Fruit yields not very peachy as global warming fallout rises

2005-11-15 From Kyodo News

In what appears to be fallout from global warming, abnormal fruit, including grapes not turning red and peaches with brown flesh, are becoming nationwide occurrences, forcing producers to seek countermeasures.

"If the color is bad, prices are less than half," said researcher Takayoshi Yamane of the Hiroshima Prefectural Agriculture Technology Center's Fruit Tree Research Institute.

Usually large and red, the high-quality Aki Queen grape grown in mild coastal areas in Hiroshima Prefecture along the Seto Inland Sea remained green even in the harvest month of August, apparently because of the high temperatures when the grape should have begun to change color.

Producers are now covering their grapevines to hasten maturity and tearing off bark to concentrate the nourishment in the fruit. The color, however, is an important factor in determining prices.

Yamane said such damage has been reported primarily in the southern part of the prefecture, but it might spread north in the future.

"The sense of crisis over global warming will increase," he said.

In Kumamoto Prefecture, peaches with brown flesh have been conspicuous for about 15 years. They are susceptible to browning amid high temperatures, a phenomenon known as "Mitsu syndrome" attributed to global warming.

The peaches' flesh matures earlier than changes in the color of the bark of their trees. Producers therefore remove covers at an early date, encouraging the bark to change color.

"We are now curbing the outbreak of Mitsu syndrome by these methods, but we are happy if species immune to the syndrome are developed," a prefectural official said.

In recent years, some satsuma oranges have fallen from trees while still green. High temperatures are regarded as the cause, but no effective countermeasures have been found.

Global warming may also force producers to change growing areas.

The fruit tree research institute of the National Agriculture and Bio-Oriented Research Organization in Tsukuba, Ibaraki Prefecture, said the annual average temperature to favorably grow apples is 6 to 14 degrees, but it will top 14 in plains in the central Tohoku region in the 2060s, a temperature not suited to growing apples.

Hokkaido, where low temperatures have not been conducive to apple growing, is expected to get warmer.

According to a study carried out by the research institute last year, global warming has had an influence on fruit in all 47 prefectures.

Rising temperatures may doom some growing areas.

"We have just begun to address the problem," said senior researcher Toshikazu Asakura. "Our target is to develop species that can be grown even if global warming advances."