TY - JOUR
T1 - Stomatal and non-stomatal regulations of photosynthesis in response to salinity, and K and Ca fertigation in cotton (Gossypium hirsutum L cv.)
AU - Ma, Yingying
AU - Yuan, Zuoqiang
AU - Wei, Zhenhua
AU - Yan, Fei
AU - Liu, Xuezhi
AU - Li, Xiangnan
AU - Hou, Jingxiang
AU - Hao, Zhanqing
AU - Liu, Fulai
N1 - Publisher Copyright:
© 2025 The Authors
PY - 2025/2
Y1 - 2025/2
N2 - To study the response of photosynthesis of cotton plants to salinity, and K and Ca fertigation, leaf gas exchange, light and CO2 response curves, chlorophyll fluorescence parameters, leaf N, P, Mg, K, Na and Ca concentrations, and antioxidant enzyme activities were measured. Cotton plants were grown at either 0 or 150 mM NaCl salinity (C and S treatment, respectively), and fertigated with or without K and Ca addition (O and K+Ca treatment, respectively). The results showed that 150 mM NaCl salinity decreased stomatal conductance (gs), transpiration rate (Tr) and chloroplast CO2 concentration (Cc). Yet it increased light saturated photosynthetic rate (AL), CO2 saturated photosynthetic rate (AC), mesophyll conductance (gm), maximum electron transport rate (Jmax), maximum Rubisco carboxylation rate (Vcmax) and triose phosphates use rate (TPU), resulting in a similar net photosynthesis rate (An) to that of C plants. K+Ca treatment enhanced An, gs, Tr and Cc, particular under S condition, while it had no significant effects on gm, Jmax, Vcmax and TPU. Salt-induced increases in Jmax, Vcmax and TPU were associated with higher [N]leaf and [P]leaf, whereas the Jmax/Vcmax ratio decreased with increasing [N]leaf and [P]leaf, and Cc decreased with increasing [N]leaf. Salt-induced improvement in AC was linked to lower Jmax/Vcmax ratio and Cc, while the increase in AL could be ascribed to the lower non-photochemical quenching and higher photosystem II efficiency, which could be partially attributed to the salt-caused improvement in leaf superoxide dismutase, peroxidase and catalase activies. In conclusion, 150 mM NaCl salinity increased stomatal limitation but decreased non-stomatal limitation on An, resulting in sustained An and significantly lowered gs and Tr, and hence an improved water use efficiency. K and Ca addition could alleviate the salinity-induced decrease in gs and increase in stomatal limitation.
AB - To study the response of photosynthesis of cotton plants to salinity, and K and Ca fertigation, leaf gas exchange, light and CO2 response curves, chlorophyll fluorescence parameters, leaf N, P, Mg, K, Na and Ca concentrations, and antioxidant enzyme activities were measured. Cotton plants were grown at either 0 or 150 mM NaCl salinity (C and S treatment, respectively), and fertigated with or without K and Ca addition (O and K+Ca treatment, respectively). The results showed that 150 mM NaCl salinity decreased stomatal conductance (gs), transpiration rate (Tr) and chloroplast CO2 concentration (Cc). Yet it increased light saturated photosynthetic rate (AL), CO2 saturated photosynthetic rate (AC), mesophyll conductance (gm), maximum electron transport rate (Jmax), maximum Rubisco carboxylation rate (Vcmax) and triose phosphates use rate (TPU), resulting in a similar net photosynthesis rate (An) to that of C plants. K+Ca treatment enhanced An, gs, Tr and Cc, particular under S condition, while it had no significant effects on gm, Jmax, Vcmax and TPU. Salt-induced increases in Jmax, Vcmax and TPU were associated with higher [N]leaf and [P]leaf, whereas the Jmax/Vcmax ratio decreased with increasing [N]leaf and [P]leaf, and Cc decreased with increasing [N]leaf. Salt-induced improvement in AC was linked to lower Jmax/Vcmax ratio and Cc, while the increase in AL could be ascribed to the lower non-photochemical quenching and higher photosystem II efficiency, which could be partially attributed to the salt-caused improvement in leaf superoxide dismutase, peroxidase and catalase activies. In conclusion, 150 mM NaCl salinity increased stomatal limitation but decreased non-stomatal limitation on An, resulting in sustained An and significantly lowered gs and Tr, and hence an improved water use efficiency. K and Ca addition could alleviate the salinity-induced decrease in gs and increase in stomatal limitation.
KW - Antioxidant enzyme
KW - Fertigation
KW - Non-stomatal limitation
KW - PSII efficiency
KW - Photosynthesis
KW - Salinity
UR - https://www.scopus.com/pages/publications/85215398994
U2 - 10.1016/j.envexpbot.2025.106092
DO - 10.1016/j.envexpbot.2025.106092
M3 - 文章
AN - SCOPUS:85215398994
SN - 0098-8472
VL - 230
JO - Environmental and Experimental Botany
JF - Environmental and Experimental Botany
M1 - 106092
ER -