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A food revolution beckons, but few show up; other news

(Friday, Aug. 19, 2005 -- CropChoice news) --

1. A food revolution beckons, but few show up
2. GM plants use carbon nanofibres
3. Bill on DNA-altered crops reaps organic outrage
4. Can gene-altered rice rescue the Farm Belt?
5. GMO debate comes to Lake County
6. Scientists warn of GM superweed risk

1. A food revolution beckons, but few show up

By Peter N. Spotts, Staff writer
The Christian Science Monitor, 15 August 2005
http://www.csmonitor.com/2005/0815/p01s03-ussc.html

It's the kind of breakthrough scientists often dream about.

They have unraveled the complete genetic blueprint for rice - the staple for more than half of the world's population. The development - a key to future genetic blueprints for other cereals and grains - should make it far easier to engineer better, more nutritious crops that could trigger a second "green revolution," whose predecessor - using more traditional farming and breeding approaches - is said to be running out of gas.

There's just one problem. It's not clear the world is ready for another food revolution if it involves splicing foreign genes into crops.

"The initial expectation that this technology would be rapidly adopted turned out to be a bit optimistic," says Michael Rodemeyer, executive director of the Pew Initiative on Food and Biotechnology. "We're in a stall in the development of new GM foods."

To be sure, farmers are producing more bioengineered crops every year. Farmers have found many of these genetically modified crops quite useful. GM soybeans are cheaper to grow; GM papaya has saved Hawaiian growers from a virus that had made their traditional crop unmarketable. But these remain first-generation GM varieties with only indirect consumer benefits.

The next generation - offering consumers better-tasting, more nutritious, or longer-lasting food - is taking longer than the industry's optimists expected, Mr. Rodemeyer adds.

The reasons are legion, analysts say.

Outside the United States, public reluctance and activist campaigns citing everything from environmental concerns to the extensive clout of multinational corporations have slowed the introduction of GM crops. This resistance led Monsanto last year to shelve the first commercially available genetically engineered wheat. US wheat growers worried that GM-wary global customers would buy elsewhere.

Within the US, where farmers plant more than 167 million acres of GM crops, public unease has been less evident. But some analysts expect that to change as companies genetically engineer crops to make them more nutritious or harness crops to produce compounds for drugs.

Second-generation GM crops also pose a tougher scientific challenge than the first-generation did. The traits researchers want to enhance are likely to involve several genes and complex interactions between the plant and its environment.

In this political and scientific environment, rice is poised to become the latest "crop celebre" in the ongoing debate over conventional and genetic-engineering approaches to feeding the world.

The new rice genome, pulled together by researchers worldwide under the umbrella of the International Rice Genome Sequencing Project, was completed three years ahead of schedule. Researchers say much of the credit for the speed goes to Monsanto for making available the rice data it had. Scientists picked rice as the first cereal crop to sequence because of its genome's relative simplicity. Other, more complex cereals share rice's genes, often in the same positions in long DNA assemblies known as chromosomes. Thus, rice has the potential to become a Rosetta stone for reading other key cereal genomes.

"That's one of the exciting aspects" about having the rice genome in hand, says Sally Leong, a research chemist with the US Department of Agriculture's Agricultural Research Service lab in Madison, Wis. And the international nature of the project has helped build capabilities within some key developing countries.

Now comes the tricky part, scientifically associating the genes or gene combinations with specific plant traits and processes. As that information becomes available, traditional breeders can use it to identify useful genes and then trace their movement through several generations. By using seedlings alone, researchers speed up traditional breeding. Rice genetically engineered by inserting foreign genes, however, may face a tougher challenge.

Several charitable foundations and international research institutes are working to enhance the level of "micro- nutrients" - trace minerals such as zinc and iron - as well as vitamin A in rice. The enhanced rice could help in the fight against malnutrition.

Yet golden rice so far has languished, partly because of environmental concerns. Some of the countries that could most benefit have imposed regulatory barriers that are too costly for the public project, says Jorge Mayer, golden-rice project manager at the University of Freiburg, Germany.

In the US, meanwhile, a California biotech company proposing to grow GM rice on a 200-acre plot in Missouri was sent packing in April. The rice had been modified to produce two synthetic human proteins for pharmaceuticals. Anheuser-Busch, worried about contamination of conventional rice, threatened to boycott all Missouri-grown rice used in its brewing activities if the project was approved.

