growth compared with E. curvula. E. curvula has the potential to markedly affect on the water balance. However, it is vulnerable to competition. Managing the flush of growth in spring is an important issue in maintaining a balance between E. curvula and winter-growing annual species.

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6

Johnston, WH. "Palatability to sheep of the Eragrostis curvula complex. 2. Selection of palatable taxa". Australian Journal of Experimental Agriculture 28, n. 1 (1988): 47. http://dx.doi.org/10.1071/ea9880047.

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Relative palatability of 12 previously selected taxa of Eragrostis curvula complex was assessed using a visual rating scale of 0 (not grazed) to 10 (completely grazed). Visual ratings were converted to ranks and the most and least palatable lines were compared over 19 grazing assessments in trials at Wagga Wagga, Temora and Orange, New South Wales. Three highly palatable and 2 acceptably palatable accessions were identified. The importance of palatability in the E. curvula complex is discussed.

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7

Johnston, W. H., P. S. Cornish, T. B. Koen e V. F. Shoemark. "Eragrostis curvula (Schrad.) Nees. complex pastures in southern New South Wales, Australia: a comparison of Eragrostis curvula cv. Consol and Medicago sativa L. cv. Nova under intensive rotational management". Australian Journal of Experimental Agriculture 45, n. 10 (2005): 1255. http://dx.doi.org/10.1071/ea04080.

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The productivity, carrying capacity and liveweight performance of wether sheep grazing pastures of Eragrostis curvula cv. Consol and Medicago sativa cv. Nova, which were also sown with annual grasses and Trifolium subterraneum, were compared under an intensive 4-paddock rotational grazing regime in a ‘put-and-take’ grazing experiment at Wagga Wagga, New South Wales from November 1993 to August 1996. The productivity of the pastures was broadly similar, with production peaks of >1000 kg/ha in winter and >3000 kg/ha in spring and summer in paddocks that had been spelled for 6 weeks. Although annual species contributed a high proportion of the total herbage mass in spring, over the remainder of the year, both pastures were dominated by their respective perennials. E. curvula maintained an average plant density of approximately 20 plants/m2. The density of M. sativa declined noticeably during the 3 years, and at the end of the experiment M. sativa plants in 1 replicate of the experiment were killed by rising groundwater and dryland salinity. The long-term average stocking rate of E. curvula and M. sativa pastures were similar (12.1 v. 12.5 sheep/ha) and both pastures were capable of sustaining high stocking rates for lengthy periods in spring and summer. Sheep grazing M. sativa tended to be heavier than animals grazing E. curvula, and they produced, on average, 1.1 kg (or 21%) more wool. However, M. sativa was more difficult to establish and its costs for weed and insect control were higher. Therefore, although it was more productive, it might not have been the most economically viable of the 2 pastures. The implications of the findings were discussed within a whole-farm context and it was concluded that E. curvula has a complimentary role to M. sativa for sowing on landscapes and in situations to which M. sativa is poorly adapted.

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8

Campbell, MH, JJ Dellow, MJ Keys e AR Gilmour. "Use of herbicides for selective removal of Eragrostis curvula (Schrad.) Nees from a Phalaris aquatica pasture". Australian Journal of Experimental Agriculture 25, n. 3 (1985): 665. http://dx.doi.org/10.1071/ea9850665.

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In the main experiment, the effectiveness of tetrapion, glyphosate and 2,2-DPA in selectively removing Eragrostis curvula from a Phalaris aquatica pasture was determined by applying each at three rates in July 1980, September 1980, December 1980 and March 1981 near Braidwood, New South Wales. Auxiliary experiments were conducted from April 1981 to April 1983 to determine the reliability of herbicide effect on E. curvula. Tetrapion (2.25 and 3.375 kg/ha a.i.) was the most effective herbicide in killing E. curvula and promoting P. aquatica and Trifolium subterraneum. It was more selective when applied in September 1980 and December 1980 than when applied in July 1980 or March 198 1. Re-infestation by E. curvula seedlings in the 3 years after spraying with tetrapion amounted to a maximum of 3% of ground cover. In the auxiliary experiments, tetrapion was effective on all nine occasions of application, which demonstrated its reliability and effectiveness at any time of the year. Glyphosate (1.08 and 1.62 kg/ha a.i.) was effective in killing E. curvula in March 1981 but this result could not be repeated in March 1982 or March 1983 or in nine other applications at other times in these years. 2,2-DPA (maximum rate 22.2 kg/ha a.i.) was ineffective in killing E. curvula at four times of application. Recovery of the P. aquatica pasture after treatment declined in the order: tetrapion >2,2-DPA>glyphosate.

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Burson, Byron L., e Paul W. Voigt. "Cytogenetic Relationships between the Eragrostis curvula and E. lehmanniana Complexes". International Journal of Plant Sciences 157, n. 5 (settembre 1996): 632–37. http://dx.doi.org/10.1086/297384.

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Rodrigo, Juan Manuel, Diego Carlos Zappacosta, Juan Pablo Selva, Ingrid Garbus, Emidio Albertini e Viviana Echenique. "Apomixis frequency under stress conditions in weeping lovegrass (Eragrostis curvula)". PLOS ONE 12, n. 4 (18 aprile 2017): e0175852. http://dx.doi.org/10.1371/journal.pone.0175852.

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Poverene, María Mónica, e Paul Warren Voigt. "Isozyme variation and germplasm relationships in the Eragrostis curvula complex". Biochemical Systematics and Ecology 25, n. 1 (gennaio 1997): 21–32. http://dx.doi.org/10.1016/s0305-1978(96)00089-0.

