Assessing of the contributions of pod photosynthesis to carbon acquisition of seed in alfalfa (Medicago sativa L.).
The distribution of carbon from a branch setting pod in alfalfa was investigated during the seed development of seeds to determine the relative contribution of pod and leaf photoassimilates to the total C balance and to investigate the partitioning of these photoassimilates to other plant organs. A13Clabeling procedure was used to label C photoassimilates of pods and leaves in alfalfa, and the Δ13C values of a pod, leaves, a section of stem and roots were measured during seed development on day 10, 15, 20 and 25 after labeling of the pod. The results showed that the alfalfa pod had photosynthetic capacity early in the development of seeds, and that pod photosynthesis could provide carbon to alfalfa organs including seeds, pods, leaves, stems and roots, in addition to leaf photosynthesis. Photosynthesis in the pod affected the total C balance of the alfalfa branch with the redistribution of a portion of pod assimilates to other plant organs. The assimilated13C of the pod was used for the growth requirements of plant seeds and pods. The requirements for assimilated C came primarily from the young pod in early seed development, with later requirements provided primarily from the leaf.
Key Laboratory of Eco-Environment-Related Polymer Materials, Ministry of Education of China, Key Laboratory of Gansu Polymer Materials, College of Chemistry and Chemical Engineering, Northwest Normal University, Lanzhou 730070, China.
Wenxu
W
Zhang
Institute of Grassland Science, China Agricultural University, Beijing 100193, China.
Peisheng
P
Mao
Dryland Farming Institute, Hebei Academy of Agricultural and Forestry Sciences, Hengshui 053000, China.
Yuan
Y
Li
Institute of Grassland Science, China Agricultural University, Beijing 100193, China.
Mingya
M
Wang
Institute of Grassland Science, China Agricultural University, Beijing 100193, China.
Fangshan
F
Xia
Institute of Grassland Science, China Agricultural University, Beijing 100193, China.
Hui
H
Wang
D001692:Biological Transport; D002244:Carbon / Q000378:metabolism*; D002247:Carbon Isotopes; D007553:Isotope Labeling; D007700:Kinetics; D000455:Medicago sativa / Q000254:growth & development / Q000378:metabolism*; D009928:Organ Specificity; D010788:Photosynthesis / Q000502:physiology*; D018515:Plant Leaves / Q000254:growth & development / Q000378:metabolism*; D018517:Plant Roots / Q000254:growth & development / Q000378:metabolism*; D018547:Plant Stems / Q000254:growth & development / Q000378:metabolism*; D012639:Seeds / Q000254:growth & development / Q000378:metabolism*
D002247:Carbon Isotopes; D002244:Carbon