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Trudy Wassenaar

has published a book about - what else? - bacteria, describing them in all their microscopic grandeur.  In case you enjoy your visit of this virtual museum, you might also like to read this  book - in real life (as a printed book) or in the virtual world: the book is available for eReader, too.

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Bacteria and plants

Bacteria live near, on, and in plants just like they do with other higher organisms. Plants can benefit from the presence of bacteria or they can suffer from bacterial diseases. Let's start with a mutually benign relationship: plants that are dependent on bacteria for growth, and in return provide the bacteria with food. That is how alfalfa lives happily together with Rhizobium meliloti. The hosting requires communication, and how bacteria and plants talk together is subject of present-day research. Another field of research is applying biotechnology to produce bacteria that are beneficial to plants, for instance in the combat of diseases.

  • Bacteria are at the beginning and end of the food cycle. They produce organic matter from CO2 just like plants do, and serve as food for larger organisms. At the other end of the food chain they compost organic material into CO2. Read this interesting article about ecology in a nutshell.  Learn more about bacteria's role in the nitrogen cycle. 

Bacteria can use the plants just as a support to grow on. You can't normally see them, but if you would make a blue print of a plant leaf on an agar plate that supports growth, the result is a bacterial print of a leaf. Here is a do-it-yourself-instruction to isolate bacteria from soil. Did you know that bacteria help plants to grow?  

Indirect damage to plants can occur when bacteria promote the formation of ice crystals on soft fruit, like strawberries. After scientists discovered that secreted bacterial proteins formed the core of such crystals, they disabled the gene encoding this protein. These were among the first genetically modified bacteria used to protect crops . Here's what the WHO writes about genetically modified foods. Read about the possibilities of biotechnology and plants. 

Bacteria can also cause diseases in plants. It is one of the subjects of Plant Pathology.

Plants are not defenseless against infections, they have an 'immune system' too. Disease-resistant plants can recognize pathogenic bacteria, and our understanding of this process may one day result in healthier crops . As everywhere in Nature, it is an arms race. Although the plants protect themselves, bacteria are efficient intruders, and have evolved specific mechanisms to deliver proteins or even DNA into plants. Scientists make use of this: bacteria as a tool to transform plants. How bacteria use the plant's defence for genetic modification.  

Next time you take a stroll outside, enjoy the sight of a flower or buy your veggies, think of all those bacteria that either did good or tried to do harm to those plants that surround us. Bacteria are everywhere!


Book recommendation

Wassenaar BacteriaBacteria: The Benign, the Bad, and the Beautiful

Dr. Trudy Wassenaar

Publisher's info


Missing Microbes: how the overuse of antibiotics is fueling our modern plagues - by Dr. Martin J. BlaserMissing Microbes: how the overuse of antibiotics is fueling our modern plagues

Dr. Martin J. Blaser

Publisher's info


Press release: An unusual job, by T.M. WassenaarPress release: An unusual job

Dr. Trudy Wassenaar

Publisher's info

Latest News

responsive webseitenThe Virtual Museum of Bacteria is now available on smartphone, tablet, iPhone and iPad.



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Mycobacterium lepraeDr. T. M. Wassenaar

View the organism:

Mycobacterium leprae under the microscope (D. Kunkel).


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