CHARACTERISTICS OF RESPONSES OF FRUIT TREES TO CLIMATE CHANGES IN JAPAN

Abstract

Agricultural productions are at risk of receiving negative influences from global warming. Japan Meteorological Agency reported that the mean temperature, in Japan had risen at the rate of 1.06°C per 100 years for the 20 th century. To grasp the actual influence of global warming on fruit tree production in Japan, a questionnaire was sent to public institutes of 47 prefectures for fruit tree research. These results indicated that tree species were classified into two types according to responses of fruit development to climate changes. One group was the earlier development type and the other was the prolonged development type. The former included tree species in which both flowering and harvesting periods had accelerated. These were Japanese pears, peaches and Japanese apricots. The latter had tree species in which the flowering period had accelerated, while harvesting period had not accelerated. This type included apples, Japanese persimmons, grapes and satsuma mandarins. Fruit qualities of the prolonged development type had clearly changed, for example coloring disorder, enlarging, reduction of acidity, softening and spoiling rapidly. Freezing injury and late frost damage has increased in northern Japan which is a colder area.