Blue and Gray Mold E Fair Projects

Name: Colin
Grade Level 7th
Awards: Mid-Columbia Science Fair. Distinction for thouroghness. third place. Washington State Science and Engineering Fair,second place.

PURPOSE

The purpose of this experiment was to determine the best way to reduce blue mold (Penicillium), and gray mold (Botrytis cinerea) on red D’Anjou pears, in open air.

I became interested in this idea when I talked to Doug Anyan, and he told me of a similar experiment that he had done at his work.

The information gained from this experiment would benefit most fruit growers, especially pear growers, by reducing their reliance on fungicides.

HYPOTHESIS

My first hypothesis was that vegetable oil would be the most effective treatment to stop mold on post harvest, red D’Anjou, pears.

I based my hypothesis on the many experiments done with oil wraps that I have read about, and the fact that they have all been very effective.
 

My second hypothesis was that the chlorine solution would be the worst treatment to stop mold on red D’Anjou pears.

I based my hypothesis on the thought that the chlorine solution would run off the pear, and provide little protection after that. I also read that when chlorine is used it may not be effective enough. 

EXPERIMENT DESIGN

The constants in this study were: 
* The type of pear being used (red D’Anjou)
* The temperature at which the pears will be set out (21 degrees Celsius)
* The place were the products where tested
* The procedures for measuring the mold growth
* The amount of trials per Treatment
* The way of inoculating the pears

The manipulated variable was the type of product used to stop blue and gray mold.

The responding variable was how much blue or gray mold developed on the pear.

To measure the responding variable I made a visual scale (1-10. One being little or no mold, and 10 being mold encrusted), and rated each pear.  I then averaged the ratings.

MATERIALS

PROCEDURES

1. Put on gloves, goggles, and mask.
2. Pour 32 ounces of water into the mixing container (the 50oz container).
3. Add 8.8 ounces of chlorine (500 parts per million).
4. Take one pear and (using your dominant hand) dip the pear in the solution for 7 seconds.
5. Repeat step 4 (make sure to pick up the next pear with the hand that has not been in the solution, so all the pears do not have that solution), for 9 more pears.
6. Pour out the container, and wash it out with tap water.
7. Wash gloves.
8. Pour 32oz of water into the mixing container.
9. Repeat steps 4-5.
10. Repeat step 6
11. Repeat step 7
12. Repeat step 2
13. Take 4oz of zinc oxide powder, and pour it into the container.
14. Stir the solution.
15. Repeat steps 4-5
16. Repeat step 6-7
17. Take a paper towel, and saturate it with the vegetable oil.
18. Take one pear and wipe the towel over it (making sure to get the stem and bowl).
19. Repeat step 18 for the remaining pears.
20. Take a disposable pipette and put the tip of it into the mold, and puncture the fruit.
21. Take a screwdriver and enlarge the wound, made by the pipette.
22. Repeat steps 19, and 20 for three pears in each of the groups. 
23. Clean gloves, and throw them away (so no bad stuff is in the garbage) 
24. Clean the screwdriver, and dispose of the pipettes.
25. Let the pears sit for 14 days.
26. After the 14 days take all the pears and, using the visual guide and safety procedures (in step 1), grade each pear.
27. Repeat steps 2 and 3 and soak one pear group, and dispose of them.
28. Repeat step 27 for the remaining pear groups. 

RESULTS

The original purpose of this experiment was to determine what treatment would prevent mold from growing on a red D’Anjou pear.

The results of the experiment were that oil was the best treatment to prevent mold growth on red D’Anjou pears. The results of this experiment also indicate that zinc oxide was the worst treatment to prevent mold growth on red D’Anjou pears 

See the table and graph below

CONCLUSION

My first hypothesis was that the oil treatment would be the best at preventing mold. My second hypothesis was that the chlorine would be the worst at preventing mold.

The results indicate that my first hypothesis should be accepted because the oil treatment had an average of .15. The results of this experiment also indicate that my second hypothesis should be rejected, because zinc oxide was the worst treatment to prevent mold. 

Because of the results of this experiment, I wonder what would happen if I where to use a different pear, instead of the Red D’Anjou.

If I were to conduct this project again I would test a different type of pear, and see if the same results occurred. I would also use a fungicide, and see how well it compares to the other treatments. Abstract