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Full-Text Articles in Plant Pathology
Seasonal Fluctuations Of Vegetative Storage Proteins And Starch Concentrations In Stolons Of Trifolium Repens L., V Bouchart, A Ourry, J C. Simon, J Boucaud
Seasonal Fluctuations Of Vegetative Storage Proteins And Starch Concentrations In Stolons Of Trifolium Repens L., V Bouchart, A Ourry, J C. Simon, J Boucaud
IGC Proceedings (1997-2023)
The seasonal pattern of nitrogen, starch and vegetative storage protein (VSP) concentrations was studied in the stolons of two Trifolium repens L. genotypes (cv Aran and Rivendel). Maximum concentrations of starch were found in summer months; its hydrolysis occurred in winter, at the time, where VSP and nitrogen were accumulated. The decrease of nitrogen and VSP concentrations occurred during spring, and an inverse relationship was found between VSP concentrations in stolons and mean temperatures. The causal implications of starch and VSP availability on spring regrowth potential are discussed in relation with regulatory mechanism inducing VSP synthesis.
Modelling The Effect Of A Variable Light Extinction Coefficient And Leaf Dispersion On Light Partitioning Between Species In A Grass-Clover Mixture, M Nassiri, A Elgersma
Modelling The Effect Of A Variable Light Extinction Coefficient And Leaf Dispersion On Light Partitioning Between Species In A Grass-Clover Mixture, M Nassiri, A Elgersma
IGC Proceedings (1997-2023)
Light partitioning in a grass-clover mixture was studied using a general competition model. The model assumes a fixed extinction coefficient (k) and no leaf dispersion. This was compared with modelling the effect of different k of both species over height as well as the effect of type of leaf dispersion. These new assumptions led to a better estimation of the light partitioning between both species. For grass the effect of variable k and leaf dispersion was similar and in both cases the total absorbed light was lower than under default conditions. For clover the new assumptions led to a higher …
Effect Of Lowered Light Quality (R:Fr Ratio) At Targeted Organs On Branching Of Trifolium Repens, M J.M Hay, Ch Robin, P C.D Newton, A Cresswell, J Tilbrook
Effect Of Lowered Light Quality (R:Fr Ratio) At Targeted Organs On Branching Of Trifolium Repens, M J.M Hay, Ch Robin, P C.D Newton, A Cresswell, J Tilbrook
IGC Proceedings (1997-2023)
This report examined results from four similarly conducted experiments using Trifolium repens in which the R:FR ratio but not the photosynthetically active radiation (PAR) of incident light was altered at specific organ(s) of several successive phytomers or just at a single phytomer. Results indicate the local response to lowered R:FR light treatment was similar irrespective of the number of phytomers treated. This response pattern provides the means whereby plants can initiate strong localised responses to a heterogeneous light environment.
Partitioning Of Phosphorus In White Clover Populations With Different Nodulation Patterns, J R. Crush
Partitioning Of Phosphorus In White Clover Populations With Different Nodulation Patterns, J R. Crush
IGC Proceedings (1997-2023)
The objective of this study was to see if a white clover (Trifolium repens L.) population selected for development of relatively few, but large nodules, differed in the way it used absorbed phosphorus, compared to a white clover population selected for many small nodules. Plants of both populations were grown in minus-nitrogen sand culture and the dry weights and phosphorus contents of shoots, roots and nodules were measured. There were no differences in growth or partitioning of dry matter or phosphorus between the clover lines.
Introduction Of Vegetative And Reproductive Characters Into Trifolium Repens By Interspecific Hybridisation, A H. Marshall, T P.T Michaelson-Yeates, M Meredith, D H. Hides
Introduction Of Vegetative And Reproductive Characters Into Trifolium Repens By Interspecific Hybridisation, A H. Marshall, T P.T Michaelson-Yeates, M Meredith, D H. Hides
IGC Proceedings (1997-2023)
Interspecific hybridization between white clover (Trifolium repens L.) and ball clover (T.nigrescens) and Caucasian clover (T.ambiguum) is a means of improving the reproductive growth and persistency of T.repens. F1 hybrids between T.repens and T.nigrescens were produced without ovule culture and confirmed as true hybrids by chromosome counts, isoenzyme analysis and leaf markers. Their growth habit was generally intermediate between the two parents. After backcrossing to T.repens the BC1 and BC2 hybrids had more of the characteristics associated with T.repens though they retained some of the greater reproductive growth of …
Selection For Herbage Yield And Flowering In Ladino White Clover, J A. Garcia
Selection For Herbage Yield And Flowering In Ladino White Clover, J A. Garcia
IGC Proceedings (1997-2023)
A geno-phenotypic recurrent selection program is being carried out on ladino white clover (Trifolium repens L.) aiming to combine good DM and seed yields. Selection criteria includes plant density, vigor, winter growth, flowering and diseases resistance. The performance of selections in terms of DM yields and seed production was evaluated in separate trials. Two cycles of selection increased flowering by 36% and seed yield by 59%. Preliminary data on herbage yields shows a very good performance of the selected material and suggests the feasibility of combining high DM and seed yields.
