US7 and Its Uses

Agricultural scientists are searching for ways to prevent fruit from spoiling while in storage. They report they are making progress. Several kinds of diseases affect fruit while in storage. Each kind is caused by a different microorganism. Each is costly to fruit farmers and producers of fruit products. Throughout the world, about 25 percent of all harvested fruit spoils while in storage. It is not safe to eat. For years chemicals have been used to protect stored fruit. However, these chemicals do not always work. They threaten the health of humans, and they harm the environment. That is why agricultural scientists began searching for other ways to control storage diseases. Their efforts finally have produced some results.

Scientists have discovered that some yeasts and bacteria act as natural bio-control agents. The yeasts and bacteria protect against the microorganisms that destroy stored fruit. Charles Wilson is an American government plant scientist in the state of West Virginia. He works with a scientist from Israel, Adoo Chalotz. Recently the two men discovered a very helpful kind of yeast. The yeast protects against three different fruit diseases and the three kinds of fungi that cause green mould, blue mould and sour rot. They named the yeast US7. It can be used to protect peaches, grapes and tomatoes. It even protects stored wheat.

The two scientists discovered the yeast while washing some lemons before putting them in storage. They discovered that the clean lemons could not be stored as long as the lemons that had not been washed.

A private company now is developing a way to produce large amounts of US7. It also is testing different ways to put the yeast on fruit. One possibility is a powder to shake on fruit. Another is a liquid to spray on fruit. The yeast can be used before or after the fruit is harvested.

In the past few years, United States government has banned many old chemical methods of protecting fruit from storage disease. Robert Spotts, a plant scientist at Oregon State University, says new methods are needed urgently. US7 is just one of several bio-control methods that should help meet this need.