"In the quest to ease global malnutrition, too much emphasis is being placed on genetic engineering without a sufficient look at the risks and alternatives", says Doreen Stabinsky, a geneticist by training who serves as a science adviser to Greenpeace. "We need a realistic assessment of what the technology can and can't do."

2. GM plants use carbon nanofibres

Azonano.com, August 15, 2005
http://www.azonano.com

Researchers are developing new techniques that use nanoparticles for smuggling foreign DNA into cells.

For example, at Oak Ridge National Laboratory, the US Department of Energy lab that played a major role in the production of enriched uranium for the Manhattan Project, researchers have hit upon a nano-technique for injecting DNA into millions of cells at once. Millions of carbon nanofibres are grown sticking out of a silicon chip with strands of synthetic DNA attached to the nanofibres. Living cells are then thrown against and pierced by the fibres, injecting the DNA into the cells in the process.

Its like throwing a bunch of baseballs against a bed of nails...We literally throw the cells onto the fibers, and then smash the cells into the chip to further poke the fibers into the cell. - Timothy McKnight, engineer, Oak Ridge Laboratory.

Once injected, the synthetic DNA expresses new proteins and new traits. Oak Ridge has entered into collaboration with the Institute of Paper Science and Technology in a project aimed to use this technique for genetic manipulation of loblolly pine, the primary source of pulpwood for the paper industry in the USA.

Unlike existing genetic engineering methods, the technique developed by Oak Ridge scientists does not pass modified traits on to further generations because, in theory, the DNA remains attached to the carbon nanofibre, unable to integrate into the plants own genome. The implication is that it would be possible to reprogram cells for one time only. According to Oak Ridge scientists, this relieves concerns about gene flow associated with genetically modified plants, where genes are transferred between unrelated organisms or are removed or rearranged within a species.

If the new technique enables researchers to selectively switch on or off a key trait such as fertility, will seed corporations use the tiny terminators to prevent farmers from saving and re-using harvested seed - compelling them to return to the commercial seed market every year to obtain the activated genetic trait they need?

This approach also raises a number of safety questions: what if the nanofibres were ingested by wildlife or humans as food? What are the ecological impacts if the nanofibres enter the cells of other organisms and cause them to express new proteins? Where will the nanofibres go when the plant decomposes in the soil?

Carbon nanofibres have been compared to asbestos fibres because they have similar shapes. Initial toxicity studies on some carbon nanofibres have demonstrated inflammation of cells. A study by NASA found inflammation in the lungs to be more severe than in cases of silicosis, though Nobel laureate Richard Smalley, Chairman of Carbon Nanotechnologies Inc. gives little weight to these concerns: We are confident there will prove out to be no health hazards but this [toxicology] work continues.

http://www.checkbiotech.org/root/index.cfm?fuseaction=news&doc_id=11001&start= 1&control=207&page_start=1&page_nr=101&pg=1

3. Bill on DNA-altered crops reaps organic outrage

By KRISTIN COLLINS, Staff Writer
The News & Observer, Aug. 13, 2005

The idea of rearranging the DNA of plants once sounded like the stuff of science fiction.

Today, man-made plants that repel pests or survive heavy doses of weedkiller cover 3 million acres of North Carolina farmland -- and state agriculture leaders are paving the way for more.

A bill likely will pass in the legislature this session that will stop local governments from banning genetically modified crops, as three California counties have done. The bill, requested by the Department of Agriculture, passed in the Senate on Friday, the last major hurdle to its success. The House, which passed the bill in May, must agree to a few changes to make it final.

No North Carolina county or city has tried to ban the crops. But the bill has created a maelstrom among those who say that genetically engineered crops pose a danger to the food supply and could destroy organic farming. "They're really playing with Mother Nature in a pretty perverse way," said Ken Dawson, an organic vegetable farmer from Orange County. "We don't know what the consequences are."

The outrage is heightened by a new genetically modified crop in North Carolina that, unlike most others, is intended to go directly into the food supply.

This year in Washington County, a California company planted 75 acres of rice implanted with a human gene that produces proteins found in human milk, saliva and tears. The company plans to extract the proteins and use them in food products that they say could help infants in the Third World.

Those who oppose the crops say they can easily cross-pollinate with organic and conventional crops, destroying rare heirloom varieties and making natural food almost extinct.

