Plant Pathology Commons^™

Morphological Divergence Among Progeny Of Macroptilium Lathyroides Accessions From The Semi-Arid Region Of Pernambuco, Brazil, Mércia V. F. Dos Santos, Gabriella P. De Albuquerque, Márcio V. Da Cunha, Mário De A. Lira Jr., José C. B. Dubeux Jr., Marta G. S. Da Silva, Mário De A. Lira, Alexandre C. L. De Mello

IGC Proceedings (1977-2023)

Macroptilium is a legume genus with approximately 20 species, usually annual or biennial, herbaceous and distributed mainly in the Americas. It is widely used as a forage resource in grasslands and usually fixes atmospheric N. Martins et al. (2001) indicated that half-sib family selection with progeny testing is the most common plant breeding method used in Brazil. In the scientific literature, however, there are few studies dedicated to Macroptilium spp.

This study evaluated morphological divergence among Macroptilium spp. progeny from accessions collected in 4 counties located in the semi-arid region of Pernambuco State, NE Brazil.

Selecting New Brachiaria Humidicola Hybrids For Western Brazilian Amazon, Giselle M. L. De Assis, Cacilda B. Valle, Carlos M. S. De Andrade, Judson F. Valentim

IGC Proceedings (1977-2023)

Brachiaria humidicola is a perennial and stoloniferous forage grass, with excellent adaptation to infertile soils and waterlogging. Producers in northern Brazil have become interested in this species, especially after the degradation of large areas of lowly permeable soils sown with B. brizantha cv. Marandu, which is highly intolerant of soil waterlogging (Andrade and Valentim 2006). However, since only 3 cultivars of B. humidicola are registered in Brazil (Mapa 2013), there is a need to develop new cultivars adapted to the range of environmental conditions experienced. Recently, Embrapa Beef Cattle obtained intraspecific hybrids of B. humidicola that need to be evaluated …

Brs Mandobi: A New Forage Peanut Cultivar Propagated By Seeds For The Tropics, Giselle M. L. De Assis, Judson F. Valentim, Carlos M. S. De Andrade

IGC Proceedings (1977-2023)

Forage peanut (Arachis pintoi) is a forage legume of relatively recent use in beef and dairy cattle feeding. Although it is native exclusively to Brazil, the first cultivar, Amarillo, was released in Australia in 1987. Forage peanut has a great number of favourable attributes for establishing grass-legume mixtures, which guarantee the persistence and high yields of high quality forage in cultivated pastures. Therefore, studies with this species have intensified in many tropical regions of the world (Assis and Valentim 2009). In the state of Acre, western Brazilian Amazon, 137,000 ha are cultivated with forage peanut, cv. Belmonte, benefiting …

Pengaruh Invigorasi Benih Hanjeli (Coix Lacryma-Jobi L.) Terdeteriorasi Terhadap Mutu Fisiologis Serta Dampaknya Terhadap Hasil, Sumadi, Tati Nurmala

Jurnal Kultivasi

Invigorasi benih merupakan upaya perbaikan mutu benih terdeteriorasi dengan berbagai zat pengatur tumbuh, pestisida yang diperkaya dengan hormon tumbuh, dan agen hayati. Tujuan penelitian adalah untuk menentukan substansi yang tepat bagi invigorasi benih hanjeli terdeteriorasi serta dampaknya terhadap hasil biji Benih bermutu tinggi merupakan salah faktor yang mempengaruhi pertumbuhan dan hasil tanaman.Percobaan pot dilaksanakan mulai bulan November 2015 sampai dengan Juni 2016 di Kebun Percobaan Fakultas Pertanian, Universitas Padjadjaran, kampus Jatinangor, Sumedang. Percobaan dirancang dengan Rancangan Petak Terbagi diulang tiga kali. Petak utama adalah dua tingkat vigor benih, yaitu benih bervigor sedang (daya berkecambah ± 80%) dan benih terdeteriorasi (bervigor …

Urinary Excretion Of Mimosine Derivatives By Cows With And Without Experience In Consumption Of Leucaena Leucocephala, N. E. Ruz-Ruiz, Eduardo G. Briceño-Poot, A. J. Ayala-Burgos, C. F. Aguilar-Pérez, Francisco J. Solorio-Sánchez, Luis Ramírez-Avilés, Juan C. Ku-Vera

IGC Proceedings (1977-2023)

Leucaena leucocephala is a leguminous tree widely distributed in the tropical regions of the world. In Mexico, it has been incorporated into silvopastoral systems and is highly regarded, owing to its high content of crude protein. Nonetheless, L. leucocephala contains secondary metab-olites, such as mimosine, a non-protein free amino acid, which may induce toxic effects in unadapted ruminants that consume the forage (Hammond 1995). Although Synergistes jonesii, an anaerobic bacterium, has the ability to degrade 3,4-DHP and 2,3-DHP to non-toxic compounds (Allison et al. 1992), in Mexico its presence has not yet been confirmed. Recent work has suggested …

Urinary Excretion Of Mimosine Metabolites By Hair Sheep Fed Foliage Of Leucaena Leucocephala, L. M. Contreras-Hernández, N. E. Ruz-Ruiz, Eduardo G. Briceño-Poot, Luis Ramírez-Avilés, A. J. Ayala-Burgos, C. F. Pérez-Aguilar, Francisco J. Solorio-Sánchez, Juan C. Ku-Vera

IGC Proceedings (1977-2023)

Leucaena leucocephala is an adapted legume widely distributed in the tropical regions of Mexico. The high crude protein content of leucaena leaves renders it appropriate for ruminant feeding under commercial conditions. However, the foliage contains the non-protein amino acid mimosine, which, if consumed in high amounts, may induce toxicity in animals which have not previously consumed the legume or without microorganisms capable of degrading mimosine and its derivatives 2,3-DHP (dihydroxypyridine) and 3,4-DHP (Hammond 1995, Palmer et al. 2010, Dalzell et al. 2012). Barros-Rodríguez et al. (2012) found that dry matter intake and weight gain were reduced when …

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 (1977-2023)

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 (1977-2023)

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 (1977-2023)

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 (1977-2023)

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 (1977-2023)

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 (1977-2023)

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 (1977-2023)

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 (1977-2023)

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 (1977-2023)

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 (1977-2023)

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 (1977-2023)

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 (1977-2023)

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 (1977-2023)

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 (1977-2023)

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 …