Plant Pathology Commons^™

Factors Affecting Italian Ryegrass (Lolium Multiflorum L.) Seed Distribution, R. D. Williams, P. W. Bartholomew

IGC Proceedings (1977-2023)

Italian ryegrass (Lolium multiflorum L.) can be a productive and high-quality cool-season forage in the Southern Great Plains of the U.S.A, if it is managed to produce sufficient seed for effective reestablishment without compromising forage yield. Before the re-seeding dynamics of Italian ryegrass can be modeled an understanding of seed production, seed-shed, and seed dispersal is necessary. Here two factors affecting Italian ryegrass seed dispersal and distribution are examined – wind and cultivation practice (mowing and raking).

Practical Application Of A One-Parameter Approach To Assess The Accuracy Of Two Different Estimates Of Diet Composition In Sheep, C. Elwert, M. Rodehutscord

IGC Proceedings (1977-2023)

The composition of ingested herbage mixtures can be estimated using the alkane technique (Dove & Moore, 1995). Until now, the accuracy of the estimates is assessed by linear regression of estimated and actual proportions of the dietary components. The authors presented an approach to compare actual and estimated diet compositions using only one parameter named Distance (D; Elwert & Rodehutscord, 2005), thus enabling a statement regarding the similarity of estimated and known diet composition. In a feeding trial with sheep, diet composition was estimated using two different levels of information. The accuracy of the two estimates was assessed and compared …

Use Of Alkanes To Estimate Dry Matter Intake Of Beef Steers Grazing High Quality Pastures, G. Scaglia, H. T. Boland, I. Lopez-Guerrero, R. K. Shanklin, J. P. Fontenot

IGC Proceedings (1977-2023)

Pastures remain the most important source of nutrients for ruminant livestock and nutrition is critical to optimize animal production. The daily quantity of dry matter that is consumed by an animal is a critical measurement to make nutritional inferences about feed and subsequent animal response. Researchers are facing the dilemma that, while estimates of individual animal performance are readily obtained, it is still difficult to estimate the herbage intake of individual animals. The objectives of this experiment were to estimate forage intake in beef steers grazing tall fescue (Festuca arundinacea Schreb.) and alfalfa (Medicago sativa)/tall fescue pastures …

Effects Of Rumen Fill On Intake And Milk Production In Dairy Cows Fed Perennial Ryegrass, A. V. Chaves, A. Boudon

IGC Proceedings (1977-2023)

Physical limitation often limits dry matter intake (DMI) of high producing cows or cows fed high forage diets. The extent to which DMI is regulated by distention in the rumen depends upon the cow’s energy requirement and filling effects of the diet offered (Allen, 2000). The objective here was to challenge middle lactation dairy cows with rumen fill (rumen inert bulk – RIB) feeding ryegrass fresh cut (indoors) or grazed to determine whether RIB affects intake and milk production.

Objectives And Benefits Of Molecular Breeding In Forage Species, T. Lübberstedt

IGC Proceedings (1977-2023)

1. The amount of resources and information provided by forage crop genomic programs has dramatically increased during the past few years.
2. Trait-based forward genetic procedures such as mapping and expression profiling have successfully provided new candidate genes or genome regions affecting forage quality. Respective information can easily be transferred across related forage species.
3. Since several genes in major biochemical pathways related to forage traits have been isolated, gene-based reverse genetic approaches (transformation, association studies) are promising.
4. Most genetic experiments are conducted under simplified "artificial" conditions such as on single-spaced plants. Therefore, transferability of respective genetic information to breeding practice needs to …

Both Grass Development Stage And Grazing Management Influence Milk Terpene Content, G. Tornambé, A. Cornu, N. Kondjoyan, P. Pradel, M. Petit, B. Martin

IGC Proceedings (1977-2023)

Terpenes are a wide group of molecules originating from plants’ secondary metabolism. Forage terpenes vary according to the botanical composition and in particular to the proportion of plants such as Apiaceae, Lamiaceae or Asteraceae. These molecules are considered effective milk markers for the presence of diversified forages in dairy cow diets. The variation in terpene content in the milk of grazing cows would depend on the period of development of terpene-rich plants and on the grazing management, whereby cows do or do not have the opportunity to choose and to modify the botanical composition of the ingested grass. The aim …

Supplementation Under Intensive Grazing, Silage- Or Grain-Based Diets For Beef Production On Steer Performance And Meat Fatty Acid Composition, J. Martínez Ferrer, E. Ustarroz, C. G. Ferrayoli, A. R. Castillo, D. Alomar

IGC Proceedings (1977-2023)

Alfalfa (Medicago sativa L.) is the main cultivated pasture in Argentina. In beef production enhanced productivity and profit depend on high stocking rates and pasture utilisation, with grain supplementation necessary to maintain high individual live weight gains (LWG) and to increase production per ha (Ustarroz, 1999). Substitution of grazed grass by concentrate can affect meat fatty acid (FA) composition (French et al., 2000). The objective of this study was to evaluate the effects of intensifying an alfalfa-based grazing system and two confinement dietary regimens for beef steer finishing on animal performance and meat FA composition.

