Translocation of C-13-assimilates in the spring following fall assimilation of (CO2)-C-13 by ';Nijisseiki'; pear (Pyrus pyrifolia Nakai)

作者：Teng YW^*; Tanabe K; Tamura F; Itai A

来源：Journal of the Japanese Society for Horticultural Science, 1999, 68(2): 248-255.

• fruit development
• carbohydrate reserves
• distribution of C-13
• Pyrus pyrifolia

Three-year- old ';Nijisseiki'; pear (Pyrus pyrtfolia Nakai) trees were treated twice with (CO2)-C-13 in October (fall). The distribution of labeled C-13 within the tree during dormancy and remobilization in the following season were determined. After leaf-fall, about 63% of the total C-13 recovered from the tree was distributed in the roots. At anthesis the (13) C content from the previous season';s organs showed a significant decrease: the aerial organs decreased by about 53% and the roots by nearly 60%. About 35% of the total C-13 recovered from the trees after leaf-fall was consumed by respiration until anthesis. New shoot, flower, and root growth accounted for 8.5%, 9.9%, and 3.9% of the total (13) C recovered from the tree after leaf-fall, respectively. One month after anthesis, the C-13 remaining in the previous season';s organs, had further decreased, having been exported to the new leaves and current shoots. The C-13 remaining in the fruitlets dramatically decreased because of the abscission of sepals, petals, stamens, and partial pistils (style and stigma). New roots had the highest concentration of C-13 among all new organs. These data suggest that root systems play a special role in the storage of carbohydrates in young pear trees. All organs depend on carbohydrate reserves for spring growth, especially new roots which seem to depend on reserves for a longer time.

• 出版日期1999-3