Now, as the bill awaits final passage, state leaders are in the middle of a rowdy debate over the future of high-tech agriculture.

"Research and science has moved agriculture from the horse and plow and very low yields to very efficient operations that can meet the world's food demands," said state Agriculture Commissioner Steve Troxler, who grows genetically modified soybeans on his Guilford County farm. "I don't know that we can afford to stop doing that."

Genetically modified crops are the products of biotechnology companies, which have figured out how to add genes to plants' DNA to make them resistant to pests or to the weedkiller Roundup.

Farmers, who pay the companies for the rights to use the patented seeds, say the mutant crops make farming easier and more efficient and cut down on the use of pesticides and herbicides. Ninety-five percent of cotton, 87 percent of soybeans and 52 percent of corn grown in North Carolina this year are genetically modified, according to the Department of Agriculture. Right now, most genetically modified crops do not go directly into the food supply. Most of the soybeans and corn are used for livestock feed, not sold in grocery stores. But their uses are expanding.

Troxler is among many state agriculture leaders who say that genetically modified crops provide the best hope for keeping farmers in business in difficult times -- and for feeding the world on less and less land. Troxler said the Agriculture Department asked for the bill, which is similar to those being floated in several other states. It would give the state Board of Agriculture, which Troxler chairs, sole authority to outlaw plants.

He said the push comes at the request of seed dealers, farmers and agribusiness companies that were concerned about what they saw in California and New England -- where "genetically engineered free" movements have gained steam.

"The public is very misinformed," said Wade Byrd, a Bladen County corn farmer. "We're going to use fewer pesticides and have a safer food product when we get more of these crops on the market."

In California, several counties have held referendums on whether to ban the plants locally. Three have been successful. In Vermont, more than 80 local governments have passed resolutions barring them. And in Maine, one town has passed a resolution, and others are considering similar action.

In North Carolina, where no such movement has gained a foothold, state officials said they thought the bill would pass without fanfare. It slid through the House in May with only one dissenting vote.

But advocates of organic farming got wind of it soon after, and it didn't have such a smooth road in the Senate. On Thursday, a Senate committee amended the bill to create a study commission that will examine the risks and benefits of genetically engineered crops. It also added two new members to the state Board of Agriculture: an organic farmer and a consumer advocate.

Tony Kleese, head of the Carolina Farm Stewardship Association, which promotes organic farming, said the new bill is better -- but still not palatable.

He said it will all but assure that genetically engineered crops can spread unchecked.

He said allowing local governments to create zones where genetically engineered crops aren't allowed could protect organic crops from being contaminated by wind-blown pollen. Now, that right will be taken away, regardless what the study shows.

Kleese and other organic advocates say genetically engineered crops haven't been studied enough to prove they're safe. Europeans shun them, banning any U.S. product that contains them.

They call the bill the work of giant biotech companies -- such as Monsanto, a Missouri company that owns the rights to most of the genetically modified seeds used on American farms -- that want to protect their profit margins.

"Do we want these companies to own our food supply from seed to plate?"

Kleese said. "The more of these kinds of laws that go into effect, the more the balance tips to genetically engineered crops. We need to ask a lot of hard questions before we continue down this path."

Sen. Charlie Albertson, a Duplin County Democrat, was one of the bill's sponsors.

He said it's unrealistic to think that organic farmers, who sell vegetables and fruits at a premium, can feed the masses. He said the expansion of genetically engineered crops will ensure an abundant and affordable food supply.

"The truth is, organic crops are out of the reach of most people who are buying produce," Albertson said. "We can't grow them at the expense of genetically modified crops. These crops offer the best hope in the world to feed hungry people."

4. Can Gene-Altered Rice Rescue the Farm Belt?

By ALEXEI BARRIONUEVO
NY Times, 08/16/05

WATSON, Mo. - Like an expectant father, Jason Garst stood in calf-deep water and studied the three-foot-high rice plants growing in a flooded field here.

It was a curious sight in northwest Missouri, where the growing season is considered to be too short for rice. Mr. Garst, a sixth-generation farmer, is hoping at least one of the 12 varieties on his test plot will sprout this fall. If one does, he will start growing rice plants that have been genetically engineered to produce proteins found in human milk, saliva and tears. Once converted into a powder form, those proteins would be used in granola bars and drinks to help infants in developing countries avoid death from diarrhea.