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Echenique, V., P. Polci e L. Mroginski. "Plant regeneration in weeping lovegrass, (Eragrostis curvula) through inflorescence culture". Plant Cell, Tissue and Organ Culture 46, n. 2 (agosto 1996): 123–30. http://dx.doi.org/10.1007/bf00034845.

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Campbell, MH, HW Kemp, RD Murison, JJ Dellow e H. Ridings. "Use of herbicides for selective removal of Eragrostis curvula (Schrad.) Nees from a Pennisetum clandestinum pasture". Australian Journal of Experimental Agriculture 27, n. 3 (1987): 359. http://dx.doi.org/10.1071/ea9870359.

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In 3 experiments near Candelo, New South Wales, the effectiveness of tetrapion, glyphosate and 2,2-DPA in selectively removing Eragrostis curvula (agronomic type Tall Chloromelas) from a Pennisetum clandestinurn pasture was determined by applying each at various rates in each season of the year in 1981-82 (experiments 1 and 2) and in 1983 (experiment 3). Experiment 4 examined the effect of the herbicides on 3 cultivars of P. clandestinum when applied in each season in 1983-84. Tetrapion (2.25 and 3.00 kg/ha a.i.) was the most effective herbicide in killing E. curvula and promoting P. clandestinum in experiments 1 and 2, but, in experiment 3, glyphosate and 2,2-DPA were equally effective in killing E, curvula at 3 (glyphosate) and 2 (2,2-DPA) of the 4 application times. The differences between the results of the experiments were attributed to the herbicide being leached faster by the higher rainfall and being immobilised by the greater amounts of dead foliage of E. curvula in experiment 3. Despite occasional success in killing E. curvula, glyphosate and 2,2-DPA could not be considered for selective use as both were much more phytotoxic to P. clandestinum than tetrapion (experiment 4). Time of application had little influence on the selectivity of tetrapion, the least effective being May-June. In experiments 1 and 2, E. curvula was still well controlled by P. clandestinurn 5 years after the application of tetrapion. Pennisetum clandestinum cv. Crofts was more tolerant of tetrapion than were cvv. Whittet or Common.

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du Toit, C. J. L., W. A. van Niekerk, H. H. Meissner, L. J. Erasmus e R. J. Coertze. "Methane emissions from sheep fed Eragrostis curvula hay substituted with Lespedeza cuneata". Animal Production Science 60, n. 15 (2020): 1777. http://dx.doi.org/10.1071/an19257.

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Context Reducing emissions of greenhouse gases from livestock production systems is a global research priority. Forages that contain condensed tannins, such as the perennial legume Lespedeza cuneata, may help to reduce ruminant methane (CH4) emissions. Aims The objective of this study was to investigate the effect of feeding different levels of L. cuneata hay on feed intake and enteric CH4 emissions of sheep fed a basal diet of subtropical Eragrostis curvula hay. Methods Four adult ruminally cannulated Dohne Merino wethers with initial bodyweight of 65.5 ± 3.5 kg were used in the experiment in a 4 × 4 Latin square design. The four experimental treatments were E. curvula hay substituted with 0%, 30%, 60% and 90% L. cuneata hay. Each of four experimental periods lasted 27 days, which consisted of a 14-day adaptation period, a 7-day digestibility trial, and a 6-day CH4-measurement period. During the 6-day CH4-measurement period, CH4 emissions were measured continuously over a 24-h period by using an open circuit respiration system. Key results Dry matter intake (DMI, g/kg W0.75) was higher (P < 0.05) for sheep receiving 60% and 90% L. cuneata than 0% and 30% L. cuneata (77.33 and 84.67 g/kg W0.75 vs 62.96 and 62.71 g/kg W0.75). The increase in DMI corresponded with a linear increase in DM digestibility of the experimental treatments from 38% to 45% as the level of L. cuneata substitution increased. Methane yield was not influenced (P > 0.05) by 30% inclusion of L. cuneata (17.6 g CH4/kg DMI) but decreased (P < 0.05) as the inclusion level increased to 60% and 90% (13.8 and 14.3 g CH4/kg DMI). Conclusions Inclusion of L. cuneata hay in a diet based on E. curvula hay improved diet digestibility, and led to increased concentrations of crude protein, neutral detergent fibre and non-fibre carbohydrates. Substituting E. curvula hay with 60% L. cuneata on a DM basis resulted in the greatest reduction in CH4 yield of 21.4% compared with a diet of 100% E. curvula. Implications The results suggest that L. cuneata has the potential to reduce CH4 yield and possibly increase production from sheep by improving diet DM digestibility and through improved DMI.

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Johnston, W. H., e P. S. Cornish. "Eragrostis curvula (Schrad.) Nees. complex pastures in southern New South Wales, Australia: impact of Eragrostis curvula, Medicago sativa L. and Phalaris aquatica L. pastures on soil water". Australian Journal of Experimental Agriculture 45, n. 10 (2005): 1267. http://dx.doi.org/10.1071/ea04115.

