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1.
PLoS One ; 15(9): e0239998, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32986776

RESUMO

A variety of traits are necessary for bacterial colonization of the interior of plant hosts, including well-studied virulence effectors as well as other phenotypes contributing to bacterial growth and survival within the apoplast. High-throughput methods such as transposon sequencing (TnSeq) are powerful tools to identify such genes in bacterial pathogens. However, there is little information as to the distinctiveness of traits required for bacterial colonization of different hosts. Here, we utilize randomly barcoded TnSeq (RB-TnSeq) to identify the genes that contribute to the ability of Pseudomonas syringae strain B728a to grow within common bean (Phaseolus vulgaris), lima bean (Phaseolus lunatus), and pepper (Capsicum annuum); species representing two different plant families. The magnitude of contribution of most genes to apoplastic fitness in each of the plant hosts was similar. However, 50 genes significantly differed in their fitness contributions to growth within these species. These genes encoded proteins in various functional categories including polysaccharide synthesis and transport, amino acid metabolism and transport, cofactor metabolism, and phytotoxin synthesis and transport. Six genes that encoded unannotated, hypothetical proteins also contributed differentially to growth in these hosts. The genetic repertoire of a relatively promiscuous pathogen such as P. syringae may thus be shaped, at least in part, by the conditional contribution of some fitness determinants.


Assuntos
Genes Bacterianos , Doenças das Plantas/microbiologia , Infecções por Pseudomonas/microbiologia , Pseudomonas syringae/crescimento & desenvolvimento , Pseudomonas syringae/genética , Proteínas de Bactérias/genética , Sequência de Bases , Capsicum/crescimento & desenvolvimento , Capsicum/microbiologia , Elementos de DNA Transponíveis/genética , Regulação Bacteriana da Expressão Gênica , Phaseolus/crescimento & desenvolvimento , Phaseolus/microbiologia , Filogenia , Pseudomonas syringae/patogenicidade , Virulência/genética
2.
Mol Genet Genomics ; 295(6): 1325-1337, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32607601

RESUMO

The main edible organ of snap bean (Phaseolus vulgaris L.) is the pod, whose color is a main characteristic affecting its commercial use. Golden pods are popular with consumers; however, color instability affects their commercial exploitation and causes economic losses to the planters. In this study, we focused on the different pod color of two varieties of snap bean. The golden yellow color of snap bean pods is controlled by a single recessive nuclear gene located at 1-4.24 Mb of chromosome 2. To explore the physiological and molecular mechanism of the golden pod color, the golden bean line 'A18-1' and the green bean line 'Renaya' were selected as experimental materials. We analyzed the pigment contents, detected the intermediate products of chlorophyll biosynthesis, and identified differentially expressed genes using RNA-seq. The formation of golden bean pods reflects a chlorophyll deficiency, which was speculated to be caused by impairment of the Mg-protoporphyrin IX to chlorophyllide step. In 'A18-1' and 'Renaya' pods on 10, 14, and 18 days, five genes related to this step were differentially expressed, all of which were protochlorophyllide oxidoreductase (POR) genes. Among them, the expression changes of the Phvul. 004G112700, Phvul.007G157500, and Phvul. 004G112400 genes were consistent with the color change and physiological data during pod development in 'A18-1' and 'Renaya'. We speculated that the altered expression of these three POR genes might be related to changes in the chlorophyllide content. The results might provide insight into the understanding of chlorophyll biosynthesis and crop breeding for snap bean.


Assuntos
Clorofila/metabolismo , Regulação da Expressão Gênica de Plantas , Phaseolus/metabolismo , Proteínas de Plantas/metabolismo , Sementes/metabolismo , Vicia faba/metabolismo , Cor , Phaseolus/genética , Phaseolus/crescimento & desenvolvimento , Proteínas de Plantas/genética , Sementes/genética , Sementes/crescimento & desenvolvimento , Transcriptoma , Vicia faba/genética , Vicia faba/crescimento & desenvolvimento
3.
PLoS One ; 15(6): e0234512, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32511280

RESUMO

Nutritional deficiencies limit the growth of snap bean plants, therefore knowing the biological mechanisms involved in it is fundamental. This study is aimed to evaluate the damage caused by a deficiency of macronutrients in physiological variables that cause decreased growth and the appearance of visual symptoms in snap bean. Thus, we design a hydroponic system of snap bean cultivation in order to test the effect of macronutrient deficiencies in a controlled environment. The treatments consisted in evaluate the effects of lack of one macronutrient in time. To perform this, we used Hoagland and Arnon solution in its complete formulation (control) or without N, P; K; Mg, Ca or S in each treatment. Physiological, nutritional, and growth analyses were performed when visual deficiency symptoms of each omitted nutrient appeared. Thus, the omissions of N and P in the nutrient solution led to lower accumulations of all macronutrients in the shoot. And the K, Ca, Mg, and S omissions decreased the amounts of K, Ca, Mg, P, and S in the shoot of the snap bean plants when compared with the plants grown in the complete nutrient solution. With the lowest accumulation of macronutrients, the content of photosynthetic pigments and the photosynthetic rate were reduced, with harmful effects on plant growth. Thus, from the losses in dry matter production of the shoot, the order of limiting of macronutrients in bean plants was N < P < Ca < S < Mg < K, with a decrease of up to 86.2%, 80.1%, 51.2%, 46.5%, 25.6%, and 19.3%, respectively. The nitrogen deficiency is more evident, proven by symptoms such as chlorosis in the lower and upper third leaves and necrosis of the lower third leaves.


