Submitted to: American Society of Beet Sugar Technologists Proceedings
Publication Type: Proceedings
Publication Acceptance Date: 3/1/2003
Publication Date: 6/30/2003
Citation: Trebbi, D., Mcgrath, J.M. 2003. Sucrose accumulation during early sugar beet development. American Society of Beet Sugar Technologists Proceedings. p. 267-271.
Technical Abstract: This study examined sucrose accumulation in different breeding lines during the first weeks after emergence in order to identify early physiological differences correlated with root sucrose content. At each weekly harvest during the first 10 weeks of growth, roots, leaves, and hypocotyls were weighed and freeze-dried, and hypocotyls diameters were measured. Sucrose was extracted from freeze-dried roots, with 80% ethanol and then analyzed with high pressure liquid chromatography (HPLC). Sucrose concentration expressed as fresh weight increased from less than 0.5% at the third week (all germplasm) to over 12% by the tenth week, with measured sucrose levels proportional to those from field-harvested beets. Incremental changes in sucrose levels were not constant during this period, but followed a step-wise trend of rapid sucrose accumulation alternating with low sucrose accumulation. Sucrose concentration expressed as dry weight reached 55% at the 10th week for all lines. During this early developmental stage, a time-course differential gene expression analyses (cDNA-AFLP) was performed, and showed that more than 40% of the transcribed genes are differentially expressed in developing roots. Differential gene expression analyses combined with examination of anatomical differences of root tissues during these alternate developmental stages may provide additional insight on the kinetics and molecular mechanisms of sucrose accumulation in sugar beet.