Agribusiness giant Monsanto Co. yesterday announced an agreement to buy 2,300 acres of agricultural-zoned land in Kunia from the James Campbell Company to expand its seed crop operations, including genetically modified corn.

Monsanto, which also has operations on Maui, Moloka'i and Kaua'i, is a leading producer of biotech corn seed crops. Monsanto didn't say what seeds would be grown on the Kunia acreage, but typically about 60 percent of the company's seed crop involves production of seeds genetically modified for purposes such as insecticide resistance. About 10 percent of those crops are used for genetic research, the company said.

Monsanto said it intends to keep the Kunia acreage, which is former sugarcane and pineapple plantation land, in long-term agricultural use. The company also plans to expand its O'ahu work force by 100 or more employees as production is ramped up in the next six months.

"We're extremely pleased to be able to continue our commitment to Hawai'i through this transaction," said Terry Miller, business manager for Monsanto Hawaii. "As an agricultural company, we look forward to keeping these lands in productive agricultural use for the long-term."

About 1,600 acres of the land being acquired are suitable for farming. The remaining 700 acres are expected to remain as open space.

Financial details of the transaction were not disclosed. However, the two plots of former Campbell Estate land were advertised for sale at a combined price of $38.3 million.

The seed-crop sector expenditures rose 12 percent to $70.4 million last year.

The industry provides about 2,000 jobs and generates $144 million in direct and indirect economic activity annually, according to a study released last year by the Hawaii Crop Improvement Association.

The value of the state's seed-crop industry has grown fivefold in the past decade.

That growth, coupled with pineapple grower Del Monte's recent exit from O'ahu, means Hawai'i's seed crop will likely become Hawai'i's biggest individual crop.

Hawai'i is favored by seed-crop growers because of the year-round growing season, fertile soil and isolation from other corn crops. Isolation is useful when growing genetically modified seed because it reduces the chance that the seed might spread accidentally.

Monsanto also said the land it bought includes a former World War II internment camp, which it would work to preserve. A portion of the land also will be used for community initiatives to promote agricultural education and activities, the company said.

"It's good that it's remaining in agriculture," said Matthew Loke, administrator of the state Agricultural Development Division. And, "It's good that it will remain an open area."

Reach Sean Hao at shao@honoluluadvertiser.com.