Researchers Identify Thermosensitive QTL for Enhanced Tuber Yield in Potato

In potato cultivars, tuber yield is optimal at daytime temperatures ranging from 14–22°C, with further increase in temperature, tuber production is reduced or inhibited. Almudena Trapero-Mozos of the University of St. Andrew in the UK aimed to identify quantitative trait loci (QTL) associated with enhanced potato tuber yield.

A candidate gene, HSc70, was identified within the QTL intervals associated with elevated yield in a hybrid diploid potato population. A particular HSc70 allelic variant was then found to be linked to elevated yield in the population. Expression of the allelic variant was much higher than others, especially when exposed to moderately elevated temperature.

Analysis revealed a repeat element present in the promoter of the variant allele, but not in other HSc70 alleles in the population. Expression of the allelic variant under its native promoter resulted in enhanced expression at elevated temperature. This leads to improved yield under moderately elevated temperature.

These results identify the HSc70 expression as a significant factor influencing yield stability under moderately elevated temperature.

For more on this study, read the article in Plant Biotechnology Journal.