Silicon deprivation enhances localized autofluorescent responses and phenylalanine ammonia-lyase activity in oat attacked byBlumeria graminis

Carver, T. L. W.; Robbins, Mark P.; Thomas, B. J.; Troth, K; Raistrick, N.; Zeyen, R. J.

doi:10.1006/pmpp.1998.0149

Cited by 54 publications

(32 citation statements)

References 35 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…Oat plants deprivated of Si increased the activity of phenylalanine ammonia lyase and, consequently, the accumulation of phenolic compounds in epidermal cells colonized by Blumeria graminis f.sp. avenae (Carver et al, 1998). Furthermore, in the context of Pythium ultimum infection, the activities of chitinases, peroxidases and polyphenoloxidases were much higher on the roots of cucumber plants supplied with Si than on roots of plants that were not supplied with this element (Chérif et al, 1994).…”

Section: Introductionmentioning

confidence: 94%

Photosynthetic gas exchange and antioxidative system in common bean plants infected by Colletotrichum lindemuthianum and supplied with silicon

Polanco

Rodrigues

Nascimento

et al. 2014

Trop. plant pathol.

View full text Add to dashboard Cite

This study investigated the effects of silicon (Si) on the resistance of common bean plants to anthracnose caused by Colletotrichum lindemuthianum. The plants were grown in a nutrient solution containing 0 (control) or 2 mM Si (+Si) and both photosynthesis and antioxidative metabolism levels were evaluated. The Si concentrations in the leaf tissues of +Si plants increased by 33% in comparison to those of control plants. Anthracnose severity was reduced by 34% in +Si plants in comparison to control plants. The net carbon assimilation rate, stomatal conductance to water vapor and transpiration rate values were significantly higher in +Si plants than in control plants. The activities of superoxide dismutase (SOD), ascorbate peroxidase (APX) and glutathione reductase (GR) tended to be higher in +Si plants than in control plants. The hydrogen peroxide concentration was significantly lower in +Si plants than in control plants. In conclusion, the Si supply was associated with lower anthracnose severity and up-regulation of antioxidant enzymes, which in turn might be associated with better gas exchange in +Si plants. The impaired photosynthetic performance in +Si plants was associated with stomatal limitations, whereas in control plants those impairments likely reflected dysfunctions at the level of biochemical reactions involved in CO 2 fixation.

show abstract

Section: Introductionmentioning

confidence: 94%

Photosynthetic gas exchange and antioxidative system in common bean plants infected by Colletotrichum lindemuthianum and supplied with silicon

Polanco

Rodrigues

Nascimento

et al. 2014

Trop. plant pathol.

View full text Add to dashboard Cite

show abstract

“…After oxidative ashing of all organic materials with sulphuric acid, silica deposits extending far beyond the papilla proper were isolated from 22 non-related plant species, naturally infected by their specific powdery mildews (Blaich and Grundhö fer, 1998). In silica-deprived oat plants, infected by powdery mildew, the degree of silica deposition greatly decreased but the deposition of autofluorescent polyphenolics and the associated increase of phenylalanine ammonia lyase activity were enhanced (Carver et al, 1998b). These results indicate that the cells are rather flexible in compensating for the lack of orthosilicic acid by an increased use of polyphenolics for the formation of papillae.…”

Section: Introductionmentioning

confidence: 94%

Silica deposition by a strongly cationic proline‐rich protein from systemically resistant cucumber plants

et al. 2003

View full text Add to dashboard Cite

SummaryInfection of one leaf of cucumber (Cucumis sativa) plants can render other leaves resistant to various pathogens. This so-called systemic acquired resistance (SAR) can be functionally mimicked by certain chemicals. All these treatments enhanced expression of a gene encoding a novel proline-rich protein (PRP1) which has C-terminal repetitive sequences containing an unusually high amount of lysine and arginine residues. Antibodies raised against a synthetic peptide derived from four of the repetitive sequences cross-reacted mainly with a cell wall polypeptide of an apparent MW of 8 kDa. The protein accumulated upon SAR induction, though it does not appear to take part in oxidative protein cross-linking, at least in the hypocotyl tissue. The synthetic peptide derived from the repetitive sequences was able to polymerize orthosilicic acid to insoluble silica, a property not resulting directly from the primary protein sequence, but rather from the high positive charge density. Our results suggest that during induction of SAR, the synthesis of a strongly cationic PRP prepares the cell walls for enhanced silica deposition which is known to participate in cell wall reinforcement, localized at the site of attempted penetration of fungi into epidermal cells. Constitutive accumulation of related PRPs may function in silica deposition during certain developmental stages, a process important for various physiological functions of green plants.

show abstract

“…The cell wall is the primary interface for pathogen interactions and therefore is an important site of potential defense mechanisms, such as cell wall deposition and strengthening (Cano-Delgado et al, 2003). Autofluorescent phenolic compounds are mainly implicated in cell wall strengthening; an autofluorescence assay, therefore, allows a general view of potential defense mechanisms (Carver et al, 1998;Torregrosa et al, 2004). Stronger autofluorescence was detected in F83005.5 cortical cell walls and could be linked with the reduced bacterial penetration in the root.…”

Section: Root Symptom Development In Response To Infection Is Geneticmentioning

confidence: 99%

Dissection of Bacterial Wilt on Medicago truncatula Revealed Two Type III Secretion System Effectors Acting on Root Infection Process and Disease Development

et al. 2009

View full text Add to dashboard Cite

Ralstonia solanacearum is the causal agent of the devastating bacterial wilt disease, which colonizes susceptible Medicago truncatula via the intact root tip. Infection involves four steps: appearance of root tip symptoms, root tip cortical cell invasion, vessel colonization, and foliar wilting. We examined this pathosystem by in vitro inoculation of intact roots of susceptible or resistant M. truncatula with the pathogenic strain GMI1000. The infection process was type III secretion system dependent and required two type III effectors, Gala7 and AvrA, which were shown to be involved at different stages of infection. Both effectors were involved in development of root tip symptoms, and Gala7 was the main determinant for bacterial invasion of cortical cells. Vessel invasion depended on the host genetic background and was never observed in the resistant line. The invasion of the root tip vasculature in the susceptible line caused foliar wilting. The avrA mutant showed reduced aggressiveness in all steps of the infection process, suggesting a global role in R. solanacearum pathogenicity. The roles of these two effectors in subsequent stages were studied using an assay that bypassed the penetration step; with this assay, the avrA mutant showed no effect compared with the GMI1000 strain, indicating that AvrA is important in early stages of infection. However, later disease symptoms were reduced in the gala7 mutant, indicating a key role in later stages of infection.

show abstract

Silicon deprivation enhances localized autofluorescent responses and phenylalanine ammonia-lyase activity in oat attacked byBlumeria graminis

Cited by 54 publications

References 35 publications

Photosynthetic gas exchange and antioxidative system in common bean plants infected by Colletotrichum lindemuthianum and supplied with silicon

Photosynthetic gas exchange and antioxidative system in common bean plants infected by Colletotrichum lindemuthianum and supplied with silicon

Silica deposition by a strongly cationic proline‐rich protein from systemically resistant cucumber plants

Dissection of Bacterial Wilt on Medicago truncatula Revealed Two Type III Secretion System Effectors Acting on Root Infection Process and Disease Development

Contact Info

Product

Resources

About