Transgenic crop technology left the "wow" stage in 1997. And in 1998 it entered the all-out competitive war stage among the chemical-company giants that brought us the technology.

Little wonder. Hundreds of millions of dollars per year - and billions longer term - are at stake.

Monsanto's Roundup Ready soybean system created perhaps the biggest product introduction excitement in chemical and seed industry history - certainly in recent history. Some scientists called it "Roundup Ready mania."

It sent chills down the collective spines of competitors - and launched a marketing war on a scale likely never seen before.

It's too early to assess what will happen if the announced merger of the two biggest rival companies, Monsanto and American Cyanamid, becomes final.

So far, the big winners are farmers.

Two of the major players, DuPont and AgrEvo, cut prices on their competitive herbicides. DuPont's price cuts varied by herbicide, but, on balance, they were deep.

AgrEvo, with its Liberty Link system for corn and also for soybeans in '99, lowered the price of Liberty herbicide some, too. The company also added 44 more weeds "controlled" to its label, bringing the total to 101 grass and broadleaf weeds.

Seed companies that put those herbicide-resistant genes into the crops involved - and that's almost all of them - are locked in a competitive battle as well.

More than 100 seed companies, for example, now offer Roundup Ready soybeans, and a similar number offer the Liberty Link corn technology. This year, Roundup Ready corn was introduced by one company, Dekalb. And Liberty Link soybeans were supposed to hit the market, but the launch was postponed because the expected clearances didn't come from the European Union.

Last year was the second year farmers had Roundup Ready soybeans, except those who participated in Experimental Use Permit testing. Most growers were very happy with the weed control results. Many, if not the majority, were happy with yield results.

But "disappointing" was the word many growers used to describe some varieties they tried. Some university agronomists maintain that yield potential has a ways to go on many varieties.

Probably no scientists and only a small percentage of growers smarting from subpar yield results blame the technology per se. The blame is on some seed companies that rushed the breeding process to cash in on the new technology, which farmers eagerly awaited.

Scientists, and even most growers who sacrificed some yield, feel that the yield problem will be overcome within two or three years.

Meanwhile, STS soybeans have continued to turn in grade-A performances, with good weed control, no crop injury and excellent yields. They were still gaining acres before STS herbicide prices were cut, and those price cuts were expected to hike acreage in '98.

Poast Protected corn continues to gain converts and acreage. One big reason is that it gives farmers a good tool to hammer stubborn weeds that have come on strong in recent years. That's because those weeds aren't controlled by some otherwise excellent, widely used herbicides.

IMI-resistant corn, the first herbicide-resistant crop out the chute, faltered a bit after its introduction but then grew at a moderate pace. The introduction of Lightning herbicide by American Cyanamid gave IMI corn a new demand boost.

Last year, Garst Seeds also came out with a gene-stacked corn hybrid resistant to both IMI and Liberty herbicides. Garst also has a hybrid that combines genetic resistance to Lightning and Liberty herbicides, as well as Bt protection against European corn borer.

Overall, most experts predict the transgenic or biotech crop revolution will continue to build momentum. And although it toughens the challenge for plant breeders, stacking genes to include several beneficial traits in one variety or hybrid is the wave of the future, say most scientists.

One cloud has hung over the revolution. That's the acceptance of transgenic crops in Europe. The 15 countries that make up the European Union have proved to be a formidable challenge. But the light at the end of the tunnel has brightened a little with recent positive developments.

For details on all of these herbicide-tolerant crop developments, read the individual stories in this Special Report.