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Gypsum blocks were used to monitor soil water under 5 rotationally grazed pastures [Eragrostis curvula cvv. 4650, 4660 and Consol; Medicago sativa cv. Aurora and Phalaris aquatica (a 50/50 mixture of cvv. Uneta and Sirolan)] at depths of 15, 30, 60 and 120 cm at Wagga Wagga in southern NSW, Australia from 18 December 1993 to 23 November 1998. At 120 cm depth, soil matric potential (ψ) varied from approximately –14 kPa in winter and spring, to less than –1500 kPa in autumn. During 2 droughts the soil remained drier than its water holding capacity limit, but when rainfall was average or above average, there was no evidence that deficits were maintained through winter. The nature of the rainfall (rainfall/day and numbers of consecutive wet days), which varies through the seasons, impacted markedly on ψ, with considerable short-term variation observed in response to isolated heavy rainfall events in summer and autumn. Medicago sativa cv. Aurora generated lower ψ than E. curvula in mid- to late-spring; whereas except for 4650, which was not persistent at the site, E. curvula reduced ψ in early to mid-summer, and to generally more negative extremes than by M. sativa. There was no indication that the roots of P. aquatica did not extend to the same depths as the other pastures, but it seemed unable to dry the soil to the same extent. Summer-active weeds, which were prominent in the P. aquatica pasture in years of above average rainfall, reduced the deficit difference between it and the other pastures. Gypsum block ψ was converted to volumetric soil water content (θv) using soil water retention curves and estimates of soil bulk density (ρb). Relative to P. aquatica, E. curvua Consol and M. sativa maintained a deficit of between 25 and 75 mm for most non-winter periods. There was no evidence that the deficit created by either pasture was consistently greater than the other. There was considerable dynamism within the datasets for all the pastures, which was ascribed to the frequent occurrence of non-matrix flow, mainly in response to heavy rainfall events (>25 mm in <5 days) that occurred when the soil was dry in summer and autumn. In the long-term it was estimated that such events could be associated with up to 25% of the rainfall.

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Msiza, Ntokozo Happy, Khuliso Emmanuel Ravhuhali, Hilda Kwena Mokoboki, Sydney Mavengahama e Lebogang Ezra Motsei. "Ranking Species for Veld Restoration in Semi-Arid Regions Using Agronomic, Morphological and Chemical Parameters of Selected Grass Species at Different Developmental Stages under Controlled Environment". Agronomy 11, n. 1 (29 dicembre 2020): 52. http://dx.doi.org/10.3390/agronomy11010052.

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The establishment of complementary native grass species could be an ideal method of dealing with existing problems of veld degradation and inadequate forage quantity and quality of pastures. A greenhouse experiment was conducted to evaluate the effect of native grasses viz., Anthephora pubescens, Cenchrus ciliaris, Chloris gayana, Dactylis glomerata, Digitaria eriantha, Eragrostis curvula, Festuca arundinacea, Panicum maximum and Themeda triandra. Attributes at different growth stages on agronomy, morphology and chemical composition were checked. Panicum maximum had the broader (p < 0.05) leaves across all growth stages when compared to all other grass species. Festuca arundinacea had highest (p < 0.05) number of tillers than C. ciliaris, C. gayana, D. glomerata, D. eriantha, E. curvula, P. maximum and T. triandra at 2–4-months age. Within each species, all grasses had the highest (p < 0.05) number of leaves at maturity. Chloris gayana, D. glomerata and P. maximum had the highest (p < 0.05) biomass yield when compared to F. arundinacea at the elongation stage. Eragrostis curvula had the highest (p < 0.05) crude protein (CP) values when compared to all other grasses, except for D. glomerata, F. arundinacea and P. maximum at the elongation stage. Panicum maximum and T. triandra had the least (p < 0.05) acid detergent lignin (ADL) values when compared to all other grasses at both vegetative and the elongation stages. In the ranking, C. ciliaris, C. gayana, D. eriantha, E. curvula, P. maximum and A. pubescens outperformed the rest of the grasses on most parameters. With the low crude protein (CP) content of these grasses, protein supplementation is highly crucial for high performing ruminants, especially those animals that graze grasses as their sole diets.

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D, Zappacosta, M. Meier, A. Carrera, G. Pacheco, S. Cardone, JP Selva e V. Echenique. "Molecular markers to study the variability within the Eragrostis curvula complex". Phyton 80, n. 1 (2011): 211–20. http://dx.doi.org/10.32604/phyton.2011.80.211.

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Ngoy, Kikombo Ilunga, e Daniela Shebitz. "Characterizing the Spatial Distribution of Eragrostis Curvula (Weeping Lovegrass) in New Jersey (United States of America) Using Logistic Regression". Environments 6, n. 12 (15 dicembre 2019): 125. http://dx.doi.org/10.3390/environments6120125.

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The increasing spread of invasive plants has become a critical driver of global environmental change. Once established, invasive species are often impossible to eradicate. Therefore, predicting the spread has become a key element in fighting invasive species. In this study, we examined the efficiency of a logistic regression model as a tool to identify the spatial occurrence of an invasive plant species. We used Eragrostis curvula (Weeping Lovegrass) as the dependent variable. The independent variables included temperature, precipitation, soil types, and the road network. We randomly selected 68 georeferenced points to test the goodness of fit of the logistic regression model to predict the presence of E. curvula. We validated the model by selecting an additional 68 random points. Results showed that the probability to successfully predict the presence of E. Curvula was 82.35%. The overall predictive accuracy of the model for the presence or absence of E. Curvula was 80.88%. Additional tests including the Chi-square test, the Hosmer–Lemeshow (HL) test, and the area under the curve (AUC) values, all indicated that the model was the best fit. Our results showed that E. curvula was associated with the identified variables. This study suggests that the logistic regression model can be a useful tool in the identification of invasive species in New Jersey.

