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Stephanie J. Watts‐Williams Timothy R. Cavagnaro Stephen D. Tyerman 《Plant, cell & environment》2019,42(1):285-294
Association with arbuscular mycorrhizal fungi (AMF) can impact on plant water relations; mycorrhizal plants can exhibit increased stomatal conductance (gs) and root hydraulic conductance (normalized to root dry weight, Lo), and altered expression of aquaporins (AQP). Many factors regulate such responses; however, plant intraspecific diversity effects have yet to be explored. Twenty geographically diverse accessions of Medicago truncatula were inoculated with the AMF Funneliformis mosseae or mock‐inoculated, and grown under well‐watered conditions. Biomass, gs, shoot nutrient concentrations and mycorrhizal colonization were measured in all accessions, and Lo and gene expression in five accessions. The diverse accessions varied in physiology and gene expression; some accessions were also larger or had higher gs when colonized by F. mosseae. In the five accessions, Lo was higher in two accessions when colonized by AMF and also maintained within a much smaller range than the mock‐inoculated plants. Expression of MtPIP1 correlated with both gs and Lo, and when plants were more than 3% colonized, mycorrhizal colonization correlated with Lo. Accession and AMF treatments had profound effects on M. truncatula, including several measures of plant water relations. Correlations between response variables, especially between molecular and physiological variables, across genotypes, highlight the findings of this study. 相似文献
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Functional diversity of arbuscular mycorrhizas extends to the expression of plant genes involved in P nutrition 总被引:19,自引:0,他引:19
This study of functional diversity considers symbiotic associations between two plant species, Medicago truncatula and Lycopersicon esculentum, and seven species of arbuscular mycorrhizal fungi (AMF). The objective was to integrate physiological analyses with molecular techniques to test whether functional diversity between AMF species is not only apparent at the level of mycorrhiza formation, plant nutrient uptake and plant growth, but also at the molecular level as observed by variation in the root expression of plant genes involved in the plant's P-starvation response. The seven species of AMF varied widely in their influence on the root expression of MtPT2 and Mt4 from M. truncatula and LePT1 and TPSI1 from L. esculentum. At one extreme was Glomus mosseae, whereby its colonization of M. truncatula resulted in the greatest reduction in MtPT2 and Mt4 gene expression and the highest level of P uptake and growth, while at the other extreme was Gigaspora rosea, whereby colonization resulted in the highest levels of MtPT2 and Mt4 gene expression and the lowest P uptake and growth. The expression of LePT1 and TPSI1 within the roots of L. esculentum was low and relatively uniform across the seven mycorrhizas, reflecting the ability of this cultivar to maintain low and constant shoot P levels despite root colonization by a broad selection of AMF. This study extends current understanding of functional diversity and shows that plants can respond differently to AMF, not only at the level of colonization, nutrient uptake and growth, but also at the level of gene expression. 相似文献
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Colonization of two plant species by Glomus intraradices was studied to investigate the two morphological types (Arum and Paris), their symbiotic interfaces and metabolic activities. Root pieces and sections were stained to observe the colonization and metabolic activity of all mycorrhizal structures. There were no growth responses observed in the plants caused by mycorrhizal symbiosis. The two morphological types had a similar percentage of root colonized, but the Arum-type had higher metabolic activity. Most of the mycorrhizal structures (88%) showed succinate dehydrogenase activity; about half showed acid phosphatase activity; and a small percentage showed alkaline phosphatase activity. Phosphatase activity was highest in arbuscules and low in intercellular hyphae in the Arum-type colonization. In the Paris-type, hyphal coils and arbusculate coils showed a similar intermediate percentage of phosphatase activity. We conclude that acid phosphatase is more important than alkaline phosphatase in both colonization types. We discuss the possibility that, whereas arbuscules in Arum-type are the main site for phosphorus release to the host plant, both the hyphal and arbusculate coils may be involved in the Paris-type. 相似文献
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Tatsuhiro Ezawa Timothy R. Cavagnaro Sally E. Smith F. Andrew Smith Ryo Ohtomo 《The New phytologist》2004,161(2):387-392
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Watts-Williams Stephanie J. Tyerman Stephen D. Cavagnaro Timothy R. 《Plant and Soil》2017,420(1-2):375-388
Plant and Soil - Colonisation of roots by arbuscular mycorrhizal fungi (AMF) can increase plant biomass and nutrition under soil zinc (Zn) deficiency and toxicity conditions, but the genes and... 相似文献
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Andrea M. Quiroga Federico J. Berli Daniela Moreno Juan B. Cavagnaro Rubén Bottini 《Journal of Plant Growth Regulation》2009,28(1):28-35
In many cultivars of Vitis vinifera periods of mild water stress during ripening are thought to increase grape quality for winemaking, even though yields may
be negatively affected. Because abscisic acid (ABA) is involved in the signaling of water stress in plants, we examine the
effects of the ABA signal being given without the concomitant water stress. ABA at 250 mg l−1 was sprayed weekly or biweekly from bud-burst until harvest onto the leaves of vineyard-grown plants of cv. Cabernet Sauvignon.
