Plant Pathology Commons^™

Commercialisation And Impacts Of Pasture Legumes In Southern Australia–Lessons Learnt, Clinton K. Revell, Michael A. Ewing, Daniel Real, Phillip G. H. Nichols, Graeme A. Sandral

IGC Proceedings (1977-2023)

Forage legumes are a key feature of temperate grasslands in southern Australia, valued for their ability to increase animal production, improve soil fertility and fix atmospheric nitrogen. Of the 36 temperate annual legume and 11 temperate perennial legume species with registered cultivars introduced or domesticated in Australia over the last 100 years, a third have made a major contribution to agriculture, a third have modest use and a third have failed to make any commercial impact. Highly successful species include subterranean clover, barrel medic, white clover, lucerne, French serradella and balansa clover. Species were assessed on the scale of their …

Global Impact Of Sown Temperate Pastures On Productivity And Ecosystem Stability–What Progress Have We Made?, E. Charles Brummer

IGC Proceedings (1977-2023)

Twenty years ago, in 1993, we published one of the first two alfalfa genetic linkage maps. At the time, hopes ran high that genetic marker technologies would revolutionize selection, making the development of superior cultivars both easier and faster. The objective of this paper is to critically examine forage improvement since that time and to suggest ways to more fully capitalize on those initial hopes in the future. Marker studies have been conducted around the world, identifying quantitative trait loci (QTL) for the major agronomically important traits, including biomass yield, nutritive value, disease resistance, abiotic stress tolerance, and others. But …

Structural Characteristics Of Porto Rico Stargrass (Cynodon Nlemfuensis) Pastures Under Different Frequencies And Severities Of Defoliation, Carlos Augusto Brandão De Carvalho, Sergio Trabali Camargo Filho, Domingos Sávio Campos Paciullo, Pablo Giliard Zanella, Elisa Cristina Modesto, Priscila Beligoli Fernandes

IGC Proceedings (1977-2023)

An understanding of the effects of frequency and severity of defoliation on the sward structure of pastures is essential for identifying pasture management strategies that are more efficient in forage usage in tropical environments (Da Silva and Nascimento Jr 2007; Euclides et al. 2010). Some pasture species have not yet been investigated in this way, e.g. cultivars of Cynodon. The potential of this grass in tropical environments suggests that it should be given priority (Pedreira 2010). This study was designed to evaluate the effects of 2 frequencies (90 and 95% light interception) and severities (20 and 30 cm …

Effect Of Grazing Height On Marandu Pasture Production And Performance Of Soybean Grain-Supplemented Nellore Bulls, Andre L. S. Valente, Ricardo A. Reis, Sharadinny M. C. Dos Santos, Fernando H. M. De Souza, Telma T. Berchielli, Ana C. Ruggieri, Sabrina S. Santana, Juliana M. Serra

IGC Proceedings (1977-2023)

The Brazilian beef cattle industry is primarily based on the use of pastures. Grasses belonging to the genus Brachiaria are extremely important, regardless of whether the production system used is intensive or extensive.

Appropriate management of the system is vital for obtaining a high efficiency of resource usage. Adjustment of stocking rate to maintain optimum forage allowance and feeding of supplements are strategies for achieving these aims. Feeding of concentrates on pasture can result in increased carrying capacity and higher weight gains over unsupplemented systems.

The purpose of this study was to evaluate the effects of 3 different grazing heights …

Establishment Of Leucaena Leucocephala Cv. Tarramba In Eastern Indonesia, Jacob Nulik, H. Dahlanuddin, Debora Kana Hau, Charles Pakereng, Resti G. Edison, Dessy Liubana, S. P. Ara, Hayley E. Giles

IGC Proceedings (1977-2023)

The adaptability and productive value of Leucaena leucocephala cv. Tarramba (Tarramba) in eastern Indonesia has been observed since 2001 (Nulik et al. 2004), with many farmers and other stakeholders currently requesting seed for planting. Tarramba has greater forage and timber production, and psyllid tolerance than other commercial cultivars and locally grown leucaena. The variability of soils and climate in eastern Indonesia means that establishment techniques specific to the region are required to achieve maximum adoption and utilisation of Tarramba.

