Hibridaciones interespecificas para el mejoramiento de Phaseolus vulgaris L.

A study was initiated to determine the barriers that limit the transferences of genes between Phaseolus vulgaris and P. coccineus. The factors that determine the outcome of this crossing are the direction (success is greater when P. vulgaris is used as the mother parent) and the combination of parents. Early generations show reduced viability and fertility. This reduction is more pronounced in progenies P. vulgaris x P. coccineus subspecie coccineus compared with progenies P. vulgaris x P. coccineus subspecie polyanthus. It also depends on the combination of parents. In later generations a progressive restoration of viability and fertility was observed. The combination of parents greatly affects the type of segregation of the characteristics in progeny observed in F2 of P. vulgaris x P. coccineus subspecie coccineus crossing. Moreover, results seem to indicate that in progenies P. vulgaris x P. coccineus subspecie polyanthus there are more possibilities of recombination. Interesting materials were selected for improvement of plant architecture (resistance to lodging, long hypocotyl and epicotyl, small folioles) and disease resistance (tolerance to BGMV). Some suggestions are made on future activities of the project of interspecific crosses: multiplication and evaluation of the P. coccineus collection, studies on segregation, projects on crosses fox specific objectives. (AS-CIAT

Etapas de desarrollo en la planta de frijol

The developmental scale of the bean crop and the general characteristics of plant development are described on the basis of morphological and physiological changes in the plant. The factors influencing the duration of the developmental stages of beans are identified, namely growth habit, earliness, and climate. (CIAT)Se describen las etapas de la escala del desarrollo del cultivo de frijol y las caracteristicas generales del desarrollo de la planta con base en los cambios morfologicos y fisiologicos de la misma. Se identifican los factores que influyen en la duracion de las etapas de desarrollo del frijol: habito de crecimiento, precocidad y clima. (CIAT

Microsatellite diversity and genetic structure among common bean (Phaseolus vulgaris L.) landraces in Brazil, a secondary center of diversity

Brazil is the largest producer and consumer of common bean (Phaseolus vulgaris L.), which is the most important source of human dietary protein in that country. This study assessed the genetic diversity and the structure of a sample of 279 geo-referenced common bean landraces from Brazil, using molecular markers. Sixty-seven microsatellite markers spread over the 11 linkage groups of the common bean genome, as well as Phaseolin, PvTFL1y, APA and four SCAR markers were used. As expected, the sample showed lower genetic diversity compared to the diversity in the primary center of diversification. Andean and Mesoamerican gene pools were both present but the latter gene pool was four times more frequent than the former. The two gene pools could be clearly distinguished; limited admixture was observed between these groups. The Mesoamerican group consisted of two sub-populations, with a high level of admixture between them leading to a large proportion of stabilized hybrids not observed in the centers of domestication. Thus, Brazil can be considered a secondary center of diversification of common bean. A high degree of genome-wide multilocus associations even among unlinked loci was observed, confirming the high level of structure in the sample and suggesting that association mapping should be conducted in separate Andean and Mesoamerican Brazilian samples

Different Seed Selection and Conservation Practices for Fresh Market and Dried Chile Farmers in Aguascalientes, Mexico

Different Seed Selection and Conservation Practices for Fresh Market and Dried Chile Farmers in Aguascalientes, Mexico. The process of selecting and saving seed is the most basic and oldest of agricultural practices. In today’s modern and highly capital-intensive agriculture, seeds are often treated like another chemical input. This study sought to examine seed selection and saving practices among chile farmers in Aguascalientes, Mexico, where both industrial and traditional agriculture are practiced. We observed a clear division among farmers who plant chile peppers commercially. Sixty-eight chile pepper farmers were surveyed in order to document seed selection and saving practices. Fifteen respondents (22%) planted chile peppers destined for the fresh market and all utilized purchased commercial seed of F1 hybrid varieties. Fifty-three farmers (78%) planted chiles to be dried and either saved their own or purchased seeds that others had saved and selected. Farmers who saved their own seed sought to maintain an ideotype, rather than directionally select for certain traits, much like Cleveland et al. (2000) chronicled in central Mexican maize farmers. Farmers would benefit from a participatory plant-breeding program in order to maintain productive seed stock for the continued cultivation of dried chile pepper in the state

Selection and adaptive introgression guided the complex evolutionary history of the European common bean

: Domesticated crops have been disseminated by humans over vast geographic areas. Common bean (Phaseolus vulgaris L.) was introduced in Europe after 1492. Here, by combining whole-genome profiling, metabolic fingerprinting and phenotypic characterisation, we show that the first common bean cultigens successfully introduced into Europe were of Andean origin, after Francisco Pizarro's expedition to northern Peru in 1529. We reveal that hybridisation, selection and recombination have shaped the genomic diversity of the European common bean in parallel with political constraints. There is clear evidence of adaptive introgression into the Mesoamerican-derived European genotypes, with 44 Andean introgressed genomic segments shared by more than 90% of European accessions and distributed across all chromosomes except PvChr11. Genomic scans for signatures of selection highlight the role of genes relevant to flowering and environmental adaptation, suggesting that introgression has been crucial for the dissemination of this tropical crop to the temperate regions of Europe

Application of genomicsassisted breeding for generation of climate resilient crops: progress and prospects

CCAFS Climat