By Dr. Hal Moffitt
In June, Dr. Hal Moffitt plans to begin a series of tests to determine if a cold storage treatment followed by fumigation with methyl bromide will kill codling moth eggs and larvae on Lapins and Chelan cherries.
The tests are required by the Japanese government before those varieties of cherries can be exported to that country, even though the results are a foregone conclusion.
Twenty-four years ago, Moffitt began the first such tests on cherries, using Bing, Van, and Lambert cherries. His work, which established that a cold treatment and fumigation was an effective quarantine measure to prevent live codling moths from being shipped to Japan in those cherry cultivars, led to the first exports of Pacific Northwest cherries being allowed to Japan in 1978.
In the late 1980s, he did similar tests on Rainier cherries, and he is currently repeating the process on Brooks and Tulare, two commercial varieties grown in California.
The Northwest fruit industry would like to be able to ship two new varieties, Lapins and Chelan. Chelan is an early maturing variety, and the Lapins is a large, late season cherry that is expected to appeal to Japanese buyers.
Extensive and expensive tests, each involving tens of thousands of codling moth larvae, have had to be done on each of the four varieties of cherries accepted so far, and will have to be done on each variety the Northwest cherry industry wishes to ship to Japan. Millions of codling moth larvae have been raised at the lab over the years for this purpose.
Never has Moffitt seen any difference in the response of the insect to the treatment, although different cultivars of cherries withstand the fumigation treatment better than others. For example, Rainier cherries seem particularly susceptible, and a bruise on a fumigated cherry shows up immediately.
Moffitt acknowledges that it is useful for the Japanese and for producers to know the effect of the fumigation on fruit quality. But the U.S. government has argued that efficacy studies for each additional cultivar of a fruit that is already approved are unnecessary. A codling moth larva seems to be killed just the same, no matter whether it happens to be on a Bing or a Rainier.
So far, the Japanese government has insisted that U.S. scientists go through the entire process again with every cultivar, and since the lucrative Japanese market is at stake, the United States has had no choice but to comply.
"It's frustrating," Moffitt said. "But they're in the driver's seat. They say this is what you must do."
The Washington Tree Fruit Research Commission has partially funded some of the tests in the past, but the U.S. Department of Agriculture-Agricultural Research Service (ARS) is now requesting that the industry pay a larger part of the cost. The California cherry industry has contributed $50,000 to the ARS for the first year of tests on the Brooks and Tulare cherries, and has agreed to pay a further $25,000 for the confirmatory tests this season.
Moffitt said the ARS will be looking for similar support from the Northwest cherry industry for Chelan and Lapins.
"What's happened is that over the years, inflation and added costs have eaten away at our budget to where we no longer have the funding to carry out studies like this that are very labor-intensive," he said. "We have to rear large numbers of moths, and we just don't have the funding to be able to do that any more."
Ken Severn, president of Northwest Cherry Growers, said in April it had not yet been decided how the tests would be funded.
Similar tests have had to be done to gain access for apples.
Moffitt started work on the protocol for treating apples for Japan in 1969, some 26 years before apples were actually exported to that country. The Japanese government required an unspecified direct postharvest treatment for codling moth. The idea of a methyl bromide fumigation came from the United States, as the fumigant had been used since the 1930s for insect control of fresh fruits and was immediately available.
After the first two years, during which Moffitt used infested fruit from unsprayed orchards for his tests, the project was wound down. He was informed that it was unlikely that the United States would ever present a protocol for exporting apples to Japan because of the sensitivity of the issue at the time. Japan was a large apple-producing country, and the idea of importing apples was politically, economically, and socially sensitive there.
So, in 1972, Moffitt shifted his focus to meeting the quarantine requirements of cherries. It was considered less sensitive, and some Japanese trading companies had shown in interest in importing Northwest cherries. The pests of concern were codling moth and cherry fruit fly.
Moffitt had never seen codling moth on cherries, and was not even sure cherries could be infested for the tests. "It was listed in the literature as being a host, but we had never seen it," he said.
It turned out cherries could be infested with codling moth, and as the research and discussions progressed, the program was expanded. The treatment devised for codling moth also had to be effective against cherry fruit fly. Because of the large numbers of insects needed, he began to rear insects in the laboratory rather than using infested fruit from orchards.
