3. Background
• What is unknown:
• What makes the microbe beneficial
• What determines if a microbe is a symbiont or a
phytopathogen
• Trends between these beneficial microbes from
different plants
5. Background
• Only 33% of bacterial species detected in the
molecular analysis were present for the culture
dependent analysis (Matsuzawa, H., et al., 2010).
• Bacterial species may live interchangeably as a
symbiotic endophyte or phytopathogen
• Fungal antagonist Fusarium oxysporum in lettuce
(Moretti et al., 2012).
6. Background
• After inoculating a beneficial microbe it was shown
to increase pathogen resistance in Pinus sylvestris,
potato and tomato varieties (Ardanov et al., 2012).
• Microbes reduce the need for fertilizers and
pesticides (Horrigan et al., 2002).
7. Goal of the Study
• Find common genetic precursors
• Determine how these microbes slip past the plant’s
innate immune system
• See if microbes from different plants can be used to
increase growth of other plants
8. My part
• Sequencing endophytes from seaweed
• Inoculate microbes on Arabadopsis thaliana and
duckweed
• Sequence entire genome of bacteria that display
beneficial growth
9. • Isolated endophytes from seaweed and seawater in
Brazil
• Grown on LB with glycerol and stored in -80°C
• 16S Colony PCR
• Sanger sequencing
Methods
22. Future Work
• Inoculate cultures on Arabadopsis and duckweed
• Sequence ones that have an effect on the plant
• Expand study to other locations and plants
• Questions?
Editor's Notes
Hello, today I am going to be talking about my version of the plant microbiome project. I know a few of the members of the lab are doing this, and jenny spoke about this last week.
Monsanto video on microbes and how they help the world
Definitions
Rhizosphere microbiome – beneficial for plant growth and health. Organisms found in the rhizosphere include bacteria, fungi, oomycetes, nematodes, protozoa, algae, viruses, archaea and arthropods. Most of the organisms in the rhizosphere biome belong to a complex food web that utilizes the large amount of nutrients released by the plant.
Genetic sequencing showed that there are common genetic systems that allow these bacteria to colonize in a plant.
The problem is that many of these bacteria require the plant host to survive, so they are not detected in culture dependent studies. This is why the 16s rRNA analysis is good. It is very sensitive and will amplify these microbes. This is a culture dependent analysis though since they were grown on LB.
We would like to see if there is something about their DNA that shows they will be beneficial or harmful to the plant
(is it that theyre undetectible or can the plant discriminate the beneficial microbes from pathogenic)
We will take these microbes and grow them on arabadopsis and on duckweed to see if they have benefits to these land plants even though seaweed is from the sea.
Seaweed name= ulva lactuca
He isolated the endophytes the same way as duckweed except he had to cut the seaweed up first since its large. Then bleached in about 15% bleach and rinsed with rinse solution and then distilled water 3 times. Then the plants were plated on LB and grown up and transferred to glycerol stocks
9 bacteria colonies as endophytes and 6 from the water of grumari beach
4ednophyte bacterial colonies from trindade beach
4 endophyte colonies and 12 bacterial colonies from the water here.
Conserved in almost all bact-variable enough to distinguish to certain level
Shows phlyum and genus of bacteria but loses power to more specific you get.
The black parts are the conserved regions and the squiggles are the variable regions that allow us to distinguish between them. We are using the DNA that makes the RNA to study it.
These are supposed to be around 925 bp. The controls in both sets have contamination and in the second picture there are no bands in the bacteria but there are in the controls.