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Ochogavía, Ana C., Gerardo Cervigni, Juan P. Selva, Viviana C. Echenique e Silvina C. Pessino. "Variation in cytosine methylation patterns during ploidy level conversions in Eragrostis curvula". Plant Molecular Biology 70, n. 1-2 (22 gennaio 2009): 17–29. http://dx.doi.org/10.1007/s11103-009-9454-5.

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Johnston, WH. "Palatability to sheep of the Eragrostis curvula complex. 3. A comparison of naturalised and selected taxa". Australian Journal of Experimental Agriculture 28, n. 1 (1988): 53. http://dx.doi.org/10.1071/ea9880053.

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The palatability of 20 accessions of E. curvula collected from naturalised populations in New South Wales was compared on 7 occasions with 2 selected accessions previously found to be highly palatable. The experiment was conducted at Wagga Wagga, N.S.W., between January 198 1 and July 1983. The relative palatability of most accessions was substantially similar from rating to rating, despite differences in the extent to which the trial was grazed. Palatability was related to the agronomic group to which the accessions belonged. For the naturalised taxa, Curvula was ranked equal to Tall Chloromelas. but both were more palatable than Short Chloromelas. The naturalised accessions were all less palatable than the selected accessions. It was concluded that the selected accessions were sufficiently palatable to be well utilised in pastures by stock grazing at commercial stocking rates.

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Maze, KM, TB Koen e LA Watt. "Factors Influencing the Germination of Six Perennial Grasses of Central New South Wales". Australian Journal of Botany 41, n. 1 (1993): 79. http://dx.doi.org/10.1071/bt9930079.

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The effect of light, storage time, temperature regimes and water potential were examined on the germination of five native grasses of central New South Wales (Enteropogon ramosus, Bothriochloa macra, Elymus scabrus, Chloris truncata and Danthonia caespitosa), and one introduced grass (Eragrostis curvula). Caryopses of E. ramosus, B. macra and E. curvula reached maximum germination soon after harvest. The remaining species reached maximum germination after 6-10 months storage. For all species, except E. scabrus, the effect of light on germination changed with duration of storage and with the presence of the lemma and palea. The viability of naked caryopses was reduced more rapidly than the viability of caryopses stored with the lemma and palea intact, for all tested species; E. scabrus and E. curvula were not tested. E. scabrus, C. truncata, D. caespitosa and E. curvula had greater than 50% germination over a range of alternating temperatures. E. ramosus had the narrowest temperature range for good germination, exceeding 50% germination only at temperatures above 30/20*#176 (day/night). E. ramosus and E. curvula germinated over a wider range of water potential than the other species. The germination of D. caespitosa, B. macra and C. truncata fell significantly at a water potential of -0.1 MPa. It is concluded that temperature is likely to impede the germination of most of these grasses only in mid winter, and that soil water potential will probably have an overriding influence on the season of germination.

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Johnston, W. H., P. S. Cornish e V. F. Shoemark. "Eragrostis curvula (Schrad.) Nees. complex pastures in southern New South Wales, Australia: a comparison with Medicago sativa L. and Phalaris aquatica L. pastures under rotational grazing". Australian Journal of Experimental Agriculture 45, n. 4 (2005): 401. http://dx.doi.org/10.1071/ea03117.

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A grazing experiment conducted in Wagga Wagga (New South Wales) from September 1993 to September 1998 compared the productivity of pastures containing 3 palatable types of summer-active Eragrostis curvula complex, with pastures containing either Medicago sativa or Phalaris aquatica. Issues relating to the management of E. curvula pastures were also investigated. Herbage growth rates of the P. aquatica and M. sativa pastures were highest in winter and spring; E. curvula pastures were most productive in summer and autumn. Stocking rates equivalent to 30–40 dry sheep were carried by the pastures during their growing seasons. Throughout the study, the pastures were dominated by their respective sown perennial species, however, a suite of desirable and undesirable annual grasses and annual legumes usually contributed >20% of total herbage mass in spring. The P. aquatica pasture contained a higher proportion of weedy species than the other pastures, especially C4 grasses and broadleafed species, and towards the end of the experiment it was also invaded by several native perennial grasses. Overall, the wool yield from the M. sativa pasture was 0.5–1.0 kg/animal.year higher than the other pastures. Management to minimise herbage accumulation on the E. curvula pastures was a key issue, and provided that pastures were grazed heavily, this was achieved by the rotational grazing strategy used in the experiment. It was concluded that palatable varieties of E. curvula have a useful and complementary role as perennial pastures in southern Australia. By increasing herbage availability in summer and autumn, E. curvula may improve management flexibility for a wide range of pastures that are commonly grown on farms.

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Cervigni, Gerardo D. L., Norma Paniego, Silvina Pessino, Juan P. Selva, Marina Díaz, Germán Spangenberg e Viviana Echenique. "Gene expression in diplosporous and sexual Eragrostis curvula genotypes with differing ploidy levels". Plant Molecular Biology 67, n. 1-2 (3 marzo 2008): 11–23. http://dx.doi.org/10.1007/s11103-008-9305-9.

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24

Johnston, WH. "Palatability to sheep of the Eragrostis curvula complex. 1. Methods of assessing palatability". Australian Journal of Experimental Agriculture 28, n. 1 (1988): 41. http://dx.doi.org/10.1071/ea9880041.

