Future-proofing potato: Mechanisms and markers for global-warming tolerant ideotypes
Plant Physiology
Final Report Abstract
Potato is the third most important food crop in the world after rice and wheat. Because of its widely distributed cultivation and high yields, it is considered a critical species in terms of food security in face of a growing world population. However, potato is particularly vulnerable to high temperature during various stages of its life cycle. Elevated temperatures strongly suppress tuberisation, negatively affect storage and shelf life of tubers and reduce fitness of seed potatoes. Breeding new heat-stress tolerant cultivars is an urgent need for sustainable increases in potato production, given the negative impact of the rises in temperature due to global warming. In this project, an integrated approach was used that combined physiology, genetics, genomics, metabolomics and natural variation studies to analyze the impact of elevated temperatures on (1) sinksource relations of potato plants, (2) potato tuber development, (3) starch accumulation and tuber quality and (4) tuber dormancy. We have demonstrated that the stress imposed by elevated temperatures during potato development interferes directly with the photoperiodic pathway for tuber induction by suppressing the expression of the output tuberization signal. A special experimental set-up allowed us to separately apply temperature stress to either above- or belowground tissues and thereby to distinguish between source and sink signals. Our results show that elevated temperatures impair photosynthetic assimilate production and partitioning towards tubers together with a decreased expression of the mobile tuberisation signal. Our data led us to conclude that there is a bidirectional signalling between sourceleaves and sink-organs (tubers) and candidate genes were identified which may be involved in the metabolic re-adjustment. We have also shown that natural variation in the expression of proteins encoded by cellular damage amelioration pathways provide an effective protection against heat stress. Finally, we have demonstrated that novel pathways for assimilate distribution, which are highly susceptible to temperature stress, may be the underlying cause of reduced productivity and fitness.
Publications
- (2016) Potato StCONSTANS-like1 suppresses storage organ formation by directly activating the FT-like StSP5G repressor. Current Biology 26, 872-881
Abelenda J.A., Cruz-Oró E., Franco-Zorrilla J.M. & Prat S.
(See online at https://doi.org/10.1016/j.cub.2016.01.066) - (2017) Genome-wide analysis of starch metabolism genes in potato (Solanum tuberosum L.). BMC Genomics 18(1):37
Van Harsselaar JK, Lorenz J, Senning M, Sonnewald U, Sonnewald S
(See online at https://doi.org/10.1186/s12864-016-3381-z) - (2017) Simultaneous silencing of isoamylases ISA1, ISA2 and ISA3 by multi-target RNAi in potato tubers leads to decreased starch content and an early sprouting phenotype. PLoS One 12(7): e0181444
Ferreira SJ, Senning M, Fischer-Stettler M, Streb S, Ast M, Neuhaus HE, Zeeman SC, Sonnewald S, Sonnewald U
(See online at https://doi.org/10.1371/journal.pone.0181444) - (2018) Deciphering source and sink responses of potato plants (Solanum tuberosum L.) to elevated temperatures. Plant Cell Environ. 2018 Jun 5
Hastilestari BR, Lorenz J, Reid S, Hofmann J, Pscheidt D, Sonnewald U, Sonnewald S
(See online at https://doi.org/10.1111/pce.13366) - (2018) Engineering heat tolerance in potato by temperaturedependent expression of a specific allele of HEAT- SHOCK COGNATE 70. Plant Biotechnology Journal 16,197-20
Trapero-Mozos A., Morris W.L., Ducreux L.J.M., McLean K., Stephens J., Torrance L., … Taylor M.A.
(See online at https://doi.org/10.1111/pbi.12760) - 2018. A reversible lightand genotype-dependent acquired thermotolerance response protects the potato plant from damage due to excessive temperature. Planta, 247(6), pp.1377-1392
Trapero-Mozos, A., Ducreux, L.J., Bita, C.E., Morris, W., Wiese, C., Morris, J.A., Paterson, C., Hedley, P.E., Hancock, R.D. and Taylor, M.
(See online at https://doi.org/10.1007/s00425-018-2874-1)
