Physical Sciences and Mathematics Commons^™

Animal Production From New Panicum Maximum Genotypes In The Amazon Biome, Brazil, Carlos M. S. De Andrade, Luis H. E. Farinatti, Hemython L. B. Do Nascimento, Andressa De Q. Abreu, Liana Jank, Giselle M. L. De Assis

IGC Proceedings (1993-2023)

The Panicum maximum breeding program coordinated by the Brazilian Agricultural Research Corporation - Embrapa has been evaluating and selecting genotypes under different soil and climatic conditions, with the objective to release new cultivars adapted to the diverse regions of Brazil. For the Amazon biome, small-plot experiments carried out in Acre between 2003 and 2005 allowed the selection of some promising genotypes (Valentim and Andrade 2005; Valentim et al. 2006; Andrade and Valentim 2009), with higher potential for forage growth than cultivars on the market. The objective of this work was to compare 2 new P. maximum genotypes with cv. …

Tropical Grass Growth Functions Modeling By Using Nonlinear Mixed Models, A. Hernández Garay, H. Vaquera Huerta, M. Calzada Marín, E. Ortega Jiménez, J. F. Enríquez Quiroz

IGC Proceedings (1993-2023)

Nonlinear Growth curves are used for modeling plant physiological variables. These models are preferable because the polynomial coefficients of the equations have a biological significance. The response variables of the curves occurs commonly with repeated measurements over time and measurements are on different environments. The traditional statistical analysis does not include a repeated measures approach, which can lead to improper estimation of the error terms. It is important to study the growth of tropical grass (Da Silva and Carvalho 2005).

Herbage Accumulation, Nutritive Value And Persistence Of Mulato Ii In Florida, Joao M. B. Vendramini, Lynn E. Sollenberger, Graham C. Lamb, Maria L. Silveira

IGC Proceedings (1993-2023)

Grasses in the Brachiaria genus are the most widely grown forages in tropical America, occupying over 80 Mha (Boddey et al. 2004). Mulato II is apomictic and a vigorous, semi-erect cultivar resulting from 3 generations of crosses including original crosses between ruzigrass and signal-grass (cv. Basilisk, apomictic tetrapliod). According to Peters et al. (2003), Mulato produced 25% more herbage mass than palisadegrass (Brachiaria brizantha) and koroni-viagrass (Brachiaria humidicola) under similar management practices. Although Mulato II shows promise as a forage in tropical regions, herbage accumulation and persistence in subtropical areas is unknown. This publication …

Agronomic And Nutritional Evaluation Of Intraspecific Crosses In Brachiaria Decumbens, Simony A. Mendonça, Sanzio C. L. Barrios, Ulisses J. De Figueiredo, Geovani F. Alves, Cacilda B. Valle

IGC Proceedings (1993-2023)

Brachiaria decumbens cv. Basilisk is the single most important forage grass used for pastures in the tropics. This cultivar has exceptional adaptation to acid soils, vigorous growth, ease of establishment, and good forage value throughout the year, but these favourable characteristics are counteracted by its susceptibility to insect pests such as spittlebug. Breeding to produce improved cultivars within this species was impossible until 2009 due to the lack of compatible sexual ecotypes. With the success of somatic chromosome duplication of sexually reproducing diploid plants of B. decumbens (Simioni and Valle 2009), intraspecific crosses with natural apomictic tetraploid accessions were finally …

Reciprocal Recurrent Selection In The Breeding Of Brachiaria Decumbens, Sanzio C. L. Barrios, Cacilda B. Valle, Geovani F. Alves, Rosangela M. Simeão, Liana Jank

IGC Proceedings (1993-2023)

Pastures of Brachiaria decumbens cv. Basilisk radically changed the scenario of livestock production in central Brazil in the early 1970s and in fact, promoted the development of this vast region. However, despite the reasonable biomass yields and nutritional value when grown on these tropical acid soils, its susceptibility to grassland spittlebugs has limited its use. The breeding of B. decumbens in Brazil has been restricted to interspecific crosses using cv. Basilisk as a pollen donor due to the lack of compatible sexual ecotypes within this species. Recently, the successful chromosome duplication of a sexually reproducing diploid accession produced 3 successful …

