Genetic Modification of Pineapples Among Research Supported by State

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The state Board of Agriculture has recently approved grants to support the testing of pineapple strains genetically engineered to resist pests and viruses. The approval was given at the board’s December meeting.

The board also gave grants to support development of new ways to control the two leading causes of pineapple crop losses – mealybug wilt and nematodes. Control of these pests is now done primarily with pesticides that the Environmental Protection Agency will be phasing out over the next year or two.

Since the dramatic decline of sugar production in recent years, pineapple has become the single most economically valuable crop grown in Hawai`i. To help keep it viable, the Board of Agriculture at its December meeting approved some $310,000 in research grants to University of Hawai`i professors.

More than $50,000 of those funds went to Brent Sipes and Donald Schmitt of the University of Hawai`i’s Department of Plant Pathology. One project of theirs involves the field testing of pineapples genetically engineered to resist nematodes. The pineapple industry, the Hawai`i Agriculture Research Center, the U.S. Department of Agriculture – Agriculture Research Service, and the University of Hawai`i have together developed a system to genetically alter pineapple to incorporate resistance to nematodes. They filed a provisional U.S. patent for the system on March 29, 1997.

The Board of Agriculture allocated $20,000 for this work. That comes in addition to more than $76,000 that Sipes and Schmitt have already received from other sources to support research into ways of controlling nematodes, including genetic engineering as well as other methods. (Grants include $33,000 from the state Department of Agriculture for greenhouse evaluation of transgenic pineapple plants for nematode resistance; $10,000 from the American Farmland Trust for developing alternatives to Nemacur and Telone II for root knot and reniform nematode control in pineapple; and another $33,316 from the state DOA for further nematode control research.)

Also at the December meeting, Sipes and Schmitt received approval of $37,358 for another project to look at “environmentally sensitive” means of controlling nematodes through chemical or biological means. They will also be looking at soil characteristics that contribute to the proliferation or suppression of nematodes.

Mealybugs

John Hu, associate professor with UH’s Department of Plant Pathology, also received approval for a $134,550, two-year project to detect, characterize, and manage a new virus associated with the mealybug wilt of pineapple (MWP). One of the strategies he intends to employ is again genetic engineering.

Separately, Hu has received $60,000 from the state to study the use of biotechnology in developing bananas resistant to the banana bunchy top virus.

“Currently, [mealybug wilt] is one of the two most important limiting factors for the production of pineapple in Hawai`i,” according to the staff report to the Board of Agriculture recommending approval of the grant. The report went on to say that mealybug wilt can cause crop losses of up to 12.2 tons per acre, or more than 11 percent.

Hu’s research so far has found that that MWP is induced by the interaction of a certain type of plant virus, known as a closterovirus, and mealybugs. Because of this relationship, Hu thinks it may be possible to manage MWP by controlling the closterovirus.

Currently, MWP control relies on the suppression of mealybugs. Since the 1900s, mealybugs have been controlled indirectly by pesticides that target ants, which tend the mealybugs, much as they do aphids. In recent years, many of the most effective ant-control pesticides have been phased out of use by the EPA as a result of health concerns.

Hu’s project is directed at controlling MWP through control of the closterovirus. His objectives include studying the role of the virus in causing of MWP, determining how the virus is transmitted, and developing control strategies to manage MWP. Those strategies may include planting virus-free pineapples, eliminating the virus from the pineapple using tissue culture technology, and genetically engineering pineapple plants to resist the virus. The transgenic research, the submittal states, will be supported in part by a grant from the USDA-ARS.

Marshall Johnson, an entomologist with the UH Department of Entomology, also has been studying ways to control mealybugs. At the December meeting, the BOA approved a $15,000 grant for his project, which is to develop mass rearing and release protocols for a parasitoid Euryhopalus propinquus to control the gray pineapple mealybug.

* * *
Rules Proposed to Limit Fire Ant Imports

At the December meeting, the Board of Agriculture approved a request by the Department of Agriculture’s Plant Quarantine Branch to hold public hearings on rules governing the import of hosts of the red fire ant, Solenopsis invicta.

Currently, there is no state law that restricts the importation of hosts of the red fire ant. Hosts could include soil, plants with soil attached, or baled haw or straw from infested areas. Originally from Brazil, the ants have become established in several states, including California, Florida, Georgia, Tennessee and Texas.

“If introduced into Hawai`i, our agricultural industries will experience additional restrictions on exports to the mainland and foreign destinations due to foreign, federal, and state quarantines initiated to prevent further spread of this pest,” the staff report to the board states. It goes on to note that “Fire ants have a major impact on ground nesting species, such as birds, rodents, and insects. The decimation of insects will reduce the food supply for native wildlife and negatively impact the pollination of native plants.”

On July 19, 1999, the board enacted interim rules to restrict imports of fire ant hosts. These were effective for just 180 days, however.

According to Plant Quarantine officials, at least two other species known as fire ants have already reached Hawai`i, but they do not pose the same risk as Solenopsis invicta.

A date for the public hearing on the proposed rules has not yet been scheduled.

* * * Board Turns Down Request To Import Box Turtle

Once bitten, twice shy. That would describe the Board of Agriculture’s feeling about allowing private collectors to import exotic animals. Years ago, the Board allowed Moloka`i Ranch to import several species of ungulates as stock for game hunters – a move that resulted in the starvation and death of many animals. (See the January 1999 issue of Environment Hawai`i).

Specifically referring to that experience, the board unanimously voted to deny O`ahu turtle collector Terry Carman’s request to import two male white-fronted box turtles, Cuora galbinifrons, at its December meeting. Carman, who has collected turtles and tortoises for six years, told the Board of Agriculture her turtles would not pose a threat to the environment, in part, because the turtles would be securely housed, and, in any event, are slow moving and therefore easily recaptured.

The white-fronted box turtle is being harvested for food at an alarming rate in its home range in Asia, Carman told the board, and immediate action is needed to prevent it from becoming an endangered species. For these reasons, she wished to import two males to breed with two females she obtained before they were restricted by the state Department of Agriculture.

On October 6, Carman’s request was submitted to the Board of Agriculture’s Advisory Subcommittee on Land Vertebrates and the Advisory Committee on Plants and Animals for review and comment. While some subcommittee members were opposed, the Advisory Committee on Plants and Animals Committee voted to recommended approval to the Board of Agriculture after DOA staff added several conditions to the application that addressed containment, health and resale issues.

Land Vertebrate Subcommittee member Sheila Conant, who opposed the proposal, commented that, “If we approve an alien species just because someone wishes to keep it as a pet or as a curiosity, we will open the floodgates to large numbers of similar applications, and we will have no substantive grounds on which we can deny them.” Other members mentioned concerns about possible escape or theft of the turtles.

When the board first reviewed the request on October 28, 1999, Carman was unable to attend the meeting. The request was denied, but was brought to the board for reconsideration at the December meeting when Carman could attend. At that meeting, Carman insisted that there was no chance of the turtles escaping. In any case, she told the board, she, her husband, and all of her turtles and tortoises would be moving to the mainland in a few years.

The board reaffirmed its initial decision to deny, with board members saying that to grant her request would set a bad precedent.

— Teresa Dawson

Volume 10, Number 9 March 2000

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