Potential Of Australian Bermudagrasses (Cynodon Spp.) For Pasture In Subtropical Australia, Andrew Hacker, Meena Puachuay, H. Max Shelton, Scott A. Dalzell, Haider Al Dabbagh, Margaret Jewell, Thinh Van Tran, The Ngo, Yi Zhou, Michael J. Halliday, Hayley E. Giles, Don S. Loch, Ian D. Godwin, Fukai Shu, Chris O’Brien, Will Pearce, William F. Anderson, Christopher J. Lambrides

IGC Proceedings (1977-2023)

In Australia, little work has been carried out on the improvement of tropical or subtropical pastures in recent years. There seems to be an increasing demand for pastures that can withstand heavy grazing, while producing high yields of high quality forage in the humid subtropical regions of Australia. Most graziers, who live in these areas, have small acreages, which they graze intensively. Cynodon spp. represent a potential source of grasses with these attributes. This study will evaluate the pasture potential of a large number of bermudagrass (Cynodon spp.) ecotypes collected from across Australia.

Selection Of Psyllid-Resistant Forage Varieties From An Inter-Specific Breeding Program Of Leucaena Leucocephala With L. Pallida, Scott A. Dalzell, Lachlan M. Robertson, Christopher J. Lambrides, James L. Brewbaker, Del Greenway, Mark Dieters, H. Max Shelton

IGC Proceedings (1977-2023)

Leucaena (Leucaena leucocephala) pastures for beef cattle production are productive and sustainable; however, susceptibility to the psyllid insect (Heteropsylla cubana) has limited expansion of current commercial cultivars into more humid areas (> 800 mm/yr) (Shelton and Dalzell 2007). Psyllids can also cause intermittent damage in lower rainfall regions during humid periods. The psyllid, which arrived in Australia in 1986, is a leaf-sucking insect specific to the Leucaena genus, feeding on the growing tips of susceptible cultivars (Bray 1994). Psyllid damage can reduce production by as much as 50-70% in humid regions and 20-50% in subhumid environments …

Growth Of Bali Bulls On Rations Containing Sesbania Grandiflora In Central Lombok, Indonesia, H. Dahlanuddin, Baiq Tutik Yuliana, Tanda Panjaitan, Michael J. Halliday, H. Max Shelton

IGC Proceedings (1977-2023)

The demand for meat in Indonesia is currently growing by up to 8% per year, with beef cattle fattening identified as a major livestock industry (Purwantara et al. 2012). Bali cattle (Bos javanicus) account for almost 27% of total beef cattle in Indonesia; they are the predominant breed in the eastern islands and are highly favoured by smallholder farmers for their high fertility, low calf mortality and generally higher price at markets (Purwantara et al. 2012). Lombok in west Nusa Tenggara is one of the biggest suppliers of Bali cattle in Indonesia.

A major constraint to …

Animal Performance And Productivity Of A New Cultivar Of Brachiaria Brizantha, Valéria P. B. Euclides, Denise B. Montagner, Cacilda B. Valle, Nayana N. Nantes

IGC Proceedings (1977-2023)

Brazil has the competitive advantage of a very dynamic and cost-effective animal production system on pastures over other countries. The pursuit of more productive forages that will result in higher quality beef at a lower cost is justified. As Brachiaria is the most important forage genus utilised in Brazil, an intense search for new cultivars amongst collected and introduced ecotypes from Africa is underway. Following agronomic evaluation of this material in plots, 8 Brachiaria ecotypes were pre-selected. As part of Embrapa`s process of cultivar development, B. brizantha cv. Xaraés, characterised by high productivity (liveweight gain/area), was released in 2003, followed …

Performance Of Young Nellore Bulls Grazing Marandu Grass Pasture At Different Heights, Ricardo A. Reis, Andre L. S. Valente, Sharadinny M. C. Dos Santos, Fernando H. M. De Souza, Telma T. Berchielli, Ana C. Ruggieri, Sabrina S. Santana, Juliana M. Serra

IGC Proceedings (1977-2023)

Brazil is one of the largest beef cattle producers in the world with approximately 200 M head. The Industry relies predominantly on warm-season grass pastures, with approximately 90% of animals finished on pastures.

One of the main factors for the intensification of animal production systems based on pasture is appropriate management. Adjustment of stocking rate to maintain optimum forage allowance is essential. Studies on forage allowance have resulted in a better understanding of the response of forage crops and animals to changes in grazing intensity.

