ARS | Publication request: Development of markers for Delta9-Stearoyl-ACP-Desaturase (SAD) to screen for cold acclimation

Submitted to: Potato Association of America Proceedings
Publication Type: Abstract Only
Publication Acceptance Date: May 4, 2011
Publication Date: February 1, 2012
Citation: Fei-Li, L., Jin, Z., Vega, S.E., Bamberg, J.B., Palta, J.P. 2012. Development of markers for Delta9-Stearoyl-ACP-Desaturase (SAD) to screen for cold acclimation [abstract]. Potato Association of America Proceedings. Paper. No. 66.

Technical Abstract: Delta 9-Stearoyl-acyl carrier protein (ACP) desaturase (SAD) is an important enzyme of fatty acid biosynthesis in higher plants. Located in the plastid stroma, SAD catalyzes the desaturation of stearoyl-ACP to oleyl-ACP. SAD plays a key role in determining the ratio of saturated fatty acids to unsaturated fatty acids in plants and this ratio is closely related to many functions of plants, especially to the acclimation to low-temperature. We have previously shown that an increase in delta 9 desaturase gene transcripts during cold acclimation is associated with the cold acclimation and thereby increase in freeze tolerance in potatoes. The objective of the present study is to develop molecular markers based on SAD gene to screen potato germplasm for cold acclimation. Two potato species with different levels of freezing tolerance and cold acclimation capacity were used; S.commersonii (freezing tolerant and able to cold acclimate) and S.cardiophyllum (freezing sensitive, unable to cold acclimate). We have designed seven pairs of primers based on the sequence of SAD gene. From the comparison of the PCR products of the two species, using two of the primers, we detected 28 SNP sites for this gene. The sequences including SNP were analyzed by dCAPS Finder 2.0 to look for appropriate restricted enzymes. Analyses of the restriction enzymes products (Mfe I and EcoR I) revealed distinct differences among the two species. These markers are being tested for the development of screening tools using a segregating population derived from commersonii x cardiophyllum.