ProgardesTm: A Legume For Tropical/Subtropical Semi-Arid Clay Soils, Christopher Gardiner, Nick Kempe, Iain Hannah, Jim Mcdonald

IGC Proceedings (1993-2023)

The range of available sown pasture legumes for the vast heavy clay soil regions of northern Australia has long been regarded as being deficient (Burt 1993; Jones and Clem 1997; Pengelly and Conway 2000). Indeed immense areas of northern Australia’s semi-arid clay soil regions have no sown pasture legume with proven adaptation and persistence through the long annual dry seasons (Gardiner and Swan 2008). The genus Desmanthus is a Mimosaceae legume containing some 24 species which are native to the Americas and range from being herbaceous to suffruticose in habit (Luckow 1993). Desmanthus is one of the very few legumes …

Potential Of Panicum Maximum As A Source Of Energy, Liana Jank, Edson A. De Lima, Rosangela M. Simeão, Ronimar C. Andrade

IGC Proceedings (1993-2023)

The use of plant biomass as a source of energy presents many advantages, mainly that it is a renewable, clean source of energy. Many tropical grasses have excellent po-tential as energy crops. The main one in Brazil is Pennisetum purpureum (elephant grass) owing to its very high yields. However, it is vegetatively propagated, thus more difficult to establish than seed propagated species. The use of Panicum maximum (guinea grass) is a possible alternative for use as a source of energy, due to its high yields as well as seed propagation. The objective of this research was to evaluate the potential …

Quality Seed Production Of Range Grasses--A Major Constraint In Revitalising Tropical Pastures, D. R. Malaviya, D. Vijay, Chandan Kumar Gupta, Ajoy K. Roy, P. Kaushal

IGC Proceedings (1993-2023)

Only 4% of India’s geographical area of 326.82 M ha is under pastures. Socioeconomic and ecological consequ-ences of land degradation are affecting 85 M ha of rangelands/grasslands. To provide sufficient milk for the ever-growing population, current milk production of 128 M t must increase to 160 M t by 2020. To make this possible, an additional 825 M t of green fodder is required. Increasing the area producing green fodder is difficult because of severe competition from food crops. Revitalising the denuded grasslands is the most plausible means for improving the availability of green fodder. This needs mission mode programs …

Status Of Animal Feed Resources In Rwanda, M. Mutimura, A. B. Lussa, J. Mutabazi, C. B. Myambi, R. A. Cyamweshi, C. Ebong

IGC Proceedings (1993-2023)

Animal feed resources remain a major constraint for livestock development in tropical Africa. In Rwanda, grazing lands are shrinking sharply because crop cultivation is progressively encroaching on grazing areas with increasing human pressure (Mutimura and Everson 2011). Therefore, over 60% of households cultivating less than 0.7 ha, and owning livestock, practise zero-grazing, where farmers cut-and-carry forage and crop residues to feed animals that are kept exclusively under sheds (MINAGRI 2009). In general, the main feed for dairy cattle under a zero-grazing system is Napier grass (Pennisetum purpureum). For more than a decade, efforts to improve the feed resource …

Effect Of Cutting Interval On Yield And Quality Of Two Panicum Maximum Cultivars In Thailand, Michael D. Hare, Supaphan Phengphet, Theerachai Songsiri, Naddakorn Sutin, Eduardo Stern

IGC Proceedings (1993-2023)

Tanzania guinea grass [Panicum maximum cv. Tanzania (cv. Purple in Thailand)] has been grown in Thailand for over 20 years and has proven to be a high quality forage (Phaikaew et al. 2007). Mombasa guinea grass (Panicum maximum cv. Mombasa) was introduced to Thailand in 2007 and commercial seed production commenced in 2008 because of a demand for seed in central and South America (Hare et al. 2013). It is a larger and taller cultivar than Tanzania. A series of studies have been undertaken at Ubon Ratchathani University, Thailand, to study the agronomic differences between these …

