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Molecular ecology and selection in the drought-related Asr gene polymorphisms in wild and cultivated common bean (Phaseolus vulgaris L.)
Andrés J Cortés, Carolina M Chavarro, Santiago Madri?án, Dominique This, Matthew W Blair
BMC Genetics , 2012, DOI: 10.1186/1471-2156-13-58
Abstract: Our wild population samples covered a range of mesic (semi-arid) to very dry (desert) habitats, while our cultivated samples presented a wide spectrum of drought tolerance. Both genes showed very different patterns of nucleotide variation. Asr1 exhibited very low nucleotide diversity relative to the neutral reference loci that were previously surveyed in these populations. This suggests that strong purifying selection has been acting on this gene. In contrast, Asr2 exhibited higher levels of nucleotide diversity, which is indicative of adaptive selection. These patterns were more notable in wild beans than in cultivated common beans indicting that natural selection has played a role over long time periods compared to farmer selection since domestication.Together these results suggested the importance of Asr1 in the context of drought tolerance, and constitute the first steps towards an association study between genetic polymorphism of this gene family and variation in drought tolerance traits. Furthermore, one of our major successes was to find that wild common bean is a reservoir of genetic variation and selection signatures at Asr genes, which may be useful for breeding drought tolerance in cultivated common bean.
Construction and EST sequencing of full-length, drought stress cDNA libraries for common beans (Phaseolus vulgaris L.)
Matthew W Blair, Andrea C Fernandez, Manabu Ishitani, Danilo Moreta, Motoaki Seki, Sarah Ayling, Kazuo Shinozaki
BMC Plant Biology , 2011, DOI: 10.1186/1471-2229-11-171
Abstract: Two full-length cDNA libraries were constructed: one for the drought tolerant Mesoamerican genotype BAT477 and the other one for the acid-soil tolerant Andean genotype G19833 which has been selected for genome sequencing. Plants were grown in three soil types using deep rooting cylinders subjected to drought and non-drought stress and tissues were collected from both roots and above ground parts. A total of 20,000 clones were selected robotically, half from each library. Then, nearly 10,000 clones from the G19833 library were sequenced with an average read length of 850 nucleotides. A total of 4,219 unigenes were identified consisting of 2,981 contigs and 1,238 singletons. These were functionally annotated with gene ontology terms and placed into KEGG pathways. Compared to other EST sequencing efforts in common bean, about half of the sequences were novel or represented the 5' ends of known genes.The present full-length cDNA libraries add to the technological toolbox available for common bean and our sequencing of these clones substantially increases the number of unique EST sequences available for the common bean genome. All of this should be useful for both functional gene annotation, analysis of splice site variants and intron/exon boundary determination by comparison to soybean genes or with common bean whole-genome sequences. In addition the library has a large number of transcription factors and will be interesting for discovery and validation of drought or abiotic stress related genes in common bean.The legume family is the second most important crop family as a human food source after cereals and in addition provides scores of other products including fodder and feedstock, valuable timber, vegetable oil, bio-fuels, important medicines and even poisons [1]. Legumes are unequalled for stabilization and reforestation of degraded land due to their ability to fix nitrogen, compete with other plants, repel herbivory and grow on acid soils in a range of environment
Antioxidant Activity in Cotyledon of Black and Yellow Common Beans (Phaseolus Vulgaris L.)
N.E. Rocha-Guzman,J.A. Gallegos-Infante,R.F. Gonzalez-Laredo,A.M. Preza Y. Lerma,F.J. Ibarra-Perez
Research Journal of Biological Sciences , 2012,
Abstract: Methanol and aqueous acetone cotyledon extracts from two groups of different colored common beans (Phaseolus vulgaris L.), black and yellow, were analyzed for total phenolics, lipid antioxidant activity and two-dimensional thin layer chromatography. A higher yield was obtained for methanol extracts in comparison to acetone extracts. However, acetone extracts showed a higher phenol content than methanol extracts independently of the group of beans tested. Furthermore, phenolic content was higher in acetone extracts from black beans than in acetone extracts of yellow beans. A higher antioxidant activity was found in methanol extracts rather than in acetone extracts without differences in the group of beans studied. Most of antioxidant activity was associated to black beans. Thin layer chromatography showed the presence of catechins in black beans but not in yellow beans cotyledons.
