AUTHOR=Rong Zi-Yi , Lei An-Qi , Wu Qiang-Sheng , Srivastava Anoop Kumar , Hashem Abeer , Abd_Allah Elsayed Fathi , Kuča Kamil , Yang Tianyuan 

TITLE=Serendipita indica promotes P acquisition and growth in tea seedlings under P deficit conditions by increasing cytokinins and indoleacetic acid and phosphate transporter gene expression

JOURNAL=Frontiers in Plant Science

VOLUME=14

YEAR=2023

URL=https://www.frontiersin.org/journals/plant-science/articles/10.3389/fpls.2023.1146182

DOI=10.3389/fpls.2023.1146182

ISSN=1664-462X

ABSTRACT=<p>The culturable endophytic fungus <italic>Serendipita indica</italic> has many beneficial effects on plants, but whether and how it affects physiological activities and phosphorus (P) acquisition of tea seedlings at low P levels is unclear. The objective of this study was to analyze the effects of inoculation with <italic>S</italic>. <italic>indica</italic> on growth, gas exchange, chlorophyll fluorescence, auxins, cytokinins, P levels, and expressions of two phosphate transporter (<italic>PT</italic>) genes in leaves of tea (<italic>Camellia sinensis</italic> L. cv. Fudingdabaicha) seedlings grown at 0.5 μM (P<sub>0.5</sub>) and 50 μM (P<sub>50</sub>) P levels. Sixteen weeks after the inoculation, <italic>S</italic>. <italic>indica</italic> colonized roots of tea seedlings, with root fungal colonization rates reaching 62.18% and 81.34% at P<sub>0.5</sub> and P<sub>50</sub> levels, respectively. Although plant growth behavior, leaf gas exchange, chlorophyll values, nitrogen balance index, and chlorophyll fluorescence parameters of tea seedlings were suppressed at P<sub>0.5</sub> versus P<sub>50</sub> levels, inoculation of <italic>S</italic>. <italic>indica</italic> mitigated the negative effects to some extent, along with more prominent promotion at P<sub>0.5</sub> levels. <italic>S</italic>. <italic>indica</italic> inoculation significantly increased leaf P and indoleacetic acid concentrations at P<sub>0.5</sub> and P<sub>50</sub> levels and leaf isopentenyladenine, dihydrozeatin, and transzeatin concentrations at P<sub>0.5</sub> levels, coupled with the reduction of indolebutyric acid at P<sub>50</sub> levels. Inoculation of <italic>S</italic>. <italic>indica</italic> up-regulated the relative expression of leaf <italic>CsPT1</italic> at P<sub>0.5</sub> and P<sub>50</sub> levels and <italic>CsPT4</italic> at P<sub>0.5</sub> levels. It is concluded that <italic>S</italic>. <italic>indica</italic> promoted P acquisition and growth in tea seedlings under P deficit conditions by increasing cytokinins and indoleacetic acid and <italic>CsPT1</italic> and <italic>CsPT4</italic> expression.</p>