Sphingolipid Long-Chain Base Signaling In Compatible And Non-Compatible Plant–Pathogen Interactions In Arabidopsis, Mariana Saucedo-García, Ariadna González-Solís, Priscila Rodríguez-Mejía, Guadalupe Lozano-Rosas, Teresa De Jesús Olivera-Flores, Laura Carmona-Salazar, A. Arturo Guevara-García, Edgar B. Cahoon, Marina Gavilanes-Ruíz

Center for Plant Science Innovation: Faculty Publications

The chemical diversity of sphingolipids in plants allows the assignment of specific roles to special molecular species. These roles include NaCl receptors for glycosylinositolphosphoceramides or second messengers for long-chain bases (LCBs), free or in their acylated forms. Such signaling function has been associated with plant immunity, with an apparent connection to mitogen-activated protein kinase 6 (MPK6) and reactive oxygen species (ROS). This work used in planta assays with mutants and fumonisin B1 (FB1) to generate varying levels of endogenous sphingolipids. This was complemented with in planta pathogenicity tests using virulent and avirulent Pseudomonas syringae strains. Our results indicate that the …

Potential Yield Of Cocksfoot (Dactylis Glomerata) Monocultures In Response To Irrigation And Nitrogen, A. Mills, D. J. Moot, R. L. Lucas, P. D. Jamieson, B. A. Mckenzie

IGC Proceedings (1977-2023)

Cocksfoot is a widely sown grass in temperate pastures. However, while potential yield of cocksfoot can exceed 28 t DM/ha per year, it is often restricted by water, temperature and nitrogen (N). Of these, Peri et al. (2002) showed that N was severely limiting in all seasons. The aim of this study was to confirm the potential yield of cocksfoot and quantify the extent of yield reductions due to environmental constraints.

Diverse Forage Mixtures Effect On Herbage Yield, Sward Composition, And Dairy Cattle Performance, M. A. Sanderson, K. Soder, N. Brzezinski, S. Goslee, H. Skinner, M. Wachendorf, F. Taube, L. Muller

IGC Proceedings (1977-2023)

Managing complex mixtures of plants to take advantage of spatial and temporal variability in land and climate may be one ecological approach to increase productivity of pastures. We tested the hypothesis that complex mixtures of forage species would yield more herbage and reduce weed competition compared with a simple grass-legume mixture in grazed pastures.

Hygienic Value And Mycotoxins Level Of Grass Silage In Bales For Horses, A. Potkański, J. Grajewski, K. Raczkowska-Werwińska, B. Miklaszewska, A. Gubała, M. Selwet, M. Szumacher-Strabel

IGC Proceedings (1977-2023)

Mycotoxins are secondary metabolites of moulds which have adverse effects on humans, animals, and crops and result in illnesses and economic losses. The toxins may occur in storage under conditions favourable for the growth of the toxin-producing fungus or fungi. The highest forage concentration of toxins was found in horizontal storage methods such as bunker silos and feed piles, which were left open to oxygen. In any fermentation storage system, temperature and the presence of moisture is sufficient for toxin production. In a plastic covered storage system, oxygen penetration is slowed but not eliminated. The longer silage is stored, the …

Participatory Approach To Common Use Grazing Management In Dry Area Developing Countries, J. Tiedeman, A. Larbi, F. Ghassali, N. Battikha

IGC Proceedings (1977-2023)

Key points

1. Range restoration technology is available but useless when not followed by management.

2. Institutional mechanisms for grazing management are needed for communal range.

3. Community participatory approaches help pastoralists better manage rangeland grazing.

The Effects Of Maize And Whole Crop Wheat Silages And Quality Of Grass Silage On The Performance Of Lactating Dairy Cows, D. C. Patterson, D. J. Kilpatrick

IGC Proceedings (1977-2023)

Patterson et al. (2004) obtained positive milk production responses to the inclusion of maize silage in grass silage-based diets under Northern Ireland conditions. By contrast, while inclusion of fermented whole crop wheat increased total forage intake, it had no significant effect on milk production of dairy cows. More recently, a newer technique has been developed of harvesting the wheat crop at high DM content, with milling of the grain during harvesting and treatment with an urea/urease mixture at ensiling (alkalage treatment). The aim of the present study was to investigate the milk production potential of high DM whole crop …

Polyphenol Oxidase Activity And In Vitro Proteolytic Inhibition In Grasses, J. M. Marita, R. D. Hatfield, G. E. Brink

IGC Proceedings (1977-2023)

Harvesting and storing high quality forage in the cool humid regions remains a challenge due to the potential for protein degradation during ensiling. Red clover is an exception as high protein levels are maintained during ensiling. Decreased proteolytic activity in red clover is due to polyphenol oxidase (PPO) activity and appropriate o-diphenol substrates (Jones et al., 1995, Sullivan et al., 2004). This project was undertaken to determine if PPO activity is present in a range of grasses and the potential role in proteolytic inhibition in the presence of the o-diphenol caffeic acid.

