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Full-Text Articles in Plant Pathology

Effects Of Method Of Renovation And Rate Of Nitrogen On Naturalized Pastures In Atlantic Canada, H T. Kunelius, M R. Carter Jun 2024

Effects Of Method Of Renovation And Rate Of Nitrogen On Naturalized Pastures In Atlantic Canada, H T. Kunelius, M R. Carter

IGC Proceedings (1977-2023)

Pastures in Atlantic Canada require periodic rejuvenation to maintain productivity. The effects of method of pasture renovation, soil loosening by paraplowing and nitrogen rates on naturalized pastures were determined. Both direct drilling and cultivation and sowing Lolium perenne L. and Trifolium repens L. in naturalized pastures increased the yields slightly and proportion of white clover. Loosening the soil by paraplowing tended to reduce the yields of naturalized swards. Nitrogen concentration and digestibility of dry matter were greatest in sown pastures.


Grass-Legume Mixtures Under Grazing, R D. Amendola Massiotti, C Garcia Alvarez, J Juarez Ramirez Jun 2024

Grass-Legume Mixtures Under Grazing, R D. Amendola Massiotti, C Garcia Alvarez, J Juarez Ramirez

IGC Proceedings (1977-2023)

Nine grass-legume mixtures were evaluated during their first year. A factorial experiment was carried out using a complete block design. Herbage on offer and residual herbage were estimated allowing calculation of net herbage production, herbage accumulation rate and grazing efficiency. The mixture of alfalfa (Medicago sativa L.) and orchard grass (Dactylis glomerata L.) with a net herbage production of 22 407 kg dry matter (DM) per ha outyielded white clover (Trifolium repens L.) mixtures. Substitution of alfalfa by white clover in the mixtures resulted in reduction of herbage accumulation rate by 19 kg DM ha-1 day-1 . …


White Clover Versus Nitrogen Fertilizer 2. Sheep Production, J.P J. Erens, K B. Miller, R J. Lucas, J.G. H. White, H S. Easton Jun 2024

White Clover Versus Nitrogen Fertilizer 2. Sheep Production, J.P J. Erens, K B. Miller, R J. Lucas, J.G. H. White, H S. Easton

IGC Proceedings (1977-2023)

Animal production on pasture systems provided with either fertiliser or biological nitrogen was compared. A grazing experiment was sown at AgResearch Gore (46°07’ S; 168°54’ E) in October, 1989. Four ryegrass/white clover paddocks were compared to four ryegrass paddocks, with the latter receiving 270 kg nitrogen/ha/year. Each paddock of 0.5 ha was subdivided for rotational grazing at 20 ewes/ ha. In comparison to the ryegrass pastures, mixed pastures produced 22% more herbage and were subsequently 22% higher stocked, lamb liveweight gains were 12% higher during lactation and 42% higher after weaning resulting in earlier sale at higher carcass weights. Ewe …


Mineral Contents Of White Clover Grass And Nitrogen Fertilized Grass Pastures For Lambs, R Sormunen-Cristian, P Nykänen-Kurki, J Peltola Jun 2024

Mineral Contents Of White Clover Grass And Nitrogen Fertilized Grass Pastures For Lambs, R Sormunen-Cristian, P Nykänen-Kurki, J Peltola

IGC Proceedings (1977-2023)

The mineral contents (Ca, P, Mg, K, Na, Fe, Cu, Zn, and Mn) of white clover grass without nitrogen and grass-only pastures with annual nitrogen rates of 0, 120 and 250 kg ha-1 were studied in 1994 and 1995. The pastures were grazed twice per season by growing lambs. The white clover contents averaged 25% and 42%, respectively. The Ca and Mg contents and the Ca/P ratio were higher, and the K/(Ca+Mg) equivalent ratio lower in white clover grass than in grass-only swards. The P content of white clover grass was similar to that of grass, and the K content …


Effect Of Species Horizontal Distribution On Defoliation Of Ryegrass-Clover Swards Grazed By Sheep, P C. De Faccio Carvalho, F Louault, M Lafarge Mar 2024

Effect Of Species Horizontal Distribution On Defoliation Of Ryegrass-Clover Swards Grazed By Sheep, P C. De Faccio Carvalho, F Louault, M Lafarge

IGC Proceedings (1977-2023)

