What if…you could spray a naturally-occurring material on a crop that would cause the plants to activate their own defense mechanism to protect against diseases and pests?

What if…this could be done without any genetic alteration of the crop involved?

And what if the process would also enhance plant growth and yield?

A Presidential Green Chemistry Challenge Award for 2001 has been presented for a product said to do all that. Eden Bioscience Corp., a Bothell, Wash. Company was cited for its technical innovation in the development of Messenger, a biochemical pesticide that the Environmental Protection Agency has approved for disease management and yield enhancement in more than 40 crop groupings, plus turf and ornamentals.

The awards are presented by the EPA's Office of Pollution Prevention and Toxics to recognize organizations and individuals successfully research, developing, and implementing outstanding “green” chemical technologies — defined as chemical products and manufacturing processes that reduce or eliminate the use or generation of hazardous substances. It was only the third time an agricultural product company has won the award.

This year's award winners were formally recognized in ceremonies at the National Academy of Sciences at Washington, D.C.

Stephen L. Johnson, EPA assistant administrator for Prevention, Pesticides, and Toxic Substances, said award winners “represent a fundamental shift in thinking,” and that the environmental and economic benefits “can be very powerful.”

Pollution reductions

There are “many examples of green chemistry being used by American industry,” Johnson said, and to date the program has resulted in the elimination of 38 million pounds of hazardous solvents and chemicals from the environment, with a savings of 275 million gallons of water and 88.9 trillion BTUs of energy.

“These results are truly exceptional,” he said.

Accepting Eden's award were Jerry Butler, chief executive officer, and Zhongmin Wei, vice president for research.”

It was Wei, the son of a Chinese family of small farmers, and his Cornell University colleagues who discovered in 1992 that naturally-occurring proteins, called harpins, could trigger plant defense systems while increasing plant biomass, photosynthesis, nutrient uptake, and root development, ultimately resulting in greater crop yield and quality.

Messenger, the first commercial product using the harpin technology, has been in more than 1,000 trials on a wide array of crops throughout the world against a broad spectrum of viral, fungal, and bacterial diseases, including some for which there currently is no effective treatment. It is packaged as wettable dry granules and the resultant spray is effective, Eden says, at low rates — 0.004 to 0.14 pound of harpin protein per acre per season.

It rapidly degrades and has no potential to bioaccumulate or contaminate water. It is produced through a water-based fermentation process that uses no solvents or reagents and generates no hazardous wastes. It is not irritating to eyes or skin and requires no protective clothing. The EPA has determined that it poses no dietary risk and has established an exemption from tolerance requirements for all food commodities.

The major implication of harpin technology, Butler said, is that “it can improve plant health and yield — from roses and other cut flowers to bananas to cotton — and it can be done without the need to genetically alter seed.

Cotton dreams

“2001 was the year that we'd targeted most of our Messenger sales for cotton,” Jerry Butler said at a Washington luncheon prior to the awards ceremony. “But with cotton prices lower than during the Great Depression, it would've been a hard sell.”

Butler showed slides of an cotton Arkansas field in which a section had been treated with the harpin protein.

“The difference between treated and untreated was amazing,” he says.

The field was heavily infested with nematodes, and Messenger, he says, has shown significant differences in plant health and yields where nematodes are a problem.

The first commercial applications of Messenger were on potatoes in Texas, Butler notes. “Results were phenomenal, with yield increases up to 50 percent.”

Tests for rice disease control in the Delta produced good results, he says, as did southern corn trials. Results on Florida citrus were so good, Butler notes, “We've had to put a caution on the label to growers that treated trees may need to be harvested as much as two months early.”

Messenger has already been approved by California's Department of Pesticide Regulation for control of fungal organisms on strawberries. Plants treated with the material were healthier and produced redder, larger fruit, he said.

California crops

“We anticipate approval early next year on Messenger for grapes, and we expect to file for registration on tomatoes, peppers, and other California crops.”

Messenger and other products utilizing the harpin technology “offer unlimited potential for the future of agriculture,” Butler said. “We believe when the history of green chemistry is written, the introduction of Messenger will be the turning point.”

For the last couple of years, Messenger-treated cotton in nematode infested fields produced yields equal to or better than the standard treatment with Temik, and yields from a combination Messenger-Temik treatment were as much as 20 percent above untreated, says Guy Mikel, Eden's director of sales and marketing.

Messenger, as part of an integrated pest management program, can make cotton — even Bt cotton — perform better, he says. “It just generally results in a healthier plant, more able to withstand harmful pathogens, with less hard lock bolls and boll rot.”

One application on rice has produced up to 10 bushels more yield per acre, Mikel says. A single treatment is “generally sufficient” for monocot crops.

Messenger also can be used as a seed treatment for corn, wheat, and rice.

There is a “major program” for peanuts under way this year. “If we can take the science we've seen in the laboratory into the field, Messenger has significant potential for peanut disease control.”

Mark Russell, Eden's business unit manager for the western U.S., says the company plans to file for registration in California on wine, raisin, and table grapes, tomatoes, peppers, and eggplants, with the expectation of approval in time for the 2002 season. Requests for cotton and citrus “will be on the fast track,” also with an eye toward marketing in 2002.

“By the end of 2002, we'll begin the submission process for leafy vegetables, tree nut crops, and stone fruit.

“From asparagus to zucchini, we believe Messenger will find a place with growers who are looking for an edge in producing better crops for a higher end market.”