ARS | Publication request: FOLIAR AND TUBER BLIGHT RESISTANCE IN A SOLANUM TUBEROSUM BREEDING LINES.

Submitted to: Plant Breeding
Publication Type: Review Article
Publication Acceptance Date: May 1, 2009
Publication Date: June 1, 2009
Citation: Mayton, H., Griffiths, H., Simko, I., Cheng, S., Lorenzen, J., De Jong, W., Fry, W.E. 2009. FOLIAR AND TUBER BLIGHT RESISTANCE IN A SOLANUM TUBEROSUM BREEDING LINES.. Plant Breeding.DOI:10.1111/J.1439-0523.01671.x

Interpretive Summary: Phytophthora infestans, the causal agent of late blight, is the most devastating potato disease worldwide. We have identified the genetic basis of foliar and tuber resistance to the disease in a tetraploid breeding population of potato (Solanum tuberosum). Resistance to the disease was assessed in the field (both foliar and tuber resistance) and in the laboratory (tuber resistance). A locus explaining approximately 50% of the phenotypic variance for the foliar resistance was located on the lower arm of linkage group V. The presence of the locus was confirmed in a separate sample from the same population. Tuber blight detected via laboratory assays did not correlate with tuber blight incidence in the field. Most of the markers associated with the tuber blight resistance were different from those associated with the foliar blight resistance.

Technical Abstract: The purpose of this research was to identify the genetic basis of foliar and tuber resistance to Phytophthora infestans in a potato breeding population developed from a cross between two tetraploid Solanum tuberosum lines, NY121 and NY115. The parent with high foliar resistance, NY121, was highly susceptible to tuber blight. Foliar resistance was assessed in field trials, while tuber blight was assessed both in the field and in the laboratory. A QTL explaining approximately 50% of the phenotypic variance for foliar resistance was located on the lower arm of linkage group V, and was loosely associated with tuber blight resistance (significantly in one of two trials). ¬¬This QTL was confirmed in a separate sample from the same population. Tuber blight detected via laboratory assays was not correlated with tuber blight incidence in the field. Most markers associated with tuber blight resistance were not associated with foliar resistance and most markers associated with foliar resistance were not associated with tuber blight resistance.