Assuntos
Nitrogênio/metabolismo , Nutrientes/metabolismo , Phaseolus/crescimento & desenvolvimento , Fotossíntese/genética , Ambiente Controlado , Hidroponia , Nutrientes/fisiologia , Phaseolus/metabolismo , Folhas de Planta/crescimento & desenvolvimento , Folhas de Planta/metabolismo , Brotos de Planta/crescimento & desenvolvimento , Brotos de Planta/metabolismo , Potássio/metabolismo
4.
PLoS One ; 15(4): e0231150, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32275687

RESUMO

The microbial community in the plant rhizosphere is vital to plant productivity and disease resistance. Alterations in the composition and diversity of species within this community could be detrimental if microbes suppressing the activity of pathogens are removed. Species of the insect-pathogenic fungus, Metarhizium, commonly employed as biological control agents against crop pests, have recently been identified as plant root colonizers and provide a variety of benefits (e.g. growth promotion, drought resistance, nitrogen acquisition). However, the impact of Metarhizium amendment on the rhizosphere microbiome has yet to be elucidated. Using Illumina sequencing, we examined the community profiles (bacteria and fungi) of common bean (Phaseolus vulgaris) rhizosphere (loose soil and plant root) after amendment with M. robertsii conidia, in the presence and absence of an insect host. Although alpha diversity was not significantly affected overall, there were numerous examples of plant growth-promoting organisms that significantly increased with Metarhizium amendment (Bradyrhizobium, Flavobacterium, Chaetomium, Trichoderma). Specifically, the abundance of Bradyrhizobium, a group of nitrogen-fixing bacteria, was confirmed to be increased using a qPCR assay with genus-specific primers. In addition, the ability of the microbiome to suppress the activity of a known bean root pathogen was assessed. The development of disease symptoms after application with Fusarium solani f. sp. phaseoli was visible in the hypocotyl and upper root of plants grown in sterilized soil but was suppressed during growth in microbiome soil and soil treated with M. robertsii. Successful amendment of agricultural soils with biocontrol agents such as Metarhizium necessitates a comprehensive understanding of the effects on the diversity of the rhizosphere microbiome. Such research is fundamentally important towards sustainable agricultural practices to improve overall plant health and productivity.


Assuntos
Metarhizium/fisiologia , Microbiota/fisiologia , Phaseolus/crescimento & desenvolvimento , Doenças das Plantas/imunologia , Rizosfera , Bradyrhizobium/isolamento & purificação , Bradyrhizobium/fisiologia , Proteção de Cultivos/métodos , Resistência à Doença , Fusarium/patogenicidade , Phaseolus/microbiologia , Desenvolvimento Vegetal , Doenças das Plantas/microbiologia , Raízes de Plantas/microbiologia , Microbiologia do Solo , Esporos Fúngicos/fisiologia , Desenvolvimento Sustentável
5.
Plant Physiol Biochem ; 151: 77-87, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32200193

RESUMO

Molybdenum is considered one of the most important micronutrients applied as a foliar fertilizer for common dry bean. In this study, molybdenum oxide nanoparticles (MoO3-NPs) were applied in different concentrations (0, 10, 20, 30 and 40 ppm) over two sequent seasons, 2018 and 2019, to investigate their effect on the plant morphological criteria, yield, and the genomic stability of DNA. The results showed that the application of 40 ppm MoO3-NPs as a foliar fertilizer showed preferable values of plant morphological criteria, such as the number of leaves and branches per plant, as well as the fresh and dry weight with regard to the common bean plant. In addition, the seed yield increased by 82.4% and 84.1% with 40 ppm, while the shoot residue increased by 32.2% and 32.1% with 20 ppm of MoO3-NPs during two seasons, 2018 and 2019, respectively. Furthermore, the common bean treated with 20 and 40 ppm MoO3-NPs had positive unique bands with ISSR primer 848 at 1400 bp (Rf 0.519) and with primer ISSR2M at 200 bp (Rf 0.729), respectively. In addition, SDS-PAGE reveald some proteins in seedlings which were absent in the flowering stage at 154, 102, 64, 37 and 34 KDa, which may be due to differences in plant proteins required for metabolic processes in each stage. In conclusion, the application of 40 ppm MoO3-NPs was more effective on the productivity of the common bean plants.


