Pear Mold E Fair Projects

Pear science fair projects explore moldy environments...

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

RESEARCH REPORT

Introduction
Pears are an important part of our economy. Pears are also a great tasting food. Without a tasty treat life wouldn’t be fun.  Although there are many ways that pears can go bad, the two most common are Blue and gray Mold. There are many ways to treat pears to resist mold.

Pears
Pears are a very interesting fruit. They are a very fleshy fruit. Pears come in many different shapes, and sizes, they can have the most common shape, where the stem is pointed, and the bottom is much more rounded.  They also can look just like an apple, and can be as small as a cherry.  There are hundreds of different types of pears. Many of them have a core like an apple, containing, on average, about 10 seeds. A pear tree can be as tall as 45 feet, and 25 feet wide, at the base. Pear trees can live a very long time, sometimes up to 75 years. The most common pears are Bartlett, Comice, Anjou, Bosk, Hardy, Seckel, and Winter Nelis. It is not known when pears were first found, but there are hints. One poet wrote about the fruit in the 700’s B.C. Washington State is the number one producer of pears per year (14,830,000 bushels) in North America. 

Blue Mold
Blue mold is also known as Pennicilium. It is not a nesting mold (does not spread from fruit to fruit), unless the pears are in a water system, and one has a wound. Blue mold is first formed through the stem. Blue mold can grow on pears much longer after harvest than, on apples. This is because the pears stem remains moist, while the apples, dries up. Blue mold accounts for 24% of damaged harvest.

Gray Mold
Grey mold is also known as Botrytis Cinerea. Unlike blue mold, gray mold is a nesting fungus. As with blue mold, Botrytis Cinerea can be transferred by a water system. Gray mold is likely to occur in low temperatures. Grey mold accounts for 55% of damaged harvest. 

Mucor Rot
Mucor Rot is also known as Mucor Piriformis. Mucor rot usually begins in the soil of the areas where the fruit grows. If the soil is extremely moist, and there are many decaying things on the ground mucor rot is very possible. Mucor rot can also develop in winter.  It can also be spread to bins that have been laid on the ground.  The rot can be absorbed by the bin, and contaminate all pears in the bin.  Mucor rot is accountable for 8% of damaged crop every year. 

Bulls-Eye Rot
Bulls-eye rot is also known as Pezicula Malicorticis. This is a slow growing fungus. Bulls-eye rot is not usually discovered until storage. Although it usually starts when the pears are tiny.  Bulls-eye rot is indicated by the concentric rings, found inside the contaminated fruit.

Coprinus Rot
Coprinus rot is also known as Coprinus Psychromorbidus. It is commonly mistaken for bulls-eye rot. Even though coprinus rot is similar to gray mold, in the fact that it is a nesting mold. This rot comes from mushroom spores, found from a mushroom in the orchard.  It usually infects the fruit one month before harvest. Although it is commonly mistaken for bulls-eye rot the main difference is that coprinus rot looks like a cobweb like fungal growth on the surface of the fruit. 

Chlorine
Chlorine can be a very effective way to treat for mold and rot. It is a contact killer. It is commonly used in fruit dump tanks.  Although the concentration of the chlorine must be correct for it to be effective (if the spores are away from the main concentration then many fruit will still be infected). Chlorine minimizes the amount of dirt in the tank, which reduces the chance of infection. Chlorine does not, however cover the pears in the long run, such as from storage to the market.

Oil
Oil is a commonly used method of treating fruit for mold prevention.  Although usually oil itself is not the only thing on the fruit. Usually it is a special wrap that is impregnated with oil that remains on the fruit.  Oil is a contact killer, so if there is any mold on the pear then it should eliminate it. Making it complicated for other molds to grow on it.

Zinc Oxide
Zinc oxide is not a commonly used treatment for the prevention of postharvest mold, and decay. A common type of zinc oxide is Nutraphos-24.

Summary
In conclusion, mold and rot are very damaging things to the Washington economy, and agricultural economics around the world. With all the various types of mold and rot it is very complicated, if not impossible, to solve them all. Although thanks to many studies there are ways to stop the leading damages of harvest, and many other types of damages. 

ACKNOWLEDGEMENTS

I would like to thank the following people for helping make my project possible:
* My parents for driving me to the various places were I needed to be
* Mr. Newkirk for helping me with many aspect of my project
* Doug Anyan for allowing me to use his research lab to conduct my experiment
* Tom Eisley, John Baranowski, Dr. Gamlem, and Joel Hollingsworth for granting my SRC approval. Abstract