My present research investigates the possibility of developing
alternative methods (electronic nose, near infrared spectroscopy
NIRs) for the identification of microorganisms and the plant
disease diagnosis. Moreover, the organic volatile compounds (VOCs)
production during the plant-microbe interaction has also been
considered for their possible effect in the plant-pathogen
interactions.
Among the organic volatile compounds, special attention was paid
to ethylene and jasmonic acid derivatives for their influence on
plant resistance mechanisms.
From 2009-2010, my research is also focused in elucidating the
pathogenic interactions occurring between kiwifruit species (A.
deliciosa and A. chinensis) and the bacterium Pseudomonas syringae
pv actinidiae.
The research aims to develop a method allowing to monitor in
vivo the plant-bacteria interactions during the infection process.
This non-destructive method will allow the direct visualization of
the spatio-temporal interactions of P. syringae pv actnidia (PSA)
in intact Actinidia chinensis and A. deliciosa tissues. To
reach this objective, a stable and broad host- range plasmid
vector, pDSK-GFPuv, which expresses GFPuv (driven by a constitutive
chloroplast promoter, psbA) at high levels has been inserted in
competent PSA cells.
The GFPuv-labeled plant pathogenic bacteria not only can be
easily visualized at the cellular level under a fluorescence
microscope but also are clearly visible, as bacterial colonies, to
the naked eye at the whole-plant level under longwavelength UV
light. The plant-pathogen interactions are studied be means of
fluorescent steromicroscope and by confocal laser scanning
microscopy.
In addition, a reliable protocol for inoculation which is
able to mimic the natural infection and it is, at the same time,
repeatable has been tested. The inoculation method allows to obtain
symptomatic plants in a relatively short with symptoms similar to
the ones observed in field.
Development of novel e-nose based diagnostic system
Summary: the research deals with the development of
alternative methods (electronic nose, near infrared spectroscopy
NIRs) for the diagnosis of plant disease and the identification of
plant-associated microorganisms. The most recent researches
investigate also the possible biological role of VOCs and the
airborne plant-to-pant or plant-microbe interactions.
Possible Thesis Duration: 6 months
Expertises/competences achieved during the research
thesis:electronic nose use and data-processing, basic
bacteriology, micropropagation, VOCs analysis and identification
ability, nucleic acid extraction as well as PCR detection of
bacterial species.
External collaborations:
Prof. S. Cristescu - Radboud University, Life Science
Trace Gas Facility, Heyendaalseweg 135, 6525 AJ, Nijmegen, The
Netherlands
Dr. J.L. Vanneste – Plant and Food, Ruakura Research Centre,
East Street Private Bag 3123, Hamilton, New Zealand
Develop of new methods for the real-time monitoring of
Pseuomona syringae pv. actinidiae directly in
plant.
Summary: The research aims to develop a method allowing
to monitor in vivo the plant-bacteria interactions during the
infection process. These non-destructive methods will allow the
direct visualization of the spatio-temporal interactions of P.
syringae pv actnidia (PSA) in intact Actinidia chinensis and A.
deliciosa tissues.
To reach this objective, a stable and broad host- range plasmid
vector, pDSK-GFPuv, which expresses GFPuv (driven by a constitutive
chloroplast promoter, psbA) at high levels will be inserted in
competent PSA cells.
The GFPuv-labeled plant pathogenic bacteria not only can be
easily visualized at the cellular level under a fluorescence
microscope but also are clearly visible, as bacterial colonies, to
the naked eye at the whole-plant level under longwavelength UV
light.
The plant-pathogen interaction will be successively studied be
means of fluorescent steromicroscope and by confocal laser scanning
microscopy.
Once the protocols have been optimized for this pathosystem,
they will allow to clarify crucial aspects of the infection process
such as:
-
how the bacteria invade the plant tissues
-
how far the bacteria spread inside the plant tissues
-
how the plant defenses can contain the bacteria spread
The knowledge of this aspects will help in developing the most
appropriate cultural strategies to contain the disease and to
evaluate the most effective treatments to reduce the infection
incidence and severity.
Finally, these methods may also be applied for Determination of
temperature thresholds for PSA infection.
Possible Thesis Duration: according with the specific
subject at least 3 days per week for 6 months.
Expertises/competences achieved during the research
thesis:nucleic acid extraction, bacterial transformation,
microscopy techniques, diagnostic methods
External collaborations: University of Siena, Department
of BioPhysics-Univeresity of Bologna, Plant&Food Research (New
Zealand).
