Under an awning set up at a tiny outpost guarded by U.S. Marines, the district governor of Nawa is pleading with three dozen solemn-looking farmers and village elders not to plant the crop that feeds the world heroin market.

Haji Abdul Manaf, a farmer and onetime leader in the fight against Russian occupiers, has several parts to his passionate anti-poppy pitch.

Moral: Planting an illegal crop puts you in collusion with criminals and violates the Koran. Practical: If Nawa continues to be known as the center of the poppy crop, outsiders like the Americans won’t come here to build schools, clinics and roads.

And then the direct approach.

“If you grow poppy, we will catch you, destroy your crop and put you in jail!” shouted Manaf, as his audience stared impassively, some fingering worry beads, others nibbling on plates of garbanzo beans, raisins and tiny candies.

It is a speech that Manaf, at the behest of the Americans, makes frequently at open-air meetings of farmers and elders: sometimes in a shady spot in different marketplaces, sometimes at the Nawa district government center, once at the unfinished mansion of a now-jailed drug kingpin.

The district governor’s appearances are part of a counter-narcotics strategy that has changed dramatically since the Bush administration but remains crucial to the war effort, particularly in Helmand province, the heart of the poppy-growing region.

The poppy crop provides the money that allows the Taliban to carry on its insurgency against the government in Kabul and its American and NATO allies. The U.S. and United Nations estimate that drug traffickers pay insurgents as much as $500 million a year to grow and protect the crop and then smuggle it into processing labs in Afghanistan and elsewhere.

At the presentation in Nawa, Manaf was at a Marine compound ringed by barriers, barbed wire and gun towers. Manaf was accompanied by Lt. Col. William McCollough, whose troops descended on Nawa in July with the primary mission of protecting the civilian population from Taliban brutality and a secondary mission of putting a dent in the region’s poppy crop.

With the fast approach of the planting season for spring harvest, however, that secondary mission has taken on renewed urgency.

The Obama administration believes previous counter-narcotics efforts that focused on destroying crops drove many farmers and influential tribesmen into supporting the Islamist insurgency. So the U.S. and British governments have taken a hands-off approach to an eradication program in which Afghan soldiers burn or plow under fields of poppy before the crop can be harvested. Instead, special forces troops from both nations -- as well as dozens of U.S. Drug Enforcement Administration agents deployed over the summer -- are active in finding and interdicting the routes used to smuggle poppy resin from Afghanistan to processing plants thought to be in Iran and Pakistan.

The Afghan government also is trying to persuade farmers to stop growing poppy and shift to other crops, particularly wheat. The U.S. and British governments are underwriting a program to give farmers high-grade wheat seed and fertilizer at a reduced price, enough for several plantings. The Afghan government has agreed to buy at least a portion of the crop. An estimated 4,800 farmers will receive the seed and fertilizer out of an estimated 80,000 to 100,000 people in the Nawa district. The number of recipients was determined by government officials in Kabul, the capital.

A similar program was tried last year, but distribution was done solely at the provincial capital, Lashkar Gah, and the effort was undercut by corruption and thievery, officials said.

Still, poppy production plummeted -- by one report, more than 20% nationwide -- although one reason might have been the skyrocketing price for wheat. Some observers also have suggested that the Taliban ordered a cutback to drive up the price of heroin.

When the Marines rode into Nawa in July, Taliban fighters, after two weeks of attacks, fled to a nearby community called Marja. U.S. and Afghan National Army forces are planning an assault on Marja akin to the U.S. assault on Fallouja, Iraq, in 2004. The action could take place as a reported 9,000 additional Marines deploy to Helmand province, a move expected in the wake of President Obama’s new war strategy announcement Tuesday.

U.S. officials believe that Marja has also become a center for drug-marketeers who seduce or coerce the farmers of Helmand province into growing poppy. Removing the Taliban from Marja would remove the narco-racketeers, leaving the farmers with no one to buy their poppy crop, officials say.

The message for farmers is blunt: Shift to wheat (or corn or grapes or another crop) because soon poppy will no longer be profitable. “By April, Marja will no longer exist,” McCollough said.

Success in Marja would be a step forward, but the fight against the poppy crop here has only just begun -- and it promises to be formidable.

When Manaf talked about poppy, his audience, sitting cross-legged on the ground, said little. But when he threw open the gathering to other topics, the reaction was swift and heated.

The farmers complained about lack of water, and elders talked bitterly about the U.S. detaining their sons and tribesmen as suspected members of the Taliban.

“I don’t know why these things are happening,” said one farmer, staring angrily at McCollough. “We are getting tired of the Marines -- they are making problems for us.”

Before the farmers left, the Marines distributed Korans, prayer rugs and small radios. A U.S.-run station plays pro-government, anti-Taliban, anti-poppy messages, along with music and some news.

But the Taliban is not giving up Nawa without a fight. Marines continue to find roadside bombs and detain villagers for possessing bomb materials. Three community leaders friendly to the Americans were killed over a two-week period, one of them just hours after attending Manaf’s speech. He was a former Taliban who had switched sides.

To prevent a repeat of last year’s problems with the wheat seed distribution, the program is being run through the government center, adjacent to the Marine compound, which is called Cherokee. Afghan employees are in charge, but armed Marines are nearby, in “over watch.” The seed bags are stamped as coming from the Islamic Republic of Afghanistan. No mention is made of the U.S. or Britain.

Driving aging tractors and small trucks, the farmers arrive to complete the paperwork and receive the sacks of seed and fertilizer. The cost is about $17, a tenth of the value of the seed. The fertilizer is low-grade and not likely to be used in making bombs, officials said.

“These are not bad people,” said Ian Purves, a Briton assigned to work with the farmers of Nawa. “They’re not growing poppy to screw up the U.S. or U.K. or to fund the Taliban. They just want to feed their families.”

Yet persuading farmers not to plant poppy is not an easy sell. “We’re realistic, we know poppy will be grown in Helmand, just not as much,” McCollough said.

As well as supporting farmers, poppy is a labor-intensive crop that provides jobs during harvest for villagers, even college students and government workers. Also, wheat is a thirsty crop -- in an area where water distribution is chaotic.

On the other hand, addiction is growing among the youth of Helmand province. A third or more are rejected as applicants for Afghan national security force jobs because of addiction. One farmer chained his son to the house in hopes of breaking his addiction.

After the Marines pushed the Taliban from Nawa, a “civilian surge” of officials from the State Department, the U.S. Agency for International Development and the British government arrived. The officials are encouraging the Afghan education system to initiate an anti-drug program in schools.

“You try to push them in a different direction,” said Mack McDonald, State Department senior governance specialist in Nawa. “But ultimately the people here have to stand up and say ‘enough is enough.’ ”

tony.perry@latimes.com