Abstract
High irradiance-acclimated soybean leaves had the same CO(2) exchange rates, but lower starch accumulation rates and correspondingly higher translocation rates than unacclimated leaves. Increased translocation rates were associated with increased sucrose phosphate synthetase (EC 2.4.1.14) activity. Foliar sucrose levels and adenosine diphosphate-glucose pyrophosphorylase (EC 2.7.7.9) activity were unaffected. Carbon assimilation, partitioning, and enzyme activity of unacclimated leaves were unaltered even after a second day's exposure to high irradiance. Results are consistent with the hypothesis that photosynthate partitioning between starch synthesis and sucrose translocation are controlled in part by the rate of sucrose synthesis.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have