For ABA-treated plants berry yield per bunch and per plant was significantly increased (1.5- to 2.0-fold) across three consecutive
harvests (2005 through 2007). Number of berries per bunch and per plant was the primary basis for the significant crop increases,
although bunches per plant also tended to increase (1.1- to 1.3-fold) across all three harvests. Other parameters assessed
included number of internodes, shoot length, leaf area, leaf water potential at midday, photosynthesis, and stomatal conductance.
These parameters showed no significant change with ABA treatment, although shoot length tended to be reduced, as was leaf
area relative to control plants. The significantly increased fruit yields were thus accomplished without accompanying increases
in leaf photosynthesis and leaf areas. Juice at harvest had equal levels of sugars (Brix) and somewhat higher levels of anthocyanins
and total polyphenols relative to control values. The two latter trends continued for the resultant wine across two vintage
years. In conclusion, three seasons of experimental trials have demonstrated that ABA application can significantly enhance
yield per plant in the field-grown grape (cv. Cabernet Sauvignon) by favoring increased berry set without diminishing the
quality of the fruit for winemaking use. 相似文献
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Pablo F. Cavagnaro Sang-Min Chung Marek Szklarczyk Dariusz Grzebelus Douglas Senalik Anne E. Atkins Philipp W. Simon 《Molecular genetics and genomics : MGG》2009,281(3):273-288
Carrot is the most economically important member of the Apiaceae family and a major source of provitamin A carotenoids in
the human diet. However, carrot molecular resources are relatively underdeveloped, hampering a number of genetic studies.
Here, we report on the synthesis and characterization of a bacterial artificial chromosome (BAC) library of carrot. The library
is 17.3-fold redundant and consists of 92,160 clones with an average insert size of 121 kb. To provide an overview of the
composition and organization of the carrot nuclear genome we generated and analyzed 2,696 BAC-end sequences (BES) from nearly
2,000 BACs, totaling 1.74 Mb of BES. This analysis revealed that 14% of the BES consists of known repetitive elements, with
transposable elements representing more than 80% of this fraction. Eleven novel carrot repetitive elements were identified,
covering 8.5% of the BES. Analysis of microsatellites showed a comparably low frequency for these elements in the carrot BES.
Comparisons of the translated BES with protein databases indicated that approximately 10% of the carrot genome represents
coding sequences. Moreover, among eight dicot species used for comparison purposes, carrot BES had highest homology to protein-coding
sequences from tomato. This deep-coverage library will aid carrot breeding and genetics.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users.
Nucleotide sequence data reported are available in the DDBJ/EMBL/GenBank databases under the accession numbers FJ147695–FJ150390. 相似文献
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Pauline L. Martin William Breslin Meredith Rocca David Wright Joy Cavagnaro 《Birth defects research. Part B, Developmental and reproductive toxicology》2009,86(3):176-203
This report discusses the principles of developmental and reproductive toxicity (DART) testing for biopharmaceuticals. Biopharmaceuticals are large-molecular-weight proteins or peptides produced by modern biotechnology techniques incorporating genetic engineering and hybridoma technologies. The principles of DART testing for biopharmaceuticals are similar to those for small-molecule pharmaceuticals and in general follow the regulatory guidance outlined in International Conference on Harmonisation of Technical Requirements for Registration of Pharmaceuticals for Human Use (ICH) document S5(R2). However, because many biopharmaceuticals are species-specific, alternate approaches may be needed to evaluate DART potential as outlined in ICH S6. For molecules that show species-specific cross-reactivity restricted to non-human primates (NHP), some aspects of DART may require NHP testing. For biopharmaceuticals that are uniquely specific and only active on intended human targets or human and chimpanzee targets, surrogate molecules that cross-react with the more traditional rodent species may need to be developed and used for DART testing. Alternatively, genetically modified transgenic animals may also need to be considered. Surrogate molecules and transgenic animals may also be considered for DART testing even if the biopharmaceutical is active in NHPs in order to reduce the use of NHPs. Because of the unique properties of biopharmaceuticals, a case-by-case approach is needed for DART and general toxicity evaluation, which requires consideration of specific product attributes including biochemical and biophysical characteristics, pharmacological activity, and intended clinical indication. Birth Defects Res (Part B), 33:176–203, 2009. © 2009 Wiley-Liss, Inc. 相似文献