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This paper evaluates a method of judging palatability to sheep of accessions of Eragrostu curvula. Scores of from 0 (not grazed) to 10 (completely grazed) are compared with measured herbage consumption and percentage consumption values on 5 occasions at Orange and on 3 occasions in each of 2 trials at Wagga Wagga, N.S.W. Allowing for differences in initial herbage availability, regressions of score ranks pooled over all assessments of the 3 trials explained 65, 62 and 66%, respectively, of the variation in leaf, stem and total herbage consumption ranks. Most of the variation in stem consumption, however, was due its availability rather than palatability. It was concluded that palatability could meaningfully be predicted from score ranks alone. Comparison of different observers' scores allocated after several grazings showed that observers were consistent in their ranking. The results demonstrate the usefulness and merits of the different methods of assessing palatability.

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25

Nakayama, Naoki, Jun Nishihiro, Yuichi Kayaba, Takashi Muranaka e Izumi Washitani. "Seed deposition of Eragrostis curvula, an invasive alien plant on a river floodplain". Ecological Research 22, n. 4 (5 ottobre 2006): 696–701. http://dx.doi.org/10.1007/s11284-006-0047-3.

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26

Nakayama, Naoki, Jun Nishihiro, Yuichi Kayaba, Takashi Muranaka e Izumi Washitani. "Seed deposition of Eragrostis curvula, an invasive alien plant on a river floodplain". Ecological Research 22, n. 4 (13 febbraio 2007): 702. http://dx.doi.org/10.1007/s11284-007-0346-3.

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27

Garbus, Ingrid, José Rodolfo Romero, Juan Pablo Selva, María Cielo Pasten, Carolina Chinestra, José Carballo, Diego Carlos Zappacosta e Viviana Echenique. "De novo transcriptome sequencing and assembly from apomictic and sexual Eragrostis curvula genotypes". PLOS ONE 12, n. 11 (1 novembre 2017): e0185595. http://dx.doi.org/10.1371/journal.pone.0185595.

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28

Gargano, A. O., M. A. Adúriz e M. C. Saldungaray. "Yield and quality of fertilized deferred forage of Digitaria eriantha and Eragrostis curvula". Journal of Arid Environments 47, n. 2 (febbraio 2001): 181–89. http://dx.doi.org/10.1006/jare.2000.0709.

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29

Lazarides, M. "A Revision of Eragrostis (Eragrostideae, Eleusininae, Poaceae) in Australia". Australian Systematic Botany 10, n. 1 (1997): 77. http://dx.doi.org/10.1071/sb96002.

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Based on characters of gross morphology, a taxonomic revision is presented of the Australian taxa of Eragrostis Wolf, comprising 69 endemic and exotic species distributed in six groups. Seventeen species are proposed as new. Ten taxa are hereby reduced to synonymy. Lectotypes are designated for 11 species. New distribution records include E. atrovirens for Australia, E. schultzii for Western Australia, E. leptocarpa and E. pergracilis for Victoria, E. minor for New South Wales, and E. sterilis for New South Wales and the Northern Territory. Polymorphy and interspecific gradation are inherent problems in the taxonomy of the genus. Also, apparent evolutionary characters such as mode of spikelet disarticulation can be inconsistent and difficult to interpret. Features of the caryopsis relating to 3-dimensional shapes, compression, surface markings, and an adnate or free pericarp are among the most useful characters for identification purposes. Cleistogamy occurs in many species, but is not reflected in spikelet morphology. Eragrostis curvula is recorded as an apomict.

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30

Carballo, Jose, Diego Zappacosta, Gianpiero Marconi, Jimena Gallardo, Marco Di Marsico, Cristian A. Gallo, Mario Caccamo, Emidio Albertini e Viviana Echenique. "Differential Methylation Patterns in Apomictic vs. Sexual Genotypes of the Diplosporous Grass Eragrostis curvula". Plants 10, n. 5 (10 maggio 2021): 946. http://dx.doi.org/10.3390/plants10050946.

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DNA methylation is an epigenetic mechanism by which a methyl group is added to a cytosine or an adenine. When located in a gene/regulatory sequence it may repress or de-repress genes, depending on the context and species. Eragrostis curvula is an apomictic grass in which facultative genotypes increases the frequency of sexual pistils triggered by epigenetic mechanisms. The aim of the present study was to look for correlations between the reproductive mode and specific methylated genes or genomic regions. To do so, plants with contrasting reproductive modes were investigated through MCSeEd (Methylation Context Sensitive Enzyme ddRad) showing higher levels of DNA methylation in apomictic genotypes. Moreover, an increased proportion of differentially methylated positions over the regulatory regions were observed, suggesting its possible role in regulation of gene expression. Interestingly, the methylation pathway was also found to be self-regulated since two of the main genes (ROS1 and ROS4), involved in de-methylation, were found differentially methylated between genotypes with different reproductive behavior. Moreover, this work allowed us to detect several genes regulated by methylation that were previously found as differentially expressed in the comparisons between apomictic and sexual genotypes, linking DNA methylation to differences in reproductive mode.

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31

Beltrán López, Sergio, Carlos Alberto García Díaz, Catarina Loredo Osti, Jorge Urrutia Morales, José Antonio Hernández Alatorre e Héctor Guillermo Gámez Vázquez. "“Llorón Imperial”, Eragrostis curvula (Schrad) Nees, variedad de pasto para zonas áridas y semiáridas". Revista Mexicana de Ciencias Pecuarias 9, n. 2 (28 marzo 2018): 400. http://dx.doi.org/10.22319/rmcp.v9i2.4532.

