Cambios climáticos y beneficios económicos en la utilización de variedades de frijol tolerantes a temperaturas altas para agricultores en Atlántida, Honduras.

Rising ambient air temperatures, migration, and deforestation threaten the sustainability of hillside agriculture in Atlántida, Honduras. Currently, farmers avoid climatic constraints to common bean production by planting at different altitudes during different seasons. However, this practice may become less effective because of climatic change. The analysis of historical weather data from 14 weather stations indicates that Honduras is undergoing climatic warming and GIS analysis shows a significant proportion of bean production under high temperature stress conditions. Farmers in ten villages in Atlántida, five at a lower altitude and five at a higher altitude, were interviewed in regard to their knowledge and experience with climatic change and bean production. Differences in bean production and yield between the low altitude and high altitude villages were attributed mainly to climatic constraints, due to differences in elevation. Under base scenario assumptions, a cost/benefit analysis indicates that the development and introduction of heat-tolerant bean varieties could produce significant returns and help to alleviate heat-related constraints on bean production.El aumento en temperatura ambiental, la emigración y la deforestación amenazan la agricultura sustentable en la zona montañosa de Atlántida, Honduras. Para evitar limitaciones climáticas, agricultores de esta zona producen frijol mediante siembras a distintas elevaciones. Sin embargo, esta práctica puede ser poco efectiva debido a cambios climáticos. Estudios de datos climatológicos históricos obtenidos de 14 estaciones meteorológicas indican que la temperatura ambiental en Honduras va en aumento. Estudios de información geográfica demuestran que gran parte de la producción de frijol ocurre en áreas donde las temperaturas son elevadas. Se entrevistaron agricultores en villas localizadas en elevaciones altas y en elevaciones bajas para determinar sus experiencias con cambios climáticos y el efecto en la producción de frijol. Las diferencias en rendimiento fueron causadas por limitaciones climáticas atribuidas a la producción de frijol a diferentes elevaciones. Un análisis de costos/beneficios indica que el desarrollo y la introducción de variedades tolerantes a temperaturas altas pueden resultar en ganancias sustanciales para el agricultor mediante la disminución de problemas asociados a altas temperaturas en la producción de frijol

Desarrollo de modelos lineales para la determinación del área foliar en habichuela (Phaseolus vulgaris L.) a partir de medidas directas de hojas

Plant leaf area is an important physiological trait, and direct, non-destructive methods for estimating leaf area have been shown to be effective while allowing for repeated plant sampling.The objective of this study was to evaluate direct, non-destructive leaflet measurements as predictors of actual leaflet area (LA), to test previously developed models, and to develop genotype-specific linear models for leaflet area estimation in common bean (Phaseolus vulgaris L.). For development of appropriate regression models for leaflet area estimation, four common bean genotypes were evaluated under greenhouse conditions: BAT 477, 'Morales', SER 16, and SER 21. The greenhouse-derived models were evaluated under field conditions. Previously developed models were tested and found to overestimate or underestimate leaflet area. Leaflet measurements included maximum leaflet width (W) and maximum leaflet length (L) and L X W. The measurements with the highest values for the coefficient of determination (R2) were W or L X W for BAT 477, SER 16, and Morales (0.97, 0.95, and 0.95, respectively), and L X W for SER 21 (R2 = 0.96). The linear models developed were shown to be effective and robust for predicting leaflet area under both greenhouse and field conditions during both vegetative and reproductive stages of plant development.El área foliar es una medida importante de la fisiología de las plantas, y los métodos indirectos y no-destructivos para medir el área foliar han demostrado ser muy eficientes a la vez que permiten la toma de medidas repetidas en el tiempo. El objetivo del presente estudio fue evaluar directamente métodos no destructivos para la estimación del área foliar en habichuelas (Phaseolus vulgaris L.) a partir de la medida de las hojas, probar modelos previos, y desarrollar modelos lineales específicos para cada genotipo. Se evaluaron cuatro genotipos: BAT 477, Morales, SER 16, y SER 21, bajo condiciones de invernadero y de campo. Los modelos desarrollados en invernadero se aplicaron y evaluaron bajo condiciones de campo durante dos años. Los modelos previos reportados por otros autores fueron evaluados, y se encontró que sobre-o sub-estimaban el área foliar. Los modelos desarrollados en este estudio incluyeron el ancho máximo de la hoja (W), y la longitud máxima (L), los que fueron empleados para calcular un tercer factor, L X W. Los modelos con mayores coeficientes de determinación (R2) fueron W or L X W para BAT 477, SER 16 y Morales (0.97, 0.95, y 0.95, respectivamente) y L X W para SER 21 (R2 = 0.96). Los modelos de regresión desarrollados mostraron ser eficientes en la predicción del área foliar bajo condiciones de campo e invernadero, en las fases vegetativas y reproductivas, para cada uno de los genotipos evaluados

Contributions in Puerto Rico to Bean, \u3ci\u3ePhaseolus\u3c/i\u3e spp., Research

