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- <text id=91TT2623>
- <title>
- Nov. 25, 1991: Invasion of the Superbug
- </title>
- <history>
- TIME--The Weekly Newsmagazine--1991
- Nov. 25, 1991 10 Ways to Cure The Health Care Mess
- </history>
- <article>
- <source>Time Magazine</source>
- <hdr>
- ENVIRONMENT, Page 84
- Invasion of the Superbug
- </hdr><body>
- <p>A voracious insect is chewing its way through California crops,
- and consumers across the U.S. may pay the price
- </p>
- <p>By Michael D. Lemonick--Reported by Jeanne McDowell/Los Angeles
- </p>
- <p> By this time of year, fields in the Imperial Valley, which
- straddles the California-Mexico border, should be bursting with
- ripe melons ready for shipment to markets around the U.S.
- Instead, 95% of the fall crop has been lost and much of the rest
- lies rotting on the vine. Harvests of lettuce, broccoli,
- cauliflower, squash, citrus fruits, table grapes, sugar beets,
- carrots and cabbages are threatened as well. Total crop losses
- in Imperial County and nearby Riverside County have already
- reached $90 million. Says melon grower Ben Abatti, who has been
- farming in the area since 1956: "It is total disaster."
- </p>
- <p> The agent of disaster is a 3-mm (one-tenth-in.) insect
- known to scientists as the poinsettia strain of the sweet-potato
- whitefly but to farmers as the Superbug. Millions of these
- voracious insects have spread over the Imperial Valley, massing
- on the undersides of leaves and sucking plants dry, weakening
- or killing them in the process. Farmers first noticed the flies
- getting worse in July, and by September swarms of them looked
- like white clouds. They covered windshields and got stuck
- between people's teeth. Farm workers had trouble inhaling and
- eventually had to wear masks. Not since the Mediterranean
- fruit-fly scares of the early and late 1980s has California's
- $18 billion agriculture industry, which during winter supplies
- close to 90% of the fresh produce in the continental U.S., been
- so alarmed by a pest.
- </p>
- <p> The first hint of a visit by fruit flies is invariably met
- with quarantines and airborne-insecticide spraying campaigns.
- The new Superbug has no effective native predators in
- California, and pesticides are largely useless against it. If
- it continues unchecked, Imperial Valley could be put out of
- business for months. That could cause an estimated $200 million
- in farm losses by spring and higher prices at the produce
- counter. The wholesale price of melon has tripled, and by one
- reckoning, the average cost of a head of lettuce in a
- supermarket could go from $1.19 to about $1.50. In some areas,
- these foods may be in short supply.
- </p>
- <p> California farmers have been fighting other types of
- sweet-potato whiteflies for years. But the poinsettia strain,
- so named because it first appeared in the U.S. on poinsettia
- plants in Florida greenhouses, reproduces twice as fast as its
- relatives and consumes five times as much food from its victims.
- It comes originally from somewhere halfway around the world,
- possibly Iraq or Pakistan, and apparently reached America in
- 1986, probably hidden away in a cargo shipment.
- </p>
- <p> Florida is a little too cool and rainy, on average, for
- the Superbug's taste, and the infestation there was never as
- serious. But when the fly arrived in Southern California,
- probably in a fruit basket or vegetable shipment, it felt right
- at home in the dry weather and summer temperatures that can
- reach 46 degrees C (115 degrees F). Because the insect is happy
- eating some 500 varieties of plants (one of the only vegetables
- it doesn't seem to like is asparagus), it found the fertile
- Imperial Valley to be a veritable smorgasbord.
- </p>
- <p> Since all pesticides approved for use in California have
- been ineffective against the bug, the best advice agriculture
- officials can give is for farmers to plow under devastated
- fields, denying the pests their food sources. In addition,
- roadways and ditches around the valley are being cleared of
- weeds that help sustain the whitefly. Farmers are considering
- a "host-free" period in which they will do no planting at all.
- Says John Pierre Menvielle, who farms 900 hectares (2,200 acres)
- in Calexico: "If that is what it takes, we will do it."
- </p>
- <p> One possible long-term solution, says Nick Toscano, an
- entomologist at the University of California at Riverside, is
- a tiny stingless wasp that lives in the California desert. It
- lays eggs on the immature whitefly, and when they hatch, the
- baby wasps eat the fly. Other researchers are cross-breeding the
- poinsettia whitefly with more innocuous varieties in hopes of
- developing a mild-mannered hybrid that might displace the
- Superbug. In the next six or nine months, a team of scientists
- will leave for the Middle East in search of a parasite from the
- fly's native habitat that could combat it. A promising natural
- pesticide is neem-seed extract from the Indian Azadirachta
- indica tree. The bugbusters may have to resort to synthetic
- insecticides that are not approved in California but may have
- to be--in a hurry.
- </p>
- <p> Unfortunately, that last option could end up causing more
- trouble in the long run. The toughness of the poinsettia
- whitefly has evolved over generations. "It has been exposed to
- pesticides for a long period of time and developed resistance,"
- explains Toscano. Using new pesticides could halt the bug's
- advance for now--but given its ability to adapt, the result
- could be some sort of Ultimate Bug that would make Superbug look
- tame.
- </p>
-
- </body></article>
- </text>
-
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