Assuntos
Fertilizantes , Instabilidade Genômica , Molibdênio/administração & dosagem , Phaseolus/crescimento & desenvolvimento , Phaseolus/genética , DNA de Plantas/genética , Nanopartículas Metálicas , Óxidos/administração & dosagem , Folhas de Planta , Plântula
6.
Sci Rep ; 10(1): 3628, 2020 02 27.
Artigo em Inglês | MEDLINE | ID: mdl-32107403

RESUMO

Common bean variety choice by farmers in Uganda is driven by seed yield plus end-use quality traits like market class and cooking time. Limited genotype by environment information is available for traits valued by consumers. This research evaluated yield, seed size, hydration properties, and cooking time of 15 common bean genotypes within market classes recognized by consumers along with three farmers' checks at nine on-farm locations in Uganda for two seasons. Yield ranged from 71 to 3,216 kg ha-1 and was largely controlled by location (21.5% of Total Sums of Squares [TSS]), plus the interaction between location and season (48.6% of TSS). Cooking time varied from 19 to 271 minutes with the genotypes Cebo Cela and Ervilha consistently cooking fastest in 24 and 27 minutes respectively. Comparatively, the local checks (NABE-4, NABE-15, and Masindi yellow) took 35 to 45 minutes to cook. Cooking time was largely controlled by genotype (40.6% of TSS). A GGE biplot analysis uncovered the presence of two mega-environments for yield and one mega-environment for cooking time. Identification of mega-environments for these traits will help expedite common bean breeding, evaluation, and variety selection through reduction of number of test environments needed for phenotype evaluations. The high yielding and fast cooking genotypes from this study can be targeted as parental materials to improve existing common bean germplasm for these important traits.


Assuntos
Phaseolus/genética , Sementes/química , Cruzamento , Culinária , Fazendas , Interação Gene-Ambiente , Genótipo , Phaseolus/química , Phaseolus/classificação , Phaseolus/crescimento & desenvolvimento , Fenótipo , Sementes/classificação , Sementes/genética , Sementes/crescimento & desenvolvimento , Uganda
7.
Antonie Van Leeuwenhoek ; 113(5): 687-696, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-31900709

RESUMO

Hydrogen-uptake (Hup) activity is implicated in the mitigation of energy losses associated with the biological nitrogen fixation process, and has been related to productivity increases in some legume hosts. However, in common bean (Phaseolus vulgaris L.) the expression of hydrogenase is rare. In this study an 18-kb hup gene cluster from Rhizobium leguminosarum bv. viciae encoding a NiFe hydrogenase was successfully transferred to three common bean rhizobial strains lacking hydrogenase activity (Hup-) but symbiotically very effective and used in commercial inoculants in Brazil: one strain originally from Colombia (Rhizobium tropici CIAT 899), and two strains from Brazil (R. tropici H 12 and Rhizobium freirei PRF 81). The inclusion of NiCl2 in the nutrient solution did not increase hydrogenase activity, indicating that common bean plants allow efficient nickel provision for hydrogenase synthesis in the bacteroids. The symbiotic performance-evaluated by nodulation, plant growth, N accumulation and seed production-of wild-type and Hup+ derivative strains was compared in experiments performed with cultivar Carioca under greenhouse conditions, in sterile substrate and in non-sterile soil. Statistically significant increases in one or more parameters were observed for all three Hup+ derivatives when compared to the respective wild-type strain. Differences were found mainly with the Brazilian strains, reaching impressive increases in nodule efficiency and seed total N content. The results highlight the potential of using Rhizobium Hup+ strains for the design of more energy-efficient inoculants for the common bean crop.


Assuntos
Hidrogenase/genética , Phaseolus , Plantas Geneticamente Modificadas , Rhizobium/genética , Proteínas de Bactérias/genética , Brasil , Genes Bacterianos , Hidrogênio/metabolismo , Nitrogênio/metabolismo , Fixação de Nitrogênio/genética , Phaseolus/crescimento & desenvolvimento , Phaseolus/metabolismo , Phaseolus/microbiologia , Nódulos Radiculares de Plantas/genética , Simbiose/genética
8.
Arch Microbiol ; 202(2): 309-322, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31659382

RESUMO

In northern Mexico, aridity, salinity and high temperatures limit areas that can be cultivated. To investigate the nature of nitrogen-fixing symbionts of Phaseolus filiformis, an adapted wild bean species native to this region, their phylogenies were inferred by MLSA. Most rhizobia recovered belong to the proposed new species Ensifer aridi. Phylogenetic analyses of nodC and nifH show that Mexican isolates carry symbiotic genes acquired through horizontal gene transfer that are divergent from those previously characterized among bean symbionts. These strains are salt tolerant, able to grow in alkaline conditions, high temperatures, and capable of utilizing a wide range of carbohydrates and organic acids as carbon sources for growth. This study improves the knowledge on diversity, geographic distribution and evolution of bean-nodulating rhizobia in Mexico and further enlarges the spectrum of microsymbiont with which Phaseolus species can interact with, including cultivated bean varieties, notably under stressed environments. Here, the species Ensifer aridi sp. nov. is proposed as strain type of the Moroccan isolate LMR001T (= LMG 31426T; = HAMBI 3707T) recovered from desert sand dune.