Most literature reviews focus on a specific topic. The purpose of this paper, however, is to review the contributions made by a multidisciplinary team of researchers at a specific location (Puerto Rico) over a period of several decades. This paper documents bean research of the University of Puerto Rico and the USDA-ARS Tropical Agriculture Research Station during the past century. The following illustrates the merits of continuity of effort in research and shows that research often follows a logical sequence of actions to solve problems related to genetic improvement as well as to study biotic and abiotic factors that affect common bean production in Central America and the Caribbean. Finally, this narrative demonstrates that the ongoing development of improved bean germplasm lines and cultivars is cyclical and builds upon previous research achievements. The common bean (Phaseolus vulgaris L.) is an important component of the traditional diet in Puerto Rico. The 1900 report of the USDA Puerto Rico Agricultural Experiment Station (USDA-PRAES) noted that rice and beans were staple crops in Puerto Rico and found on the tables of both the rich and poor. Smit et al. (2007) noted that annual per capita consumption of grain legumes, mostly dry beans, in Puerto Rico (6.4 kg) is almost double the per capita consumption in the U.S. (3.4 kg; US Dry Bean Council, 2019). Common and lima beans (Phaseolus lunatus L.) have been produced in the Caribbean for at least 500 years. The grain legume fits well into rotations and is often intercropped with other longer season crops such as plantains and bananas. Small white beans, locally known as ‘Blanca del País’ and striped pink beans known as ‘Colorado del País’ are traditional market classes in Puerto Rico (Koenig, 1953). Consumers in Puerto Rico today consume a wide array of market classes including white, red, pink, pinto, black and kidney beans (Bean Institute, 2018). Although Puerto Ricans represent roughly 1% of the U.S. population, they consume 3.1% of the common and lima beans in the U.S. (Lucier et al., 2000)

GENERAL COMBINING ABILITY EFFECTS FOR REPRODUCTIVE HEAT TOLERANCE IN SNAP BEAN

GENERAL COMBINING ABILITY EFFECTS FOR REPRODUCTIVE HEAT TOLERANCE IN SNAP BEA

Improving association studies and genomic predictions for climbing beans with data from bush bean populations

Common bean (Phaseolus vulgaris L.) has two major origins of domestication, Andean and Mesoamerican, which contribute to the high diversity of growth type, pod and seed characteristics. The climbing growth habit is associated with increased days to flowering (DF), seed iron concentration (SdFe), nitrogen fixation, and yield. However, breeding efforts in climbing beans have been limited and independent from bush type beans. To advance climbing bean breeding, we carried out genome-wide association studies and genomic predictions using 1,869 common bean lines belonging to five breeding panels representing both gene pools and all growth types. The phenotypic data were collected from 17 field trials and were complemented with 16 previously published trials. Overall, 38 significant marker-trait associations were identified for growth habit, 14 for DF, 13 for 100 seed weight, three for SdFe, and one for yield. Except for DF, the results suggest a common genetic basis for traits across all panels and growth types. Seven QTL associated with growth habits were confirmed from earlier studies and four plausible candidate genes for SdFe and 100 seed weight were newly identified. Furthermore, the genomic prediction accuracy for SdFe and yield in climbing beans improved up to 8.8% when bush-type bean lines were included in the training population. In conclusion, a large population from different gene pools and growth types across multiple breeding panels increased the power of genomic analyses and provides a solid and diverse germplasm base for genetic improvement of common bean

Generation of a mutant population for TILLING common bean genotype BAT 93

Common bean (Phaseolus vulgaris) is the major food legume worldwide, making it an important target for novel approaches of genetic analysis. This study evaluated the use of ethyl methane sulfonate (EMS) for the generation of a mutant population for targeted induced local lesions in genomes (TILLING) in common bean. TILLING is a powerful reverse genetics approach that uses a large mutant population for identi?cation of mutants in loci of interest. Based on overall survival, development, and yield of treated seed, 40 mM EMS was found to be an appropriate concentration for the generation of a mutant population in common bean genotype BAT 93. Higher concentrations of EMS resulted in survival rates of less than 10% and lower concentrations resulted in the generation of fewer mutants. Based on TILLING results from other species, a population of 5000 lines is estimated to be suf?cient for saturation of the common bean genome. Phenotypic mutation frequencies and the isolation of targeted mutations in the BAT 93 mutant population indicate that mutagenesis was effective

Internal friction in hard and soft PZT-based ceramics

International audienceThis study concerns the two following commercial ceramics: PZT TRS100 (US Navy I standard: hard material) and PZT TRS600 (US Navy VI standard: soft material). These materials are PZT ceramics with various dopants. Internal friction and elastic modulus measurements have been performed versus temperature at different frequencies. Considering the hard ceramic, two relaxation peaks (R1, R2) related to oxygen vacancies–domain walls interaction were observed similarly to undoped PZT ceramics. In addition, a phase transition peak (P1) occurs at the Curie temperature. Considering the soft ceramic, only two phase transition peaks were observed. The increase of modulus associated with the phase transition internal friction peak occurs at the Curie temperature in both samples. The effects of some dopants are investigated. Some of them influence either the concentration of oxygen vacancies or the domains structure

Effect of cutting management on the forage production and quality of tepary bean (\u3ci\u3ePhaseolus acutifolius\u3c/i\u3e A. Gray)

Tepary bean (Phaseolus acutifolius A. Gray) is an underutilized drought tolerant annual legume, originating from the Sonoran Desert, that may be a beneficial forage/hay for beef cattle in the Southern Great Plains of the US (SGP). The SGP has erratic rainfall and periods of intermittent drought exacerbated by high summer temperatures. In 2020 and 2021, a split-plot design was used to evaluate 13 genotypes of tepary bean and a forage soybean (control) at El Reno, OK, USA to compare production of plant biomass and forage nutritive value parameters under seven harvest regimes. Genotypes were used as the main plot and cutting management as the sub-plot. Biomass production of all tepary bean genotypes equaled that of soybean (p \u3e 0.05), while several genotypes had superior forage nutritive value traits (p ≤ 0.05). Overall, a 15-cm cutting height and 30-day harvest interval produced the best overall product (average dry biomass of 5.8 Mg ha−1 with average relative feed values (RFV) of 165). Although all harvest regimes reduced total seasonal biomass, forage nutritive value increased. However, the tradeoff between forage production and nutritive value may be unacceptable to most producers. Further agronomic and breeding research is needed to encourage producers to grow tepary bean as a forage/hay in the SGP