Defoliation events on labelled white clover (Trifolium repens) growing points or ryegrass (Lolium perenne) tillers were measured during grazing tests by sheep with swards consisting of mixed ryegrass-clover (MIX) or alternate strips of clover and ryegrass (STRIP). Sward surface height was maintained at 6.4 cm by lawnmower cuts in order to obtain a similar surface height for both species. On average, during 13 grazing tests in STRIP and 11 in MIX swards, clover was the more defoliated species : 23.3% of the growing points in STRIP and 26.5% in MIX swards were defoliated compared to 16.2% …


A Multivariate Assessment Of Variation Within And Among Ladino White Clover Ecotypes, P Annicchiarico, E Piano Feb 2024

A Multivariate Assessment Of Variation Within And Among Ladino White Clover Ecotypes, P Annicchiarico, E Piano

IGC Proceedings (1977-2023)

Some 285 Ladino white clover genotypes selected from four ecotypes were multiplied clonally and evaluated in a replicated pot experiment over one year. Multivariate patterns of variation were depicted by principal component analysis performed on the correlation matrix of five morphophysiological traits, namely petiole length, central leaflet size, head production, number of florets per head and stolon density. Selection was based on high broad sense heritability values of all of these traits. The level of intra-population variation was so high relative to inter-population variation that almost all plant types possibe could be found within each ecotype, although at a variable …


Extensive Management Of Sheep Grazing In Upland Sown Grassland: Long-Term Effects On Plant Species Composition, C. A. Marriott, G. T. Barthram, T. G. Common, J. H. Griffiths, J. M. Fisher, K. Hood Aug 2023

Extensive Management Of Sheep Grazing In Upland Sown Grassland: Long-Term Effects On Plant Species Composition, C. A. Marriott, G. T. Barthram, T. G. Common, J. H. Griffiths, J. M. Fisher, K. Hood

IGC Proceedings (1977-2023)

Changes in the Common Agricultural Policy have led to the development of agri-environment schemes to deliver environmental goods from grasslands. These schemes encourage more extensive grazing systems, and change the emphasis from animal output to issues such as increasing biodiversity. Lower stocking densities are expected to promote the development of a heterogeneous habitat and associated compositional changes in plant species. The long-term effect of more extensive sheep management, combining cessation of fertiliser and lower grazing intensity, on botanical composition and animal output in upland sown grassland has been studied at 3 sites (Marriott et al., 2002) since 1990. We …


The Interaction Of Management With Botanical Composition Of Irrigated Grass-Legume Pasture Mixtures In The Intermountain West Usa, J. W. Macadam, T. C. Griggs, G. J. Mileski Jun 2023

The Interaction Of Management With Botanical Composition Of Irrigated Grass-Legume Pasture Mixtures In The Intermountain West Usa, J. W. Macadam, T. C. Griggs, G. J. Mileski

IGC Proceedings (1977-2023)

Beef produced on semi-arid range and milk produced in confinement are the main agricultural commodities in the semi-arid western USA. The studies reported here were undertaken to determine the suitability of irrigated pasture as an alternative to traditional beef and dairy production systems. The clipping and grazing studies were not run concurrently or within the same field, but were successive steps in selecting mixtures best-suited for rotational stocking of irrigated pastures in the Intermountain West. Summaries of productivity data have been reported elsewhere (MacAdam, 2002; MacAdam et al., 2004).


Reduce Tall Fescue Toxicosis In Festuca Arundinacea Forage Systems With Legumes, J. C. Waller, A. E. Fisher, H. A. Fribourg, C. J. Richards Jun 2023

Reduce Tall Fescue Toxicosis In Festuca Arundinacea Forage Systems With Legumes, J. C. Waller, A. E. Fisher, H. A. Fribourg, C. J. Richards

IGC Proceedings (1977-2023)

Tall fescue (Lolium arundinaceum = Festuca arundinacea) is an important cool-season grass because of persistence and spring and autumn productivity. Most existing tall fescue pastures in Tennessee are Kentucky-31 (KY-31) and are infested with the endophytic fungus Neotyphodium coenophialum that causes tall fescue toxicosis. Symptoms in beef cattle include reduced rates of gain, poor conception rates, decreased dry matter intake, a long rough haircoat in summer, and very low serum prolactin. Earlier studies indicated that the performance of cattle grazing endophyte-free (EF) tall fescue is superior to that of cattle grazing endophyte-infected (EI) tall fescue (Fribourg et al …


