Karnal Bunt Update

by Teresa Acklin
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Differences arise among U.S. wheat-growing regions over "zero-tolerance" policies.

   Protection of U.S. wheat export business versus the potential “Balkanization” of the U.S. wheat market was the focus of debate over the U.S. Department of Agriculture's proposed rule on controling Karnal bunt in the United States.

   At a public forum in August in Kansas City, Missouri, U.S., state government officials from Kansas, the largest hard red winter wheat state, and other regional industry representives presented their views. Three other forums were scheduled in the states of Arizona, California and New Mexico, parts of which have been under quarantine after the fungus first was identified in Arizona durum seed wheat in early March.

   The U.S.D.A.'s proposed rule would impose varying restrictions based on relative risks within quarantine areas.

   Officials of U.S.D.A.'s Animal and Plant Health Inspection Service presided over the Kansas City forum. Chuck Schwalbe, associate deputy administrator for the Plant Protection and Quarantine section of APHIS, noted conflicting interests and controversial views surrounding the issue and said the agency was looking for a solution that created “the best possible balance.”

   The conflict basically centers on the existing U.S. policy of “zero tolerance and eradication.” Wheat producers and officials from the affected areas, as well as some scientists, have argued that tolerance levels and management programs should be established for Karnal bunt because it is unlikely to be eradicated.

   “The concept of zero-tolerance for KB spores is as unrealistic as the concept of zero-tolerance for ergot ... vomitoxin, aflatoxin or e. coli,” according to Keith Kelly, director of the Arizona Department of Agriculture, in a white paper issued in May.

   Kelly and others also have said U.S.D.A.'s “enormous mobilization” without knowing the extent of the problem raised unnecessary concern among domestic and overseas U.S. wheat customers.

   But the majority of speakers at the Kansas City forum took direct issue with those views. They cited the threat to U.S. export markets and urged APHIS to maintain its current policy, at least until more scientific data became available.

   “Keith Kelly has told me we don't want to get into the Balkanization of wheat in the U.S.,” said Alice Devine, Kansas secretary of agriculture. “But until you (APHIS) have the data, we don't want you to move one inch.”

   Ms. Devine submitted into the record written comments from Pat Roberts, chairman of the U.S. House Agriculture Committee and a representative of the First District of Kansas. Mr. Roberts noted the importance of export markets to the U.S. wheat economy and the concerns over Karnal bunt raised by overseas customers.

   “The U.S. wheat industry simply and logically cannot afford to risk losing entire markets,” Mr. Roberts wrote. “But that is what is at risk if we let our guard down and abandon the 'zero-tolerance' policy.”

   Charles Deyoe, director of the International Grains Program at Kansas State University in Manhattan, said no single issue had caused more concern among 38 U.S. wheat-buying countries.

   “Their perception is that it's a very serious problem,” Mr. Deyoe said. “And if it's a very serious problem for them, it's a very serious problem for the U.S. wheat industry.”

   Tom Sim, administrator of the plant protection and weed control section of the Kansas Department of Agriculture, said some scientists supporting tolerance levels had put the probability of a widespread outbreak of Karnal bunt at one in 1 million years. But Mr. Sim noted that the assessments did not address when the first event would occur.

   “What if it's next year?” he asked. “Those outside the regulated area must not be expected to assume the risk.”

   Under the proposed rule, individual fields in the two highest risk levels would be prohibited from planting “host crop” wheat in the 1996-97 season. But Mr. Sim argued that a one-year ban was inadequate to assure the plant pathogen was eliminated and recommended a five-year prohibition. Mr. Sim also said management of the rule would be difficult on a field by field basis and called on APHIS to establish broader restricted areas in the affected regions which have non-agricultural physical boundaries such as deserts to contain Karnal bunt.

   Ray Elliott, assistant director of plant industry and consumer services for the Oklahoma Department of Agriculture, urged APHIS to find a solution that would maintain export markets and allow farmers in quarantined areas to market their wheat. He reported that the state had collected 417 samples representing more than 99% of Oklahoma wheat production. Of the total, 416 samples were negative for Karnal bunt.

   One sample was suspect, Mr. Elliott said, because of the presence of a single small spore of some type. But he added that scientists had been unable to identify the spore as Karnal bunt after eight weeks of testing.

   In response to a question from the APHIS panel, Mr. Elliott said 12 Oklahoma companies owning some of the larger grain storage facilities did not participate in the sampling survey. Most were concerned that if a spore were found, U.S.D.A.'s compensation and indemnification programs would be inadequate to protect them from economic damage.

   “We have large elevators in Oklahoma, some up to (408,000 tonnes),” Mr. Elliott said. “U.S.$20,000 (the maximum amount of compensation) is not enough money to clean even a (2,700-tonne) house.”

U.S.D.A. seeks risk assessment factors in Karnal bunt control.

   The U.S. Department of Agriculture has proposed that restrictions imposed to control Karnal bunt disease be determined by the relative risks posed within quarantined areas. Under existing, interim regulations, wheat and millfeed from all U.S. quarantined areas are subject to the same restrictions, regardless of the relative risk involved (see May 1996 World Grain, page 27).

   “We are proposing to establish criteria for levels of risk for areas with regard to Karnal bunt, and to establish criteria for seed planting and movement of regulated articles based on those risk levels,” the Animal and Plant Health Inspection Service said. “We believe this action is warranted because it would relieve unnecessary restrictions on areas regulated because of Karnal bunt, while guarding against the spread of that disease.”

   In the notice, APHIS acknowledged that its interim quarantine actions were considered “necessary ... to guard against the artificial spread of the disease. However, based on subsequent information ... we believe that establishing levels of risk for fields and regulated articles is warranted, and would be adequate in protecting against the artificial spread of Karnal bunt.”

   In addition to retaining the general criteria for regulating a state or part of a state, the proposal would establish criteria for classifying regulated fields according to the following five risk categories:

   1. Fields in which pre-harvest samples tested positive for Karnal bunt.

   2. Fields known to be planted in the past five years with seed contaminated with Karnal bunt.

   3. Fields adjacent to fields in which pre-harvest samples tested positive.

   4. Fields associated only through ownership, management, the movement of equipment, or proximity within a distinct definable area with fields in which pre-harvest samples tested positive.

   5. Fields within a regulated area that are not fields described in “2” or “4” above, and that are part of a distinct, definable area that includes no fields in which pre-harvest samples tested positive for Karnal bunt.

   Under the proposal, wheat, durum wheat and triticale could not be planted in 1996-97 in fields where official samples tested positive for Karnal bunt, or in fields planted in the past five years with seed contaminated with Karnal bunt. Also, the seed must have been treated with a registered fungicide and “sampled and tested negative for Karnal bunt.”

   While existing interim regulations required that millfeed from grain moved interstate from a quarantined area be treated with heat, APHIS said it believed that “millfeed from grain from certain fields in regulated areas poses such an insignificant risk of spreading Karnal bunt that it need not be heat-treated.”

   Under the proposal, millfeed would have to be heat-treated only if the grain involved was from a field in one of the first four risk categories listed above.

   Similar restrictions would be initiated for cleaning and disinfection of farm equipment, grain elevators and transportation equipment.