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Heat and drought are major stresses that significantly reduce seed yield of the common bean (Phaseolus vulgaris L.). In turn, this affects the profitability of the crop in climatic-vulnerable tropical arid regions, which happen to be the poorest and in most need of legume proteins. Therefore, it is imperative to broaden the sources of heat and drought resistance in the common bean by examining closely related species from warmer and drier environments (i.e., Tepary bean, P. acutifolius A. Gray), while harnessing such variation, typically polygenic, throughout advanced interspecific crossing schemes. As part of this study, interspecific congruity backcrosses for high temperature and drought tolerance conditions were characterized across four localities in coastal Colombia. Genotypes with high values of CO2 assimilation (>24 µmol CO2 m−2 s−1), promising yield scores (>19 g/plant), and high seed mineral content (Fe > 100 mg/kg) were identified at the warmest locality, Motilonia. At the driest locality, Caribia, one intercrossed genotype (i.e., 85) and the P. acutifolius G40001 control exhibited sufficient yield for commercial production (17.76 g/plant and 12.76 g/plant, respectively). Meanwhile, at southernmost Turipaná and Carmen de Bolívar localities, two clusters of genotypes exhibited high mean yield scores with 33.31 g/plant and 17.89 g/plant, respectively, and one genotype had an increased Fe content (109.7 mg/kg). Overall, a multi-environment AMMI analysis revealed that genotypes 13, 27, 82, and 84 were environmentally stable with higher yield scores compared to the Tepary control G40001. Ultimately, this study allows us to conclude that advanced common bean × Tepary bean interspecific congruity backcrosses are capable of pyramiding sufficient polygenic tolerance responses for the extreme weather conditions of coastal Colombia, which are likely to worsen due to climate change. Furthermore, some particular recombination events (i.e., genotype 68) show that there may be potential to couple breeding for heat and drought tolerance with Fe mineral biofortification, despite a prevalent trade-off, as a way to fight malnutrition of marginalized communities in tropical regions.

Assessing interspecific adaptive genetic variation across environmental gradients offers insight into the scale of habitat-dependent heritable heterotic effects, which may ultimately enable pre-breeding for abiotic stress tolerance and novel climates. However, environmentally dependent allelic effects are often bypassed by intra-specific single-locality genome-wide associations studies (GWAS). Therefore, in order to bridge this gap, this study aimed at coupling an advanced panel of drought/heat susceptible common bean (Phaseolus vulgaris L.) × tolerant tepary bean (P. acutifolius A. Gray) interspecific lines with last-generation multi-environment GWAS algorithms to identify novel sources of heat and drought tolerance to the humid and dry subregions of the Caribbean coast of Colombia, where the common bean typically exhibits maladaptation to extreme weather. A total of 87 advanced lines with interspecific ancestries were genotyped by sequencing (GBS), leading to the discovery of 15,645 single-nucleotide polymorphism (SNP) markers. Five yield traits were recorded for each genotype and inputted in modern GWAS algorithms (i.e., FarmCPU and BLINK) to identify the putative associated loci across four localities in coastal Colombia. Best-fit models revealed 47 significant quantitative trait nucleotides (QTNs) distributed in all 11 common bean chromosomes. A total of 90 flanking candidate genes were identified using 1-kb genomic windows centered in each associated SNP marker. Pathway-enriched analyses were done using the mapped output of the GWAS for each yield trait. Some genes were directly linked to the drought tolerance response; morphological, physiological, and metabolic regulation; signal transduction; and fatty acid and phospholipid metabolism. We conclude that habitat-dependent interspecific polygenic effects are likely sufficient to boost common bean adaptation to the severe climate in coastal Colombia via introgression breeding. Environmental-dependent polygenic adaptation may be due to contrasting levels of selection and the deleterious load across localities. This work offers putative associated loci for marker-assisted and genomic selection targeting the common bean’s neo-tropical lowland adaptation to drought and heat.