Evaluating White Clover For Resistance To Cylindrocladium Root Rot, D S. Wofford, A Amaya
Evaluating White Clover For Resistance To Cylindrocladium Root Rot, D S. Wofford, A Amaya
IGC Proceedings (1997-2023)
A rapid screening technique was developed for use in evaluating white clover (Trifolium repens L.) for resistance to Cylindrocladium root rot incited by Cylindrocladium crotalariae. Culture plates of the fungus were evaluated for number of infective propagules after four weeks of growth on potato dextrose agar, and no differences were detected among plates. Seedlings of ‘Osceola’ white clover were exposed in the greenhouse to four levels of inoculum over a six-week period, with resistance based on percent survival of uninoculated controls. It was shown that suspending 1 culture plate in 100ml of water and rating plants four weeks …
How Do Cattle And Sheep Alter Ingestive Behaviour In Response To Changes In Sward State?, P D. Penning, R J. Orr, A J. Parsons, A Harvey
How Do Cattle And Sheep Alter Ingestive Behaviour In Response To Changes In Sward State?, P D. Penning, R J. Orr, A J. Parsons, A Harvey
IGC Proceedings (1997-2023)
Ingestive behaviour of yearling Friesian heifers continuously stocked on monocultures of Lolium perenne (G) or Trifolium repens (C) maintained at sward heights of 7-8 cm, was recorded. Bite masses, prehension biting and mastication rates were similar between treatments (211 vs. 230 mg DM prehension bite-1, 61 vs. 55 prehension bites and 11 vs. 13 mastications, min-1 for G and C, respectively). DM intake rates were 12.9 g min-1 for both treatments. Animals grazed longer (536 vs.436 min) and ruminated longer (526 vs. 267 min-1) on G compared with C. Daily intakes were 6.9 vs.5.6 kg DM for G and C. …
Effects Of Fasting On Ingestive Behaviour Of Sheep Grazing Grass Or White Clover Monocultures, P D. Penning, M Boval
Effects Of Fasting On Ingestive Behaviour Of Sheep Grazing Grass Or White Clover Monocultures, P D. Penning, M Boval
IGC Proceedings (1997-2023)
Effects of fasting sheep for 24 h (F), compared with controls (NF), on their ingestive behaviour and particle size in extrusa was investigated using oesophageally fistulated animals, grazing monocultures of Lolium perenne (G) or Trifolium repens (C). Bite masses tended to be lower on G than C and tended to increase with fasting (40, 64, 61 and 70 mg DM bite-1) for treatments GNF, GF, CNF and CF, respectively. Prehension rate was lower (52 vs. 69 bites min-1) and masticating rate was higher (106 vs.86 mastications min- 1) for G and C treatments, respectively. Over 24 h following fasting, NF …
Performance Of Dairy Cows, Feed Quality And N Balance On Pasture Systems With Or Without Mineral N Fertilizer, M Rodehutscord, Ina Hahner, H Spiekers, E Pfeffer
Performance Of Dairy Cows, Feed Quality And N Balance On Pasture Systems With Or Without Mineral N Fertilizer, M Rodehutscord, Ina Hahner, H Spiekers, E Pfeffer
IGC Proceedings (1997-2023)
In a 2 year experiment, two levels of mineral N fertilization (nil and 225 kg N/ha) on pasture were checked for their effects on pasture yield and quality as well as for performance of dairy cows. Twenty six cows were used in each treatment and the stocking density was adapted to previous results on pasture growth rates. Cows were kept on pasture during summer and grass silages were harvested from the respective experimental areas for winter feeding periods. Digestibility of organic matter in these silages, determined in wether sheep, was always higher in those silages harvested from pasture without mineral …
Dry Matter Intake, Milk Performance And Production Efficiency From Spring Calving Dairy Cows Offered Grass-Only, Grass-White Clover And Total Mixed Ration Diets, E. Fitzpatrick, Luc Delaby, Trevor J. Gilliland, D. Hennessy
Dry Matter Intake, Milk Performance And Production Efficiency From Spring Calving Dairy Cows Offered Grass-Only, Grass-White Clover And Total Mixed Ration Diets, E. Fitzpatrick, Luc Delaby, Trevor J. Gilliland, D. Hennessy
IGC Proceedings (1997-2023)
In pasture-based dairy production systems, dry matter intake (DMI) is one of the main factors curtailing milk production and production efficiency. The inclusion of white clover (Trifolium repens L.) in swards of perennial ryegrass (PRG; Lolium perenne L.) can increase DMI from increased sward nutritive value over a grass-only sward. Feeding a fully balanced TMR diet can enhance milk production as a result of greater DMI and through greater control of feed quality. Therefore, the objective of this study was to determine the relationship between DMI, milk production, and energy efficiencies for dairy cows consuming different diets. A farm …
Seasonal Performance Of White Clover In Mixed-Sward Grazing Pasture Highlights Genotype By Environment Interaction, O. Grace Ehoche, Sai Krishna Arojju, Greig Cousins, Jessica O'Connor, Brian Maw, Jennifer A. Tate, Peter J. Lockhart, Mohamed Z. Z. Jahufer, Andrew G. Griffiths
Seasonal Performance Of White Clover In Mixed-Sward Grazing Pasture Highlights Genotype By Environment Interaction, O. Grace Ehoche, Sai Krishna Arojju, Greig Cousins, Jessica O'Connor, Brian Maw, Jennifer A. Tate, Peter J. Lockhart, Mohamed Z. Z. Jahufer, Andrew G. Griffiths
IGC Proceedings (1997-2023)
White clover is an important forage crop because of its nutritional value, ability to provide plantavailable nitrogen via symbiosis with Rhizobium soil bacteria, and year-round availability of dry matter (DM) yield. However, its performance in mixed sward-based pastures is characterised by seasonal variability and declining DM yield over time. The identification of white clover genotypes adapted for across seasonal performance is an important goal in white clover breeding. In this study, we evaluated the seasonal performance of 200 white clover half-sib families using visual growth scores and calibrated dry matter yield based on growth scores measured for three years in …