Last year marked a sixth consecutive year of dramatic growth for Hawaii seed crop producers, according to a recent government estimate, though the industry dominated by seed corn may be nearing maturity.

The Hawaii office of the National Agricultural Statistics Service reported the value of the local seed crop industry rose 26 percent to $223 million in 2009 from $177 million the year before.

The gain further ingrains seeds as Hawaii’s largest crop by value, a spot seeds have held since pineapple was dethroned in 2006, though other crops contribute more to the local food supply and commercial sales.

Industry observers expect the strong pace of expansion, which began five years ago after hovering around $50 million for several years before that, will begin to cool as the industry matures.

Last season’s big jump reflected expansion of operations by some producers after large land acquisitions in recent years that allowed the companies to build up research and farming, according to Fred Perlak, president of the industry’s trade group, the Hawaii Crop Improvement Association.

"I think what you’re seeing here is the maturing of the acquisitions in the last two or three years," said Perlak, who is also vice president of research and business operations for Monsanto in Hawaii.

Shipments of seed totaled 11.9 million pounds last year, up 6 percent from 11.3 million pounds the year before. Land devoted to seed crops totaled 6,630 acres, up 11 percent from 5,990 acres.

Industry value was up significantly more than production because of how value is calculated by the Agricultural Statistics Service, a part of the U.S. Department of Agriculture. Unlike other crops where value is measured by sales, the seed industry is measured by operating expenses, excluding land purchases, because the seed produced isn’t sold.

Seed production primarily involves studying plant genes and properties, breeding plants with desired genes both traditionally and using biotechnology, testing the resulting plants, and growing large quantities of favorable plants to produce parent seed that is sent to the mainland for mass reproduction and sale to farmers.

Corn represents the core seed product in Hawaii, representing $214 million of the industry’s value last year, though seeds from other plants such as soybean, wheat, sunflower, rice, rapeseed and sorghum have been produced in the past and last year represented $9 million of industry value.

Hawaii is a popular setting because corn can be planted and raised to maturity three or four times in one year compared with only once on the mainland, thereby allowing faster advancement of research.

Five seed companies — BASF, Dow AgroSciences, Monsanto, Pioneer Hi-Bred International and Syngenta — operated 11 farms last year, up from 10 farms the year before.

James Brewbaker, a professor of plant breeding and genetics at the University of Hawaii, has predicted that annual spending by the state’s seed crop producers could level off between $200 million and $250 million — around the annual average value of sugar cane production in the 1980s before its precipitous decline.