Quantitative Trait Locus Analysis Of Morphogenetic And Developmental Traits In An Ssr And Aflp-Based Genetic Map Of White Clover (Trifolium Repens L.), M. T. Abberton, N. O. I. Cogan, K. F. Smith, G. Kearney, A. H. Marshall, A. Williams, T. P. T. Michaelson-Yeates, C. Bowen, E. S. Jones, A. C. Vecchies, J. W. Forster Apr 2023

Quantitative Trait Locus Analysis Of Morphogenetic And Developmental Traits In An Ssr And Aflp-Based Genetic Map Of White Clover (Trifolium Repens L.), M. T. Abberton, N. O. I. Cogan, K. F. Smith, G. Kearney, A. H. Marshall, A. Williams, T. P. T. Michaelson-Yeates, C. Bowen, E. S. Jones, A. C. Vecchies, J. W. Forster

IGC Proceedings (1977-2023)

Molecular marker-assisted plant breeding is a key target for the temperate legume pasture crop white clover (Trifolium repens L.). The first genetic linkage map of white clover has been constructed using self-fertile mutants to derive an intercross based fourth and fifth generation inbred parental genotypes (F2[I.4R x I.5J]). The framework map was constructed using simple sequence repeat (TRSSR) and amplified fragment length polymorphism (AFLP) markers. Eighteen linkage groups (LG) corresponding to the anticipated 16 chromosomes of white clover (2n = 4x = 32), with a total map length of 825 cM were derived from a total of …


Quantitative Trait Locus Analysis Of Morphogenetic And Developmental Traits In An Ssr And Aflp-Based Genetic Map Of White Clover (Trifolium Repens L.), M. T. Abberton, N. O. I. Cogan, K. F. Smith, G. Kearney, A. H. Marshall, A. Williams, T. P. T. Michaelson-Yeates, C. Bowen, E. S. Jones, A. C. Vecchies, J. W. Forster Mar 2023

Quantitative Trait Locus Analysis Of Morphogenetic And Developmental Traits In An Ssr And Aflp-Based Genetic Map Of White Clover (Trifolium Repens L.), M. T. Abberton, N. O. I. Cogan, K. F. Smith, G. Kearney, A. H. Marshall, A. Williams, T. P. T. Michaelson-Yeates, C. Bowen, E. S. Jones, A. C. Vecchies, J. W. Forster

IGC Proceedings (1977-2023)

Molecular marker-assisted plant breeding is a key target for the temperate legume pasture crop white clover (Trifolium repens L.). The first genetic linkage map of white clover has been constructed using self-fertile mutants to derive an intercross based fourth and fifth generation inbred parental genotypes (F2[I.4R x I.5J]). The framework map was constructed using simple sequence repeat (TRSSR) and amplified fragment length polymorphism (AFLP) markers. Eighteen linkage groups (LG) corresponding to the anticipated 16 chromosomes of white clover (2n = 4x = 32), with a total map length of 825 cM were derived from a total of …


Productivity Of Winter And Spring Native Improved Vegetation Under Different Grazing Stocking Rates On Basaltic Soil, M. Bemhaja Jan 2022

Productivity Of Winter And Spring Native Improved Vegetation Under Different Grazing Stocking Rates On Basaltic Soil, M. Bemhaja

IGC Proceedings (1977-2023)

Improved grassland with Lotus corniculatus, Trifolium repens and annual phosphorus fertilization, was evaluated during winter and spring for five consecutive years under grazing at three different stocking rates on medium basaltic soil. Specific contribution of Lotus and Trifolium reached 67% of grassland community in the first year. Stipa setigera and Poa lanigera increased their contribution from 0.8 to 17% in the fourth year of grazing experiment. Highest average value of crude protein was 19% during the second year and was related to legumes contribution. Forage availability was always up to 1.5 ton MS/ha at the three stocking treatments. Average daily …


Pasture Dynamics After Sodseeding Cool Season Species With Or Without Glyphosate In Subtropical Natural Grasslands, Luciana M. Rizo, E. L. Moojen, Fernando L. F. De Quadros, F. E. Schlick, F. L. Correa Dec 2021

Pasture Dynamics After Sodseeding Cool Season Species With Or Without Glyphosate In Subtropical Natural Grasslands, Luciana M. Rizo, E. L. Moojen, Fernando L. F. De Quadros, F. E. Schlick, F. L. Correa

IGC Proceedings (1977-2023)

This trial was conducted to evaluate vegetation dynamics of natural grasslands fertilized and sodseeded with the cool season species Italian ryegrass (Lolium multiflorum), white clover (Trifolium repens) and birdsfoot trefoil (Lotus corniculatus) with or without glyphosate. Treatments that included herbicide spraying on natural vegetation caused a substitution of perennial grasses by undesirable species, and did not show a significant contribution of introduced species. Andropogon lateralis, Paspalum notatum, Paspalum dilatatum and Paspalum plicatulum almost disappeared, and were replaced by Chaptalia nutans and Apium spp, among others.


