Environment campaigners in Japan are asking the public to plant sunflowers to help decontaminate the soil of whatever radioactive material that seeped through the ground.

Fukushima prefecture's young entrepreneurs and civil servants groups have distributed sunflower seeds to the stricken area to help lessen the radioactive contaminants in the soil.

"We will give the seeds sent back by people for free to farmers, the public sector and other groups next year," said project leader Shinji Handa in an interview. "The goal is a landscape so yellow that it will surprise even NASA. The sunflower is a new symbol of hope and reconstruction and to eventually lure back tourists."

Almost 10,000 packets of sunflower seeds at 500 yen (S$7.70) each have so far been sold to some 30,000 people, including to the city of Yokohama near Tokyo, which is growing sunflowers in 200 parks, Mr Handa said.

New reconstruction minister

Prime Minister Naoto Kan has chosen disaster management minister Ryu Matsumoto as the minister in charge of reconstruction from the March 11 quake and tsunami, reports said on Friday.

Mr Matsumoto, who also serves as an environment minister, will officially take up the new portfolio on Monday, according to major local media, including Jiji Press, public broadcaster NHK and the Nikkei financial daily.

The senior ruling party lawmaker has been in charge of programmes to remove debris and to deliver aid to tens of thousands of people living at evacuation shelters, NHK said.

Mr Kan decided to give 60-year-old Mr Matsumoto the new post to ensure continuity in those programmes, the report said.