Assuntos
Phaseolus/metabolismo , Rhizobiaceae/classificação , Rhizobiaceae/isolamento & purificação , Nódulos Radiculares de Plantas/microbiologia , DNA Bacteriano/genética , Temperatura Alta , México , Phaseolus/crescimento & desenvolvimento , Filogenia , RNA Ribossômico 16S/genética , Rhizobiaceae/genética , Tolerância ao Sal/genética , Areia , Análise de Sequência de DNA , Simbiose
9.
J Sci Food Agric ; 100(1): 10-15, 2020 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-31471899

RESUMO

Bean paste is a confectionery ingredient originating in Asia made from cooked beans and sugar. In Japan, bean paste-containing products play an important role in the traditional confectionery industry. Common beans (Phaseolus vulgaris L.) are used for making white bean paste, and the tebou market class is dedicated to white paste production. Bean paste qualities include paste yield, color, stickiness, smoothness, aroma and flavor. High paste yield, whiteness and smoothness are preferred. The ideal stickiness depends on the final product to be made using bean paste. In terms of aroma and flavor, high sweetness and low beaniness are generally desired. Most of the paste qualities can only be measured by preparing bean paste, which is labor intensive and low throughput. Yuki and Kinu tebou bean varieties were developed in this manner because the highest end-use quality is indispensable to domestic varieties. Tebou bean breeding in Japan is at the stage where more research is necessary to develop faster screening methods to predict important paste quality attributes. This review summarizes the literature on research on white bean paste quality and common bean breeding efforts conducted so far written either in English or Japanese, covering: (1) bean paste production and ingredient sources, (2) the selection criteria and methods used by Japanese breeders and (3) the resulting varieties developed for bean paste. © 2019 Society of Chemical Industry.


Assuntos
Doces/análise , Phaseolus/química , Phaseolus/genética , Cruzamento , Humanos , Japão , Valor Nutritivo , Phaseolus/crescimento & desenvolvimento , Controle de Qualidade , Paladar
10.
Nat Genet ; 52(1): 118-125, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31873299

RESUMO

We conducted a large-scale genome-wide association study evaluation of 683 common bean accessions, including landraces and breeding lines, grown over 3 years and in four environments across China, ranging in latitude from 18.23° to 45.75° N, with different planting dates and abiotic or biotic stresses. A total of 505 loci were associated with yield components, of which seed size, flowering time and harvest maturity traits were stable across years and environments. Some loci aligned with candidate genes controlling these traits. Yield components were observed to have strong associations with a gene-rich region on the long arm of chromosome 1. Manipulation of seed size, through selection of seed length versus seed width and height, was deemed possible, providing a genome-based means to select for important yield components. This study shows that evaluation of large germplasm collections across north-south geographic clines is useful in the detection of marker associations that determine grain yield in pulses.


Assuntos
Genética Populacional , Genoma de Planta , Phaseolus/crescimento & desenvolvimento , Phaseolus/genética , Polimorfismo de Nucleotídeo Único , Locos de Características Quantitativas , Mapeamento Cromossômico , Cromossomos de Plantas , Estudo de Associação Genômica Ampla , Genótipo , Fenótipo , Análise de Sequência de DNA
11.
Cells ; 8(11)2019 10 31.
Artigo em Inglês | MEDLINE | ID: mdl-31683651

RESUMO

The membrane phosphoproteome in plant seed changes dynamically during embryo development. We examined the patterns of Phaseolus vulgaris (common bean) seed membrane protein phosphorylation from the mid-maturation stage until two days after germination. Serine and threonine phosphorylation declined during seed maturation while tyrosine phosphorylation remained relatively constant. We discovered that the aquaporin PvTIP3;1 is the primary seed membrane phosphoprotein, and PvTIP3;2 shows a very low level of expression. The level of phosphorylated Ser7 in PvTIP3;1 increased four-fold after seed maturation. Since phosphorylation increases water channel activity, we infer that water transport by PvTIP3;1 is highest in dry and germinating seeds, which would be optimal for seed imbibition. By the use of isoform-specific, polyclonal peptide antibodies, we found that PvTIP3;2 is expressed in a developmental pattern similar to PvTIP3;1. Unexpectedly, PvTIP3;2 is tyrosine phosphorylated following seed maturation, which may suggest a mechanism for the regulation of PvTIP3;2 following seed germination. Analysis of protein secondary structure by circular dichroism spectroscopy indicated that the amino-terminal domain of PvTIP3;1 is generally unstructured, and phosphorylation increases polyproline II (PPII) helical structure. The carboxy-terminal domain also gains PPII character, but in a pH-dependent manner. These structural changes are a first step to understand TIP3 aquaporin regulation.


