papaya as fungicide

d_dakay · Post by **d_dakay** » Sun Jan 08, 2006 6:44 pm

good day! thank you for answering my que last day.
now again im asking for your help again.
i want to know more about papaya seed extracts as fungicide.
pls help me.

thanks in advance!

dianne

hiramuzammal · Post by **hiramuzammal** » Sun Jan 08, 2006 7:49 pm

Here are the links to some articles that might help:

http://www.actahort.org/books/628/628_98.htm

http://iliahi.com/kavaresearch_pdf/kava ... gicide.pdf

Again, you can base your procedure on the methods used by the previous studies.

donnahardy2 · Post by **donnahardy2** » Mon Jan 09, 2006 7:35 am

Hi Dianne,

Do you need help designing an experiment for your project? Please let us know what you are thinking about doing if you have questions.

From my observations, I think papayas are a good growth medium for fungi. Hawaiian papayas, especially, in the grocery stores always seem to have fungi growing on them. I don't like to eat food with mold, so I have had to discard a few expensive papayas. I have 3 papayas at home right now, and I'm hoping they will ripen so I can eat them before they grow mold. Are you interested in developing a new method for inhibiting fungal growth on papaya, or do you want to test the ability of papaya to inhibited mold growth?

Donna Hardy

d_dakay · Post by **d_dakay** » Mon Jan 09, 2006 9:43 pm

hello! thank you again!
ah... i want to test the ability of papaya to inhibit the growth of fungi. my test organisms are Botrytis squamosa and Botrytis cineria in Onions and Tomatoes.
i am welcome for your suggestions ma'am.

thanks in advance

dianne

donnahardy2 · Post by **donnahardy2** » Tue Jan 10, 2006 9:34 am

Hi Dianne,

This sounds like it will be an excellent project. Here are some things you should consider:

1. Do you have access to a microbiology laboratory? This experiment really should be done in a regular laboratory. Have you every grown fungi in a laboratory before?

2. Do you have a method for testing for fungal inhibition? There are two standard methods and the following article describes a new method that you could use if you had access to the equipment. With the radial growth method, the test fungicide (in this case, papaya seed extract) is added to the cooled potato dextrose agar just before the agar plates are poured. The test organism is inoculated onto the center of the plate and the growth of the fungal colony is measured in centimeters after 3 days of incubation. In the dry weight method, the Botrytis is grown in a liquid culture medium for 3 days and the fungus is then filtered and dried before it is weighed. The third new method requires a microplate reader and preparation of a standard suspension of fungal spores. You can choose just one method for your experiment.

http://www.apsnet.org/pd/pdfs/2003/0317-04R.pdf

3. Do you have cultures of the two test organisms? How will you maintain the stock cultures? One very important point that is mentioned in the reference above is that the culture used to test for fungicide activity must be actively growing when it is transferred to the test medium. The automated method uses spores.

4. For your experiment, you should use more than one concentration of papaya seed extract. I would recommend using between 3 and 7 different concentrations. You should also run the samples in duplicate or triplicate. If at all possible, run the experiment more than one time. What is your independent variable in this experiment? What is the dependent variable? What will you use for controls?

I hope these suggestions will help. Please let us know if you have any questions.

Donna Hardy

d_dakay · Post by **d_dakay** » Sat Jan 14, 2006 10:51 pm

hello again!
thank for your suggestions.
i am really interested on that study but unfortunately, in our place we do not have a good laboratory to conduct this study. me and my coleagues also doesn't have enough money.
do have any other sci proj. to give me?
i'll welcome any project you will give me..

Dianne

donnahardy2 · Post by **donnahardy2** » Sun Jan 15, 2006 8:12 am

Hi Dianne,

I'm disappointed that you aren't going to be able to do this project. Perhaps you can make arrangements to do it for next year, because it really is a good idea. It might take a couple of trials to adapt one of the test methods to your resources, and with more time, you could do a really good job on it.

If you want to stay with papayas, perhaps you could do a survey to find out how to buy a papaya that won't mold before it gets ripe enough to eat. I would love to have the answer to this question. You could purchase papayas from different sources and monitor the time it takes for the papaya to get ripe, and if necessary, identify the mold growing on the papaya. You would need a microscope to identify the mold, a ruler to measure mold growth, and a camera. I can give you additional suggestions if you are interested in this project. What would the independent and dependent variables be for this project? What would your hypothesis be?

When is your project due? What else are you interested in? Let me know if there is anything in your sciences classes that you have been particularly interested in, or if you have noticed something that you'd like to have an answer to. I will think of some more topics for you.

Donna Hardy