Effect Of Cutting Interval On Yield And Quality Of Three Brachiaria Hybrids In Thailand, Michael D. Hare, Supaphan Phengphet, Theerachai Songsiri, Naddakorn Sutin, Eduardo Stern

IGC Proceedings (1993-2023)

In field trials in Thailand, Brachiaria hybrid cv. Mulato II produced significantly more green leaf, particularly during the dry season, than other brachiaria grasses (Hare et al. 2009). Cultivar Cayman produced more dry matter (DM) than Mulato II in one out of 3 wet seasons, and line BRO2/1794 produced similar DM yields to Mulato II (Pi-zarro et al. 2013).

The objective of this field study was to determine the effects of varying cutting intervals on growth and forage quality of hybrid brachiaria grasses in Thailand on infertile soils.

Brachiaria Hybrids: Potential, Forage Use And Seed Yield, Esteban A. Pizarro, Michael D. Hare, Mpenzi Mutimura, Changjun Bai

IGC Proceedings (1993-2023)

A brachiaria breeding program initiated in 1988 at CIAT (Centro Internacional de Agricultura Tropical) combined desirable attributes found in accessions of Brachiaria brizantha and B. decumbens. Three apomictic hybrids have been released (cvs. Mulato, Mulato II and Cayman). Mulato showed agronomic potential but seed yields were low. Trials in Central America demonstrated the superiority of Mulato II, a vigorous grass with very deep and branched roots, giving it excellent drought resistance in the Brazilian Cerrado and Mexico. Mulato II has excellent nutritional value. Following trials in Mexico and Thailand, evaluating 155 new hybrids for 7 years, cv. Cayman was …

Molecular Genetic Variability, Population Structure And Mating System In Tropical Forages, Melissa Garcia, Bianca B. Z. Vigna, Adna C. B. Sousa, Letícia Jungmann, Fernanda W. Cidade, Guilherme Toledo-Silva, Patricia M. Francisco, Lucimara Chiari, Marcelo A. Carvalho, Claudio T. Karia, Fabio G. Faleiro, Rodolfo Godoy, M. Dall’Agnol, Sueli S. Pagliarini, Francisco H. D. Souza, Tatiana T. Souza-Chies, Liana Jank, Rosangela M. S. Resende, Cacilda B. Valle, Maria I. Zucchi, Anete P. Souza

IGC Proceedings (1993-2023)

Microsatellite (SSR) markers were developed for the following tropical forage species, using accessions available from the plant genetic resources (PGR) collections held by EMBRAPA (Brazilian Agricultural Research Corporation): Brachiaria brizantha, B. humidicola, Panicum maximum, Paspalum spp., Stylosanthes capitata, S. guianensis, S. macrocephala, Calopogonium mucunoides and Centrosema spp. The markers were used to analyse population structure and genetic diversity, evolution and origin of the genetic variability in the centre of origin, mating systems and genetic resources in EMBRAPA’s germplasm bank. The results shed light on the amount of genetic variation within and between populations, revealed …

Leucaena Toxicity: A New Perspective On The Most Widely Used Forage Tree Legume, Michael J. Halliday, Jagadish Padmanabha, Chris S. Mcsweeney, Graham L. Kerven, H. Max Shelton

IGC Proceedings (1993-2023)

The tree legume Leucaena leucocephala (leucaena) is a high quality ruminant feed, vitally important for livestock production in the tropics despite the presence of mimosine in the leaves. This toxic non-protein amino acid has the potential to limit productivity and adversely affect the health of animals. The discovery and subsequent distribution in Australia of the ruminal bacterium Synergistes jonesii as an oral inoculum was shown in the 1980s to overcome these toxic effects. However, recent surveys of the status of toxicity worldwide; improved understanding of the chemistry and mode of action of the toxins; new techniques for molecular sequencing; and …

Global Impacts From Improved Tropical Forages: A Meta-Analysis Revealing Overlooked Benefits And Costs, Evolving Values And New Priorities, Douglas S. White, Michael Peters, Peter Horne

IGC Proceedings (1993-2023)

