Plant Fertilizers::: *Urgent*

[judy4000]

My science fair project is about plant fertilizers and to find which of the main elements in fertilizers are the most important.
I was planning to buy fertilizers so that each had one had different main elements that contained the most.."confusing"
For example if i was trying to test if nitrogen was the most important element, then buy a fertilizer that contained more nitrogen
than the other two elements, phosphorus and potassium.
I figured i needed a little development in my idea/experiment.
Please mention some suggestions or any mistakes or anything else to comment on
thank you!!!!

[aelin]

Hi,

That sounds like a very important question in the field of agriculture. Wikipedia has a quite good page on fertilizers, so I'd suggest starting there (http://en.wikipedia.org/wiki/Fertilizer). I'm not a fertilizer expert, but from my understanding, the main elements of fertilizer are ALL essential, meaning that they are all necessary for the plant to grow. If a single one of those elements is missing or below necessary levels, the plant will most likely die.

What you could consider would be the effects of each type of deficiency on the plant. For example, a plant with a magnesium deficiency might start forming yellow stripes among its leaves, whereas a plant with a different type of deficiency might show another effect. You could take a guess at what causes the odd effect and do some sort of functional study to check if the effect results from a particular function being shut down (in the previous example, the yellow stripes might be from shutdown of photosynthesis function, and there are ways to test this).

Hope this helps!
Aaron Lin

[deleted-71828]

Hi,

I think you can develop this idea into a testable hypothesis.

Check out this Science Buddies resource on Nitrogen Fertilizers:

https://www.sciencebuddies.org/science- ... p012.shtml

Here is the main page:

https://www.sciencebuddies.org/science- ... a=PlantBio

Also check out this pdf I found:

http://ppi-far.org/ppiweb/bcropint.nsf/ ... 7-1p08.pdf

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With that being said, here is what I suggest. You must do background research. Not only will this open your eyes to what research has already been done, you will
learn more and you will come up with additional questions you will want to answer in your experiment. Develop a hypothesis once you have done all background research.

I am not sure if fertilizers sold will show the amounts of elements in each type but it will be advantageous to find this out. Then you can determine if there is perhaps an adequate ratio of all nutrients and elements. Also do not forget about controls, positive and negative. For instance, I can see you doing research and determine the most important elements in fertilizer and doing a supplement study (say, + x amount of element compared to a negative control which was not supplemented).

But I cannot stress enough to get your mind clicking early by researching and looking for resources. It will allow you to read more scientific articles and will help you develop that scientific framework.

Take Care!

[judy4000]

Thank you so much for the replies!!
I still have some other questions: I was thinking about some constants
How do you measure pH of soil using the computer equipment (vernier probes)?
How do you make the germination time a constant?

Also, how do you know/measure how much "sunlight" the plant consumes?

[deleted-71828]

Hi,

Here are some links to help you measure pH of soil:

http://serc.carleton.edu/microbelife/re ... pH_EC.html

http://www.wikihow.com/Test-Soil-pH

http://hubcap.clemson.edu/~blpprt/acidity2_review.html

http://www.eutechinst.com/techtips/tech-tips6.htm

http://soil.gsfc.nasa.gov/pvg/ph.htm

In regards to germination time, you can normalize the germination time. Here are some papers
that mentioned normalization.

http://www.jstor.org/stable/4045136

http://books.google.com/books?id=AHVDtv ... me&f=false

(If the actual times to germination at different ti/ (Fig. 5a) are multiplied by this factor, the time courses can be normalized to a common time course)


http://wssajournals.org/doi/abs/10.1614/WS-08-122.1

http://www.jstor.org/stable/4045136

Hope that helps!

Phong