The purpose of this study was to evaluate management strategies for beef cattle systems grazed …

Seasonal Expression Of Apospory In Bahiagrass, Esteban F. Rios, Ann R. Blount, Kevin E. Kenworthy, Carlos A. Acuña, Kenneth H. Quesenberry

IGC Proceedings (1977-2023)

Flowering plants can reproduce sexually (outcrossing and/or selfing) and/or asexually. Sexual reproduction implies the successful completion of meiosis and double fertilisation for the formation of both the embryo and the endosperm. In contrast, gametophytic apomixis is an asexual mode of reproduction through seeds that involves parthenogenetic embryo development from a cytologically unreduced egg cell (2n). Apospory is the process by which unreduced gametophytes are formed after a series of mitotic divisions of somatic cells (2n) in the ovary. This occurs independently from the sexual meiotic process; and therefore, both sexual and apomictic pathways may coexist simultaneously. Apospory is inherited in …

Morphogenic Responses Of Two Brachiaria Genotypes In Response To Clipping Frequency, Ana Flávia G. Faria, Carlos G. S. Pedreira, Diego N. L. Pequeno, Liliane S. Silva, Damião W. Nguluve, Aliedson S. Ferreira

IGC Proceedings (1977-2023)

Tropical grasslands represent an important resource for the Brazilian cattle industry, which is heavily dependent on grazed pastures. Total pasture area in the country totals 196 M ha (23% of the country’s land area) (FAO 2013). The genus Brachiaria represents around 85% of cultivated pastures in Brazil (Moreira et al. 2009), 40% of which are established with B. brizantha cv. Marandu (Barbosa 2006). Mulato II is a new hybrid brachiaria grass cultivar which has been developed to improve agronomic characteristics, broaden the range of adaptation, and to ensure high forage production and nutritive value. It has also been viewed …

Sward Structural Characteristics Of Perennial Peanut Genotypes As Affected By Harvest Frequency, Aliedson S. Ferreira, Carlos G. S. Pedreira, Carla M. Marassatto

IGC Proceedings (1977-2023)

Despite the high potential of tropical forage species, herbage production, nutritive value and animal productivity in Brazilian livestock production systems are lower than what can be obtained from both a biological and operational point of view (Pedreira and Mello 2000, Da Silva and Sbrissia 2000). Even with these limitations, the livestock industry is often able to sustain high productivity levels (animal product per hectare) by using good animal genetics and supplementation. Reducing production costs, however, will likely depend on the identification and incorporation of a high-quality forage resource, in terms of both improving diet quality of grazing animals and sustaining …

Morphophysiological Adaptations Of Brachiaria Humidicola Cultivars Under Grazing, Rodrigo A. Barbosa, Pedro N. C. Amaral, André F. Sbrissia, Thiago T. Camara

IGC Proceedings (1977-2023)

Pastures of Brachiaria humidicola are broadly used in Brazil, especially in soils with low fertility and poor drain-age (Valle et al. 2010). Currently, 3 cultivars are commercially available: Tully, Llanero and BRS Tupi (available since 2012). Despite the extensive use of this species, research has focused primarily on aspects related to herbage and animal production, while only a few studies aimed at understanding morphological adaptations of the plants when subjected to grazing and contrasting environmental conditions.

Therefore, the aim of this work was to evaluate some morphological traits of 2 B. humidicola cultivars when continuously stocked during 2 seasons …

Vegetative Propagation Of Stylosanthes Scabra, Alexandre C. L. De Mello, Adeneide C. Galdino, José C. B. Dubeux Jr., Mércia V. F. Dos Santos, Mário De A. Lira Jr., Felipe M. Saraiva, Mário De A. Lira, Márcio V. Da Cunha

IGC Proceedings (1977-2023)

One way to multiply genetically desirable plants in a more uniform manner is to use vegetative propagation, such as using plant cuttings. This technique multiplies a single plant into several, in an easy low-cost system (Fachinello et al. 2005), so it is useful in plant breeding. This technique may be enhanced through the use of hormonal regulators, with indolebutyric acid (IBA) being most frequently used, because of its stability in hydroalcoholic solution, low sensitivity to biological degradation and good establishment of adventitious roots (Fachinello et al. 1995). In spite of its large-scale use for fruit production, the technique …

