Science Buddies: "Ask an Expert"

Thinking about using h202 on vegetables and flowers. I will be using a trichoderma strain for roots. I understand that if I use the h202 as a drench will kill the good bacteria. If used as a spray for the leaves and branches will that go to the roots and kill the trichoderma strain. What would be a good mixture of 3 percent h202 per gallon of water

Hi,

3% H2O2 will kill many types of bacteria but not all. If you want to sterilize the roots I think you will have to expose them directly to the peroxide. Spraying the leaves is not going to work. H2O2 breaks down releasing a single oxygen atom very quickly and it is this highly reactive oxygen that kills the bacteria. The single O does not last very long, so H2O2 is most effective when it is in contact with the surface to be sterilized (http://www.quickgrow.com/gardening_arti ... lture.html).

Peroxide can be harmful to all kinds of cells, not just bacteria, so be sure to use only 3%. I don't know if watering with H2O2 alone will kill bacteria on the roots. You may have to remove the plant from its pot, soak the roots in peroxide and then replant it. Scientifically, you would have to prove that all bacteria were gone from the roots but this seems like it would be rather difficult.

Does this answer your question? What is your project about? Are you planning to inoculate plants with trichoderma fungi to make them resistant to drought or to improve growth?

Sybee