A corn virus that plagued Kaua'i in the early 1990s has resurfaced, but maize chlorotic mottle is "still in a fairly isolated geographical area," Pioneer Hi-Bred official Cindy Goldstein said.

"We're certainly carefully monitoring this," said Goldstein, the company's manager of international business and community outreach. She said it is "not a concern for hobby farmers" or other agricultural practitioners.

Weather patterns in 2009 were similar to 1989, including a wet fall season, which would explain the "explosion of insects" that transmit the virus from one plant to another, said Dr. Jeri Ooka, Kaua'i Agricultural Research Center associate plant pathologist.

Because there has been "exponential growth" in the seed industry since it first arrived on island in 1969, the virus has not had such detrimental effects as it did in the early 1990s when it was still a "small industry," Ooka said. Now, corn is a dominate player on the West side.

Although the disease never really went away, it was controlled for 20 years, Ooka said.