Submitted to: Potato Grower of Idaho
Publication Type: Trade Journal
Publication Acceptance Date: 3/1/1998
Publication Date: N/A
Interpretive Summary: Internal blackspot is a serious defect caused by bruising potatoes during harvest and handling. This article describes research on potato blackspot in progress. A recent field survey in Idaho demonstrated that field maturity and the amount of solids (starch mainly) in the potato tuber were the main factors leading to increased internal bruise susceptibility in both Russet Burbank and Ranger Russet varieties. Attempts to make both of these important varieties resistant through genetic engineering are discussed. New varieties with bruise resistance are nearing release from the cooperative Pacific Northwest potato variety development program. These are described and compared with Russet Burbank.
Technical Abstract: The factors most closely associated with the blackspot bruise potential of Idaho potato fields were vine maturity, specific gravity of the tubers and soil moisture level. A multiple regression of these three independent variables with blackspot potential as the dependent variable gave a correlation coefficient of 0.73. Transgenic clones of Russet Burbank and Ranger Russet incorporating antisense polyphenoloxidase genes have shown reduced blackspot susceptibility. Advanced breeding selections A81473-2 and A82360-7 are resistant to blackspot bruise.