Transcript Turfgrass and Genetics

Turfgrass and Genetics
Because plants have diseases, too!
By Jessica Kaczmarek
Why are turfgrasses important?
• Used in:
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Lawns of buildings
Roadsides
Athletic fields
Golf courses
• Benefits
– Reduce soil erosion
– Trap dust and
pollutants
– Moderate temperature
– Beautify the
environment
$$ Multibillion dollar business annually! $$
Creeping Bentgrass Gets Sick
Meet…the DOLLAR SPOT and BROWN PATCH!
Two fungal pathogens!
What can be done?
Alternative I
• Fungicide
• Pathogen strains
become resistant
• Negative impact on
human health
Alternative II
• Transgenic plants
• More sustainable
resistance to pathogens
• Safer for human health
Atlantic White Shrimp, Litopenaeus
setiferus
Antimicrobial peptide Penaeidin4-1
(Pen4-1)
ANTIMICROBIAL PEPTIDES (AMP’S)
Short sequence peptides with
fewer than 50 amino acid
residues, most of which have
antimicrobial activity against
many pathogens.
Expression of a Novel Antimicrobial
Peptide Penaeidin4-1 in Creeping
Bentgrass (Agrostis stolonifera L.)
Enhances Plant Fungal Disease Resistance
Dr. Chen, et al., at Clemson University
Published September 12, 2011
Promising Conclusions
Expressing Pen4-1 in Creeping
Bentgrass DEFENDS Against Fungal
Pathogens.
DNA Construct
Pen 4-1 Nucleotide Sequence from Shrimp
Altered for Plant-Optimized Codon Usage
How to Make Transgenic Plants
Technique: Agrobacterium-mediated Transformation
1. Cut grass leaves in small pieces (1cmx1cm).
2. Soak in Agrobacterium fluid for 10 minutes.
3. Cells along cut will be transformed by Agrobacterium.
DNA insertion occurs.
4. Under right conditions, plants will regrow.
Wait, wouldn’t transformation
disrupt the genes or regulatory
sequences at the transgene
integration site?
Highly unlikely. Transgenic plants
show similar phenotypes and have
increased resistance to pathogens.
In vitro plant leaf inoculation assay:
R. solani (brown patch)
In vivo plant inoculation bioassay:
R. solani
Second wave of inoculation:
R. solani
In vitro plant leaf inoculation assay:
S. homoeocarpa (dollar spot)
In vivo plant inoculation:
S. homeocarpa
Future
Stable transmission of Pen4-1 into
next generations using the original
transgenic plants (large-scale
application)
Ask A Question Time
What makes Pen4-1 a good
candidate for genetic
engineering of enhanced disease
resistance in plants?
Inhibits many plant pathogenic
fungal species, including multi-drug
resistant species
How did the experimenters know
the DNA construct was taken up
during the Agrobacteriummediated transformation?
Extract genomic DNA and conduct PCR
amplification; increased pathogen
resistance is evident
Are transgenic plants different
from normal plants?
No significant differences in general
plant morphology, root and shoot
development was observed
References
1.
2.
“Expression of a Novel Antimicrobial Peptide Penaeidin4-1 in
Creeping Bentgrass (Agrostic stolonifera L.) Enhances Plant Fungal
Disease Resistance.” Man Zhou, Qian Hu, Zhigang Li, Dayong Li, ChinFu Chen, Hong Luo. Published September 12. 2011.
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