AUTHOR=Hu Haichao , He Beibei , Ma Lei , Chen Xin , Han Peilin , Luo Yingli , Liu Yonghong , Fei Xitong , Wei Anzhi 

TITLE=Physiological and transcriptome analyses reveal the photosynthetic response to drought stress in drought-sensitive (Fengjiao) and drought-tolerant (Hanjiao) Zanthoxylum bungeanum cultivars

JOURNAL=Frontiers in Plant Science

VOLUME=13

YEAR=2022

URL=https://www.frontiersin.org/journals/plant-science/articles/10.3389/fpls.2022.968714

DOI=10.3389/fpls.2022.968714

ISSN=1664-462X

ABSTRACT=<p>As an important economical plant, <italic>Zanthoxylum bungeanum</italic> is widely cultivated in arid and semi-arid areas. The studies associated with photosynthesis under drought stress were widely carried out, but not yet in <italic>Z. bungeanum</italic>. Here, the photosynthesis of two <italic>Z. bungeanum</italic> cultivars (FJ, <italic>Z. bungeanum</italic> cv. “Fengjiao”; HJ, <italic>Z. bungeanum</italic> cv. “Hanjiao”) was analyzed under drought stress using physiological indicators and transcriptome data. Drought decreased stomatal aperture and stomatal conductance (Gsw), reduced transpiration rate (E) and sub-stomatal CO<sub>2</sub> concentration (Ci), and lowered chlorophyll and carotenoid content, which reduced the net photosynthetic rate (Pn) of <italic>Z. bungeanum</italic>. The higher photosynthetic rate in HJ stemmed from its higher chlorophyll content, larger stomatal aperture and Gsw, and higher Ci. Weighted gene co-expression network analysis (WGCNA) identified several ABA signal transduction genes (<italic>PYL4</italic>, <italic>PYL9</italic>, and <italic>PYR1</italic>), LCH-encoding genes (<italic>LHCB4.3</italic>), and chlorophyll metabolism genes (<italic>CRD1</italic>, <italic>PORA</italic>, and <italic>CHLH</italic>). Additionally, seven transcription factor genes were identified as important factors regulating photosynthesis under drought conditions. In general, a photosynthetic response model under drought stress was built firstly in <italic>Z. bungeanum</italic>, and the key genes involved in photosynthesis under drought stress were identified. Therefore, the results in our research provide important information for photosynthesis under drought and provided key clues for future molecular breeding in <italic>Z. bungeanum</italic>.</p>