Adaptation to High Temperature and Water Deficit in the Common Bean (Phaseolus vulgaris L.) during the Reproductive Period  [PDF]
Hide Omae,Ashok Kumar,Mariko Shono
Journal of Botany , 2012, DOI: 10.1155/2012/803413
Abstract: This paper reviews the adaption to heat and drought stresses in Phaseolus vulgaris, a grain and vegetable crop widely grown in both the Old and New World. Substantial genotypic differences are found in morphophysiological characteristics such as phenology, partitioning, plant-water relations, photosynthetic parameters, and shoot growth, which are related to reproductive responses. The associations between (a) days to podding and leaf water content and (b) the number of pods per plant and seed yield are consistent across different environments and experiments. Leaf water content is maintained by reductions in leaf water potential and shoot extension in response to heat and drought stress. Heat-tolerant cultivars have higher biomass allocation to pods and higher pod set in branches. These traits can be used as a marker to screen germplasm for heat and drought tolerance. In this paper, we briefly review the results of our studies carried out on heat and drought tolerance in the common bean at the Tropical Agriculture Research Front, Ishigaki, Japan. 1. Introduction Transitory or constantly high temperatures cause an array of morphoanatomical, physiological, and biochemical changes in plants, which affect plant growth and development and may lead to a drastic reduction in economic yield. The adverse effects of heat stress can be mitigated by developing crop plants with improved thermotolerance using various genetic approaches [1]. However, achieving this requires a thorough understanding of the physiological responses of plants to high temperature, the mechanisms of heat tolerance, and potential strategies for improving crop thermotolerance. The common bean (Phaseoluls vulgaris L.) is originally a crop of the New World [2], but it is now grown extensively in all major continental areas [3]. Its production spans from 52°N to 32°S latitude [4] and from near sea level in the continental US and Europe to elevations of more than 3000?m in Andean South America. The common bean has two major gene pools [5], the Andean and the Mesoamerican, based on their centers of origin in South and Central America, respectively [6]. Within these gene pools are a total of six races, including three Mesoamerican (Mesoamerica, Durango, and Jalisco) and three Andean (Peru, Nueva Granada, and Chile) [7, 8]. An additional Mesoamerican race has been designated Guatemala, which includes certain climbing beans from Central America [9]. After domestication, the common bean spread across Mesoamerica and South America and, after the European discovery of the Americas, to Europe and Africa,
Diversification and Population Structure in Common Beans (Phaseolus vulgaris L.)  [PDF]
Matthew W. Blair,Alvaro Soler,Andrés J. Cortés
PLOS ONE , 2012, DOI: 10.1371/journal.pone.0049488
Abstract: Wild accessions of crops and landraces are valuable genetic resources for plant breeding and for conserving alleles and gene combinations in planta. The primary genepool of cultivated common beans includes wild accessions of Phaseolus vulgaris. These are of the same species as the domesticates and therefore are easily crossable with cultivated accessions. Molecular marker assessment of wild beans and landraces is important for the proper utilization and conservation of these important genetic resources. The goal of this research was to evaluate a collection of wild beans with fluorescent microsatellite or simple sequence repeat markers and to determine the population structure in combination with cultivated beans of all known races. Marker diversity in terms of average number of alleles per marker was high (13) for the combination of 36 markers and 104 wild genotypes that was similar to the average of 14 alleles per marker found for the 606 cultivated genotypes. Diversity in wild beans appears to be somewhat higher than in cultivated beans on a per genotype basis. Five populations or genepools were identified in structure analysis of the wild beans corresponding to segments of the geographical range, including Mesoamerican (Mexican), Guatemalan, Colombian, Ecuadorian-northern Peruvian and Andean (Argentina, Bolivia and Southern Peru). The combined analysis of wild and cultivated accessions showed that the first and last of these genepools were related to the cultivated genepools of the same names and the penultimate was found to be distinct but not ancestral to the others. The Guatemalan genepool was very novel and perhaps related to cultivars of race Guatemala, while the Colombian population was also distinct. Results suggest geographic isolation, founder effects or natural selection could have created the different semi-discrete populations of wild beans and that multiple domestications and introgression were involved in creating the diversity of cultivated beans.
Genetic control of orange hilum corona of carioca beans (Phaseolus vulgaris)
Tomaz, Juarez Pires;Moda-Cirino, Vania;Fonseca Junior, Nelson da Silva;Ruas, Paulo Maurício;
Genetics and Molecular Biology , 2007, DOI: 10.1590/S1415-47572007000400016
Abstract: the purpose of this research was to elucidate the genetic control of orange corona color in carioca common beans (phaseolus vulgaris). we made four crosses between carioca group cultivars that differed in respect to the presence or absence of an orange hilum corona color. the f2, f3, f1bc11, f1bc21, f2bc11 and f2bc21 phenotypic segregations were evaluated with a chi-square test which fitted with the hypothesis that one gene with a dominant allele is responsible for the orange corona color. all generations resulting from the four different crosses showed segregation patterns which agreed with the expected proportions. our results show that the dominant g allele controls orange corona color in the carioca bean group.