Assuntos
Aquaporinas/metabolismo , Phaseolus/crescimento & desenvolvimento , Proteínas de Plantas/metabolismo , Aquaporinas/química , Germinação , Concentração de Íons de Hidrogênio , Espectrometria de Massas , Phaseolus/metabolismo , Fosforilação , Fosfotirosina/análise , Proteínas de Plantas/química , Isoformas de Proteínas/química , Isoformas de Proteínas/metabolismo , Estrutura Secundária de Proteína , Sementes/crescimento & desenvolvimento , Sementes/metabolismo , Água/metabolismo
12.
Cienc. tecnol. salud ; 6(2): 98-106, jul dic 2019. ^c27 cmilus
Artigo em Espanhol | LILACS | ID: biblio-1095831

RESUMO

El complejo de mosca blanca (Hemiptera: Aleyrodidae) incluye algunas de las principales plagas del ejote francés (Phaseolus vulgaris L.). Dentro de las cuales, Bemisia tabaci es vector del virus del mosaico dorado que afecta la calidad y rendimiento del cultivo, con pérdidas hasta del 100% y un control difícil debido a la resistencia adquirida por las plagas hacia algunos agroquímicos. El ejote francés ocupa el segundo lugar entre de los productos no tradicionales de exportación de Guatemala. Su manejo agronómico ha sido principalmente a través del control químico, el cual afecta insectos y otros organismos que no son el objetivo del control, tales como: polinizadores, insectos benéficos, humanos y fauna silvestre. Los objetivos del estudio fueron: determinar la presencia de enemigos naturales nativos de la mosca blanca e identificar las especies de mosca blanca presentes en el cultivo del ejote francés en Chimaltenango. Para el estudio se establecieron cuatro parcelas de 300 m², se realizaron muestreos semanales durante dos ciclos del cultivo. En cada parcela se muestrearon cinco sitios y en cada sitio cinco plantas. Las especies de parasitoides nativos encontrados fueron: Encarsia Formosa Gahan, Eretmocerus eremicus Rose y Zolnerowuch y Amitus fuscipennis MacGown y Nebeker, la especie más abundante fue A. fuscipennis. Los depredadores identificados fueron Chrysoperla carnea (Stephens) e Hippodamia convergens Guerin-Meneville. La especie más abundante fue H. convergens. Estas especies podrían ser herramientas valiosas para ser empleadas en programas de control biológico, producciones orgánicas o en programas de manejo integrado de plagas.


The whitefly complex (Hemiptera: Aleyrodidae) includes some of the main pests of the French green bean (Phaseolus vulgaris L.). Among which, Bemisia tabaci is a vector of the golden mosaic virus that affects the quality and yield of the crop, with losses up to 100% and difficult control due to the resistance acquired by pests towards some agrochemicals. The French green bean ranks second among the non-traditional export products of Guatemala. Its agronomic management has been mainly through chemical control, which affects insects and other organisms that are not the objective of the control, such as: pollinators, beneficial insects, humans and wildlife. The objectives of the study were: to determine the presence of natural enemies native to the whitefly and identify the species of whitefly present in the cultivation of the French bean in Chimaltenango. For the study, four 300 m² plots were established, weekly sampling was carried out during two crop cycles. Five sites were sampled on each plot and five plants on each site. The native parasitoid species found were: Encarsia Formosa Gahan, Eretmocerus eremicus Rose and Zolnerowuch and Amitus fuscipennis MacGown and Nebeker, the most abundant species was A. fuscipennis. The predators identified were Chrysoperla carnea (Stephens) and Hippodamia convergens Guerin-Meneville. The most abundant species was H. convergens. These species could be valuable tools to be used in biological control programs, organic productions or in integrated pest management programs.


Assuntos
Animais , Phaseolus/crescimento & desenvolvimento , Phaseolus/parasitologia , Hemípteros/crescimento & desenvolvimento , Hemípteros/parasitologia , Controle Biológico de Vetores/métodos , Vírus do Mosaico
13.
Sci Rep ; 9(1): 15178, 2019 10 23.
Artigo em Inglês | MEDLINE | ID: mdl-31645608

RESUMO

Essential oils (EO) of several plant species have the potential to combat plant and fungal diseases. However, the effects of Achillea millefolium EO on the development of common bean (Phaseolus vulgaris L.), is still unknown. Moreover, its effect on N2-fixing bacteria, and in general on soil properties has not been studied yet. A greenhouse trial was set up to evaluate both the influence that Achillea millefolium EO and the inoculation with three different Rhizobium strains have on the bean plant and on the chemical and microbiological properties of an agriculturally used Cambisol. Non-inoculated pots were used as control. Our findings showed a decrease in bacterial colony forming units due to EO application and an increase following the Rhizobium inoculation compared to the control. The EO application decreased soil basal respiration and activities of dehydrogenase, urease, ß-glucosidase and acid phosphatase. Such effects were stronger with higher oil concentrations. Moreover, the treatments combining Rhizobium inoculation with EO showed a positive effect on nodulation and plant height. Overall, the combined application of Achillea millefolium EO and rhizobia works as an efficient biocide that could be applied in organic agriculture without hampering the activity of nodule-forming N-fixing bacteria and the development of common bean.