The wider use and improved performance of planted tropical forages can substantially change social, economic and environmental landscapes. By reviewing impact-related studies published in the past two decades, this paper shows how evolving development priorities have influenced the types of impacts being documented. A meta-analysis was used to examine 98 studies according to: (1) breadth of reported effects, as related to development goals of social equity, economic growth and environmental sustainability; (2) extent of effects, ranging from intermediate to longer-term impacts; and (3) measurement precision (identification, description and quantification). Impacts have been assessed for fewer than half of the documented …

Cellular Causes For Leaf Elongation Reductions Under Salinity In Panicum Coloratum, Leandro Cáceres, Edith Taleisnik

IGC Proceedings (1993-2023)

Soil salinity is a growing constraint to crop and forage production worldwide and has driven the quest for salt-tolerant germplasm. Perennial forage grasses are regarded as choice alternative for the productive use of saline areas as well as for mitigating salinity in these areas (Ridley and Pannell 2005). Panicum coloratum L. is a C4 perennial grass native to tropical Africa, adapted to a wide range of rainfall conditions which makes it attractive as a forage for semiarid areas (Jones 1985). In forage grasses, yield is directly related to leaf area expansion and duration and the purpose of this work was …

Response Of Axonopus Catarinensis And Arachis Pintoi To Shade Conditions, A. N. A. Pachas, E. J. Jacobo, M. C. Goldfarb, S. M. Lacorte

IGC Proceedings (1993-2023)

In the north-east of Argentina, there are more than 100,000 hectares of silvopastoral systems where trees, forages and livestock are combined with the goal to diversify income, reduce financial risk, obtain more profit and enhance environmental benefit (Cubbage et al. 2013). The rapid adoption of this production system by farmers has generated high demand for information on shade tolerant grass and legume forage species.

Axonopus catarinensis is a native grass from Itajai Vally (Brazil) that was introduced to the north-east of Argentina 10 years ago; whereas Arachis pintoi is a sub-tropical legume (also native to Brazil) adapted to acid …

The Growth Response Of Tropical And Sub-Tropical Forage Species To Increasing Salinity, Hayley E. Giles, Christopher J. Lambrides, Scott A. Dalzell, David C. Macfarlane, H. Max Shelton

IGC Proceedings (1993-2023)

There is currently a growing coal seam gas (CSG) industry in Queensland, Australia. The industry requires beneficial-use strategies to consume the significant volumes of water released during CSG extraction. Irrigation of tropical and sub-tropical forage species for beef production is one option, however coal seam (CS) water is of varying quality due to moderate to high salinity and alkalinity. The application of chemically amended CS water over time could potentially increase soil salinity, which is known to reduce plant biomass production. While there were studies of salinity tolerance of many tropical and sub-tropical forage species 30 years ago, there is …

Measuring Summer Dormancy Of Perennial Grasses In Contrasting Environments, Mark R. Norton, Richard A. Culvenor, Florence Volaire

IGC Proceedings (1993-2023)

The summer dormancy trait has been shown to confer enhanced levels of survival to temperate perennial forage species over long periods of intense summer drought (Volaire and Norton 2006) and is therefore valuable in plant improvement. Normally found in species endemic to drier Mediterranean climates it is recommended that the trait be measured in the field under typical Mediterranean hot, dry summer conditions (Norton et al. 2008). However, this trait has potential utility in regions with summers that can receive substantial rainfall, but still experience extended periods of intense moisture deficit. Therefore, it is important to determine whether summer …

Generation Of Transgenic Tall Fescue Plants With Enhanced Abiotic Stress Tolerance, I. Alam, Y. G. Kim, K. H. Kim, N. Y. Ahn, B. H. Lee

IGC Proceedings (1993-2023)

Environmental stresses, such as drought, salinity and temperature extremes significantly decrease the yield of forage crops. Therefore, traits associated with abiotic stress-tolerance are of prime importance for their improvement. Biotechnological approaches have the potential to accelerate and complement conventional breeding by extending the range of gene sources for valuable traits, thus offering new opportunities for forage improvement. Transgenic technology appears as an efficient biotechnological tool of molecular breeding for improving forage quality and yield as well as tolerance to various environmental stresses. Occurrence of high level of reactive oxygen species (ROS) is a common phenomenon in abiotic stress-challenged plants. Plants …

