title: Carbon autonomy of reproductive shoots of Siberian alder (Alnus hirsuta var. sibirica).
abstract: Carbon autonomy of current-year shoots in flowering, and of current-year shoots plus 1-year-old shoots (1-year-old shoot system) in fruiting of Siberian alder (Alnus hirsuta var. sibirica) was investigated using a stable isotope of carbon, (13)C. The current-year shoot and 1-year-old shoot systems were fed (13)CO(2) and the atom% excess of (13)C in flowers and fruits was determined. The majority of photosynthate allocated to flower buds was originally assimilated in the leaves of the flowering current-year shoots. Of all the current-year shoots on fruiting 1-year-old shoots, only those nearest to the fruits allocated the assimilated photosynthate to fruit maturation. These results indicate that the current-year shoots and 1-year-old shoot systems are carbon-autonomous units for producing flowers and maturing fruits, respectively.
authors.affiliation: Laboratory of Forest Ecology, Division of Environmental Science and Technology, Graduate School of Agriculture, Kyoto University, Kyoto, Japan. shasegaw@ees.hokudai.ac.jp
authors.forename: Shigeaki
authors.initials: S
authors.lastname: Hasegawa
authors.forename: Keisuke
authors.initials: K
authors.lastname: Koba
authors.forename: Ichiro
authors.initials: I
authors.lastname: Tayasu
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Takeda
authors.forename: Hiroki
authors.initials: H
authors.lastname: Haga
mesh_terms: D029661:Alnus / Q000378:metabolism*; D002244:Carbon / Q000378:metabolism*; D002247:Carbon Isotopes; D035264:Flowers / Q000378:metabolism; D005638:Fruit / Q000378:metabolism; D018520:Plant Shoots / Q000378:metabolism*; D012621:Seasons
chemical_list: D002247:Carbon Isotopes; D002244:Carbon