|Budget Amount *help
¥1,700,000 (Direct Cost: ¥1,700,000)
Fiscal Year 1991: ¥500,000 (Direct Cost: ¥500,000)
Fiscal Year 1990: ¥1,200,000 (Direct Cost: ¥1,200,000)
a. ^<14>C-Assimilates partitioning and its metabolism in melon and cucumber plants.
Effect of leaf position on the main stem on the distribution of ^<14>C-assimilates into melon fruits on the lateral shoot was little detected. ^<14>C-assimilates produced in the ^<14>CO_2-fed-leaf translocated to petiol, stem just below the ^<14>CO_2-fed-leaf, leteral shoot with fruit, peduncle and fruit. In these tissues, distributions of ^<14>C in fructose, glucose, sucrose and oligosaccharides fractions were investigated. Percentage distribution of ^<14>C in oligosaccharides fraction decreased gradually, in the tissues along the translocation route, in melon and cucumber plants, but the percentage values were always higher in melon plant compared with cucumber plant. Percentage distributions of ^<14>C in sucrose and monosaccharides fraction increased in the tissues along the translocation route, in both of melon and cucumber plants. These results suggest that the translocation substances could be meta
bolized in the tissues along the translocation route, and the degradation activity in melon differed to cucumber.
b. Metabolism of assimilates in grapevine.
Translocation substance in grape-vine was reported as sucrose, but in the shoots 2-3 weeks after. full bloom, the sugars translocated fbom ^<14>C0_2-fed-leaf to the bark of stem was mainly monosaccharides in 'Delaware' while mainly sucrose in 'Concord'. In the peduncle and fruits in both cultivars, no or little ^<14>C-sucrose was detected. These results suggests that the degradation activity of translocation substances in the tissues along the translocation route are varying with cultivars.
c. Estimation of maturity of 'La France' pear fruit by I_2-starch reaction.
Fruits of European pear 'La France' are harvested about 165 days after full bloom, in Yamagata Prefecture in Japan, but the fruits quality after ripening are not similar by years. For the estimation of the maturity of the fruits, color of the I_2-strach reaction 15 min after painting of the reagent is the most practical methods. Based on the investigation of the starch content in the growing and maturing fruits for five years from 1986-1991, it was considered that the quantity of accumulated starch in flesh of fruits until the end of August and the decreasing speed of the starch from middle September to the beginning of October have to be measured to estimate the fruit maturity. Development of the practical method to estimate the degradation speed of starch by I2-starch reaction was tried. Less