Producción de anticuerpos monoclonales con aislamiento seleccionados del virus del mosaico dorado de frijol

Programa Cooperativo Regional de Frijol para Centroamérica, México y el Caribe (PROFRIJOL)Cooperación Suiza para el Desarrollo (COSUDE)Centro Internacional de Agricultura Tropical (CIAT)UCR::Vicerrectoría de Investigación::Unidades de Investigación::Ciencias Agroalimentarias::Estación Experimental Agrícola Fabio Baudrit Moreno (EEAFBM

Identification of a Strain of Peanut Chlorotic Streak Virus Causing Chlorotic Vein Banding Disease of Groundnut in India

A virus disease characterized by chlorotic vein banding, chlorotic line pattern along the margins or midrib of mature leaflets and chlorotic spots/rings was observed on commercial groundnut crops in Rayalaseema area of Andhra Pradesh with an incidence from 1% to nearly 60%. The virus was transmitted by mechanical inoculation in extracts prepared with 0.01 M potassium phosphate butter, pH 8.0 to 21 species from the Chenopodiaceae, Cruciferae, Leguminosae and Solanaceae, Chenopodium quinoa was found to be a good local lesion host. The virus was neither seed-transmitted through 1591 groundnut seeds nor aphid-transmitted by Aphis craccivora, Myzus persicae and Rhopalosiphum maidis either in non-persistent or semi-persistent manner. The virus remained infective in buffered tobacco leaf sap at a dilution of 10−5; in a 10−1 dilution of buffered sap the virus was infective for 2–3 days at 22–29°C or when heated to 65°C for 10 min but not to 70°C. Clarification treatments with organic solvents with 10% chloroform was least damaging. The virus was purified from Nicotiana rustica leaves. Purified virus contained isometric particles of 51 nm in diameter with an electron dense core of 22 nm and two major polypeptides of 76 kDa and 36 kDa. A polyclonal antiserum to this virus was produced. In agar gel double diffusion, enzyme-linked immunosorbent assay and in electro-blot immunoassay rests the virus was related to peanut chlorotic streak virus and not to cauliflower mosaic, figwort mosaic and soybean chlorotic mottle viruse

The Prehistory of Potyviruses: Their Initial Radiation Was during the Dawn of Agriculture

Background: Potyviruses are found world wide, are spread by probing aphids and cause considerable crop damage. Potyvirus is one of the two largest plant virus genera and contains about 15% of all named plant virus species. When and why did the potyviruses become so numerous? Here we answer the first question and discuss the other. Methods and Findings: We have inferred the phylogenies of the partial coat protein gene sequences of about 50 potyviruses, and studied in detail the phylogenies of some using various methods and evolutionary models. Their phylogenies have been calibrated using historical isolation and outbreak events: the plum pox virus epidemic which swept through Europe in the 20th century, incursions of potyviruses into Australia after agriculture was established by European colonists, the likely transport of cowpea aphid-borne mosaic virus in cowpea seed from Africa to the Americas with the 16th century slave trade and the similar transport of papaya ringspot virus from India to the Americas. Conclusions/Significance: Our studies indicate that the partial coat protein genes of potyviruses have an evolutionary rate of about 1.1561024 nucleotide substitutions/site/year, and the initial radiation of the potyviruses occurred only about 6,600 years ago, and hence coincided with the dawn of agriculture. We discuss the ways in which agriculture may have triggered the prehistoric emergence of potyviruses and fostered their speciation

Bean Golden Mosaic: Research Advances

El frijol (Phaseolus vulgaris L.) es una de las fuentes de proteina (15-35%) y calorías (ca. 340 caI./100 gr) más importantes en la América Latina. En esta región, centro de origen de esta especie, se producen más de cuatro millones de toneladas de frijol al año, lo cual equivale al 88% de la semilla de frijol producida en las regiones tropicales del mundo. Brasil, el mayor productor de frijol del mundo, posee un consumo per capita de cerca de 20 kg/año. En America Central, el frijol es igualmente importante, siendo consumido en la mayoría de los países centroamericanos hasta tres veces por día. Proporcionalmente, en la America Central se cultiva el doble del área que en Brasil, relativo a sus extensiones territoriales. El frijol es también producido en islas del Caribe, tales como Cuba (ca. 26.000 TM), Haití (56.000 TM) y República Dominicana (55.000 TM) según datos de 1990 (CIAT). México, el segundo productor de frijol en la America Latina, consume aproximadamente 1.2 millones de toneladas métricas de frijol al año. A pesar de que México cultiva cerca de 1.800.000 hectáreas de frijol, la demanda interna no es satisfecha en algunos años dado la baja productividad del cultivo. Esta baja productividad relativa del frijol, no solo en México sino también en el resto de la América Latina (700 kg/ha vs. 1.600 kg/ha en los Estados Unidos), es una consecuencia de los múltiples problemas bióticos y abióticos que inciden en el cultivo, en el trópico Americano. Es precisamente en las regiones productoras de frijol situadas en climas cálidos, de altitud baja a intermedia (0-1200 m.s.n.m), donde el mosaico dorado del frijol alcanza su mayor incidencia.The common bean (Phaseolus vulgaris L.) is an important source of protein and calories in Latin America. In this region, the center of origin of this legume species, over 4 million tons of dry beans are produced per year. Nevertheless, many Latin American countries, including two of the largest producers of beans in the world, Brazil and Mexico, have to import beans to meet internal demand. This shortage of beans is related to the low productivity of this crop in Latin America (700 kg /ha vs. 1,600 kg/ ha average in the USA). The low productivity in the main bean production regions of tropical America is associated to the incidence of several biotic and abiotic constraints. Among the biotic constraints, bean golden mosaic virus is undoubtedly the main bean production problem in the lowland tropics, particularly, during the dry seasons of the year.Programa Cooperativo Regional de Frijol para Centroamérica, México y el Caribe (PROFRIJOL)Cooperación Suiza para el Desarrollo (COSUDE)Centro Internacional de Agricultura Tropical (CIAT)UCR::Vicerrectoría de Investigación::Unidades de Investigación::Ciencias Agroalimentarias::Estación Experimental Agrícola Fabio Baudrit Moreno (EEAFBM