|Budget Amount *help
¥3,500,000 (Direct Cost: ¥3,500,000)
Fiscal Year 2002: ¥1,400,000 (Direct Cost: ¥1,400,000)
Fiscal Year 2001: ¥2,100,000 (Direct Cost: ¥2,100,000)
With 'Asami Red', transpiration was greater than water uptake autumn to winter. Water balance rapidly decreased and vase like deteriorated. Increased transpiration resulted when relative humidity decreased in postharvest. This was related to the increase in water loss from leaves. Although water uptake and transpiration with 'Tineke' increased from autumn to winter, the water uptake always exceeded the transpiration, the vase life was not shortened unlike 'Asami Red'. Moreover, water loss of detatched leaves was constant through out the year. The increase in transpiration was due to the increased leaf area rather than to the decrease in postharvest humidity. RNA-Ag+tris treatment at harvest consistently improved vase life of both cultivars. Especially this was true from autumn to spring, the effect on vase life was higher in 'Asami Red' than in 'Tineke'.
Brittle leaves of 'Asami Red' developed in November when air humidity under production increased. The degree of development was related to high air humidity during the early development of the leaves.
Transpiration of cut 'Asami Red' flowers with brittle leaves was high. The water balance decreased at an early stage and vase life was short. It was observed that brittle leaves developed at lower nodes of the stem, and that vase life was improved by removing the leaves below the 3rd node. RNA・Ag+tris treatments inhibited excessive water loss not only from individual brittle leaves, but also from cut flowers with brittle leaves, which resulted in improved vase life.
Vase life and water characteristics of cut rose flowers harvested in winter differed between cultivars. Although more brittle leaves occurred in this cultivars with many stomata, water balance and vase life was affected not by the number, but by the response of stomata.