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El pasto Llorón (Eragrostis curvula) es una gramínea perenne, originaria de Sudáfrica, de buen valor forrajero, se adapta bien a una amplia gama de suelos y condiciones climáticas. La variedad Imperial proviene de colectas realizadas en el centro y norte de México. Fue evaluada en zonas áridas y semiáridas, en temporal y riego desde 1986 hasta la obtención del registro en el año 2008. El registro otorgado por el Servicio Nacional de Inspección y Certificación de Semillas (SNICS) es: ERA-001-060608. A la fecha, la primera variedad registrada para esta especie en México. El rendimiento medio anual por hectárea de esta variedad oscila entre 896 y 1,947 kg de materia seca (MS) en condiciones de temporal, con una media de 1,200 kg y entre 3,150 y 6,100 kg MS en condiciones de riego con una media de 4,070 kg MS. Esta variedad de pasto es tolerante a la sequía, de fácil establecimiento y de rápido crecimiento, además es apetecible para el ganado, resistente al pastoreo y tolerante a la salinidad. Es una especie utilizada para la recuperación de agostaderos degradados y conservación de suelo en pastizales de zonas áridas y semiáridas en México.

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32

Mynhardt, Jennifer E., M. W. van Rooyen e G. K. Theron. "Competitive ability of two grass species: Anthephora pubescens and Eragrostis curvula. 2. Growth analysis". South African Journal of Botany 60, n. 5 (ottobre 1994): 269–75. http://dx.doi.org/10.1016/s0254-6299(16)30602-0.

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33

Wan, Changgui, e Ronald E. Sosebee. "Tillering responses to red:far-red light ratio during different phenological stages in Eragrostis curvula". Environmental and Experimental Botany 40, n. 3 (dicembre 1998): 247–54. http://dx.doi.org/10.1016/s0098-8472(98)00044-6.

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34

Romero, J., J. P. Selva, S. Pessino, V. Echenique e I. Garbus. "Repetitive sequences in Eragrostis curvula cDNA EST libraries obtained from genotypes with different ploidy". Biologia plantarum 60, n. 1 (1 gennaio 2016): 55–67. http://dx.doi.org/10.1007/s10535-015-0569-z.

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35

Cardone, S., P. Polci, JP Selva, M. Mecchia, S. Pessino, P. Hermann, V. Cambi, P. Voigt, G. Spangenberg e V. Echenique. "Novel genotypes of the subtropical grass Eragrostis curvula for the study of apomixis (diplospory)". Euphytica 151, n. 2 (30 agosto 2006): 263–72. http://dx.doi.org/10.1007/s10681-006-9156-x.

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36

Roberts, Jason, Singarayer Florentine, Eddie van Etten e Christopher Turville. "Germination biology of four climatically varied populations of the invasive species African lovegrass (Eragrostis curvula)". Weed Science 69, n. 2 (12 gennaio 2021): 210–18. http://dx.doi.org/10.1017/wsc.2020.99.

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AbstractAfrican lovegrass [Eragrostis curvula (Schrad.) Nees] is a highly invasive C4 perennial grass that threatens global biodiversity. Appropriate management of this species has been hampered by a lack of knowledge concerning its seed ecology, resulting in significant economic and environmental impacts within various environments. Consequently, this study explored the effects of a selection of environmental factors (photoperiod, alternating temperature, pH, and salinity) by analyzing several measures of germination on four geographically distinct populations of E. curvula to assist in its extirpation from infested sites. Seeds were collected in Australia from Maffra and Shepparton, VIC; Tenterfield, NSW; and Midvale, WA. Key results showed that seeds from Maffra (54% vs. 79%), Tenterfield (38% vs. 61%), and Shepparton (34% vs. 71%) had significantly reduced germination in complete darkness compared with an alternating 12-h light and 12-h dark photoperiod, whereas Midvale had consistent germination (91% vs. 99%). Temperatures between 17/7 C reduced germination for Maffra (42% vs. 73%), Tenterfield (34% vs. 55%), and Shepparton (33% vs. 59%) compared with the mean of all other temperature combinations, whereas Midvale had consistent germination. Furthermore, germination for all populations was consistent between pH 4 and 9. For salinity, germination was significantly reduced at ≥100 mM for Maffra (29% vs. 67%), ≥150 mM for Tenterfield (29% vs. 94%) and Shepparton (39.5% vs. 81.5%), and 250 mM for Midvale (39% vs. 82%) compared with the mean of all other concentrations. Although each trial was conducted independently, the data can be used to generate species-targeted management. Such strategies include maintaining high levels of quarantine and hygiene programs to avoid future spread; where practical, applying light-limiting strategies (mulching, tilling, or scraping) for the Maffra, Tenterfield, and Shepparton populations; and maintaining management efforts year-round, as the species can germinate under a wide range of conditions.

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37

Mynhardt, Herman, Willem Adriaan Van Niekerk, Lourens Johannes Erasmus, Abubeker Hassen e Roelf Johannes Coertze. "Substitution of rumen degradable nitrogen with urea in sheep fed low quality Eragrostis curvula hay". Scientia Agricola 73, n. 6 (dicembre 2016): 498–504. http://dx.doi.org/10.1590/0103-9016-2015-0277.

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38

DI RENZO, M. A., M. A. IBAÑEZ, N. C. BONAMICO, M. E. FARICELLI, M. M. POVERENE e C. V. ECHENIQUE. "Effect of three environments on the efficiency of indirect selection in Eragrostis curvula (lovegrass) genotypes". Journal of Agricultural Science 140, n. 4 (giugno 2003): 427–33. http://dx.doi.org/10.1017/s0021859603003216.

