Dataset Information

Spatial-temporal analysis of polyethylene glycol-reduced aluminium accumulation and xyloglucan endotransglucosylase action in root tips of common bean (Phaseolus vulgaris).

ABSTRACT:

Background and aims

Aluminium (Al) toxicity and drought are two major limiting factors for common bean (Phaseolus vulgaris) production on tropical acid soils. Polyethylene glycol (PEG 6000)-induced osmotic stress (OS) simulating drought stress reduces Al accumulation in the entire root tips of common bean by alteration of cell-wall (CW) porosity, which might be regulated by two genes encoding xyloglucan endotransglucosylase/hydrolase, PvXTH9 and PvXTHb The aim of this research was to understand the spatial and temporal regulation of both XTH genes in PEG-mediated Al accumulation in the root tips.

Methods

In this study the spatial and temporal expression patterns of Al-inhibited root elongation, Al accumulation, XTH gene expression and xyloglucan endotransglucosylase (XET) enzyme action in the root tips were analysed under PEG-induced OS by a combination of physiological and molecular approaches such as quantitative reverse transcription-polymerase chain reaction (qRT-PCR) and in situ fluorescence detection of XET in root tips.

Key results

The results showed that Al accumulation, expression of XTH genes and XET action were distinctly reduced in the apical 0-2, 2-7 and 7-12?mm zones under OS, implying a potential regulatory role of XTH genes and XET enzyme in CW Al accumulation in these zones.

Conclusions

The results provide novel insights into the physiological and molecular mechanisms of CW structure modification as a response of plant roots to OS, which will contribute to mitigate Al and drought stresses, severely limiting crop yields on acid soils.

SUBMITTER: Zhang M

PROVIDER: S-EPMC4934392 | biostudies-literature | 2016 Jul

REPOSITORIES: biostudies-literature

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Publications

Spatial-temporal analysis of polyethylene glycol-reduced aluminium accumulation and xyloglucan endotransglucosylase action in root tips of common bean (Phaseolus vulgaris).

Zhang Maolin M Ma Yanqi Y Horst Walter J WJ Yang Zhong-Bao ZB

Annals of botany 20160422 1

<h4>Background and aims</h4>Aluminium (Al) toxicity and drought are two major limiting factors for common bean (Phaseolus vulgaris) production on tropical acid soils. Polyethylene glycol (PEG 6000)-induced osmotic stress (OS) simulating drought stress reduces Al accumulation in the entire root tips of common bean by alteration of cell-wall (CW) porosity, which might be regulated by two genes encoding xyloglucan endotransglucosylase/hydrolase, PvXTH9 and PvXTHb The aim of this research was to und ...[more]

PMID: 27106549

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Project description:BACKGROUND:Wild crop relatives have been potentially subjected to stresses on an evolutionary time scale prior to domestication. Among these stresses, drought is one of the main factors limiting crop productivity and its impact is likely to increase under current scenarios of global climate change. We sought to determine to what extent wild common bean (Phaseolus vulgaris) exhibited adaptation to drought stress, whether this potential adaptation is dependent on the climatic conditions of the location of origin of individual populations, and to what extent domesticated common bean reflects potential drought adaptation. METHODS:An extensive and diverse set of wild beans from across Mesoamerica, along with a set of reference Mesoamerican domesticated cultivars, were evaluated for root and shoot traits related to drought adaptation. A water deficit experiment was conducted by growing each genotype in a long transparent tube in greenhouse conditions so that root growth, in addition to shoot growth, could be monitored. RESULTS:Phenotypic and landscape genomic analyses, based on single-nucleotide polymorphisms, suggested that beans originating from central and north-west Mexico and Oaxaca, in the driest parts of their distribution, produced more biomass and were deeper-rooted. Nevertheless, deeper rooting was correlated with less root biomass production relative to total biomass. Compared with wild types, domesticated types showed a stronger reduction and delay in growth and development in response to drought stress. Specific genomic regions were associated with root depth, biomass productivity and drought response, some of which showed signals of selection and were previously related to productivity and drought tolerance. CONCLUSIONS:The drought tolerance of wild beans consists in its stronger ability, compared with domesticated types, to continue growth in spite of water-limited conditions. This study is the first to relate bean response to drought to environment of origin for a diverse selection of wild beans. It provides information that needs to be corroborated in crosses between wild and domesticated beans to make it applicable to breeding programmes.

Dataset Information

Spatial-temporal analysis of polyethylene glycol-reduced aluminium accumulation and xyloglucan endotransglucosylase action in root tips of common bean (Phaseolus vulgaris).

Background and aims

Methods

Key results

Conclusions

Publications

Spatial-temporal analysis of polyethylene glycol-reduced aluminium accumulation and xyloglucan endotransglucosylase action in root tips of common bean (Phaseolus vulgaris).

Similar Datasets

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