Assuntos
Achillea/química , Óleos Voláteis/farmacologia , Phaseolus/crescimento & desenvolvimento , Extratos Vegetais/farmacologia , Rhizobium/fisiologia , Microbiologia do Solo , Solo/química , Análise de Variância , Phaseolus/efeitos dos fármacos , Phaseolus/enzimologia
14.
J Food Sci ; 84(11): 3179-3185, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31589337

RESUMO

The present work studied, for the first time, the effect of two technologies on the hydration and germination process of beans: ionizing irradiation and ultrasound. In addition, this work proposed a possible biological effect of ultrasound to describe its effect on grain hydration. Carioca beans were irradiated at doses of 2.3 and 3.8 kGy using γ-rays, establishing different metabolic activities for the beans. Then, they were hydrated with and without the ultrasound technology (91 W/L and 25 kHz) at 25 °C. Both the hydration and germination kinetics were evaluated considering the application of both technologies alone and in combination. As results, irradiation did not significantly affect (P > 0.05) the hydration rate, the equilibrium moisture, or the lag phase time, but ultrasound affected them, reducing 50% of the processing time. On the other hand, only the equilibrium moisture was slightly reduced by the interactive effect of irradiation and ultrasound technology, which was discussed based on different metabolism levels. Furthermore, the germination process of carioca bean was hindered by both the studied variables, reducing its germination capacity to 0% in some cases. Therefore, by studying the effect of ultrasound on beans with different active metabolism (due to different irradiation doses), it was suggested that both physical and biological mechanisms are involved during hydration process and that both can be affected by ultrasound. Further, irradiation could be used on carioca beans with objectives such as avoid germination, insects, and microorganism's growth, without an important effect on the hydration kinetics. PRACTICAL APPLICATION: Ultrasound technology has demonstrated to accelerate the soaking process of several legume grains. However, sometimes, grains are irradiated for disinfestation purpose to improve their shelf life. Indeed, irradiation can change the grain properties as the cooking time, hydration time, and germination capacity. Therefore, this work verified if irradiation changes the desirable effect of ultrasound on grain processing: soaking and germination. Moreover, this work novelty is also based on describing the phenomena: by proposing a possible biological effect, further approaches to improve the grain processing can be achieved.


Assuntos
Germinação/efeitos da radiação , Phaseolus/efeitos da radiação , Sementes/crescimento & desenvolvimento , Culinária , Raios gama , Temperatura Alta , Cinética , Phaseolus/química , Phaseolus/crescimento & desenvolvimento , Phaseolus/metabolismo , Sementes/química , Sementes/metabolismo , Sementes/efeitos da radiação , Ultrassom , Água/análise , Água/metabolismo
15.
Appl Environ Microbiol ; 85(24)2019 12 15.
Artigo em Inglês | MEDLINE | ID: mdl-31562174

RESUMO

We studied symbiotic performance of factorial combinations of diverse rhizobial genotypes (GR) and East African common bean varieties (GL) that comprise Andean and Mesoamerican genetic groups. An initial wide screening in modified Leonard jars (LJ) was followed by evaluation of a subset of strains and genotypes in pots (contained the same, sterile medium) in which fixed nitrogen was also quantified. An additive main effect and multiplicative interaction (AMMI) model was used to identify the contribution of individual strains and plant genotypes to the GL × GR interaction. Strong and highly significant GL × GR interaction was found in the LJ experiment but with little evidence of a relation to genetic background or growth habits. The interaction was much weaker in the pot experiment, with all bean genotypes and Rhizobium strains having relatively stable performance. We found that R. etli strain CFN42 and R. tropici strains CIAT899 and NAK91 were effective across bean genotypes but with the latter showing evidence of positive interaction with two specific bean genotypes. This suggests that selection of bean varieties based on their response to inoculation is possible. On the other hand, we show that symbiotic performance is not predicted by any a priori grouping, limiting the scope for more general recommendations. The fact that the strength and pattern of GL × GR depended on growing conditions provides an important cautionary message for future studies.IMPORTANCE The existence of genotype-by-strain (GL × GR) interaction has implications for the expected stability of performance of legume inoculants and could represent both challenges and opportunities for improvement of nitrogen fixation. We find that significant genotype-by-strain interaction exists in common bean (Phaseolus vulgaris L.) but that the strength and direction of this interaction depends on the growing environment used to evaluate biomass. Strong genotype and strain main effects, combined with a lack of predictable patterns in GL × GR, suggests that at best individual bean genotypes and strains can be selected for superior additive performance. The observation that the screening environment may affect experimental outcome of GL × GR means that identified patterns should be corroborated under more realistic conditions.