The Effect Of Dry Matter Content And Inoculation With Lactic Acid Bacteria On The Residual Water Soluble Carbohydrate Content Of Silages Prepared From A High Sugar Grass Cultivar, D. R. Davies, D. K. Leemans, E. L. Bakewell, R. J. Merry

IGC Proceedings (1977-2023)

The introduction of new perennial ryegrass cultivars bred for high water soluble carbohydrate (WSC) content has created opportunities for improving the quality of grass silage, by not only providing adequate WSC for a good fermentation, but also sufficient to leave a higher residual level of WSC in the mature silage. High WSC silages have the potential to provide readily available energy during the early stages of rumen fermentation to balance energy and nitrogen supply and optimise rumen microbial growth. (Merry et al. 2002). The aim was to examine the effect of wilting and silage inoculants on the residual WSC content …

Using The Red Clover Polyphenol Oxidase Gene To Inhibit Proteolytic Activity In Lucerne, R. D. Hatfield, M. L. Sullivan, R. E. Muck

IGC Proceedings (1977-2023)

Preserving high quality forage in cool humid regions of agricultural production remains a challenge due to potentially high levels of protein degradation during ensiling. Red clover is an exception maintaining its high protein levels during ensiling. Decreased proteolytic activity in red clover is due to polyphenol oxidase (PPO) activity and appropriate o-diphenol substrates (Jones et al., 1995, Sullivan et al., 2004). This work highlights potential strategies for utilising PPO as a means of decreasing proteolytic degradation during the ensiling of lucerne and other forages.

New Results On Inhibition Of Clostridia Development In Silages, E. Kaiser, K. Weiß, I. Polip

IGC Proceedings (1977-2023)

The prevention of clostridial activity in silages is one of the most important aims in silage making. Clostridial activity in silages is especially expressed as the occurrence of butyric acid and as increased content of clostridial spores. A rapid reduction in the pH value at the beginning of fermentation process is considered as the most important factor for inhibition of clostridial development. It is assumed, that, if the “critical pH value” will be quickly achieved, clostridial activity in silages can be stopped. In experiments concerning the fermentation process it was found that the effect of acidification and dry matter content …

Ensilability And Silage Quality Of Different Cocksfoot Varieties, U. Wyss

IGC Proceedings (1977-2023)

Various factors determine the ensilability of plant crops. In addition to dry matter content, sugar and protein content, buffering capacity, plant structure, soil contaminations and epiphytic microflora are also important. In Switzerland, various mixtures and also pure swards are continuously revised on the basis of results from variety testing programs. The main parameters for these tests are the yield and nutrient contents. However, in terms of ensilability and silage quality, no systematic tests have been carried out. For this reason, we have tested the ensilability of different cocksfoot varieties as well as the quality of the silages.

Effects Of Silage Preparation And Microbial Silage Additives On Biogas Production From Whole Crop Maize Silage, M. Neureiter, C. Perez Lopez, H. Pichler, R. Kirchmayr, R. Braun

IGC Proceedings (1977-2023)

Biogas applications based on the production of energy from renewable resources have emerged in the past years due to several countries setting quotas for bioenergy thus promoting anaerobic digestion for heat and electricity generation. Maize is one of the most common substrates for biogas production based on energy crops because of the high yields per hectare with ensiling as the preferred method for storage. Experiments were performed to investigate whether conditions during the silage fermentation and the addition of starter cultures can affect the biogas yields.

Ensiling Characteristics Of Sudangrass Silage Treated With Green Tea Leaf Waste Or Green Tea Polyphenols, M. Kondo, K. Kita, H. Yokota

IGC Proceedings (1977-2023)

Green tea waste (GTW), emitted from beverage companies manufacturing tea drinks, contains high crude protein (CP) and polyphenols. Kondo et al. (2004) showed that GTW addition to forage ensiling enhanced lactic acid fermentation and decreased pH value. Ishihara et al. (2001) showed that high counts of Lactobacillus species were maintained and the counts of clostridia were decreased in the intestinal microflora of animals fed the diet containing green tea polyphenols (GTP). It is hypothesised that GTP might activate lactic acid bacteria and enhance silage fermentation. This study was conducted to evaluate the potential of GTW and GTP as silage …