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A significant genotype–environment interaction can limit gains in selecting superior genotypes since the best genotype in one locality may not be the best one in another locality. The efficiency of indirect selection is related to the heritability of the trait and to the genetic correlation between localities. Since a major objective of Eragrostis curvula (lovegrass) breeding programmes in Argentina is to select superior genotypes from new cultivar introductions, research on the relative effectiveness of direct and indirect selection is necessary in order to identify localities under which the efficiency of indirect selection could be maximized. To do this, experiments using a set of 18 hybrids were carried out in three localities from the semi-arid region of Argentina. Aerial biomass yield, leaf length, crown diameter, panicle number and panicle length were measured and an analysis of variance and covariance were performed. The high genetic correlation obtained suggests that the genetic mechanisms involved in the expression of these traits would be the same, or at least very similar, in Río Cuarto, Villa Mercedes and Bahía Blanca environments where the hybrids showed a stable performance. In general, the heritability obtained was higher in Villa Mercedes and Bahía Blanca than in Río Cuarto. For a given selection intensity the expected correlated response in Villa Mercedes and Bahía Blanca to indirect selection was compared with the expected gain with direct response to selection in Río Cuarto. For dry matter yield, indirect selection in Bahía Blanca did not differ from selection done in Río Cuarto (−3%). However, for performance in Villa Mercedes indirect selection was shown to be less efficient (−29%). For the other traits considered, indirect selection was variable and less efficient, ranging from −18 to −34%. The estimated decrease in efficiency of selection for all the traits considered in the locality of Río Cuarto was higher than in the other localities, suggesting that this place was not a good choice for carrying out indirect selection. Conversely, genetic progress would be faster if selection was carried out in Villa Mercedes, because the evaluations provide higher and more accurate estimates of the heritabilities than in the other localities.

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39

Wan, C. "Tiller recruitment and mortality in the dryland bunchgrass Eragrostis curvula as affected by defoliation intensity". Journal of Arid Environments 51, n. 4 (agosto 2002): 577–85. http://dx.doi.org/10.1016/s0140-1963(01)90939-5.

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40

Wan, Changgui, e Ronald E. Sosebee. "Tiller recruitment and mortality in the dryland bunchgrass Eragrostis curvula as affected by defoliation intensity". Journal of Arid Environments 51, n. 4 (agosto 2002): 577–85. http://dx.doi.org/10.1006/jare.2001.0939.

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41

Snyman, L. D. "Nutritive value of maize residues in comparison with Eragrostis curvula hay as feed for sheep". Animal Feed Science and Technology 34, n. 3-4 (settembre 1991): 213–27. http://dx.doi.org/10.1016/0377-8401(91)90112-6.

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42

Ncanana, Sandile, Wolf Brandt, George Lindsey e Jill Farrant. "Development of plant regeneration and transformation protocols for the desiccation-sensitive weeping lovegrass Eragrostis curvula". Plant Cell Reports 24, n. 6 (18 marzo 2005): 335–40. http://dx.doi.org/10.1007/s00299-005-0940-1.

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43

Johnston, WH. "Consol lovegrass (Eragrostis curvula complex) controls spiny burrgrass (Cenchrus spp.) in south-western New South Wales". Australian Journal of Experimental Agriculture 29, n. 1 (1989): 37. http://dx.doi.org/10.1071/ea9890037.

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Experiments established 30 km north and 30 km south of Urana N.S.W. in 1980 and 198 1, on areas heavily infested with spiny burrgrass, showed that lovegrass (Eragrostis curvula) varieties Consol and accession 4660 were more easily and reliably established than buffel grass or lucerne. Lovegrass persisted up to 1988 and continued to spread, despite 3 extremely dry summer periods and uncontrolled grazing. It achieved virtual control of spiny burrgrass after 4 years. Lucerne failed to persist in 3 out of 4 sowings, and only persisted where phosphorus had been applied. Lovegrass density was highest where fertiliser was not applied. Lovegrass can be recommended for controlling spiny burrgrass on infertile, sandy textured soils in low rainfall environments where the use of lucerne is uneconomic or its establishment and management are difficult.

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44

Robinson, GG, e RDB Whalley. "Competition among three agronomic types of the Eragrostis curvula (Schrad.) Nees complex and three temperate pasture grasses on the Northern Tablelands of New South Wales". Australian Journal of Agricultural Research 42, n. 2 (1991): 309. http://dx.doi.org/10.1071/ar9910309.

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Three agronomic types of the African lovegrass (Eragrostis cuwula (Schrad.) Nees) complex were established in a replacement series with three temperate pasture grasses to determine their relative competitiveness over three years in the field on the Northern Tablelands of New South Wales. The curvula agronomic type was more competitive than Consol or the chloromelas type which were similar in competitive ability. Festuca arundinacea Schreb., Dactylis glomerata L. and Pharlaris aquatica L. were each able to reduce the forage production of the curvula type in spring, but were in turn subject to suppression during summer and autumn. The relationships among Consol, the chloromelas type and the temperate grasses followed a similar pattern, but differences in their relative competitiveness were smaller. F. arundinacea was the most competitive of the temperate grasses, but this ability declined over time; D. glomerata was equally competitive during early assessments, but its ability declined more rapidly, while P. aquatica was the least successful competitor with any of the E. cuwula types. Differences in competitiveness among species over time (particularly the decline in competitiveness of the temperate species) suggest that management practices aimed at minimizing the impact of invasions by the E. cuwula complex should be investigated.

