FUNGUS CONSIDERED AS A TOOL TO KILL COCA IN COLOMBIA

Under pressure from the United States, Colombia has reluctantly agreed to
take the first step toward developing a powerful biological herbicide
against the coca and heroin-poppy fields that are spreading almost
unchecked across its countryside, Colombian and United States officials
said yesterday.

For years, United States officials have been quietly debating ways to
conduct field tests of such an herbicide, developed from a fungus that
occurs naturally in many types of coca and other plants.

Now, Colombian officials say they are completing a proposal to the United
Nations that would include testing for the presence of the fungus, Fusarium
oxysporum, in coca, the raw material of cocaine.

If the fungus is found in Colombian varieties of coca, Colombian scientists
would go on to evaluate its effectiveness, safety and environmental impact
before deciding whether to produce the herbicide.

"What we want is a program of research -- and only research -- on the use
of biological controls against these crops," the Colombian environment
minister, Juan Mayr, said in an interview yesterday.

The Colombian government is uneasily supporting the project as President
Clinton is about to sign a bill providing $1.3 billion in aid to Colombia
to fight drug traffickers and the insurgents who protect their trade.

Some powerful Republican in Congress told Colombian officials that they
were supporting the spending on the expectation that that Colombia would
agree to explore the use of Fusarium fungus in its coca fields.

Within the Clinton administration, officials said, the testing of fungal
herbicides was also pushed by the White House drug policy adviser, Gen.
Barry R. McCaffrey, and by officials of the United States Southern Command,
which is overseeing the American overhaul of Colombia's armed forces.

Environmentalists and other activists in both countries are raising a din
of objections to any field tests of the fungus, arguing that it is
virtually a biological weapon -- one that might upset Colombia's ecology or
endanger farmers, animals and food crops.

Last year, similar complaints by environmentalists in Florida prompted
state officials there to put aside plans to test a variant of Fusarium for
possible use against marijuana fields.

Several plant pathologists who have studied the fungus extensively said
there was relatively little scientific basis for the assertions about its
danger. They acknowledged that a great deal of testing still needed to be
done, but they added that the most significant unanswered questions might
have less to do with the safety of the fungus than with its effectiveness
and cost.

"If they're looking at local strains of the fungus, then I can't see
something scientifically dangerous about it," said Jonathan Gressel, a
professor of plant sciences at the Weizmann Institute of Science in
Rehovot, Israel. "What you're doing is taking a disease that is already
present and putting on more of it."

"But they'll be lucky if it works," Dr. Gressel added. "Because typically
this inundative strategy isn't good enough in commercial agriculture, and
I'm sure the narcos have been planning ahead. They'll probably go to
fungicides or breed their coca to be resistant to the fungus. It's
relatively easy to do."

The concerns about Fusarium's proposed use as a mycoherbicide, or fungal
herbicide, have been heightened by the shadowy history of research into its
impact on drug crops. Indeed, the Colombian study is being proposed after
many years of often secret investigation by scientists in the United States
and the former Soviet Union.

Officials said Fusarium, a naturally occurring fungus with variants that
can cause wilt in everything from tomatoes and grain to marijuana, was
first identified as a possible weapon in the drug fight by Central
Intelligence Agency scientists in the early 1980's. The United States
Agriculture Department began more extensive research into the use of the
fungus on coca in 1988, and it continued, mostly in secret, for nearly a
decade.

At roughly the same time, Soviet biological weapons scientists at the
Institute of Plant Genetics in Uzbekistan were working to develop Fusarium
fungus, plant bacteria and other pathogens to destroy opium poppies -- and
perhaps enable Moscow to limit the world's morphine supply or undermine the
opium-dependent economy of Afghanistan.

After the collapse of the Soviet Union, the United States continued to pay
for research at the laboratory as part of an effort to keep its
impoverished scientists from joining the biological weapons programs of
countries like Iraq and Iran.

Some of the same research now continues under the auspices of the United
Nations Drug Control Program, with has quietly supported the use of
biological controls against drug crops since 1976. In Uzbekistan, as in
Colombia, much of the United Nations effort is financed by the United
States.

"Whatever happened in the past, the work has to be redone now in an open
environment," said Eric Rosenquist, one of the officials who has worked
longest on the fungus. "Only then can you debate it on its merits."

"I don't see this as some horrible thing that's going to mutate and kill
people -- that's science fiction," added Mr. Rosenquist, a program leader
for international programs at the Agriculture Department's Research Service
in Beltsville, Md. "But you have to demonstrate that it is going to be
effective, and that hasn't been done yet."

Mr. Rosenquist and other officials noted that a natural epidemic of
Fusarium in Peru, beginning in the mid-1980's, had only a limited effect
on the cultivation of coca there.

The attraction of the fungus as an herbicide is that its strains have
generally been found to attack only a single type of plant, entering the
roots and strangling the vascular system while leaving other species
untouched. The fungus can live on in the soil for many years, moving from
one coca plant to another.

Proponents of fungal herbicides say they may prove to be much less damaging
to the environment than chemical herbicides that are now typically used to
fumigate drug fields.

Similar biological controls are increasingly being used to kill weeds,
noted David C. Sands, a plant pathologist who has led much of the research
on Fusarium's potential use against coca. "The question is whether this is
considered a noxious plant," he said.

Dr. Sands, a plant pathologist at Montana State University, worked almost
singlehandedly to revive congressional interest in mycoherbicides after the
Agriculture Department began to phase out its support for Fusarium research
in 1996.

He also holds a patent on what officials say would be the likely method for
dispersing the fungus if it is ever used on coca or opium poppies. The
design involves dropping Fusarium-coated seeds from planes flying over coca
fields, at higher altitudes than the crop-dusting planes and helicopter
that are routinely attacked by drug producers and guerrillas.

For some years, lawyers at the White House and the State Department
debated whether it was possible to use the fungal herbicide on drug crops
without violating the international conventions against the spread of
biological weapons. The lawyers determined that the law would not be
violated if a foreign country made its own decision to use or test the
fungus, but that has not satisfied all American officials.

"I don't support using a product on a bunch of Colombian peasants that you
wouldn't use against a bunch of rednecks growing marijuana in Kentucky,"
said one United States intelligence official. "And there is definitely less
than unanimous support for this in Colombia."

Mr. Mayr, the Colombian environment minister, said he had flatly rejected
the first proposal for a mycoherbicide research plan that was sent to him
in late April by the United Nations Drug Control Program. A summary of the
plan stipulated that "the government of Colombia has agreed, in principle,
to experimental field trials being conducted in that country."

Mr. Mayr and two other senior Colombian officials said they will propose
instead to test only fungal herbicides that already exist in Colombia. "If
Fusarium is not there, we won't study it," he said. But they agreed to
look at various types of biological controls against coca, including
predatory insects.

The United Nations drug control director in Bogota, Klaus Nyholm, and the
assistant secretary of state for international narcotics and law
enforcement affairs, R. Rand Beers, suggested that they would support the
new Colombian plan.

"This is an idea that ought to be investigated," Mr. Beers said of the
fungus's potential as a herbicide. "It should not be implemented until the
science is clear. But if it is, then it should be considered a tool."