Response of phytohormone homeostasis to heat stress and the roles of phytohormones in rice grain yield: a review
- Subject Areas
- Agricultural Science, Plant Science, Environmental Impacts
- Rice grain yield, Heat stress, Spikelet fertility, Grain weight, Spikelets per panicle, Phytohormone homeostasis
- © 2019 Wu et al.
- This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, reproduction and adaptation in any medium and for any purpose provided that it is properly attributed. For attribution, the original author(s), title, publication source (PeerJ Preprints) and either DOI or URL of the article must be cited.
- Cite this article
- 2019. Response of phytohormone homeostasis to heat stress and the roles of phytohormones in rice grain yield: a review. PeerJ Preprints 7:e27843v1 https://doi.org/10.7287/peerj.preprints.27843v1
Rice is highly susceptible to heat stress at the reproductive stage. In this review, we first summarize recent progress in heat effects on rice grain yield during different reproductive stages. Different responses of yield traits of rice to heat stress during different reproductive stages are identified. The number of spikelets per panicle is reduced by heat stress during the early reproductive stage but is not affected by heat stress during the mid-late reproductive stage. Spikelet sterility induced by heat stress can be attributed primarily to physiological abnormalities in the reproductive organs during flowering but attributed to structural and morphological abnormalities in reproductive organs during panicle initiation. The lower grain weight caused by heat stress during the early reproductive stage was due to a reduction in non-structural carbohydrates, undeveloped vascular bundles, and a reduction in grain length and width, while a shortened grain filling duration, reduced grain filling rate, and decreased grain width affect grain weight when heat stress occurs during grain filling. Phytohormones play vital roles in regulating plant adaptations against heat stress. We discuss the processes involving phytohormone homeostasis (biosynthesis, catabolism, deactivation, and transport) in response to heat stress. It is currently thought that biosynthesis and transport may be the key processes that determine phytohormone levels and final grain yield in rice under heat stress conditions. Finally, we prospect that screening and breeding rice varieties with comprehensive tolerance to heat stress throughout the entire reproductive phase could be feasible to cope with unpredictable heat events in the future. Studies in phytohormone homeostatic response are needed to further reveal the key processes that determine phytohormone levels under heat condition.
This is a submission to PeerJ for review.