Assuntos
Genótipo , Phaseolus/genética , Phaseolus/microbiologia , Rhizobium tropici/genética , Pool Gênico , Nitrogênio , Fixação de Nitrogênio , Phaseolus/crescimento & desenvolvimento , Filogenia , Nodulação , Rhizobium/classificação , Rhizobium/genética , Rhizobium/metabolismo , Rhizobium tropici/classificação , Rhizobium tropici/metabolismo , Simbiose/genética
16.
Artigo em Inglês | MEDLINE | ID: mdl-31480525

RESUMO

Poor soil health is a critical problem in many urban landscapes. Degraded soil restricts plant growth and microorganism activity, limiting the ability of urban landscapes to perform much needed ecosystem services. Incorporation of approximately 33% compost by volume into degraded soil has been proven to improve soil health and structure over time while avoiding the financial and environmental costs of importing soil mixes from elsewhere. However, additions of high volumes of compost could potentially increase the risk of nutrient loss through leaching and runoff. The objective of our study was to consider the effects of different compost amendments on soil health, plant health and susceptibility to nutrient leaching in order to identify ranges of acceptable compost characteristics that could be used for soil remediation in the urban landscape. A bioassay was conducted with Phaseolus vulgaris (Bush Bean) to measure the effect of nine composts from different feedstocks on various plant health parameters. Leachate was collected prior to planting to measure nutrient loss from each treatment. All compost amendments were found to improve soil health. Nutrient-rich, manure-based composts produced the greatest plant growth, but also leached high concentrations of nitrate and phosphorus. Some treatments provided sufficient nutrients for plant growth without excess nutrient loss. When incorporating as much as 33% compost by volume into a landscape bed, the optimal compost will generally have a C:N ratio of 10-20, P-content <1.0% and a soluble salt content between 1.0 and 3.5 mmhos/cm. These recommendations should ensure optimal plant and soil health and minimize nutrient leaching.


Assuntos
Compostagem/normas , Recuperação e Remediação Ambiental , Phaseolus/crescimento & desenvolvimento , Poluentes do Solo/análise , Solo/química , Cidades , Ecossistema , Esterco , Fósforo/análise
17.
J Sci Food Agric ; 99(13): 6049-6059, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31342530

RESUMO

BACKGROUND: The scarcity of irrigation water is severely affecting global crop production. In this context, biostimulants are increasingly used as alternatives means against abiotic stress conditions. In this study, phenolic compounds composition and bioactive properties of common bean (Phaseolus vulgaris L.) plants grown under water stress conditions and biostimulants application were investigated. RESULTS: Sixteen individual phenolic compounds were detected in both pods and seeds with a notable difference in their compositional profile. A significant effect on phenolic compounds content and composition was also observed for the biostimulants tested. Regarding the antibacterial activity, pods of the second harvest and seed extracts showed significant efficacy against Bacillus cereus, especially in water-stressed plants, where all biostimulant treatments were more effective than positive controls. Moreover, all biostimulant treatments for seed extracts of water-stressed plants were more effective against Staphylococcus aureus compared with ampicillin, whereas streptomycin showed the best results. Extracts from pods of the second harvest from normally irrigated plants showed the best results against the fungi tested, except for Penicillium verrucosum var. cyclopium. Finally, no significant cytotoxic effects were detected. CONCLUSION: In conclusion, the biostimulants tested increased total phenolic compounds content compared with control treatment, especially in pods of the first harvest and seeds of water-stressed plants. Moreover, bioactive properties showed a varied response in regard to irrigation and biostimulant treatment. Therefore, biostimulants can be considered as a useful means towards increasing phenolic compounds content, and they may also affect the antimicrobial properties of pods and seeds extracts. © 2019 Society of Chemical Industry.


Assuntos
Desidratação , Phaseolus/química , Phaseolus/fisiologia , Fenóis/farmacologia , Extratos Vegetais/farmacologia , Água/metabolismo , Bacillus cereus/efeitos dos fármacos , Bacillus cereus/crescimento & desenvolvimento , Phaseolus/crescimento & desenvolvimento , Phaseolus/microbiologia , Fenóis/química , Fenóis/metabolismo , Extratos Vegetais/química , Extratos Vegetais/metabolismo , Sementes/química , Sementes/crescimento & desenvolvimento , Sementes/metabolismo , Sementes/microbiologia , Staphylococcus aureus/efeitos dos fármacos , Staphylococcus aureus/crescimento & desenvolvimento , Estresse Fisiológico , Água/análise
18.
J Vis Exp ; (149)2019 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-31305517