Physiological Response Of 14 Lotus Tenuis Genotypes Subjected To Drought Conditions, Luis Inostroza, Hernán Acuña

IGC Proceedings (1993-2023)

Lotus tenuis L. is a perennial forage species of European origin. It is found in Chile in a wide range of environments between the Valparaíso (32°S) and Bíobío Regions (38°S), with a strong presence in areas with clay and volcanic soils of medium texture with problems of moisture retention. The Instituto de Investigaciones Agropecuarias (INIA) perennial forage legume breeding program has focused on developing drought-tolerant cultivars of the species. A population of 100 individuals was selected in previous studies, and all individuals were agronomically and physiologically characterized under field and greenhouse conditions. Results led to the selection of a sub-population …

Scenario Analysis: Risk And Return Of Aluminium Tolerant Lucerne, Claire D. Lewis, J. L. Jacobs, K. F. Smith, G. Spangenberg, B. Malcolm

IGC Proceedings (1993-2023)

Lucerne (Medicago sativa) yield is limited by aluminium stress associated with acid soils (Campbell et al. 1988; Scott et al. 2008). With the aid of transgenic technologies, the development of aluminium tolerant (Al Tol) lucerne is proposed. Modelled scenario analysis was conducted to explore the potential net benefits of Al Tol lucerne as part of a grazing system for a sheep production system in the high rainfall zone of south west Victoria.

Germplasm Evaluation And Frost Tolerance Improvement Of Setaria Sphacelata In Uruguay, Rafael Reyno, Javier Do Canto, Daniel Real

IGC Proceedings (1993-2023)

Setaria sphacelata (Schumach.) Stapf & C.E. Hubb is a highly productive warm-season grass that has been eva-luated in Uruguay since the 1970s (Mas 2007). It is one of the most productive and promising subtropical grasses for the Uruguayan climatic conditions. Some of the most re-markable attributes of interest are its palatability, ease to establish from seed, highly persistent, adapted to a wide range of soils, and some frost tolerance. Cultivars ‘Narok’ and ‘Kazungula’ were the only materials evaluated and no genetic improvement was conducted in Uruguay. These cultivars present some limitations, such as low seed yields and quality, and susceptibility …

Effects Of Organic Acids On Alleviation Of Aluminum Toxicity In Alfalfa, Yuan An, Peng Zhou

IGC Proceedings (1993-2023)

On a global scale, acidic soils cover an estimated 37.8 million km² of the earth's surface, and up to 50% of the world’s potentially arable soils are acidic. Aluminum (Al) is highly abundant in acid soil conditions. At low (< 5.5) pH, a toxic form of aluminum, Al³⁺, is solubilized from aluminosilicate clay minerals into soil solutions. High concentrations of Al_³⁺ in soil solutions caused seriously damage to plants by enhancing lipid per-oxidation, limiting root elongation and nutrient uptake, as well as decreasing plant growth (Kochian et al. 2005). Al toxicity represents one of the most important constraints for agricultural production in areas …

Performance Of Some Forages Species (Festuca Arundinacea L., Chloris Gayana Var. Katambora, Lotus Corniculatus L. And Medicago Sativa L.) In Saline Soil, Süleyman Temel, Uğur Şimşek, Bilal Keskin, İbrahim H. Yılmaz

IGC Proceedings (1993-2023)

Salinity is a soil degradation process which reduces plant diversity and agricultural productivity, decreases fertility and devalues the land in regions with arid and semi-arid climate. This process inhibits water and nutrient intake of plants from soil due to changeable nitrogen percentage and/or the intensity of soluble salt concentration. When the fact that agricultural lands are limited around the world and that the need for nutrition increases incrementally is taken into consideration, it is obvious that available lands should be used more effectively. Hence, it is quite crucial to reclaim saline soil and utilize it more economically (Woods 1996).

