Physical Sciences and Mathematics Commons^™

Differential Responses Of Yield And Shoot Traits Of Five Tropical Grasses To N And Distance To Trees In Silvopastoral Systems, L. S. Pontes, Emilio A. Laca

IGC Proceedings (1997-2023)

Light intensity and nitrogen (N) availability are important factors influencing the growth of C₄ forage species. Trade-offs may occur in the adaptive responses of species to shading and N inputs, and functional shoot traits can help to explain the consequences of these responses for species performance. Our objective was to gain understanding of the mechanisms between traits of five C₄ perennial grasses determining above-ground dry matter yield (DMY) when both resources, light and N, vary. Forage grasses were grown in six shading conditions (full sunlight vs. five positions between Eucalyptus dunnii rows) with two N levels (0 vs. …

Addition Of Red Clover Or Birdsfoot Trefoil In Alfalfa-Based Mixtures To Improve The Forage Energy To Protein Balance, Philippe Seguin, Gaëtan F. Tremblay, M. Thériault, X. Godin, Shabtai Bittman, D. Hunt, J. Hakl, Gilles Bélanger, M.-N. Thivierge, Annick Bertrand, A. Claessens

IGC Proceedings (1997-2023)

The low ratio of sugars (S) to crude proteins (CP) in alfalfa (AL, Medicago sativa L.) leads to inefficient use of nitrogen by ruminants. The objective was to determine if adding red clover (RC, Trifolium pratense L.) or birdsfoot trefoil (BT, Lotus corniculatus L.) with or without a grass species to AL improved the forage S/CP ratio. Treatments were 100% AL (control) or AL-based mixtures with RC or BT in three proportions (75, 50, or 25% of seeded legumes) with either no grass or with timothy (Phleum pratense L.) or tall fescue (Schedonorus arundinaceus Schreb. Dumort.), resulting in …

Cool-Season Perennials And Stability In Year-Round Forage Production Systems, C. D. Teutsch

IGC Proceedings (1997-2023)

Changes in long-term climate normals have resulted in warmer and wetter summers and milder winters in the humid eastern United States. This will likely impact regional forage species adaptation in the long-term and varietal adaptation in the short term. Variety evaluation has been occurring at the University of Kentucky for almost 100 years. There are several considerations for selecting forage species and varieties including regional and local adaptation, productivity, distribution of growth, palatability, nutritive value, anti-quality factors, tolerance to stress, and persistence. Two of the most important criteria are long-term productivity and persistence under grazing, both of which are currently …

Comparison Of Compositional Changes In Multi-Species Grass/Legume Mixture Experiments Across Three Nordic Countries (Iceland, Sweden And Finland) Over Two Years, Caroline Brophy, Anne-Maj Gustavsson, A. Helgadottir, Oiva Nissinen, J. Connolly

IGC Proceedings (1997-2023)

A multi-site experiment was established at 39 sites across Europe, Australia and Canada within COST Action 852 to: (1) assess the benefits of grass/legume mixtures over monocultures, (2) test the stability of mixtures and (3) evaluate the consistency of the observed patterns over broad environmental gradients. This paper compares the results from 3 Nordic sites using the same plant species: Korpa Experimental Station in Iceland, Lapland Research Station in Finland and Piteå in Sweden to investigate if compositional changes in mixtures are consistent across the sites.

The Effect Of Npk Fertilisation On Structure And Species Composition Of Grasslands, Frantisek Hrabě, Jiří Skládanka

IGC Proceedings (1997-2023)

Long-term research into the effect of N+PK nutrition enables an objective evaluation of the trend and rate of succession and a prediction of changes including production development in permanent grassland (Hrabě et al., 1991). Former research (Hrabě & Halva, 1993) and evaluation within an eco-system concept (Rychnovská et al., 1994) demonstrated marked changes in the species composition of grass communities with the application of N+PK fertilisation that did not correspond to the sward type and site conditions.

The Effect Of Grazing On Rare And Common Grasses And Forbs In The Mediterranean Coastal Desert Of Egypt, A. El-Keblawy, A. Ramadan

IGC Proceedings (1997-2023)

Large parts of the rangelands in the Arab countries are either overgrazed or gradually deteriorating due to large numbers of livestock and unrestricted grazing (Assaeed, 1997). Protection of vegetation against grazing in desert environments has been suggested as a feasible approach to halting land degradation and rehabilitating rangelands (El-Keblawy, 2003). However, little is known about the response of different plant life forms and life cycles to grazing. The objectives of this study were to address this point and to test the response of rare and common forbs and grasses to protection against grazing.

Accumulation And Decomposition Rates And N, P And K Returned To The Soil By The Litter Of Tropical Legumes And Grasses, Gustavo Crespo, I. Rodríguez, M. F. Días, Sandra Lok

IGC Proceedings (1997-2023)

The return of plant nutrients through litter decomposition of legumes and grasses is important for the sustainability of grassland ecosystems (Sánchez et al., 1989). Therefore, the selection of species that produce high amounts of decomposable litter is important . The objective of the present work was to study the production and decomposition rates of litter from various legumes and grasses in Cuba.