Assessing interspecific adaptive genetic variation across environmental gradients offers insight into the scale of habitat-dependent heritable heterotic effects, which may ultimately enable pre-breeding for abiotic stress tolerance and novel climates. However, environmentally dependent allelic effects are often bypassed by intra-specific single-locality genome-wide associations studies (GWAS). Therefore, in order to bridge this gap, this study aimed at coupling an advanced panel of drought/heat susceptible common bean (Phaseolus vulgaris L.) × tolerant tepary bean (P. acutifolius A. Gray) interspecific lines with last-generation multi-environment GWAS algorithms to identify novel sources of heat and drought tolerance to the humid and dry subregions of the Caribbean coast of Colombia, where the common bean typically exhibits maladaptation to extreme weather. A total of 87 advanced lines with interspecific ancestries were genotyped by sequencing (GBS), leading to the discovery of 15,645 single-nucleotide polymorphism (SNP) markers. Five yield traits were recorded for each genotype and inputted in modern GWAS algorithms (i.e., FarmCPU and BLINK) to identify the putative associated loci across four localities in coastal Colombia. Best-fit models revealed 47 significant quantitative trait nucleotides (QTNs) distributed in all 11 common bean chromosomes. A total of 90 flanking candidate genes were identified using 1-kb genomic windows centered in each associated SNP marker. Pathway-enriched analyses were done using the mapped output of the GWAS for each yield trait. Some genes were directly linked to the drought tolerance response; morphological, physiological, and metabolic regulation; signal transduction; and fatty acid and phospholipid metabolism. We conclude that habitat-dependent interspecific polygenic effects are likely sufficient to boost common bean adaptation to the severe climate in coastal Colombia via introgression breeding. Environmental-dependent polygenic adaptation may be due to contrasting levels of selection and the deleterious load across localities. This work offers putative associated loci for marker-assisted and genomic selection targeting the common bean's neo-tropical lowland adaptation to drought and heat.

Eggplant represents one of the most widely accepted vegetables in the Colombian Caribbean region due to its cultural and socio-economic importance. In this region, 585 ha were cultivated with a production of 4,298 t, in 2018, grouping 900 growers and representing 93% of the national production. However, despite its representativeness, no characterization studies of the species are evidenced. Therefore, the aim of this study was to reveal the socioeconomic, productive, and technologicalaspects linked to eggplant cultivation in productive areas from the Colombian Caribbean region. In that order, structured surveys were designed and applied. The information was analyzed through multivariate statistical methods, such as Gower’s distance and Ward’s hierarchical agglomerative clustering method. In general, the results revealed a low-medium technological level associated with eggplant production in thisregion of Colombia. Of the five groups identified, the highest level of schooling was found in groups GIV and GV, which also obtained the highest yields with 35 t ha-1 and 32 t ha-1, respectively. Sowings predominate in the month of April; this activity is related to the occurrence of precipitation in this period and the general lack of irrigation technologies by growers.

Contextualización: El área de siembra del cultivo de estevia ha venido creciendo de manera significativa, debido a las nuevas tendencias de consumo de alimentos naturales, bajos en calorías. Los efectos de las altas radiaciones, debidas al cambio climático global, han evidenciado la necesidad de desarrollar nuevos estudios sobre el comportamiento fisiológico de los pigmentos fotosintéticos de las especies agrícolas.    Vacío de conocimiento: El desconocimiento del comportamiento de los cultivos de estevia frente a los cambios actuales y futuros del ambiente (principalmente ante aumentos  de los niveles de radiación solar) hace que los agricultores y productores no obtengan los rendimientos esperados.    Propósito del estudio: El objetivo de este estudio fue analizar el efecto de diferentes niveles de radiación solar y de fertilización nitrogenada,  en condiciones controladas,  en la producción de pigmentos fotosintéticos  de Stevia rebaudiana Bert.    Metodología: El ensayo se estableció mediante un diseño estadístico completamente al azar (DCA), bajo un arreglo factorial 2 x 6, y 16 repeticiones por tratamiento; el factor A correspondió a dos niveles de radiación solar incidente (300 y 1500 μmol de fotones. m-2 s-1 correspondientes al 20 % y 100 % de radiación respectivamente) y el factor B a seis dosis de nitrógeno (0, 60, 120, 180, 240 y 300 kg ha-1). Se evaluó el contenido de clorofilas a, b y total en hojas jóvenes y sanas a los ocho meses después del trasplante.    Resultados y conclusiones: Los resultados evidenciaron que los contenidos de clorofilas a, b y total fueron afectados significativamente por la radiación solar, pero no por los niveles de nitrógeno. En ambos ambientes de radiación, los contenidos de clorofila a fueron superiores a los de clorofila b. En el ambiente de menor radiación solar se presentaron los máximos contenidos de los pigmentos fotosintéticos. En el ambiente de 1500 µmol de fotones m-2 s-1, los contenidos de clorofilas a, b y total fueron menores en las plantas que no se fertilizaron.  