RESUMO

Robot systems are actively researched for manipulation of natural plants, typically restricted to agricultural automation activities such as harvest, irrigation, and mechanical weed control. Extending this research, we introduce here a novel methodology to manipulate the directional growth of plants via their natural mechanisms for signaling and hormone distribution. An effective methodology of robotic stimuli provision can open up possibilities for new experimentation with later developmental phases in plants, or for new biotechnology applications such as shaping plants for green walls. Interaction with plants presents several robotic challenges, including short-range sensing of small and variable plant organs, and the controlled actuation of plant responses that are impacted by the environment in addition to the provided stimuli. In order to steer plant growth, we develop a group of immobile robots with sensors to detect the proximity of growing tips, and with diodes to provide light stimuli that actuate phototropism. The robots are tested with the climbing common bean, Phaseolus vulgaris, in experiments having durations up to five weeks in a controlled environment. With robots sequentially emitting blue light-peak emission at wavelength 465 nm-plant growth is successfully steered through successive binary decisions along mechanical supports to reach target positions. Growth patterns are tested in a setup up to 180 cm in height, with plant stems grown up to roughly 250 cm in cumulative length over a period of approximately seven weeks. The robots coordinate themselves and operate fully autonomously. They detect approaching plant tips by infrared proximity sensors and communicate via radio to switch between blue light stimuli and dormant status, as required. Overall, the obtained results support the effectiveness of combining robot and plant experiment methodologies, for the study of potentially complex interactions between natural and engineered autonomous systems.


Assuntos
Luz , Phaseolus/crescimento & desenvolvimento , Desenvolvimento Vegetal/efeitos da radiação , Robótica , Estimulação Luminosa
19.
PLoS One ; 14(6): e0217099, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31170187

RESUMO

Drought substantially limits seed yield of common bean (Phaseolus vulgaris L.) in the tropics. Understanding the interaction of drought on yield and the nutrient concentration of the seed is vital in order to supply nutrition to the millions of consumers who rely on common bean as a staple crop. Nevertheless, the impact of drought on common bean for both yield and nutrient concentration has not yet been concurrently investigated in a field environment. Using 10 bred lines developed by CIAT and its partners for their improved adaptation to drought and phosphorus deficiency, this study characterised the impact of drought on yield and nutrient concentration for leaf and seed tissue of common bean grown in the field. Drought significantly reduced leaf area (by ~50%), harvest index (by ~60%), yield (by ~70%), seed weight (by ~25%) and enriched carbon isotope abundance (δ13C) in the seed. Within the soluble leaf fraction, drought significantly decreased the concentration of mineral nutrients and amino acids, whereas no negative effect on the concentration of nutrients and amino acids was detected within the seed. Genotypic variation in nutrient concentration in both the leaf and seed tissue was identified and should be explored further to identify traits that may confer tolerance to abiotic stress.


Assuntos
Secas , Qualidade dos Alimentos , Valor Nutritivo , Phaseolus/crescimento & desenvolvimento , Phaseolus/metabolismo , Sementes/metabolismo , Aminoácidos/metabolismo , Açúcares/metabolismo
20.
Planta ; 250(4): 1281-1292, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31240396

RESUMO

MAIN CONCLUSION: Cyanogenic glycosides present in the seeds of wild lima bean plants are associated with seedling defense but do not affect seed germination and seedling growth. Wild lima bean plants contain cyanogenic glycosides (CNGs) that are known to defend the plant against leaf herbivores. However, seed feeders appear to be unaffected despite the high levels of CNGs in the seeds. We investigated a possible role of CNGs in seeds as nitrogen storage compounds that influence plant growth, as well as seedling resistance to herbivores. Using seeds from four different wild lima bean natural populations that are known to vary in CNG levels, we tested two non-mutually exclusive hypotheses: (1) seeds with higher levels of CNGs produce seedlings that are more resistant against generalist herbivores and, (2) seeds with higher levels of CNGs germinate faster and produce plants that exhibit better growth. Levels of CNGs in the seeds were negatively correlated with germination rates and not correlated with seedling growth. However, levels of CNGs increased significantly soon after germination and seeds with the highest CNG levels produced seedlings with higher CNG levels in cotyledons. Moreover, the growth rate of the generalist herbivore Spodoptera littoralis was lower in cotyledons with high-CNG levels. We conclude that CNGs in lima bean seeds do not play a role in seed germination and seedling growth, but are associated with seedling defense. Our results provide insight into the potential dual function of plant secondary metabolites as defense compounds and storage molecules for growth and development.


Assuntos
Glicosídeos/metabolismo , Phaseolus/química , Imunidade Vegetal , Spodoptera/fisiologia , Animais , Germinação , Herbivoria , Nitrogênio/metabolismo , Phaseolus/crescimento & desenvolvimento , Phaseolus/imunologia , Phaseolus/parasitologia , Folhas de Planta/genética , Folhas de Planta/crescimento & desenvolvimento , Folhas de Planta/imunologia , Folhas de Planta/parasitologia , Metabolismo Secundário , Plântula/genética , Plântula/crescimento & desenvolvimento , Plântula/imunologia , Plântula/fisiologia , Sementes/química , Sementes/crescimento & desenvolvimento , Sementes/imunologia , Sementes/parasitologia
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