Salt Secretion Is Essential For Xero-Halophyte Reaumuria Soongorica Responding To Osmotic Stress, Ai-Ke Bao, Hang-Yu Zhou, Suomin Wang

IGC Proceedings (1993-2023)

Reaumuria soongorica, a xero-halophyte semi-shrub belonging to Tamaricaceae with excellent adaptability to adverse arid and salinity environments of northwest China, serves important ecological roles in the improvement of saline-alkali soil and dune stabilisation, and also is an attractive fodder shrub in desert steppe (Ma et al. 2011). Previous studies demonstrated that secreting salt via salt glands is an important strategy for R. soongorica adapting to high salinity environments (Zhou et al. 2012). However, very little is known about the role of salt secretion in the plant’s responses to drought. Therefore, in the present work, R. soongorica seedlings …

Assessment Of Summer Drought Tolerance And Persistence Of Some Grass Cultivars In Algerian Semi Arid Conditions, Mohamed Mefti, Hamena Bouzerzour, Abderrezak Chebouti, Aissa Abdelguerfi

IGC Proceedings (1993-2023)

Stress-tolerant forage resources are increasingly needed for the environmental and economic sustainability of extensive Mediterranean livestock systems. Perennial forages belonging to two species: Festuca arundinacea Schreb. (tall fescue) and Dactylis glomerata L. (cocksfoot) can be a valuable alternative to annuals, if they can survive across successive summer droughts. Poor persistence of sown perennial pasture grasses is a problem in regions of the World with Mediterranean climates where the most stressful, life threatening season is a summer characterised by long and often severe droughts with high temperatures. The objective of this study is to compare 14 grass cultivars in an Algerian …

Summer Dormancy And Survival Of Tall Fescue In Relation To Endophyte Presence, J. L. Thomas, Charles P. West, D. P. Malinowski

IGC Proceedings (1993-2023)

True summer dormancy in temperate perennial grasses is the ability to survive summer stresses by ceasing growth and senescing vegetative tissues independently of water supply, as opposed to summer-active grasses, which respond to rains by continuing growth, but senesce during droughts (Volaire and Norton 2006). Summer dormancy is a common drought-escape mechanism for Mediterranean-origin perennial grasses, but is also being considered as a potentially useful trait in semiarid to humid zones whose climates are not strictly Mediterranean, but where temperate grass survival is threatened by summer heat and water deficits (Malinowski et al. 2005). Moreover, summer dormancy may provide …

Screening Of Ssr Primers And Evaluation Of Salt Tolerance In 20 Sweet Sorghum Varieties For Silage, Qiuwen Zhan, Chunfei Shu, Xiaoliang Li, Min Zhan, Jieqin Li, Ping Lin

IGC Proceedings (1993-2023)

Sweet sorghum belongs to the genus Sorghum in the family Gramineae. It is a variant of common grain sorghum, with characteristics of resistance to drought, flood, barren soil and soil salinity and alkalinity (Zhan et al. 2008). Since the stem of sweet sorghum is rich in sugar, it is usually harvested as silage fodder in grasslands. Often arable land used for forage production is salt-affected. Chinnusamy et al. (2005) have screened and identified a large range of different varieties for salinity tolerance, but there are no published reports of studies screening SSR primers and evaluating the salt tolerance in …

Plantain (Plantago Lanceolata) Outperforms Chicory (Cichorium Intybus) Under Moisture Stress In Glasshouse, Lydia M. Cave, Peter D. Kemp, Paul R. Kenyon, Stephen T. Morris

IGC Proceedings (1993-2023)

Forage chicory (Cichorium intybus) and plantain (Plantago lanceolata) are now widely used throughout the world as high feed quality perennial herbage (Sanderson et al. 2003; Labreveux et al. 2006; Li et al. 2010; Golding et al. 2011; Hutton et al. 2011). Both are taprooted plants and are thus likely to confer a degree of drought tolerance through accessing water deeper in the soil profile (Kemp et al. 2010). Nie et al. (2008) reported chicory can tolerate moisture stress to a greater degree than plantain. However, overall little is known …