Six years later, the first Northwest cherries were shipped to Japan.
"It was not an easy process, and it was not a timely process," Moffitt recalled. "There were many obstacles that were thrown at us during this research effort that tended to lengthen the period of time from starting the work to getting the treatment accepted by the Japanese."
Moffitt said this was the first time the Japanese had agreed to import a fruit that was a host of codling moth. "We were breaking new ground."
The success with cherries sparked renewed interest in gaining access for apples, but again, progress was slow. The Japanese drew up a list of pests of concern in addition to codling moth. They included the lesser apple worm, which the Northwest fruit industry knew little about. The treatment proposed by the United States had to be effective against the lesser apple worm as well as codling moth, and Moffitt's challenge was to find enough of them for the tests. It had been reported in the eastern United States as a potential pest of apples.
"What we had to do then was to find the insect," Moffitt recalled.
The lesser apple worm is a close relative of the oriental fruit moth. The pheromone of the apple lesser worm had been developed in the process of synthesizing the pheromone of the oriental fruit moth, and so Moffitt was able to use pheromone traps.
He found a few adult moths in northwest Washington but never any larvae. He then focused his search on the Walla Walla and Milton-Freewater area on the Washington-Oregon border, where the lesser apple worm had been reported as a pest of prunes in the 1950s. Although he never found it in wild prune, he began to find the insect in hawthorn, and found enough infested hawthorn berries to begin rearing it in the lab.
"As soon as we started looking in hawthorn, we started picking them up," he said. "We found it's found pretty much everywhere you look, if you look in the right place."
He said it is native to northeastern North America. It evidently moved fairly recently into western fruit growing districts and is still in the process of adapting to commercial fruit crops.
One of the hardest parts of meeting the protocol has been scheduling the infestation and treatment required for the confirmatory tests to coincide with the visit of the required Japanese observer, since the Japanese government has not proven very predictable in scheduling the visits.
It was some time after Moffitt established he had an effective treatment available for both codling moth and the lesser apple worm that the Japanese agreed to schedule the confirmatory tests that paved the way for the opening of the market.
Although the arrival of the first apples was accompanied by great hoopla, for Moffitt it was something of an anticlimax. He and other USDA researchers Dr. Stephen Drake, who had worked on the phytotoxicity studies, and Dr. Rodney Roberts, who had done work to help satisfy Japan's concerns about fireblight, were among the guests at an industry reception in Seattle to mark the event. "That was probably the closest thing we had to a celebration," he said.
The tests on Red and Golden Delicious were just the start, and he is repeating them for Granny Smith, Fuji, Gala, and Jonagold.
"In my view, it's very important, and it's work that has to be done, but it's not research," lamented Moffitt, who said he would rather be working on true research or field work, like he used to do, rather than spending so much time redoing the tests for additional cultivars.
He said there has been some thought devoted to developing the information by some other means, and looking at it more as a demonstration project than research, so that the USDA can be in a better position to meet industry needs.
But foreign governments require that the work be done on a government-to-government level, he said. "There has to be some USDA umbrella over all the work."
Moffitt is planning to retire soon, but is confident that the quarantine work will not end when he leaves. He said it is likely that quarantine issues will become more important than ever under the new World Trade Organization, which replaced GATT (the General Agreement on Tariffs and Trade).
As countries are forced to drop traditional barriers to imports, one of the few ways they can attempt to keep out imported goods is by raising quarantine issues.
"As these concerns are raised by the potential importing country, someone has to develop the information to address that concern," Moffitt explained. "A lot of times, it may be a case of putting together all the information that documents that a direct treatment is not required. But in those cases where you can't support or document that position, there may need to be additional research done."
Severn paid tribute to the work Moffitt has done to gain or maintain access for Northwest cherries in foreign markets.
"Without the leadership of the ARS in this field of foreign market phytosanitary constraints, and without Hal Moffitt working on these problems, the industry would never have shipped to Japan and would not be in a position to solve some of the other issues he has worked on," Severn said.
"He is recognized as a worldwide authority, and when he puts his name on it, it means something not only to our industry but to the people around the world."
