Tukuli, A. | Search bioRxiv

bioRxiv2023

Rapid systemic responses of Arabidopsis to waterlogging stress

Waterlogging stress (WLS) negatively impacts the growth and yield of crops resulting in heavy losses to agricultural production. Previous studies revealed that WLS induces a systemic response in shoots that is partially dependent on the plant hormones ethylene and abscisic acid. However, the role of rapid cell-to-cell signaling pathways, such as the reactive oxygen species (ROS) and calcium waves, in systemic responses of plants to WLS is unknown at present. Here we reveal that an abrupt WLS treatment of Arabidopsis thaliana plants growing in peat moss triggers systemic ROS and calcium wave responses, and that the WLS-triggered ROS wave response of Arabidopsis is dependent on the ROS generating RESPIRATORY BURST OXIDASE HOMOLOG D (RBOHD), calcium-permeable channels GLUTAMATE-LIKE RECEPTOR 3.3 and 3.6 (GLR3.3 and GLR3.6), and aquaporin PLASMA MEMBRANE INTRINSIC PROTEIN 2;1 (PIP2;1) proteins. We further show that WLS is accompanied by a rapid systemic transcriptomic response that is evident as early as 10 min following waterlogging initiation, includes many hypoxia-response transcripts, and is partially dependent on RBOHD. Interestingly, the abrupt WLS of Arabidopsis resulted in the triggering of a rapid hydraulic wave response and the transient opening of stomata on leaves. Taken together, our findings reveal that the initiation of WLS in plants is accompanied by rapid systemic physiological and transcriptomic responses that involve the ROS, calcium, and hydraulic waves. These findings reveal that systemic plant responses to WLS are rapid and at least partially dependent on cell-to-cell signaling mechanisms.

plant biology↗

bioRxiv2023

The transcriptome of soybean reproductive tissues subjected to water deficit, heat stress, and a combination of water deficit and heat stress.

Global warming and climate change are driving an alarming increase in the frequency and intensity of extreme climate events, such as droughts, heat waves, and their combination, inflicting heavy losses to agricultural production. Recent studies revealed that the transcriptomic responses of different crops to water deficit (WD) or heat stress (HS) is very different from that to a combination of WD+HS. In addition, it was found that the effects of WD, HS, and WD+HS are significantly more devastating when these stresses occur during the reproductive growth phase of crops, compared to vegetative growth. As the molecular responses of different reproductive and vegetative tissues of plants to WD, HS, or WD+HS could be different from each other, and these differences could impact many current and future breeding and/or engineering attempts to enhance the resilience of crops to climate change, we conducted a transcriptomic analysis of different soybean (Glycine max) tissues to WD, HS, and WD+HS. Here we present a reference transcriptomic dataset that includes the response of soybean leaf, pod, anther, stigma, ovary, and sepal to WD, HS, and WD+HS conditions. Mining this data set for the expression pattern of different stress-response transcripts revealed that each tissue had a unique transcriptomic response to each of the different stress conditions. This finding is important as it suggests that attempting to enhance the overall resilience of crops to climate change could require a coordinated approach that simultaneously alters the expression of different groups of transcripts in different tissues in a stress-specific manner. SIGNIFICANCE STATEMENTA reference transcriptomic dataset of different reproductive tissues of soybean subjected to water deficit, heat stress, and their combination, generated by this study, reveals that different tissues display different responses to these stress conditions. Attempting to enhance the resilience of crops to different stress combinations, associated with climate change, might therefore require simultaneously altering the expression of different sets of transcripts in different tissues in a coordinated and stress-specific manner.

plant biology↗