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Summary Plants integrate environmental stimuli to optimize photosynthesis vs water loss by controlling stomatal apertures. However, stomatal responses to temperature elevation and the underlying molecular genetic mechanisms remain less studied.We developed an approach for clamping leaf‐to‐air vapor pressure difference (VPDleaf) to fixed values, and recorded robust reversible warming‐induced stomatal opening in intact plants. We analyzed stomatal temperature responses of mutants impaired in guard cell signaling pathways for blue light, abscisic acid (ABA), CO2, and the temperature‐sensitive proteins, Phytochrome B (phyB) and EARLY‐FLOWERING‐3 (ELF3).We confirmed thatphot1‐5/phot2‐1leaves lacking blue‐light photoreceptors showed partially reduced warming‐induced stomatal opening. Furthermore, ABA‐biosynthesis, phyB, and ELF3 were not essential for the stomatal warming response. Strikingly,Arabidopsis(dicot) andBrachypodium distachyon(monocot) mutants lacking guard cell CO2sensors and signaling mechanisms, includinght1,mpk12/mpk4‐gc, andcbc1/cbc2abolished the stomatal warming response, suggesting a conserved mechanism across diverse plant lineages. Moreover, warming rapidly stimulated photosynthesis, resulting in a reduction in intercellular (CO2). Interestingly, further enhancing heat stress caused stomatal opening uncoupled from photosynthesis.We provide genetic and physiological evidence that the stomatal warming response is triggered by increased CO2assimilation and stomatal CO2sensing. Additionally, increasing heat stress functions via a distinct photosynthesis‐uncoupled stomatal opening pathway.
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Molecular basis of priming-induced acquired tolerance to multiple abiotic stresses in plants
Abstract The growth, survival, and productivity of plants are constantly challenged by diverse abiotic stresses. When plants are exposed to stress for the first time, they can capture molecular information and store it as a form of memory, which enables them to competently and rapidly respond to subsequent stress(es). This process is referred to as a priming-induced or acquired stress response. In this review, we discuss how (i) the storage and retrieval of the information from stress memory modulates plant physiological, cellular, and molecular processes in response to subsequent stress(es), (ii) the intensity, recurrence, and duration of priming stimuli influences the outcomes of the stress response, and (iii) the varying responses at different plant developmental stages. We highlight current understanding of the distinct and common molecular processes manifested at the epigenetic, (post-)transcriptional, and post-translational levels mediated by stress-associated molecules and metabolites, including phytohormones. We conclude by emphasizing how unravelling the molecular circuitry underlying diverse priming-stimuli-induced stress responses could propel the use of priming as a management practice for crop plants. This practice, in combination with precision agriculture, could aid in increasing yield quantity and quality to meet the rapidly rising demand for food.
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- PAR ID:
- 10474554
- Publisher / Repository:
- Oxford University Press
- Date Published:
- Journal Name:
- Journal of Experimental Botany
- Volume:
- 73
- Issue:
- 11
- ISSN:
- 0022-0957
- Format(s):
- Medium: X Size: p. 3355-3371
- Size(s):
- p. 3355-3371
- Sponsoring Org:
- National Science Foundation
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