Orchardgrass Pastures For Early-Weaned Beef Calves, J. C. Waller, H. A. Fribourg, C. Dixon, A. E. Fisher, B. V. Conger Dec 2021

Orchardgrass Pastures For Early-Weaned Beef Calves, J. C. Waller, H. A. Fribourg, C. Dixon, A. E. Fisher, B. V. Conger

IGC Proceedings (1977-2023)

Orchardgrass (Dactylis glomerata) grown alone or with ladino white (Trifolium repens) and red (T. pratense) clovers, provides a high quality March to June pasture. However, many beef producers have their cows calving in January-March, thus producing offspring that are too young to utilize spring forage well. As an alternative, some producers have their cows bred so that calves are born in autumn (September-November). By spring, these calves are old enough to consume pasture forage. The few earlier studies on early weaning of fall-born calves consist of drylot feeding of high quality hay or concentrates. …


Effects Of Fertilizer Rates And Pasture Type On Soil Mineral Nitrogen Concentration Under Dairy Pasture, T. A. Cox, D. F. Chapman, Frank R. Mckenzie Sep 2021

Effects Of Fertilizer Rates And Pasture Type On Soil Mineral Nitrogen Concentration Under Dairy Pasture, T. A. Cox, D. F. Chapman, Frank R. Mckenzie

IGC Proceedings (1977-2023)

The effects of three rates of nitrogen (N) fertilizer applied to monocultures of perennial ryegrass (Lolium perenne L.) and white clover (Trifolium repens L.), and mixed ryegrass / clover swards, grazed by dairy cows on soil mineral nitrogen levels in the top 10cm of soil were studied on a dryland pasture in south-western, Victoria, Australia. Ammonium and nitrate were monitored for 14 months. Clover monocultures had significantly greater NO3- levels, however a similar trend was not observed for NH4+ . Increasing fertilizer application rate significantly increased both NO3- and NH4+ …


Defoliation And Water Deficit: Their Influence On Pasture Growth And Water Use Of White Clover, F. H. Santiñaque Aug 2021

Defoliation And Water Deficit: Their Influence On Pasture Growth And Water Use Of White Clover, F. H. Santiñaque

IGC Proceedings (1977-2023)

With the objective of understanding the physiological basis of defoliation and water use relationships of white clover (Trifolium repens L.) pastures during water deficits, an experiment in controlled conditions was carried out. Outdoors nine liters pots were filled with a loam-clay soil with a water content at field capacity (FC), of 35%(w/w), at a bulk density of 1.1 g/cm3. Pre-germinated and inoculated clover seeds were transplanted, and the number of plants was adjusted to permit the development of full plant cover. The level of P in the soil did not limit plant establishment or growth. The …


Lamb Growth On Leaf Turnips, White Clover And Pasture In Summer, C. L. Lindsay, Peter D. Kemp, Paul R. Kenyon, Stephen T. Morris, A. J. Wall Nov 2020

Lamb Growth On Leaf Turnips, White Clover And Pasture In Summer, C. L. Lindsay, Peter D. Kemp, Paul R. Kenyon, Stephen T. Morris, A. J. Wall

IGC Proceedings (1977-2023)

No abstract provided.


Effects Of Herbage Species On The Spatial Heterogeneity Of Biomass In Grazed Pasture: Kentucky Bluegrass Vs. White Clover, M. Tsutsumi, M. Fukasawa, N. Tachi, S. Itano, T. Kosako, H. Tsukada Oct 2020

Effects Of Herbage Species On The Spatial Heterogeneity Of Biomass In Grazed Pasture: Kentucky Bluegrass Vs. White Clover, M. Tsutsumi, M. Fukasawa, N. Tachi, S. Itano, T. Kosako, H. Tsukada

IGC Proceedings (1977-2023)

No abstract provided.