"I know in my heart that this will be better than anything else we are doing," said Mr. Garst, 35, who also farms soybeans and potatoes.

The rice project is backed by a private company called Ventria Bioscience but also has the support of the state and a local university, which are hoping to reverse the long decline in the area's farm economy. But the project has run into opposition from environmental groups and even the beer giant Anheuser-Busch amid fears about the health effects of genetically engineered crops, making Mr. Garst's little rice paddy a piece of a larger battlefield.

The economic and academic ambitions of the Missouri project make it unique, but the arguments echo those heard in similar disputes in Europe and, increasingly, in the United States. Critics of Ventria's plans are concerned that the gene-altered rice could contaminate regular rice crops and pose a health risk to consumers, scaring off buyers. Ventria and its academic partner in the project, Northwest Missouri State University, say they can control the potential for contamination. And they say the risks are minimal when balanced against the potential for the special rice to help cut the costs of drugs and save lives.

The debate has a certain urgency in the Farm Belt because it highlights the challenge facing much of the region's economy: finding new products that will reduce farmers' reliance on commodity crops. As equipment has become more efficient and foreign competition has stiffened, farms have consolidated and profit margins have shrunk, forcing farmers to plant ever more acres to squeeze out a living. The genetic engineering work that Ventria and other companies are doing can add value to products like rice, offering farmers a more stable income that does not rely on steep government subsidies.

"There is no question that this represents a chance to transform the economy of the region," said Mark Drabenstott, director of the Center for the Study of Rural America at the Federal Reserve Bank of Kansas City. "For regions like northwest Missouri, there is not a long list of economic alternatives."

Despite opposition, Ventria's plans to grow genetically engineered rice - eventually to commercial scale - are going forward. The company began growing rice in North Carolina this summer after getting approval from the Agriculture Department. Once Ventria decides where it will grow rice in Missouri, it will have to apply for a permit from the department, a process expected to take two to three months.

Dean L. Hubbard, president of Northwest Missouri State, persuaded Ventria last year to move its operations from Sacramento to new buildings planned for the Northwest campus in Maryville, about 90 miles north of Kansas City.

Seeking a way to reverse the area's slide in population, Dr. Hubbard teamed up with Melvin D. Booth, a Northwest Missouri alumnus who previously ran two large biotechnology companies. The two approached Ventria about making it part of the university's plan to form joint ventures with young biopharmaceutical companies.

Ventria was already considering similar offers from universities in Georgia, Louisiana and North Carolina, but Scott E. Deeter, Ventria's chief executive, agreed to visit the university last August. Mr. Deeter said that on the ride from the Kansas City airport, he was intrigued when Dr. Hubbard described the university's program to heat and cool the campus using bio-fuel derived from paper and wood chips.

At the meeting, Mr. Garst presented him with a research paper he had prepared on what it would take to grow rice in northern Missouri. "It was very impressive," said Ning Huang, Ventria's vice president for research and development, who was there.

Finally it came down to whether Ventria scientists would agree to move to Maryville, population 10,000, from California. Next year 13 will move, including Dr. Huang.

Under the agreement reached last November, Ventria will pay farmers more than double what they make on their most profitable crop, and pay Northwest Missouri $500 an acre for crops grown on university land. The university is spending about $10 million to help build a production and teaching complex, and the state is kicking in another $10 million.

Atchison County, Mo., where Mr. Garst's farmland is, has lost more than 1,000 people, or 14 percent of its population, since 1990. The town of Watson, once a thriving rural hub with three grocery stores and an opera house, has just over 100 people and no place to buy a soda. Most buildings have been boarded up.

"To reverse the population slide, you have to make it profitable to farm," Dr. Hubbard said. "My dream is that 10 years from now, this rural economy has been transformed, that it is vibrant again and people are renovating their downtowns."

The fate of Mr. Garst's experimental rice plot has loomed larger since Ventria encountered resistance to planting its rice in the southern part of the state, where rice has traditionally been grown.

When the company was considering Missouri as a place to grow its rice, it talked to Anheuser-Busch, which uses Missouri rice in its beer. Mr. Deeter said Anheuser-Busch initially did not raise any opposition to the project. But when Ventria tried to plant rice in southern Missouri this spring, the beer maker threatened not to buy any rice grown in the state. The company feared a consumer backlash if people thought gene-altered rice could end up in their bottles of Bud.

