Potassium application delays Zhebeimu (Fritillaria thunbergii Miq.) leaf senescence under shade

Honghai Zhu; Huizhen Jin; Dinghao Yang; Leran Wang; Yue Yin; Wenjun Weng; Shumin Wang; Shipeng Jiang; Qiang Yuan; Guilan Duan; Hui Wang; Ning Sui

doi:10.1016/j.plaphy.2026.111084

Potassium application delays Zhebeimu (Fritillaria thunbergii Miq.) leaf senescence under shade

Plant Physiol Biochem. 2026 Jan 30:232:111084. doi: 10.1016/j.plaphy.2026.111084. Online ahead of print.

Authors

Honghai Zhu¹, Huizhen Jin², Dinghao Yang³, Leran Wang⁴, Yue Yin⁵, Wenjun Weng⁶, Shumin Wang⁷, Shipeng Jiang⁸, Qiang Yuan⁹, Guilan Duan¹⁰, Hui Wang¹¹, Ning Sui¹²

Affiliations

¹ Jinhua Academy, Zhejiang Chinese Medical University, Jinhua, China; College of Pharmaceutical Sciences, Zhejiang Chinese Medical University, Hangzhou, China. Electronic address: 2019201015@njau.edu.cn.
² Jinhua Academy, Zhejiang Chinese Medical University, Jinhua, China. Electronic address: jhz99804@163.com.
³ Jinhua Academy, Zhejiang Chinese Medical University, Jinhua, China; College of Pharmaceutical Sciences, Zhejiang Chinese Medical University, Hangzhou, China. Electronic address: 202321124011170@zcmu.edu.cn.
⁴ School of Life Sciences, Zhejiang Chinese Medical University, Hangzhou, China. Electronic address: wanglrnjau@163.com.
⁵ State Key Laboratory of Regional and Urban Ecology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing, 100085, China; University of Chinese Academy of Sciences, Beijing, 100049, China. Electronic address: yueyin@rcees.ac.cn.
⁶ Jinhua Academy, Zhejiang Chinese Medical University, Jinhua, China. Electronic address: wenjunwork02@163.com.
⁷ Jinhua Academy, Zhejiang Chinese Medical University, Jinhua, China. Electronic address: wsm000105@163.com.
⁸ Jinhua Institute for Drug and Food Control, Jinhua, China. Electronic address: jsp1982416@163.com.
⁹ Jinhua Academy, Zhejiang Chinese Medical University, Jinhua, China. Electronic address: yuanqiang0825@sina.com.
¹⁰ State Key Laboratory of Regional and Urban Ecology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing, 100085, China; University of Chinese Academy of Sciences, Beijing, 100049, China. Electronic address: duangl@rcees.ac.cn.
¹¹ Jinhua Academy, Zhejiang Chinese Medical University, Jinhua, China; College of Pharmaceutical Sciences, Zhejiang Chinese Medical University, Hangzhou, China. Electronic address: 13656716323@zcmu.edu.cn.
¹² Jinhua Academy, Zhejiang Chinese Medical University, Jinhua, China; College of Pharmaceutical Sciences, Zhejiang Chinese Medical University, Hangzhou, China. Electronic address: suining_leo@163.com.

PMID: 41666827
DOI: 10.1016/j.plaphy.2026.111084

Abstract

Shade could improve the medicinal quality of Zhebeimu (Fritillaria thunbergii Miq.) bulb, but lead to decreased yield resulting from leaf senescence. Although potassium application can mitigate such yield loss by delaying leaf senescence, the underlying mechanism remains largely unknown. In this two-year field experiment, the widely cultivated variety 'Zhebei 3' was subjected to shade (around 50% shading) from the squaring stage, along with potassium application of 22.5 kg K₂O ha^-1. Shade treatment elevated the levels of senescence-inducing phytohormones [abscisic acid (ABA), salicylic acid (SA), jasmonic acid (JA), and 1-aminocyclopropanecarboxylic acid (ACC, the direct precursor of ethylene)], and reduced anti-senescence phytohormones [auxin (IAA) and cytokinin (CTK)]. It also suppressed the active oxygen scavenging system by lowering the activities of antioxidant enzymes [superoxide dismutase (SOD), peroxidase (POD), catalase (CAT) and glutathione peroxidase (GPX)] and the concentrations of non-enzymatic antioxidants [phenolics, flavonoids, flavones, and ascorbic acid (AsA)], leading to increased accumulation of O₂^- and malondialdehyde (MDA). Furthermore, shade impaired nitrogen assimilation via inhibiting the activities of nitrate reductase (NR), glutamine synthetase (GS), and glutamate synthase (GOGAT), thereby decreasing amino acid and soluble protein contents. These combined effects resulted in reduced chlorophyll contents and early leaf senescence. By contrast, potassium application increased IAA and CTK levels, enhanced activities of antioxidant enzymes (SOD, POD, CAT, and GPX) and contents of non-enzymatic antioxidant including flavonoids [(+)-gallocatechin, aromadendrin, kaempferol, quercetin, and myricetin] and flavones (kaempferol 3-sophorotrioside, astragalin, rutin, nictoflorin, quercetin 3-sophorotrioside, and isoquercitrin), and improved nitrogen assimilation. These changes collectively elevated chlorophyll contents and delayed shade-induced leaf senescence. Overall, this study broadened the understanding of the mechanism of potassium application in alleviating leaf senescence under shade.

Keywords: Chlorophyll; Flavones; Flavonoids; Metabolome; Non-enzymatic antioxidants.