Question about necessary concentration of urea for radish growth

[Millacol88]

I have a project in my grade 11 biology class to design a controlled experiment showing how some factor affects plant growth, specifically radishes. I have decided to add urea as a nitrogen fertilizer to one group and do nothing to the other leaving all other factors the same between the two groups.

I have found this pdf: http://www.fspublishers.org/ijab/past-issues/IJABVOL_6_NO_3/19.pdf
This experimentation shows a significant increase in plant height, root length, and number of leaves when the plants were enriched with urea. The concentrations of urea are given.

My experiment, however, will be on a much smaller scale. I am growing 24 plants, each in its own individual compartment, around 4cm long by 4cm wide by 5cm deep. I need to know if I can use the same concentration of urea as was used in the study I linked to.

 

[bobze]

I have a project in my grade 11 biology class to design a controlled experiment showing how some factor affects plant growth, specifically radishes. I have decided to add urea as a nitrogen fertilizer to one group and do nothing to the other leaving all other factors the same between the two groups.

I have found this pdf: http://www.fspublishers.org/ijab/past-issues/IJABVOL_6_NO_3/19.pdf
This experimentation shows a significant increase in plant height, root length, and number of leaves when the plants were enriched with urea. The concentrations of urea are given.

My experiment, however, will be on a much smaller scale. I am growing 24 plants, each in its own individual compartment, around 4cm long by 4cm wide by 5cm deep. I need to know if I can use the same concentration of urea as was used in the study I linked to.

It might be better to vary your concentrations with say 5 or 6 plants in each experimental concentration group. For instance try it with their concentration, double their concentration and half their concentration (and a control group with none).

 

[Millacol88]

I'm sorry, I should have clarified that I only have 24 radish plants to grow in total. That's including the test group and the control. I could try a twelve-plant control and a twelve plant test group, with that test group split up into three different levels of concentration. I'm still not sure what those concentrations should be.

 

[Millacol88]

Sorry to bump a thread, but I killed one of my test groups with too much urea, and I'm struggling to find any information about what specifically too much of a nitrogenous compound does to plants. Could anybody point me to a source that has anything on this?