Contribution Of Grasses To Soil Fertility And Improved Livelihoods, G. P. Ojha, B. K. Dhital

IGC Proceedings (1997-2023)

Vegetable farming is increasing in Nepal as it provides better economic returns than growing other crops, especially in areas that have easy access to markets. Vegetable farming demands intensive care and balanced supplies of nutrients. Therefore, farmers cultivate vegetables near their residence and because vegetable growing is more profitable, farmers allocate more resources, including organic manure, for its cultivation. In general, using more organic manure on vegetables means that less organic manure is available for non-vegetable crops and farms, unless alternative arrangements are made for producing more organic manure or manure of higher quality.

Variation Of Ldmc And Sla Relationship Between Growth Forms In Natural Grasslands, J. Viégas, P. Cruz, J. P. Theau, C. Jouany, P. Ansquer, R. Al Haj Khaled, O. Therond, M. Duru

IGC Proceedings (1997-2023)

In agro-ecological studies, there is a growing interest in measuring both leaf dry matter content (LDMC) and specific leaf area (SLA). This interest lies on the fact that leaf traits are linked to gradients of environmental factors and ecosystem functions. Working with three contrasting wild species, Garnier et al. (2001) proposed a model linking these two traits. The model shows a relatively simple non linear and negative correlation between LDMC and SLA. Nevertheless, none of the species used to build the model were grasses (GRA) or forb rosettes (ROS = i.e. dicotyledonous with large entire leaves and absence of …

Productive Longevity And Yield Quality Of Galega-Grass Swards, Aleksandr Adamovich

IGC Proceedings (1997-2023)

Fodder galega (Galega orientalis Lam.) is an early maturing, very productive perennial forage legume that fixes atmospheric nitrogen. Unlike other legumes, pure stands of fodder galega provide stable yields of green feed and seeds and do not thin out between the years. The symbiotic potential of fodder galega to grow in mixtures with grasses can be exploited to produce ecologically safe forage and animal products.

Differences Of Energy Density From Plant Species Found In Permanent Grassland Using The Cellulase Method In Comparison To The Crude Nutrient Method, Renate Bockholt, K. Friedel, F. Buske

IGC Proceedings (1997-2023)

If no special instructions have been given, the metabolic energy (MJ/kg DM) and the energy density (MJ NEL/kg DM) of grass samples are calculated by the agricultural test institute using a standard valuation formula as regards crude nutrients, crude fiber content, crude protein contents and crude ash. On the other hand, it is well known from feeding tests that permanent grassland grasses and herbs, which may be dominant under semi-intensive or extensive management, can have low digestibility and low energy density.

Effects Of Forage Species And Stage Of Maturity On In Situ Disappearance Of Organic Matter And Fibre Fractions, H. S. Hussein

IGC Proceedings (1997-2023)

Nutrient utilisation by ruminants is altered by the forage species and its maturity. Maturity is the major factor affecting forage morphology and quality. Forage quality is reduced with maturity due to a decrease in the leaf:stem ratio and an increase in fibre components (Ugherughe, 1986). Improving forage utilisation by ruminants depends on accurate measurements of their nutritive value by using in vitro and in situ methods. The objective of this study was to assess the nutritive value (i.e., extent of in situ disappearance of organic matter [OM], neutral detergent fibre [NDF], and acid detergent fibre [ADF]) of four grass species …

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

IGC Proceedings (1997-2023)

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 Blue Light On Leaf Growth And Plant Development In Two Morphologically Contrasted Perennial Ryegrass Genotypes: Cellular Basis And Ecological Implications, F. Gastal, A. Verdenal, P. Barre

IGC Proceedings (1997-2023)

Several major plant responses to competition for light are determined by responses to light signals, in particular to red/far-red ratio (R/FR) and blue light, besides responses mediated through photosynthesis and carbon assimilation (Gautier et al., 1999). These responses to light signals allow plants to react to the presence of neighbours and to anticipate the impact of light competition on photosynthesis. The objective of the study was to evaluate the impact of blue light on leaf growth and its cellular basis, on two short and long leaved populations (FC and FL respectively), which were shown to have different competitive ability …

Application Of Molecular Technologies In Forage Plant Breeding, K. F. Smith, J. W. Forster, M. P. Dobrowolski, N. O. I. Cogan, N. R. Bannan, E. Van Zijll De Jong, M Emmerling, G. C. Spangenberg

IGC Proceedings (1997-2023)

Key points

1. A range of molecular breeding technologies have been developed for forage plant species including both transgenic and non-transgenic methodologies.
2. The application of these technologies has the potential to greatly increase the range of genetic variation that is available for incorporation into breeding programs and subsequent delivery to producers in the form of improved germplasm.
3. Further developments in detailing the phenotypic effect of genes and alleles both through research in target species and through inference from results from model species will further refine the delivery of new forage cultivars.

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

IGC Proceedings (1997-2023)

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.