Genome Wide Associations Studies GWAS are a powerful strategy for the exploration adaptive genetic variation to drought stress in advanced lines in common bean with interspecific genotypes, yet they still lack behind in the use of arid multi-environments as the subregions of the Colombian Caribbean. In order to bridge this gap, we couple an advanced genotypes panel integrated with Common Bean (Phaseolus vulgaris L.) × Tepary Bean (P. acutifolius A. Gray) interspecific lines with GWAS algorithms to identify novel sources of drought tolerance across the subregions of Colombian Caribbean. One of the most important challenges in agriculture is to achieve food security in environments vulnerable to climate change which worsens with the passing of the years. The common bean, a key product of the food basket of vulnerable regions of the Caribbean is affected by the reduction in yield under drought stress. A total of 87 advanced accessions with interspecific lines were genotyped by sequencing (GBS), leading to the discovery of 15,645 single-nucleotide polymorphism (SNP) markers. Five yield traits were developed for each accession and inputted in GWAS algorithms (i.e. FarmCPU, and BLINK) to identify putative associated loci in drought stress. Best-fit models revealed 47 significantly associated alleles distributed in all 11 common bean chromosomes. Flanking candidate genes were identified using 1-kb genomic windows centered in each associated SNP marker. A pathways enriched analysis was carried out using the mapped output in the GWAS step for each yield traits indices. Some of these genes were directly linked to response mechanisms of drought stress to level morphological, physiological, metabolic, signal transduction, and fatty acid and phospholipid metabolism. This work offers putative associated loci for marker-assisted and genomic selection for drought tolerance in common bean. It also demonstrates that it is feasible to identify genome-wide associations with an interspecific panel of genotypes and modern GWAS algorithms in multiples environments.

El objetivo de este trabajo fue caracterizar a nivel tecnológico y económico el sistema de producción de ají dulce en la región Caribe de Colombia. Se aplicó una encuesta a 60 agricultores a través de la técnica de muestreo aleatorio simple. Los retornos económicos se analizaron en las zonas productoras de San Juan del Cesar, en el departamento de la Guajira, y Ponedera, en el departamento del Atlántico, siendo en promedio 0.6 hectáreas las zonas empleadas para la siembra de ají dulce. La edad promedio de los agricultores es de 51 años, con más de 11 años de experiencia en este cultivo. Los resultados muestran diferencias en cuanto a la eficiencia de la producción; por ejemplo se encontró que es mayor para la localidad de San Juan del Cesar debido a que los rendimientos son mayores en 7 t/[ha.sup.-1]. En esta región, los ingresos netos son mayores por una diferencia de COP 6.399.270 [ha.sup.-1], con relación a la localidad de Ponedera. Se concluye que la cadena productiva no se halla bien integrada, por cuanto los márgenes de comercialización, en general, son de 0.69, lo cual revela que el agricultor es quien menos participa de este excedente generado por el mercado.

The objective of this work was to characterize technologically and economically the sweet chili pepper production system in the Caribbean region of Colombia. A survey was applied to 60 farmers using the simple random sampling technique. The economic returns were analyzed in the producing areas of San Juan del Cesar, in the department of La Guajira, and Ponedera, in the department of Atlántico, with an average of 0.6 hectares of the areas used for planting the sweet chili pepper. The average age of the farmers is 51 years old, with more than 11 years of experience in this crop. The results present differences in terms of production efficiency; for example, it was found that it is higher for the town of San Juan del Cesar, which is explained because the yields are higher by 7 t/ha- 1. In this zone, the net income is higher by a difference of COP 6.399.270 ha-1, concerning the town of Ponedera. It is concluded that the productive chain is not well integrated since the margins of commercialization, in general, are 0.69, which reveals that the farmer is the one who least participates in this surplus generated by the market.