Effects Of Two Intake Levels Of Leucaena Leucocephala On Rumen Function Of Sheep, Marcos Barros-Rodríguez, Javier Solorio-Sánchez, Carlos Sandoval-Castro, Athol V. Klieve, Eduardo Briceño-Poot, Luis Ramírez-Avilés, Rafael Rojas-Herrera

IGC Proceedings (1977-2023)

Ruminant production systems based on grass pastures often produce poor animal performance as expressed by growth or reproductive rates. The nutrient imbalance affecting rumen function is due to their low energy and protein intake. The incorporation of leguminous forages such as Leucaena leucocephala, in the diet of ruminants, can stimulate rumen function by providing protein-rich forage (Barros-Rodriguez et al. 2012). This increases the availability of compounds such as ammonia, amino acids and peptides as well as branched short-chain fatty acids, which are produced as a result of degradation of proteins. These substances promote fibre breakdown by acting as ruminal …

Survey Of Pasture Species And Management, Manure Management, Milk Production And Reproduction On Pasture-Based Dairy Farms In Florida And Georgia, Usa, F. Du, K. D. Gay, M. E. Sowerby, Y. C. Newman, C. R. Staples, R. C. Lacy, A. De Vries

IGC Proceedings (1977-2023)

Traditionally, most dairy farms in the south-eastern United States confine cows to barns or on pasture lots year-round and feed stored forages and concentrated feeds (Fontaneli et al. 2005). Often, much of the feed is purchased, however, the cost of purchased feed and fuel has risen rapidly in the last 5 years (NASS 2009). In addition, a significant amount of capital is tied up in buildings, machinery and manure management systems on the farms. For these reasons, many dairy farmers have shown an interest in or started transitioning to pasture-based dairy systems (Ricks and Hardee 2012). The management practices …

Breeding Strategies For Brachiaria Spp. To Improve Productivity–An Ongoing Project, Geovani F. Alves, Ulisses J. De Figueiredo, Antônio D. Pandolfi Filho, Sanzio C. L. Barrios, Cacilda B. Valle

IGC Proceedings (1977-2023)

Two strategies have been used in the breeding of Brachiaria (syn. Urochloa) to produce new cultivars. The first involves exploring the natural variability existing in nature, which is the selection of ecotypes, mostly apomicts, from the diversity in germplasm banks. This strategy proved efficient originally and the cultivars in use in Brazil were derived in this way, but progress with this strategy is limited in the medium to long term.

Dry Matter Intake By Beef Steers On Piatã Palisadegrass (Brachiaria Brizantha Cv. Brs Piatã) Pasture, Denise B. Montagner, Valéria P. B. Euclides, Teresa C. M. Genro, Nayana N. Nantes

IGC Proceedings (1977-2023)

Beef production in Brazil is primarily based on tropical pastures and 85% of these pastures are Brachiaria brizantha cv. Marandu. Such a monoculture could prove disastrous if some pest or disease emerged. With the goal of further diversifying pastures and contributing to the sustainability of the pasture production system, B. brizantha cv. BRS Piatã was released by the Brazilian Agricultural Research Corporation (Embrapa). Little is known about the characteristics of this cultivar in relation to grazing management and plant-animal interactions. Dry matter (DM) intake by grazing animals is influenced by the structural characteristics of tropical grasses (Stobbs 1973, 1975), and …

Agronomic Evaluation Of 324 Intraspecific Hybrids Of Brachiaria Decumbens In Brazil, Rogério G. Mateus, Sanzio C. L. Barrios, Ulisses J. De Figueiredo, Cacilda B. Valle

IGC Proceedings (1977-2023)

Brachiaria decumbens cv. Basilisk is the most planted pasture grass in the tropics owing to its adaptation to poor and acid soils, typical of the tropics, plus good animal performance. This cultivar was responsible for a radical change of scenario in central Brazil in the early 1970s and is the only cultivar available commercially. Efforts to breed this species have been recent, as the successful somatic chromosome duplication of sexually reproducing diploid plants of B. decumbens was accomplished only in 2009 (Simioni and Valle 2009). Subsequently, intraspecific crosses with natural apomictic tetraploid accessions were carried out. Breeding is needed since …