Source-sink imbalance increases with growth temperature in the spring geophyte Erythronium americanum.

ABSTRACT: Spring geophytes produce larger storage organs and present delayed leaf senescence under lower growth temperature. Bulb and leaf carbon metabolism were investigated in Erythronium americanum to identify some of the mechanisms that permit this improved growth at low temperature. Plants were grown under three day/night temperature regimes: 18/14 °C, 12/8 °C, and 8/6 °C. Starch accumulated more slowly in the bulb at lower temperatures probably due to the combination of lower net photosynthetic rate and activation of a 'futile cycle' of sucrose synthesis and degradation. Furthermore, bulb cell maturation was delayed at lower temperatures, potentially due to the delayed activation of sucrose synthase leading to a greater sink capacity. Faster starch accumulation and the smaller sink capacity th

SUBMITTER: Gandin A 

PROVIDER: S-EPMC3130172 | biostudies-literature | 2011 Jun

REPOSITORIES: biostudies-literature