Purification and Characterization of a Lectin from Phaseolus vulgaris cv. (Anasazi Beans)
Arishya Sharma,Tzi Bun Ng,Jack Ho Wong,Peng Lin
Journal of Biomedicine and Biotechnology , 2009, DOI: 10.1155/2009/929568
Abstract: A lectin has been isolated from seeds of the Phaseolus vulgaris cv. “Anasazi beans” using a procedure that involved affinity chromatography on Affi-gel blue gel, fast protein liquid chromatography (FPLC)-ion exchange chromatography on Mono S, and FPLC-gel filtration on Superdex 200. The lectin was comprised of two 30-kDa subunits with substantial N-terminal sequence similarity to other Phaseolus lectins. The hemagglutinating activity of the lectin was stable within the pH range of 1–14 and the temperature range of 0–80°C. The lectin potently suppressed proliferation of MCF-7 (breast cancer) cells with an IC50 of 1.3 M, and inhibited the activity of HIV-1 reverse transcriptase with an IC50 of 7.6 M. The lectin evoked a mitogenic response from murine splenocytes as evidenced by an increase in [3H-methyl]-thymidine incorporation. The lectin had no antifungal activity. It did not stimulate nitric oxide production by murine peritoneal macrophages. Chemical modification results indicated that tryptophan was crucial for the hemagglutinating activity of the lectin.
Antioxidant Activity in Cotyledon of Black and Yellow Common Beans (Phaseolus Vulgaris L.)
N.E. Rocha-Guzman,J.A. Gallegos-Infante,R.F. Gonzalez-Laredo,A.M. Preza Y. Lerma
Research Journal of Biological Sciences , 2007,
Abstract: Methanol and aqueous acetone cotyledon extracts from two groups of different colored common beans (Phaseolus vulgaris L.), black and yellow, were analyzed for total phenolics, lipid antioxidant activity and two-dimensional thin layer chromatography. A higher yield was obtained for methanol extracts in comparison to acetone extracts. However, acetone extracts showed a higher phenol content than methanol extracts independently of the group of beans tested. Furthermore, phenolic content was higher in acetone extracts from black beans than in acetone extracts of yellow beans. A higher antioxidant activity was found in methanol extracts rather than in acetone extracts without differences in the group of beans studied. Most of antioxidant activity was associated to black beans. Thin layer chromatography showed the presence of catechins in black beans but not in yellow beans cotyledons.
Pinto Beans (Phaseolus vulgaris L.) as a Functional Food: Implications on Human Health  [PDF]
Cristiane R. S. Camara,Carlos A. Urrea,Vicki Schlegel
Agriculture , 2013, DOI: 10.3390/agriculture3010090
Abstract: Most foods are considered functional in terms of providing nutrients and energy to sustain daily life, but dietary systems that are capable of preventing or remediating a stressed or diseased state are classified as functional foods. Dry beans ( Phaseolus vulgaris L.) contain high levels of chemically diverse components (phenols, resistance starch, vitamins, fructooligosaccharides) that have shown to protect against such conditions as oxidative stress, cardiovascular disease, diabetes, metabolic syndrome, and many types of cancer, thereby positioning this legume as an excellent functional food. Moreover, the United States has a rich dry bean history and is currently a top producer of dry beans in the world with pinto beans accounting for the vast majority. Despite these attributes, dry bean consumption in the US remains relatively low. Therefore, the objective of this manuscript is to review dry beans as an important US agricultural crop and as functional food for the present age with an emphasis on pinto beans.
Cell wall polysaccharides of common beans (Phaseolus vulgaris L.)
Shiga, Tania M.;Lajolo, Franco M.;Filisetti, Tullia M.C.C.;
Ciência e Tecnologia de Alimentos , 2003, DOI: 10.1590/S0101-20612003000200007
Abstract: the soluble and insoluble cotyledon (spf-co and ipf-co) and tegument (spf-te and ipf-te) cell wall polymer fractions of common beans (phaseolus vulgaris) were isolated using a chemical-enzymatic method. the sugar composition showed that spf-co was constituted of 38.6% arabinose, 23.4% uronic acids, 12.7% galactose, 11.2% xylose, 6.4% mannose and 6.1% glucose, probably derived from slightly branched and weakly bound polymers. the ipf-co was fractionated with chelating agent (cdta) and with increasing concentrations of naoh. the bulk of the cell wall polymers (29.4%) were extracted with 4.0m naoh and this fraction contained mainly arabinose (55.0%), uronic acid (18.9%), glucose (10.7%), xylose (10.3%) and galactose (3.4%). about 8.7% and 10.6% of the polymers were solubilised with cdta and 0.01m naoh respectively and were constituted of arabinose (52.0 and 45.9%), uronic acids (25.8 and 29.8%), xylose (9.6 and 10.2%), galactose (6.1 and 3.9%) and glucose (6.5 and 3.8%). the cell wall polymers were also constituted of small amounts (5.6 and 7.2%) of cellulose (cel) and of non-extractable cell wall polymers (necw). about 16.8% and 17.2% of the polymers were solubilised with 0.5 and 1.0m naoh and contained, respectively, 92.1 and 90.7% of glucose derived from starch (ist). the neutral sugar and polymers solubilization profiles showed that weakly bound pectins are present mainly in spf-co (water-soluble), cdta and 0.01-0.1m naoh soluble fractions. less soluble, highly cross-linked pectins were solubilised with 4.0m naoh. this pectin is arabinose-rich, probably highly branched and has a higher molecular weight than the pectin present in spf-co, cdta and 0.01-0.1m naoh fractions.
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