Screening for Drought Tolerance in Tepary and Common Bean Based on Osmotic Potential Assays

Charcoal rot caused by Macrophomina phaseolina is a common disease of many crops including common bean and soybean. Incidence and severity of charcoal rot are enhanced when plants are drought stressed. Resistance to this pathogen in some common bean genotypes was associated with drought tolerance. Resistance to M. phaseolina among soybean genotypes has not been identified, although a few have been rated moderately resistant based on less root tissue colonization by this pathogen compared to other genotypes. A few soybean genotypes have been rated as slow-wilt or drought-tolerant. The reaction of drought-tolerant soybean to M. phaseolina compared to intolerant or drought-sensitive genotypes has not been determined. Our objective was to determine if there were differences in root colonization by M. phaseolina between drought-tolerant and drought-sensitive soybean genotypes. Drought tolerance of the soybean genotypes and root colonization by M. phaseolina at the R6 and R8 stages of growth were not related in this study. Some drought-tolerant soybean genotypes may resist root colonization by M. phaseolina, but our results suggest that this is not true for all drought-tolerant genotypes. Accepted for publication 21 March 2008. Published 18 June 2008.

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Responses of Parameters for Electrical Impedance Spectroscopy and Pressure–Volume Curves to Drought Stress in Pinus bungeana Seedlings

Forests ◽

10.3390/f11030359 ◽

2020 ◽

Vol 11 (3) ◽

pp. 359

Author(s):

Ai-Fang Wang ◽

Bao Di ◽

Tapani Repo ◽

Marja Roitto ◽

Gang Zhang

Keyword(s):

Drought Stress ◽

Impedance Spectroscopy ◽

Drought Tolerance ◽

Osmotic Potential ◽

Electrical Impedance ◽

Electrical Impedance Spectroscopy ◽

Tree Seedlings ◽

Intracellular Resistance ◽

Pinus Bungeana ◽

Extracellular Resistance

Background and Objectives: Drought occurs more frequently in Northern China with the advent of climate change, which might increase the mortality of tree seedlings after afforestation due to hydraulic failure. Therefore, investigating water relations helps us understand the drought tolerance of tree seedlings. Electrical impedance spectroscopy (EIS) is widely used to assess the responses of plant tissues to stress factors and may potentially reveal the water relations of cells. The aim of this study is to reveal the relationships between EIS and water related parameters, produced by pressure–volume (PV) curves in lacebark pine (Pinus bungeana Zucc.) seedlings reacting to drought stress. Materials and Methods: Four-year-old pot seedlings were divided into three parts (0, 5, and 10 days of drought) before planting, the treated seedlings were then replanted, and finally exposed to post-planting drought treatments with the following soil relative water contents: (i) adequate irrigation (75%–80%), (ii) light drought (55%–60%), (iii) moderate drought (35%–40%), and (iv), severe drought (15%–20%). During the post-planting growth phase, the EIS parameters of needles and shoots, and the parameters of PV curves, were measured coincidently; thus, the correlations between them could be obtained. Results: The extracellular resistance (re) of needles and shoots were substantially reduced after four weeks of severe post-planting drought stress. Meanwhile, the osmotic potential at the turgor-loss point (ψtlp) and the saturation water osmotic potential (ψsat) of shoots decreased after drought stress, indicating an osmotic adjustment in acclimating to drought. The highest correlations were found between the intracellular resistance (ri) of the shoots and ψtlp and ψsat. Conclusions: EIS parameters can be used as a measure of drought tolerance. The change in intracellular resistance is related to the osmotic potential of the cell and cell wall elasticity. Extracellular resistance is a parameter that shows cell membrane damage in response to drought stress in lacebark pine seedlings.

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Evaluation of common bean genotypes for drought tolerance

Bragantia ◽

10.1590/1678-4499.2018002 ◽

2019 ◽

Vol 78 (1) ◽

pp. 1-11 ◽

Cited By ~ 5

Author(s):

Tamires Ribeiro ◽

Daiana Alves da Silva ◽

José Antônio de Fátima Esteves ◽

Cleber Vinicius Giaretta Azevedo ◽

João Guilherme Ribeiro Gonçalves ◽

...

Keyword(s):

Drought Tolerance ◽

Common Bean

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Combining Ability for Agromorphological and Physiological Traits in Different Gene Pools of Common Bean Subjected to Water Deficit

Agronomy ◽

10.3390/agronomy9070371 ◽

2019 ◽

Vol 9 (7) ◽

pp. 371 ◽

Cited By ~ 2

Author(s):

Isabella Mendonça Arruda ◽

Vânia Moda-Cirino ◽

Alessandra Koltun ◽

Douglas Mariani Zeffa ◽

Getúlio Takashi Nagashima ◽

...

