Five construction companies planning to engage in farming are among projects by 95 entities that won government approval Tuesday in special economic zones eligible for preferential deregulatory treatment.

The construction companies are seeking a new source of revenue in response to declining public works projects resulting from the efforts of the national and local governments to tighten spending, government officials said.

Among these construction companies is one in Okuchi, Kagoshima Prefecture, that plans to grow sweet potatoes and other crops on unused farm land between April and June when demand for construction work declines, the officials said.

A construction firm in Otoyo, Kochi Prefecture, plans to grow organic rice, and two firms in Shimane Prefecture will grow rice, feed crops and vegetables in the towns of Ama and Sakurae.

The fifth construction firm, in Itoigawa, Niigata Prefecture, will start wet-rice farming to keep cultivation in the area.

Among other projects, 32 education-related projects were approved ahead of April, when the new school year begins.

The government of Prime Minister Junichiro Koizumi is proceeding with the creation of special deregulatory zones to help boost stagnant regional economies.