For Missouri's farm economy, the risk of growing pharmaceutical rice is high. More than half of Missouri's rice is sent abroad, to the European Union and Caribbean countries that are especially sensitive about genetically modified products.

"We are still having to make statements to our customers that the rice we export is not genetically modified," said Carl Brothers, the vice president for marketing at Riceland Foods, which markets more than half of Missouri's rice. "We are concerned longer term that if Ventria and others get involved that will get harder to say."

The two companies reached a truce in April: Ventria agreed not to grow genetically modified rice within 120 miles of commercial rice crops. "We can continue to purchase rice grown and processed in Missouri as long as Ventria's growing areas remain sufficiently far from commercial rice production," said Francine Katz, a spokeswoman for Anheuser-Busch.

That deal suddenly made four test plots in the northern part of the state, including Mr. Garst's, all the more important, since Ventria's agreement with Northwest Missouri State calls for the company to grow 70 percent of its rice in the state.

To prove to its customers that it would have a diverse supply base, Ventria must grow in at least one other location in North America, and is also searching for a growing area in the Southern Hemisphere to be able to produce year-round. In June, Ventria planted 70 acres of genetically modified rice in North Carolina. There, environmentalists continue to attack the company, saying the rice poses a threat to other crops and the human food chain.

Ventria's rice fields are just a few miles from a rice-seed-screening research center and are also close to two wildlife refuges with large populations of migrant birds and swans that environmentalists contend could transport Ventria's rice seeds into wild areas. Storms and floods, environmentalists say, could also lead to rice contamination.

"Just washing away in a big rain- storm is enough," said Margaret Mellon, director of the food and environment program at the Union of Concerned Scientists in Washington. Scientists at Ventria, which is yet to make any money from its bio-rice, say rice is among the safest crops for genetic engineering. Rice stalks pollinate themselves, so the altered genes, which are synthetic versions of human genes, cannot be easily transferred to plants in other fields. And Ventria requires farmers to employ a "closed system," using dedicated equipment and a production process where the seed is ground into a powder before it leaves the farm.

But critics say that there is no way to guarantee that the farmers will follow all the government regulations and Ventria's rules, and that they are worried about the risk of contamination because it would be hard to detect. "We simply wouldn't know if a contamination event took place," said Craig Culp, a spokesman for the Center for Food Safety, in Washington.

Dr. Hubbard acknowledged that there are risks, but he said he believed that they were minimal.

Federal regulations have been tested before, most notably in 2002, when drug-producing corn made by ProdiGene began sprouting in soybean fields near its Iowa and Nebraska sites. The Agriculture Department seized 500,000 bushels of soybeans and assessed the company nearly $3 million in fines and disposal costs. Earlier, in 2000, a gene-altered variety of corn that was approved for animal feed but not for human consumption was found in taco shells and other grocery items, prompting recalls.

Mr. Garst is a modern breed of farmer with a master's degree and a healthy interest in science. And he himself has done whatever he can to wring more from his commodity crops, even trying out a $300,000 tractor that steers automatically using a global-positioning satellite to till straighter rows.

"Obviously, you will not see pharmaceutical crops from here to Kansas City," he said of Ventria's project. "But there will be pockets in this area where you will see development. If you keep two more farmers in this area it is huge - there are four of us now."

5. GMO debate comes to Lake County

John Jensen -- Record-Bee staff

LAKE COUNTY -- Genetically engineered crops won't be growing in Lake County anytime soon if local growers have their way.

Lake County supervisors will consider a moratorium on planting of genetically modified, herbicide-resistant alfalfa during the Aug. 23 board meeting.

The Lake County Coalition for Responsible Agriculture (LCCRA) is proposing the moratorium to give the county time to learn more about the benefits and hazards of planting the genetically modified seeds.

LCCRA is a coalition of several groups and numerous individuals, organic farmer Phil Murphy said. "It's Lake County Healthy Environment and Living (HEAL), the Sierra Club, conventional and organic growers," Murphy explained.

Agricultural products using genetically modified organisms (GMOs) are entering mainstream agriculture in the U.S. -- despite resistance to the technology in some parts of the country and in California, where genetically modified, herbicide-resistant alfalfa seeds have been released for sale.