Keyword(s):

Water Stress ◽

Drought Tolerance ◽

Grain Yield ◽

Common Bean ◽

Water Deficit ◽

Seed Quality ◽

Plant Performance ◽

Physiological Traits ◽

Gene Pools ◽

Group I

Water stress is one of the main limiting factors for common bean crops, negatively affecting grain yield and seed quality. Thus, the objective of this study was to evaluate the inheritance of agromorphological and physiological traits related to drought tolerance in order to identify promising combinations. The experiment was carried out in a greenhouse with a partial diallel scheme between three drought-tolerant genotypes (IAPAR 81, BAT 477. and SEA 5), and nine cultivars widely grown in Brazil (BRS Estilo, IAC Alvorada, IPR Campos Gerais, IPR Uirapuru, IPR Nhambu, BRS Esteio, IPR Garça, BRS Radiante, and DRK 18), in a randomized block design with four replicates. The plants were grown in pots with substrate under 80% of pot capacity until they reached the stage R5, when water supply was restricted to 30% for 20 days in the pots under stress treatment. A wide variability for the agromorphological and physiological traits was observed. Water deficit reduced plant performance for most agromorphological traits and altered their physiological metabolism. Additive and non-additive effects are involved in the genetic control of the majority of agromorphological and physiological traits both under water stress and control (well-watered) conditions. The parental genotypes BAT 477 (group I) and IAC Alvorada, IPR Uirapuru, and BRS Esteio (group II) may be included in breeding programs aiming at improving drought tolerance in common bean since they present high positive general combining abilities for agromorphological traits. The crosses IAPAR 81 × IPR Campos Gerais, and SEA 5 × BRS Radiante resulted in the best combinations considering grain yield per plant and total dry biomass, when cultivated under water deficit.

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Genome-wide transcriptional changes triggered by water deficit on a drought-tolerant common bean cultivar

BMC Plant Biology ◽

10.1186/s12870-020-02664-1 ◽

2020 ◽

Vol 20 (1) ◽

Cited By ~ 1

Author(s):

Josefat Gregorio Jorge ◽

Miguel Angel Villalobos-López ◽

Karen Lizeth Chavarría-Alvarado ◽

Selma Ríos-Meléndez ◽

Melina López-Meyer ◽

...

Keyword(s):

Cell Wall ◽

Drought Tolerance ◽

Common Bean ◽

Crop Production ◽

Molecular Mechanisms ◽

Molecular Data ◽

Transcriptional Level ◽

Cell Periphery ◽

Enriched Categories ◽

Drought Tolerant

Abstract Background Common bean (Phaseolus vulgaris L.) is a relevant crop cultivated over the world, largely in water insufficiency vulnerable areas. Since drought is the main environmental factor restraining worldwide crop production, efforts have been invested to amend drought tolerance in commercial common bean varieties. However, scarce molecular data are available for those cultivars of P. vulgaris with drought tolerance attributes. Results As a first approach, Pinto Saltillo (PS), Azufrado Higuera (AH), and Negro Jamapa Plus (NP) were assessed phenotypically and physiologically to determine the outcome in response to drought on these common bean cultivars. Based on this, a Next-generation sequencing approach was applied to PS, which was the most drought-tolerant cultivar to determine the molecular changes at the transcriptional level. The RNA-Seq analysis revealed that numerous PS genes are dynamically modulated by drought. In brief, 1005 differentially expressed genes (DEGs) were identified, from which 645 genes were up-regulated by drought stress, whereas 360 genes were down-regulated. Further analysis showed that the enriched categories of the up-regulated genes in response to drought fit to processes related to carbohydrate metabolism (polysaccharide metabolic processes), particularly genes encoding proteins located within the cell periphery (cell wall dynamics). In the case of down-regulated genes, heat shock-responsive genes, mainly associated with protein folding, chloroplast, and oxidation-reduction processes were identified. Conclusions Our findings suggest that secondary cell wall (SCW) properties contribute to P. vulgaris L. drought tolerance through alleviation or mitigation of drought-induced osmotic disturbances, making cultivars more adaptable to such stress. Altogether, the knowledge derived from this study is significant for a forthcoming understanding of the molecular mechanisms involved in drought tolerance on common bean, especially for drought-tolerant cultivars such as PS.

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