|Palta, J -|
|Vega, S -|
Submitted to: HortScience
Publication Type: Abstract Only
Publication Acceptance Date: April 1, 2007
Publication Date: February 1, 2008
Citation: Palta, J.P., Bamberg, J.B., Vega, S.E. 2008. Improving Freezing Tolerance of Cultivated Potatoes: Moving Frost Hardy Genes From Wild Potatoes and Making Real Progress Using Precise Screening Tools [abstract]. HortScience. 43:1108. Technical Abstract: The common cultivated species Solanum tubrosum is frost sensitive and is killed at temperatures below -2.5°C. It has been estimated that by increasing frost hardiness by 1–2 C one can expect an increase in potato yield by 26 to 40% in the Altiplano (Peru and Bolivia) covering 63,000 ha. of potatoes. Because of the threat of frost, 60% of this area is planted with bitter potatoes that are hardy to frost yet cannot be consumed fresh. Early work showed that several wild potato species are hardy under normal growing conditions (non-acclimated frost hardiness: NAF). For example, S. acaule can survive temperatures as low as -5°C. In addition to being hardy some of the wild species such as S. commersonii are able to increase its frost hardiness after a brief exposure to cold temperatures (acclimation capacity: ACC). For example S. commersonii can acclimate in 7 days from -4 to -12°C. Our early research demonstrated that NAF and ACC are independent components under separate genetic control. These results suggested that potato frost hardiness can only be improved through precise selection for both of these components under controlled environments. Furthermore these studies suggested lack of progress with field screening approach. During the last 15 years, using somatic hybrids of S. tuberosum and S. commersonii as well as sexual hybrids with S. acaule, we have made significant progress in moving frost hardiness to the cultivated type. These studies utilized precise screening under controlled environment. Advanced breeding lines with improved frost hardiness (NAF and ACC) as well as tuber yield comparable to cultivated parents have been identified. We are now in the process of utilizing these materials in breeding as well as testing these lines in the field.