Phosphate Uptake By White Clover (Trifolium Repens L.) Genotypes With Contrasting Nodal Root Morphology, James R. Crush, L. Ouyang Jul 2020

Phosphate Uptake By White Clover (Trifolium Repens L.) Genotypes With Contrasting Nodal Root Morphology, James R. Crush, L. Ouyang

IGC Proceedings (1977-2023)

No abstract provided.


Seasonal Influence On Botanical Composition Of Plantain, Chicory, White- And Red-Clover Based Herbage Mixes, Sharini Carol Somasiri, Paul R. Kenyon, Peter D. Kemp, Patrick C. H. Morel, Stephen T. Morris Feb 2020

Seasonal Influence On Botanical Composition Of Plantain, Chicory, White- And Red-Clover Based Herbage Mixes, Sharini Carol Somasiri, Paul R. Kenyon, Peter D. Kemp, Patrick C. H. Morel, Stephen T. Morris

IGC Proceedings (1977-2023)

Use of herb based sward mixes that are productive in different weather conditions could be an effective option to provide feed requirements for finishing lambs year round compared to ryegrass (Lolium perenne L.)/white clover (Trifolium repens L.) sward in New Zealand (Kemp et al., 2010). Herbs such as plantain (Plantago lanceolata L.) and chicory (Cichorium intybus L.) and the legumes such as white clover and red clover (Trifolium pratense L.) as pure swards are known to improve lamb performance compared to ryegrass/white clover. Therefore, there is scope to have …


White Clover Seed Production Response To Irrigation, Ana L. Pereira, Ariel Pimienta, Pamela Aguirre, Marita Ferriso, Virginia Pravia Dec 2019

White Clover Seed Production Response To Irrigation, Ana L. Pereira, Ariel Pimienta, Pamela Aguirre, Marita Ferriso, Virginia Pravia

IGC Proceedings (1977-2023)

White clover is more sensitive to soil water restriction compared to other perennial legumes, due to its shallow root system and poor stomatal control. Its undetermined growth is influenced by soil water content and seed production is reduced when vegetative growth is not restricted through irrigation management. Restricting the amount of soil available water during the bloom stage reduced plant vegetative growth and increases seed production (Clifford, 1986). In Uruguay, there is not a defined rainy season, and annual average ranges between 1100 and 1300mm. However, due to higher water demand during late spring and summer, a water deficit period …


Widening The Adaptation Of White Clover By Incorporation Of Valuable New Traits From Wild Clover Species, Warren M. Williams, Isabelle M. Verry, Syed Wajid Hussain, H. A. Ansari, K. H. Widdup, N. W. Ellison, Shirley N. Nichols Dec 2019

Widening The Adaptation Of White Clover By Incorporation Of Valuable New Traits From Wild Clover Species, Warren M. Williams, Isabelle M. Verry, Syed Wajid Hussain, H. A. Ansari, K. H. Widdup, N. W. Ellison, Shirley N. Nichols

IGC Proceedings (1977-2023)

Although white clover (Trifolium repens) is the most widely used legume in grazed pastures of temperate and sub-tropical regions, it is severely restricted in genetic diversity for adaptive traits to low soil fertility and other stress environments, including drought. The objective of this research was to transfer traits for wider adaptation from other clover species by hybridisation. Eight Trifolium species with contrasting adaptations were shown by DNA sequence phylogenetics to be closely related to white clover. Interspecific hybridisation was undertaken among these species using embryo rescue, and an array of partially fertile F1 hybrids was obtained. Population development …


Improved Drought Stress Tolerance Of White Clover Through Hybridisation With Trifolium Uniflorum L., Shirley N. Nichols, Rainer W. Hofmann, Isabelle M. Verry Nov 2019

Improved Drought Stress Tolerance Of White Clover Through Hybridisation With Trifolium Uniflorum L., Shirley N. Nichols, Rainer W. Hofmann, Isabelle M. Verry

IGC Proceedings (1977-2023)

The objective of this study was to determine the effect of hybridisation with Trifolium uniflorum L. on drought resistance of Trifolium repens L. (white clover). Shoot dry weight of backcross 1 (BC1) hybrids was reduced less by water stress than for backcross 2 (BC2) hybrids and white clover, as were key morphological traits such as leaf area. Under water stress, important differences for the BC1 generation compared to white clover also included lower senescence, higher stolon density, increased root dry weight, and a higher maximum nodal root diameter. Drought decreased the net photosynthetic rate by up to 48% in BC2 …