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45

Yagisawa, Junji, e Norio Tanaka. "Flood wash-out conditions of an exotic and invasive plant,Eragrostis curvula, in Arakawa River, Japan". International Journal of River Basin Management 8, n. 1 (marzo 2010): 15–24. http://dx.doi.org/10.1080/15715121003715057.

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46

Mynhardt, Jennifer E., M. W. van Rooyen e G. K. Theron. "Competitive ability of two grass species: Anthephora pubescens and Eragrostis curvula. 1. Yield and biomass allocation". South African Journal of Botany 60, n. 5 (ottobre 1994): 261–68. http://dx.doi.org/10.1016/s0254-6299(16)30601-9.

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47

Maze, KM, e MR Goodridge. "The effect of four broadleaf herbicides on seedlings of five native and one introduced grass species." Rangeland Journal 13, n. 2 (1991): 91. http://dx.doi.org/10.1071/rj9910091.

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The effect of four broadleaf herbicides (metsulfuron-methyl, bromoxynil + MCPA, chlorsulfuron and 2,4-D mine), on the growth of five native and one introduced grass species was tested on the seedling stage of each grass. The growth of Elymus scabrus, Chloris truncata and Eragrostis curvula was not affected by any of the herbicides used. Bromoxynil + MCPA appeared to be the least damaging of the herbicides on the growth of Bothriochloa macra, Danthonia caespitosa and Enteropogon ramosus, although the extent of damage caused varied between the species. Metsulfuron-methyl, chlorsulfuron and 2,4-D amine had detrimental effects on all three species. The variability of responses to broadleaf herbicides exhibited by the native grass species suggests that herbicide trials will be a necessary part of native grass domestication programs.

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48

Selva, Juan Pablo, Diego Zappacosta, José Carballo, Juan Manuel Rodrigo, Andrés Bellido, Cristian Andrés Gallo, Jimena Gallardo e Viviana Echenique. "Genes Modulating the Increase in Sexuality in the Facultative Diplosporous Grass Eragrostis curvula under Water Stress Conditions". Genes 11, n. 9 (21 agosto 2020): 969. http://dx.doi.org/10.3390/genes11090969.

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Eragrostis curvula presents mainly facultative genotypes that reproduce by diplosporous apomixis, retaining a percentage of sexual pistils that increase under drought and other stressful situations, indicating that some regulators activated by stress could be affecting the apomixis/sexual switch. Water stress experiments were performed in order to associate the increase in sexual embryo sacs with the differential expression of genes in a facultative apomictic cultivar using cytoembryology and RNA sequencing. The percentage of sexual embryo sacs increased from 4 to 24% and 501 out of the 201,011 transcripts were differentially expressed (DE) between control and stressed plants. DE transcripts were compared with previous transcriptomes where apomictic and sexual genotypes were contrasted. The results point as candidates to transcripts related to methylation, ubiquitination, hormone and signal transduction pathways, transcription regulation and cell wall biosynthesis, some acting as a general response to stress and some that are specific to the reproductive mode. We suggest that a DNA glycosylase EcROS1-like could be demethylating, thus de-repressing a gene or genes involved in the sexuality pathways. Many of the other DE transcripts could be part of a complex mechanism that regulates apomixis and sexuality in this grass, the ones in the intersection between control/stress and apo/sex being the strongest candidates.

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49

MA, Ruiz, AD Golberg e O. Mart韓ez. "Water stress and forage production in Tetrachne dregei Nees, Panicum coloratum L. and Eragrostis curvula (Schrad) Nees". Phyton 77, n. 1 (2008): 7–20. http://dx.doi.org/10.32604/phyton.2008.77.007.

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50

Meier, Mauro, Diego Zappacosta, Juan Pablo Selva, Silvina Pessino e Viviana Echenique. "Evaluation of different methods for assessing the reproductive mode of weeping lovegrass plants, Eragrostis curvula (Schrad.) Nees". Australian Journal of Botany 59, n. 3 (2011): 253. http://dx.doi.org/10.1071/bt10267.

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Weeping lovegrass is a forage grass cultivated in semiarid regions of the world that reproduces mainly by apomixis (diplospory), a process that involves the formation of asexual seeds and bypasses the processes of meiosis and fertilisation. The aim of this work was to evaluate and compare different techniques (cytoembryology, callose deposition, flow cytometry and progeny tests) to determine the reproductive mode of weeping lovegrass. Typical sexual and apomictic processes were clearly differentiated using cytoembryology, and different callose deposition patterns were observed in sexual and apomictic genotypes. Previous studies indicated that presence of callose on the cell wall of the megaspore mother cell is associated only with sexual processes. Nevertheless, our results also found callose deposition in apomictic genotypes, although clearly different from the pattern found in sexual processes, allowing discrimination between sexual and apomictic plants. Flow cytometry seed screening using individual seeds did not differentiate between sexual and apomictic plants as the embryo : endosperm DNA content ratio was similar in sexual and apomictic plants. Progeny tests using molecular markers showed uniform patterns in offspring from apomictic plants and variable patterns among the progeny of sexual plants. The results obtained from cytological studies and progeny tests were similar, indicating that both methods provide useful tools for determination of reproductive mode. However, the callose test with aniline blue was faster and easier to use than other techniques.

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