The seeds are the product of Monsanto Co., the same company that makes the commonly used herbicide Roundup. Proponents include the Farm Bureau and Monsanto, who argue that it will increase yields and reduce herbicide use.

"We live in the age of computers. This is just a technological way to increase production using less pesticides," said Lake County Farm Bureau Executive Director Chuck March. "This is just a future step in agriculture."

Detractors of the genetically modified seeds say they will necessitate increased herbicide spraying. They also claim Monsanto's licensing agreement will potentially expose farmers to copyright infringement lawsuits from the company as traditional crops are contaminated by genetically modified crops.

The problem with cross pollination of the crops is that Monsanto doesn't want people stealing its technology and selling the seeds as their own. The thing is, bees pollinate plants, so crops could be pollinated without a human hand in it.

March doesn't see it quite that way. "That's been a scare tactic on the GMO issue," he said. "When Monsanto comes out with a product they have patents on the seed."

One solution, March said, is buffer zones.

Denise Rushing, a walnut grower in Upper Lake, wants to grow organic alfalfa between her walnut trees in a farming process called permaculture.

"Some alfalfa is grown naturally," she explained. "Permaculture no-till agriculture is basically planting grasses with animals that can graze and provide organic enrichment over the soil," she said.

While neighbors planting GMO crops won't eliminate her ability to grow organic, she doesn't like the idea that to protect her crops from somebody else's she would be required to create a buffer zone.

"It doesn't preclude it, it just requires extra work on my side," she said. "It requires a buffer zone so I have to have some of my land out of production."

Supervisors will get to listen to the arguments on Tuesday and decide which way to go. District 1 Supervisor Ed Robey said he wasn't entirely sure why the moratorium was strictly on a single crop.

"If we're going to pass an ordinance on alfalfa, why not on all GMOs, including alfalfa?" he asked.

Robey said he isn't interested in an outright ban on GMOs -- as neighboring Mendocino County put into effect -- but he suggested that the single crop moratorium might not be enough.

"I would prefer to talk about the whole enchilada and not just a bite of it," he said.

6. Scientists warn of GM superweed risk

Paul Brown, environment correspondent
Thursday August 18, 2005
The Guardian
http://www.guardian.co.uk/gmdebate/Story/0,2763,1551238,00.html

Scientists have identified 15 weed species that are resistant to a herbicide widely used on GM crops and are warning farmers they may become a serious problem unless a strategy for dealing with them is developed.

Some of the most common weed species, including types of ryegrass, bindweed and goosegrass either have some strains with a natural resistance to the widely used GM herbicide glyphosate or have developed one.

Writing in the journal Outlooks on Pest Management, four scientists argue there is a danger that by ignoring the threat these weeds pose, farmers may be giving them a huge advantage over other plants which are killed by glyphosate.

Even where they did not previously thrive on farmland or were in a minority of weeds, farmers may be creating a new niche for them among arable crops which would allow them to multiply rapidly.

The paper is published alongside an assessment of the three-year farm-scale trials of GM oilseed rape, sugar beet and maize in Britain. All three crops are glyphosate-resistant and, if the American researchers are right, would be troubled by glyphosate-resistant weeds if grown commercially in the UK.

Glyphosate has been used by farmers to kill off weeds for 30 years but since the 1990s, when GM crops were modified to resist glyphosate, its use has mushroomed.

The paper says that worldwide use has increased from 5,000 tonnes a year in 1995 to more than 30,000 tonnes in 2002, and has increased since.

However, intensive use of the herbicide combined with the non-rotation of glyphosate-resistant GM crops is expected to increase the problem and it will develop on "a global scale," the paper says.

The researchers, based at the State University and the Southern Weed Research Unit in Mississippi, are concerned that the widespread usefulness of an extremely efficient weedkiller will be lost if farmers do not take precautions.

"The problem of glyphosate-resistant weeds is real, and farmers have to realise that the continuous use of glyphosate without alternative strategies will likely result in the evolution of more glyphosate-resistant weeds.

"Even in the short term no one can predict the future loss of glyphosate efficiency due to weed species shifts and evolution of glyphosate resistance," says Vijay Nandula in the conclusion to the paper.

He advises farmers to treat land with additional herbicide to kill off the weeds before they multiply sufficiently to cause a problem.