Understanding this mechanism is an important step towards the future development of heat-tolerant potato plants.
Temperature has a pronounced effect on the formation of potato tubers: when temperature is too high, potato plants form less or no tubers, which can greatly decrease yields. Scientists at the Friedrich-Alexander-University Erlangen Nuremberg (Germany) and the James Hutton Institute have uncovered the genetic mechanism behind the decrease of potato yields under high temperatures, which may help develop heat-tolerant varieties and protect future potato yields.
Potato is a major global food crop and is cultivated for its tubers, underground storage stems that are rich in starch and nutrients. To produce tubers, plants need lower temperature especially during the night. In this study, scientists identified a small non-coding ribonucleic acid (RNA) molecule which represses the expression of the gene responsible for tuberisation.
Dr Csaba Hornyik, a potato geneticist based within the Institute’s Cell and Molecular Sciences group and co-author of the study, said: “Until now we did not know what prevented tuber formation in high heat conditions. Functional studies confirmed the role of this small RNA molecule: when we decreased its level in potato plants, we observed tuber formation even at higher temperatures, which proves the lack of small RNA induced tuber formation under unfavourable conditions.
“Our study demonstrated the relevance and importance of small RNAs in gene regulatory networks controlling key crop traits. Understanding this mechanism is an important step towards the future development of heat-tolerant potato plants.”
The study Post-transcriptional Regulation of FLOWERING LOCUS T Modulates Heat-Dependent Source-Sink Development in Potato, by Günter G. Lehretz, Sophia Sonnewald, Csaba Hornyik, José M. Corral and Uwe Sonnewald, is available online in Current Biology.